Professor Jerzy Bański
email: jbanski@twarda.pan.pl

Dilemmas for regional development in the concepts seeking to develop Poland's spatial structure

Keywords: Poland, spatial planning, physical development, spatial structure. Jerzy Bański 发发发发发发发发发发发发发发发发发发发发发发发发 发发发发发发发发发发发发发发发发发发发发发发发发发 über die Idee, der Effizienz eine höhere Priorität einzuräumen als der Gleichheit. In diesem Artikel analysieren wir diese drei Konzepte hinsichtlich ihrer Ansätze zur gleichmäßigeren Gestaltung der Regionalentwicklung das mit jedem der untersuchten Konzepte auf eigene Weise versucht wurde, die regionalen Disparitäten zu verringern; allerdings wurde keine der hierbei entwickelten Ideen jemals tatsächlich richtig umgesetzt Polen, Raumplanung, Physische Entwicklung, Raumstruktur Polonia, Planificación espacial, Desarrollo físico, Estructura espacial

Post-War Poland has seen work done on three spatial development concepts. The first -from the late 1940s -had as its task the decentralisation of industry and the strengthening of regions whose development had been lagging behind. The second -drawn up in the 1970spromoted the system of moderate polycentric concentration and a shifting of part of the country's industrial potential to more weakly-developed areas. In turn, the third conceptfrom the 1990s -again concentrated on balancing regional development, albeit through the idea of priority being assigned to efficiency over equality. The aim of the present article has been to analyse the aforesaid three concepts as regards the approach taken to the evening out of regional development. The primary thesis here is that the concepts studied strived in their various different ways to reduce regional disparities, but never actually had the ideas they came up with put into effect properly.

La posguerra de Polonia se ha caracterizado por un trabajo realizado en torno a tres conceptos de desarrollo espacial. El primero, que tuvo lugar desde finales de la década de los cuarenta, fue la tarea de descentralizar la industria y el fortalecimiento de las regiones cuyo desarrollo había quedado rezagado. El segundo, redactado en los setenta, fomentó el sistema de concentración policéntrica moderada y el traslado de una parte del potencial industrial del país a zonas menos desarrolladas. Y el tercer concepto, desarrollado a partir de los noventa, se centró de nuevo en equilibrar el desarrollo regional, aunque mediante la idea de dar prioridad a la eficacia en detrimento de la igualdad. El objetivo del presente artículo ha sido analizar estos tres conceptos mencionados con respecto al enfoque para igualar el desarrollo regional. La tesis principal aquí radica en que los conceptos estudiados intentaron, mediante sus Changes in Poland's political and economic system have combined with the country's accession to the EU to make the devising of new spatial development concepts a necessity.

The choice of an appropriate strategy by which to develop the country's spatial structure is crucial for future generations, and for determination of Poland's place in Europe. In this process of selection, the major dilemma is -as often -to establish whether it is the priority of equality, or that of efficiency, which represents the best solution. If "efficiency" were to win out, then the decision would be to focus on the promotion of strong regions, thereby further enhancing spatial polarisation. On the other hand, if "equality" is chosen, the weaker regions are to be helped, with a view to inter-regional disparities being limited, in full awareness of the fact that what the strong regions are able to achieve will in this way be limited (Fig. 1).

According to the founders of the contemporary vision of the country's development, who have accepted the doctrine of polycentric concentration and diffusion, the reality of Polish life necessitates (and the need to seize a chance of escaping from civilisational backwardness dictates) that efficiency should be prioritised ahead of equality (Koncepcja…1999). In the view of proponents, it is necessary to come to terms with the market economy's natural tendency to generate polarised spatial development. The most direct route to obtaining more effective economic development is then perceived to lie in a focusing of socioeconomic activity in places most suitable for the location of capital. These include nodes, belts and zones of activity, entrepreneurship and innovation. With the help of the state, the latter are considered capable of driving wider diffusion of the said innovation, ultimately exerting an activating impact at the level of the spatial structure of the country as a whole. In studying inequalities in spatial development, we continue to take account of the coreperiphery theories whose theoretical foundations were first put in place by F. Ratzel (1896), before gaining full development under J. [START_REF] Friedmann | Ogólna teoria rozwoju spolaryzowanego" (A general theory of polarised development)[END_REF]. Cores are territorially arranged subsystems in society, standing out in their marked capacity to generate innovation. The peripheries are those regions outside the cores, whose development will nevertheless depend on them. In the opinion of J. Friedmann, an appropriate shaping of the spatial structure may simultaneously offer a chance to ease the core-periphery duality. Supporters of dependence theory in turn claim that regions' poverty does not reflect their isolation and limited spatial integration, but rather the asymmetry characterising relations with the economic system. Thus the benefits of development for the core do not extend to the peripheral areas.

The theory of poles of growth -above all linked with the name of F. Perroux (1955) also implies the existence of development-related inequalities. Poles of growth may be set against the "critical zones" considered to lag behind (as in [START_REF] Bański | Obszary problemowe w rolnictwie Polski[END_REF]. In turn, the classification of regions from L. [START_REF] Klaassen | Area Economic and Social Redevelopment: Guidelines for Programmes[END_REF] contrasts those of prosperity with areas of poverty.

Such issues of regional inequality have long been discussed and debated, a focus for a certain dissatisfaction or even anger being the sheer durability of the phenomenon in question.

Proponents of the theory of equilibrium see existing differences in supply and demand for capital and labour as sufficient in themselves to bring about a reduction in developmental disparities between regions. Assuming that capital and labour are freely mobile between rich regions (A) and poor ones (B), investment will begin to flow from A to B, while workforce passes from B to A. In this way, inter-regional differences will in some way be evened out as time goes by. In turn, in the view of advocates of the theory of cumulative causality, regional disparities will only increase (as the benefits of a cheap labour force prove no match for the overall benefits agglomerations have to offer). There will thus be a compensatory shift adjusting for the high labour costs in region A, while the outflow of workers from region B will limit the high costs of "outflow" to region A. Developmental disparities may therefore intensify.

A third solution is assumed by the theory of polarised development. The first stage in the process of economic development is deemed to be an increase in regional disparities and a concentrating of capital in several core centres. However, as development continues, a point is reached at which centres of growth are saturated, and investors' interest in other parts of the country begins to grow. This ultimately leads to a convergence of regional development. It is this theory that current concepts for spatial organisation in Poland make reference to.

The present article aims to analyse concepts for the spatial development of Poland, first and foremost as these have addressed the problem posed by a highly-disparate spatial structure in which regions of (at least) adequate development exist side by side with areas living in poverty, and in general located peripherally. It is the concepts emerging since World War II that have been looked at in developing this article's primary thesis -which is that, notwithstanding a desire on the part of all the studied concepts to even out regional disparities, the practical activity actually pursued in line with them has left in place the marked imbalance whereby the country continues to be divided into rich and poor regions.

The analyzed concepts (also referred to as plans or policies) are the basic documents formulating the state's key principles underpinning a national spatial management policy for the next dozen or so years. These concepts focus on policy, i.e. a deliberate effort to shape the national space in keeping with priorities of the country's developmental strategy. Also, they determine the relations between the government's and local authorities' spatial policy. These It should be also stressed that these concepts had different status and role in the spatial policy of the country. A post-war concept was, for instance, a distinctly theoretical study not approved as an official governmental document and thus formed no basis for a national spatial management policy. Nevertheless, the study's premises were in many places congruent with the intentions of the then government. On the other hand, the concept being worked out in the 1990s was published and accepted as an official governmental document laying down the principles of the country's spatial management policy.

The vision of the period of Poland's reconstruction

In the century and a half over which Poland was subject to partitioning by neighbouring powers, the territories making up the country within its post-1945 borders were basically treated as peripheral. Under those circumstances, it is hard to envisage their having developed in any more planned way. Relatively speaking, it was the lands having been under the control of the Prussian Empire that progressed furthest in economic terms. The Austrian-controlled and Congress Kingdom (Russian-administered) parts were in a much worse position.

It is very much on account of what happened during the Partitions that the Poland of today continues to be afflicted by marked regional disparities in terms of the economy, the level of civilisational development and quality of life.

The years of Polish servitude and non-existence combined with the devastation of the First World War to ensure that the state finally re-established in 1918 was in urgent need of costly investment. Yet any more planned approach to this in the inter-War years was hindered, not only by the aforementioned economic and civilisational polarisation of Poland, Under these circumstances, what may be considered a rather impressive undertaking for the time was the construction of Poland's Central Industrial District, the goal being for important branches of industry to become located in the central part of the country (far from Germany), with economic activation stimulated in areas of "poverty". Seen in the context of the subsequent history, the Central Industrial District is one of the most courageous planning measures ever implemented in Poland, though a second important undertaking was the construction of the port in Gdynia, as well as of the coal line that linking it with Upper Silesia.

Ultimately, the Second World War made void the ambitious plans for Poland that might otherwise have been put into effect (war destroyed 65% of industrial plants, 35% of buildings, 55% of power stations and power lines, and 45% of machinery and facilities).

In the immediate aftermath of regained "independence" in 1945, Poland found itself beset with a number of urgent spatial planning tasks needing to be discharged. Thus 1946 brought the establishment of the Central Office of Spatial Planning (Główny Urząd Planowania Przestrzennego), whose primary task was to prepare a long-term spatial plan for the country known as the Study for a National Plan (Studium Planu Krajowego). The main focuses here were on:

the designation of land to meet the needs of different economic functions (agriculture, forestry, mining, etc.) and for the establishment of nature reserves, -the distribution of the population and the network of the main urban centres, -the distribution of networks of technical infrastructure, -the division of the country into regions as a basis for dividing the state administratively [START_REF] Toeplitz | 40 lat planninga struktury spatialej Polski" (40 years of planning Poland's spatial structure)[END_REF]. The first phase of the Study involved work on the three subject areas of communications, industry and the settlement network. Urbanisation and industrialisation were assumed to be "attracted" by traffic routes, above all concentrating at points where these intersect. In connection with this, abstract transit directions across Poland were delineated, these being linked up with points of entry on to Polish territory. The directions established in this way and taking the form of belts were later made more precise through searches for existing or proposed transport routes. It was at the intersections between the most important of these that the largest urban centres were found, while the crossings between the secondary routes were locations for urban centres of regional significance. Appropriate economic (agricultural, forestry-related or tourist) functions were ascribed to areas lying between the belts.

A second main theme of the work involved the locating of industry. When the distribution of the main centres of production was analysed, it became clear that these were excessively concentrated, with the effect that creative energy was draining out of weaklyindustrialised areas. For this reason, the Study's authors were keen to advocate a more even distribution of industry -something they considered achievable through a deconcentration of existing industrial districts and the founding of new centres with this kind of profile. Industry (especially heavy industry) was a basic factor behind economic development of the regions. Acknowledging the need to eliminate disparity in the level of development between different regions of Poland, the authors of the plan suggested creating new industrial centers. This was intended to stimulate economically the development of poorly industrialized areas, as well as attracting the population away from the overpopulated rural areas to urban centers.

The third subject of the distribution of the settlement network was also being worked on. Christaller's theory was invoked as a model for a hierarchical system of urban centres that was devised. The latter was adapted to the real distribution of towns and cities, the emerging settlement network being used to divide the country up into nodal regions (these in turn serving as a basis for a proposed administrative division).

The second stage of the Study focused mainly on agriculture and industry, these being transformed over three consecutive periods of reconstruction, industrialisation and urbanisation. Thus, in the case of agriculture, the first two phases involved allocation of the "excess" farming population to areas of land abandoned by the Germans, and subsequently to industrial areas. The urbanisation phase in turn anticipated the shaping of an ever-greater regional emphasis to agricultural output (Fig. 2). In the case of industry, the first phase entailed renewed start-up in production centres that remained in existence after the War, as well as the designation of non-industrialised areas. The second phase, in turn, involved the deconcentration of industry, and the third its ultimate dispersion.

In 1948, a wave of criticism of economic planning and of the concepts being implemented by the Central Office of Spatial Planning broke out. As A. [START_REF] Jezierski | Historia gospodarcza Polski[END_REF] The authors of the plan, who suggested developing the new industrial centers in the economically backward areas as well as a balanced settlement network, opted for prioritising equality ahead of efficiency. Despite the fact that the plan was not oficially put into effect, a lot of its solutions were actually implemented. This concerns primarily deconcentration of industry and 'the enriching' of the settlement network with new cities (for more information see chapter 2).

Fig. 2

Post-War planning was no longer deemed to reflect interplay on the market, but rather decisions taken at central level. These deployed the labour force, as well as determined what would be produced and for whom, and where industry and all fundamental elements of infrastructure would be located. Thus, unlike the market economies, communist countries could ostensibly activate poorly-developed regions simply by locating new industrial development there. However, the activation of regions was inflexibly equated with the location and development there of (heavy) industry, as opposed to any other possible means.

Indeed, even the technical and social infrastructure that might have raised the effectiveness of investment in plants was very much overlooked.

According to K. [START_REF] Dziewoński | Przekształcenia przestrzenno-gospodarczej struktury kraju" (The transformations of the spatio-economic country's structure)[END_REF], it was the wartime destruction that made a radical makeover of Poland's spatial structure possible, the aims pursued being the evening-out of inter-regional disparities and the decentralisation of industry. Alas, the extremely pressing day-to-day needs of the country at that point made it necessary for production to be started up -and assets restored -however and wherever that was at all possible. The regrettable side-effect of this was for the previously-existing spatial structure to be largely reinstated. Thus, just several years after the War's end, the spatial structure of Poland was characterised by major divides in terms of both social and economic development.

Basic elements in the state's spatial structure at that time were the network of communications linking the most important urban centres, as well as two main axes of industrial development (Fig. 3). Where the communication linkages were concerned, there was a very visible absence from the north of the country, as compared with a tendency towards concentration in the centre. The two axes of industrial development referred to passed through Upper Silesia, at that time the country's main pole of development. Thus, disparities centred first and foremost around a divide between the poor east and the better-invested-in west. There were also glaring disparities in the distribution of the main urban centres, these being concentrated in central and western parts of Poland.

Fig. 3

Later years enjoyed a rapid rate of industrial development and urban population (Figs. 4,5). The 1950-1955 Six-Year Plan assumed the development of heavy industry, but investment overstretch ensured a steady slowdown in the rate of investment, to the point where disquiet in society was even aroused. Nevertheless, new industrial centres did emerge in subsequent years, the result being a more even distribution of industry nationally, which is to say, a process of deconcentration. A result of these transformations was that the configuration of main elements to the country's spatial structure gained several new medium-sized urban centres, which assumed new functions as urbanisation progressed. Towns and cities came to be linked together by a denser communications network, though the heaviest concentration continued to characterise central Poland. While the intended, more even distribution of industrial plants was achieved to some extent, Silesia remained the clear dominant where this branch of the national economy was concerned. Nevertheless, a wider, more-highly-industrialised area did arise, this occupying a large triangular-shaped area on the map of Poland (Fig. 6). All the major urban agglomerations were to be found within this zone. (Leszczycki, Eberhardt and Heřman, 1971).

In the view of the authors, what were at that time being created within spatio-economic structures were integrated settlement complexes in the form of large cities in which development potential was accumulating, while strong interlinkages of a social and economic nature were making themselves felt along the main transport routes. Agglomerations were gradually absorbing the small towns and villages in their vicinity. Thus, the primary skeleton of the country's spatio-economic structure was to be provided by a polycentric system of nodes and belts, within which agglomerations were to serve as main nodes (Heřman and Eberhardt, 1973). Overall, the concept indicates directions to the development of urban settlement structure. However, some of its assumptions could not be complied with because of the economic crisis, difficulties with the system of central economic planning and the ongoing decline in the importance attached to large industrial plants. In the event, the sizes it anticipated for urban-industrial agglomerations and central agglomerations were too large.

There was also a lack of proposals for strengthening the urban settlement system in the north and east, i.e. those areas displaying marked disparities when set against the southern and central regions. As B. [START_REF] Malisz | Trzy wizje polskiej przestrzeni[END_REF] stressed, the concept for the development of urban agglomerations is characterised by a lack of faith in the effectiveness of spatial planning and, although this is most probably realistic, it is not very desirable from the social point of view.

Another concept concerning the transformation of the settlement network in the Plan was that devised by B. [START_REF] Malisz | 40 lat planowania struktury przestrzennej Polski" (40 years of planning Poland's spatial structure)[END_REF]. Its main assumption was that innovation (as the basic factor in economic development) progresses along certain belts or routes, since it is along these that the best conditions for the development of industry exist. It is in turn at the points where these intersect that we find the most favourable conditions for the establishment of centres for the services. The development of towns and cities increases the significance of the routes, and that in turn affords yet further opportunities for development. A second assumption in turn holds that human progress is guided by the principle of least effort (i.e. that attempts to achieve goals are made with the smallest possible inputs of energy and labour). This means that the spatial structures created are permanent, and comprise linear, ). Its ambitious visions were verified by the then central authority, for the plan had above all to take account of the assumption that Poland's economic development would be dynamic. Ultimately, the aims regarding development of the settlement network found themselves based around the "system of moderate polycentric concentration". Urban centres were to develop at varying speeds, i.e. with slow growth of the agglomerations already developed, compared with intensive growth of developing agglomerations, potential agglomerations and centres of national significance. This measure was thus a favourable one from the point of view of the balancing of regional development.

The Plan adopted a series of other provisions on socioeconomic life, the overall aim being to limit the role of industry as the only factor in the development of regions, while at the same time reinforcing the positions of agriculture and tourism. The main strategic objective was to shift part of the industrial potential from the south of the country to northern and eastern areas. Industry was to develop there, in smaller urban centres in particular. Where the agricultural economy was concerned, the assumption was of a relatively even spatial breakdown to the structure of the basic elements of agricultural output. There were very ambitious intentions when it came to the development of the road network, first and foremost the motorways. By 1990, there were to have been both north-south and east-west motorways, while the post-1990 period was to have focused on the construction of several new sections of motorway not even considered in planning today (Fig. 7).

It can be claimed that a priority of a balanced development of regions played a superior role in that plan. Indicative of that was especially the suggested system of a moderate polycentric concentration favouring a large group of medium-sized cities that were to develop dynamically. It was also congruent with the national administrative reform of 1975 that led to replacing the three-level division (voivodship-poviat-commune) with two-level one (voivodship-commune) and to establishing the new 49 ones in place of the then existing 14 voivodships (forming the regional centers of development on the basis of the urban agglomerations and medium-sized cities). This was a clear indication of simplification and deconcentration of the system of administration. A great many economists were not convinced of the necessity to bring into existence such a great number of voivodships, a large portion of which were entities poorly developed socially and economically. These underdeveloped voivodships were unable to compete with well-developed entities based in powerful industrial centers or in large urban aglomerations. Subsequent administrative reform carried out in 1999 (at the same time a new concept of a national spatial management policy was accepted), was, to a large extent, a return to the earlier division (16 voivodships and the three-level administrative division) promoting again first and foremost major urban agglomerations. Fig. 7 While the Plan did win the acceptance of the then political authorities, it was even so implemented to only a very limited degree. This reflected inherent internal weaknesses of the Plan itself, the "over-scaling" of its economic assumptions, criticism of the idea that agglomerations might develop excessively, the fact that large industrial developments were often sited in contravention of the Plan's assumptions, incompetent decisionmaking at the centre and many other external factors.

As has been noted already, very large outlays went on the development of Polish industry, much of the money in question being targeted at regions in need of economic activation. Inevitably, the results were less dramatic than had been anticipated, first and foremost because of the stubborn persistence with the heavy industry option, as set against rather limited expenditure on means of consumption. While the solution of the huge industrial plant was turned to again and again, most of the weakly-developed areas into which these were slotted lacked the necessary background conditions for such investments. Thus, once again, a concept for the country's spatial development prepared by a large team of scientists and practitioners emerged as an "on paper" study, not more readily "translatable" or applicable in practice. The scientific diagnosis of the state of management of the country's spatial structure, together with a proposal as regards the solving of some of the problems posed by excessive inter-regional disparities in development, never actually lived to see the proper solutions implemented. The country was faced with an ever-deeper economic crisis and an associated ongoing intensification of spatial polarisation. Relatively the best economic situation was that facing the large urban agglomerations and industrial districts. In contrast, there was an intensification of unfavourable population processes in the eastern regions in which agriculture still prevailed (notably out-migrations and an ageing of the population remaining in the countryside).

Introduced in 1975, a two-tier structure for field-based organs of authority and the state administration (voivodships and gminas) necessitated changes in the system of spatial planning. The national spatial management plan represented an integral part of a prospective plan of socio-economic development, as well as serving as a basis for the drawing up of lower-order plans (for macroregions, voivodships, towns and gminas).

Further work done in the 1980s aimed to determine the premises that would underpin a new national plan of spatial management. The political and economic situation at that stage proved unfavourable to the dreaming up of far-reaching plans, hence the focus in published research results and expert opinions on criticism of the earlier planning activity and on the search for new developmental pathways where spatial planning and regional studies were concerned (Problemy polskiej przestrzeni 1982, Przestrzenna organizacja...1981, Przekształcenia miast...1982, Strategia uprzemysłowienia...1982).

A contemporary concept of spatial organisation

The 1980s were thus a time of rather slow growth in industrial investment, ensuring rather little change in the structure of Poland's spatial organisation. In contrast, the years from 1989 onwards saw a now-free Poland faced with a quite new political, social and economic reality that required (and did indeed generate) a process of radical transformation that swept through all the elements making up the state as a socioeconomic entity. A collapse of industrial output was one of the less desirable results, reflecting a marked drop in society's purchasing power, reduced demand for investment and supply goods, an influx of Western products and a severing of some cooperative linkages [START_REF] Wieloński | Geografia przemysłu[END_REF]. Fortunately, the decline in industrial output was not prolonged (see Fig. 5). It began to bottom out as early as in 1992, though the nascent economic revival was mainly based around services and commerce, the role played by industry in the national economy having declined irrevocably.

Post 1989, the opening up of borders and great desire on the part of Poland to return to the fold of Western European civilisation underpinned ever-fuller incorporation within continent-wide spatial structures. While the country's geopolitical location had never failed to be a matter of significance, political intervention under the previous system had left Poland in a less-than-ideal position as regards the physical development concepts, and one which it would not necessarily have occupied had all other things been equal. Today, location is of course one of the most important elements conditioning the development of Polish space.

The process of (European) "Unionisation" (entailing adaptation, harmonisation and approximation of Polish space to the conditions and parameters in force in the EU) resulted in Polish space becoming European Community space [START_REF] Kukliński | Polska przestrzeń w europejskiej perspektywie XXI wieku[END_REF]). Indeed, there has been an important role to be played in this context, since the eastern part of Poland is at the same A number of opportunities are thus afforded by Poland's location on the continental scale and regionally (i.e. in Europe in general and its Central and Eastern part in particular), even though this may also represent a source of conflict. Both the former and the latter follow from a location sandwiched between Germany as a major economic player in the world, and Russia -as a global (super) power.

In the view of J. [START_REF] Kołodziejski | Polska przestrzeń w europejskiej perspektywie XXI wieku[END_REF], Poland has a beneficial geographical and economic location, allowing it to serve as an important focus in the integrating space of Central and Eastern Europe. Among other things, such a location facilitates the flow of innovations, goods and persons, creating favourable conditions for the locating of enterprises and for the inclusion of Poland's economy within European competitive space. It also opens up potential where tourism and environment-related activities in Poland's natural space are concerned.

Polish space is thus treated as a keystone of Europe's integration processes, in both the vertical and horizontal configurations. Ongoing in the east-west direction is a process of integration involving the EU on the one hand and the Euro-Asiatic Commonwealth of Independent States on the other, while in the north-south direction, Baltic Europe is proceeding to integrate with South-Eastern Europe [START_REF] Kołodziejski | Koncepcja polityki przestrzennego zagospodarowania kraju[END_REF]).

However, the impression continues to be that the north-south direction plays a less important role in Poland than the east-west. For this reason, that "keystone" location between Europe's Baltic Region and South-Eastern Europe (mainly Romania and Bulgaria) is better treated as an idea -and opportunity, than as a fact -or existing strength. The Baltic Sea in the north and mountainous areas in the south continue to present major barriers to all kinds of "movements" or "flows" in this direction. Moreover, the socioeconomic potential of the Equally, the concepts for Europe's spatial development emerging in the late 1980s and early 1990s did rather tend to place Poland on the periphery of any areas playing a more major role in continent-wide social and economic development. In effect, this was just another one of those post-Communist countries linked but weakly with EU space. This kind of attitude is equally discernible in the so-called "European banana" or "Blue Star" concepts, or indeed as regards the so-called "islands of innovation".

While things have moved on, Poland's incorporation into the EU system as regards spatial structure has done little to change that peripherality of location. The eastern part of the country is a true margin of the European Union, resembling other marginal areas on the continent in lacking opportunities for dynamic development. The thrust to such thinking is conceptualised synthetically in the sustainable development model (Fig. 8). To be distinguished within this are three main spatial elements, i.e. potential poles of polarisation, potential belts of accelerated development and potential zones of multifunctional development with a zone of accelerated development.

The poles of polarisation are to be: the capital city metropolis (competing with Vienna, Prague and Budapest, for example), the so-called Europolises (The Gdańsk-Gydnia-Sopot Tri-City, Poznań, Kraków, Wrocław -and potentially also Szczecin, Łódź, Katowice, Lublin, Białystok, Rzeszów and Toruń-Bydgoszcz) and the national, supraregional and regional centres of the balancing of development. Through the process of international competition, the potential poles of development will create ever stronger nodes of innovation anticipated to have a nationwide impact.

The potential belts of accelerated development lie along the international and national systems of technical infrastructure, above all including the system of motorways and main roads, as well as the rail lines. What is noteworthy here is the relatively even distribution of The National Spatial Arrangement Policy has represented a basis upon which lower tiers of administration have drawn up their own documents of a similar nature. Thus, the regional assemblies (sejmiki) in the voivodships enact their voivodship development strategies and physical development plans that should be in line with the Policy. In turn, the devising of

Studies on the conditioning and directions to physical development and of Local physical

development plans is a gmina-level matter.

In line with its very generalised character, the voivodship physical development plan is not actually a local legal act, and does not impinge upon the entitlements enjoyed by gminas.

In turn, the Local physical development plan enacted by the gmina does stand out among all the planning documents in constituting local law. Above all, it contains information as to the designations of given areas of land, and the principles and conditions underpinning the assignment of land to different use categories.

In view of the brief period of time that has elapsed since drawing up the Policy, it is difficult to point out its practical meaning to spatial planning. Its acceptance occurred at the same time with implementation of the national administrative reform aiming to reintroduce large voivodships (on the basis of 49 voivodships, 16 new ones were formed). It may be pointed out that a priority of efficiency played here a crucial role. Thus, competitve and economically powerful agglomerations (now capitals of voivodships) were strengthened at the The contemporary image of the spatial structure of Poland results from multiple processes as well as political, social and economic phenomena. The three concepts for spatial organisation, considered here, contributed also to the formation of this image. In view of the fact the the concepts arose in various periods of political and economic development of the country, their objectives and challenges differed. Likewise, they had differentiated practical significance in terms of shaping the structure of spatial organisation. It should be emphasised that in the respective periods of preparation of all the three concepts a number of original studies were elaborated, which constituted important contributions to the knowledge and conceptual wealth of the domain of Polish spatial economy.

From the first concept (Study for a National Plan, Studium Planu Krajowego) no official planning document resulted, and so we can state that this concept had the nature of a theoretical study (a vision of development), which did not turn into practice. The elaborates worked out did not produce a consistent document, whose goals would have then be implemented. Yet, the prerequisites formulated and the adopted methods of work exerted an influence on the later planning undertakings. The fundamental challenges to this first concept were:

-deconcentration of industry, -development of the main elements of the infrastructure networks, -designation of the directions of development of the regions, All of the objectives mentioned aimed at optimisation of the spatial structure of the country and alleviation of the regional development differentials. Given that the work on this concept was interrupted, it can hardly be assessed. A part of the proposals that it contained were, however, being implemented in the following years.

The concept named "Poland 2000" had a different character and the methodology of its preparation differed, as well. The output from the "intellectual storm" among the representatives of academia and practice was constituted by the elaboration of a dozen or so original concepts for the development of the spatial structure of the country, which made the theoretical basis for the official document Plan for the spatial management of the country up to 1990 (Plan przestrzennego zagospodarowania kraju do roku 1990). The ultimate referee and editor of the document was the then state administration, subordinated to the Party, and so this one turned out to be not a realistic, but a "wishful" elaborate. The most important objectives, formulated in the document were:

-the concept of the moderate polycentric concentration, -the differentiated rate of growth of urban centres, -deconcentration of industry, with emphasis on the development of small industrial plants, -development of modern transport network.

Economic crisis of the country and deployment of large investment projects "outside of plan" caused that the practical significance of the concept was limited. That is why the differences in the levels of regional development, instead of getting smaller, deepened yet.

The third of the concepts considered, the National Spatial Arrangement Policy (Koncepcja polityki przestrzennego zagospodarowania kraju) had a broader dimension, for it referred, as well, to the position of Poland in Europe and the resulting thereof opportunities and threats. One of the dilemmas addressed in the document was to reconcile, on the one hand, competitiveness and efficiency, with, on the other hand, balanced regional development. The authors of this concept, though, concentrate on the former. They consider as the fundamental contemporary challenges the following ones:

-taking advantage of the :interface" position of Poland; -development of infrastructure (mainly of roads), -development of agglomerations as the poles of polarization.

These challenges clearly indicate the choice of efficiency ahead of equity. In this connection one could hardly expect the process of balancing of the regional development to take a proper course.

When the contemporary spatial structure is analysed, several fundamental elements can be distinguished, representing a particular kind of primary fabric for all the discussed planning studies. Included here first and foremost are the settlement network and the system of main transport routes. Within the former, the most important role is played by the mature agglomerations (Warsaw, Poznań, Kraków, Łódź, Wrocław, Gdańsk and Katowice), as well as the growing agglomerations (Bydgoszcz-Toruń, Szczecin, Białystok and Lublin). In turn, the key features of the system of transport routes are the existing and planned motorways, as well as the railway main lines.

It is upon the foundation this basic fabric provides that the central and western parts of Poland are forming up into a contiguous area of elevated developmental potential (Fig. 9). Within this are northern, central and southern areas of accelerated development that may be deemed capable of drawing benefit (or less charitably "taking advantage" or even "exploiting") other regions. They are a "magnet" attracting investment, capital and people, their economic and social potential being sufficient to ensure competitive interaction in the global market place, alongside other areas of Europe. In the future, they will enlarge -most The areas of elevated development potential are surrounded by others that may be considered to be "benefited from" -or "taken advantage of/exploited", to use stronger language. In the main, these are within the economic peripheries of the country [START_REF] Bański | Obszary wiejskie w planowaniu przestrzennym[END_REF]. Their social potential is being sucked away -mainly by areas of accelerated development. The whole post-War period has thus been associated with an outflow of the young, best-educated and most entrepreneurial to more favoured areas.

In spite of several decades of struggle to reinforce the poorer regions economically, it has not proved possible to dislodge the spatial polarisation existing across Poland. This is confirmed by data on own income to the budgets of gminas (local authorities), this first and foremost comprising real-estate taxes, fares from means of transport and income tax from Białystok, and Lublin plus Rzeszów. These are suited to a role in stimulating progress and innovation because, as well as being administrative, service-related and commercial centres, these cities are also home to leading academic institutions.

An equally important role in any future balancing of development might be played by the belts of growth forming up along the Warsaw-Białystok-Suwałki, Warsaw-Lublin-Zamość, Białystok-Lublin-Rzeszów, Szczecin-Koszalin-Gdańsk and Szczecin-Legnica transport routes. The development of these belts will need to engage external resources, in particular to allow their technical infrastructure to develop and to ensure that investment in innovation is forthcoming [START_REF] Bański | Suburban and peripheral rural areas in Poland -the balance of development in the transformation period[END_REF]. In addition, a good feature of the belts may be their participation in international commerce, providing that steps are taken to limit a possible "tunnel effect", whereby the routes come to serve as nothing more than passive conduits for transit traffic. The 1970s boasted a wide range of different, more or less fully-developed concepts for the country's spatial development. The discussions over these were the stimulus underpinning the Plan for the Spatial Management of the Country to 1990 (Plan przestrzennego zagospodarowania kraju do 1990 r). The adopted system of moderate polycentric concentration and task of shifting part of the country's industrial potential from the south to weakly-developed regions in the north and east both attest to the attempt that was being made to even out the spatial structure. Unfortunately, the Plan proved over-optimistic in its assumption of very dynamic economic development in Poland, falling prey to the then ubiquitous propaganda of success. The later economic crisis again rendered implementation of most of the proposed tasks impossible.

The contemporary concept for the development of the country's spatial structure is in turn founded upon the theory of polarised development. This assumes the gradual spread of innovation and other developmental factors from areas of growth (dynamic development) into what is broadly understood as "the periphery" (i.e. areas of stagnation or slow development), the aim being for a convergence of regional development to be attained. However, in this regard, Poland would only seem to be taking its first steps on a long road, in which the consequences of areas being "sucked dry" are continuing to prevail over the more beneficial effects envisaged as the process of "propagation" continues.

The assumption behind all of these concepts is that developmental disproportions between regions need to be evened out. Various methods of attaining that goal have been devised. For example, the concept applying in the period of the country's post-War reconstruction assumed a transfer of large investments in industry into the marginal areas, this being thought likely to dynamise development. In turn, today's concepts advocate a balancing of development by means of competition and the polarisation of socioeconomic activity in selected nodes and developmental belts that gradually come to encompass ever larger areas. In the face of all this, the unfortunate truth is that the whole post-War period has seen intensifying spatial polarisation, leading in extreme cases to the emergence of areas of genuine poverty. While some of the tasks laid down in communist-era planning documents were even completed, the fruits of those labours were not strong enough to tackle spatial disparities existing across Poland. And -when all kinds of changes in the country's system of administration at last became possible, along with changes in the socioeconomic structure and Table. 1

  Fig.1

  treated as spatial planning documents, though they provide premises for drawing up projects comprising tasks carried out by the government within the framework of a national spatial management strategy.

  generally by the economic crisis affecting the whole world in the late 1920s and early 1930s.

  state, the then Central Committee of the Polish Workers' Party claimed that planning made use of bourgeois methods of calculating national income, bringing about a reduction within that of the role being played by state industry. However, the 1949 reform of spatial planning brought an end to work on the Study for the National Plan. The Central Planning Authority and Central Office of Spatial Planning were both closed down. Called into being in their place was the State Economic Planning Commission (Państwowa Komisja Planowania Gospodarczego), which implemented decisions taken by the Party's Central Committee.Over the next twenty years, planning objectives were more likely to be pursued in relation to divisions of the national economy than territorial ones. For this reason, objectives and tasks devised as part of the Study could never be put properly into effect. The Study may have been more theoretical than practical in character, pointing to the potential and high level of skill of planners, as well as shaping ways of proceeding for those who would implement future concepts.

Fig. 4

 4 Fig.4

  Fig. 5

Fig. 6 3

 6 Fig.6

  point and zonal elements. The point (or nodal) elements join the linear (belt-like) elements in forming the skeleton for the spatial structure. It is in the nodes and belts that intensive human economic activity is concentrated. Discussion of the above concepts stimulated work on the Plan for the spatial management of the country up to 1990 (Plan przestrzennego zagospodarowania kraju do

  frontier of the EU. This makes it a venue for cooperative cross-border ventures between Eastern Europe (i.e. the area beyond the borders) and the Union as a whole.

  north and south is at best marginal when set against those of Russia plus Belarus and Ukraine in the east, as well as Germany and other states beyond in the west.

  The systemic transformation made it imperative to work on new legal solutions as regards planning and physical development. 1994 saw the adoption of a new Spatial Planning Act that took account of solutions widely accepted and applied in Europe (e.g. the principle of ownership protection). There was also a decentralisation of tasks as regards spatial planning, including far-reaching transfer thereof to municipal level.Poland post-1989 found itself in a new socioeconomic reality that required diagnosis and a new look at its spatial structure. New research was thus taken up so that an up-to-date document setting out state policy on spatial development and physical planning over the upcoming 20 years might be drawn up. Work on the "National Spatial Arrangement Policy" (Koncepcja polityki przestrzennego zagospodarowania kraju) was completed in 1999.As the Policy makes clear, the key dilemma for physical development policy in Poland continues to lie with its capacity to reconcile contradictory postulates involving competitiveness and efficiency on the one hand, equality and justice on the other. Nowhere, be found clearly expressed opinion of the authors of the Policy about the choice of a national spatial managment policy. One may have an impression that a 'golden mean' is being sought. The authors of the Policy focus on efficiency, if maintaining steadfastly that this does not denote acceptance of further spatial polarisation. Equally, they are firm in their conviction that their choice (of efficiency) is the absolutely necessary one to make in the face of Polish realia, offering as it does the best chance of an escape from backwardness. The attempt made to reconcile opposing standpoints on competitiveness and equality depends on a fundamental principle that balanced development may engender efficiency. The concentration of socioeconomic activity in places of the greatest economic potential offering most to investors is to effect this balancing of development nationwide, over the longer time perspective.

  the country. Socioeconomic activity that is competitive on the European scale will be concentrated in the zone of accelerated development. The model for the balancing of development contained in the National Spatial Arrangement Policy is enriched by a further element in the form of the so-called Polish pole of development, taking in Warsaw, Kraków, Wrocław, Poznań and the Tri-City and emitting positive impulses into the surrounding areas.

  growth centers which, as a result of this reform, lost a part of their administrative and economic functions.

Fig. 8 5

 8 Fig.8

  the main directions of migrations.

  , and most especially as ones with an east-west orientation. The economic position of such growth areas is strengthened by planned motorways, as well as the redevelopment of national and international air links.

  natural and legal persons. Weakly-developed regions are characterised by a slower rate of increase in own income per inhabitant. The voivodships of eastern Poland (Lubelskie, Podkarpackie, Podlaskie and Świętokrzyskie) are among the poorest regions anywhere in the EU25, and are characterised by low own incomes to gmina budgets and relatively low rates of increase thereof.Tab. 1It is nevertheless thought of as important from the points of view of spatial planning and regional development strategies that support should be extended to areas of stagnation, whose development should be strengthened by way of deft policymaking. The main elements in the balancing of development in these areas should be the regional urban centres like Szczecin,

  Fig.9

a(

  completely new global geopolitical situation in which Poland was now free to operate -no new planning vision for the future of Poland appeared. It was almost as if concepts were afraid to put into words the need for change in the new circumstances. Poland faces new and important challenges centering on the race to catch up with Western Europe and be incorporated into the global economy. The new processes and phenomena associated with those objectives are steadily changing the internal face of the country. Among them are depopulation processes, the growth of metropolises, the search for new energy sources and so on. The influx of a large wave of foreigners is to be expected in the near future. These and other processes have combined to ensure that a start to work on a new concept for spatial organisation has now been made at last. The theoretical prerequistes and the first version of the document were elaborated at the Institute of Geography and Spatial Organisation of the Polish Academy of Sciences in 2008. After social consulting and verification at the Ministry of Regional Development this document shall become the basis for elaboration of the new Concept for the spatial development of the country 2008-2033. Bulletin of the Committee on Spatial Economy and Regional Palnning Polish Academy of Sciences), 125, pp. 6-45, Panstwowe Wydawnictwo Naukowe (PWN), Warszawa. Perroux, F., (1955) "Note sur la notion de "pôle de croissance", Economie Appliquée, 8, 1-2, pp. 307-320, Paris. "Plan przestrzennego zagospodarowania kraju do roku 1990" (A Plan for the Country's Spatial Management up to the Year 1990), (1974) Biuletyn KPZK PAN (Bulletin of the Committee on Spatial Economy and Regional Palnning Polish Academy of Sciences), 85, Panstwowe Wydawnictwo Naukowe (PWN), Warszawa. "Problemy polskiej przestrzeni" (Issues of Polish space), (1982) Biuletyn KPZK PAN (Bulletin of the Committee on Spatial Economy and Regional Palnning Polish Academy of Sciences), 118, Panstwowe Wydawnictwo Naukowe (PWN), Warszawa. "Prognozy rozwoju sieci osadniczej" (Forecasts for the development of the settlement network). Polska 2000, (1971) Komitet Badań i Prognoz "Polska 2000" PAN (the "Poland 2000" Research and Forecasting Committee of the Polish Academy of Sciences), Ossolineum, Warszawa. "Przestrzenna organizacja gospodarki polskiej. Próba analizy krytycznej" (The Spatial Organisation of the Polish Economy. Attempt of a Critical Analysis), (1981) Biuletyn KPZK PAN (Bulletin of the Committee on Spatial Economy and Regional Palnning Polish Academy of Sciences), 117, Panstwowe Wydawnictwo Naukowe (PWN), Warszawa. "Przekształcenia miast na tle przemian urbanizacyjnych" (The transformation of towns and cities against the background of urbanisation-related changes), (1982), Biuletyn KPZK PAN (Bulletin of the Committee on Spatial Economy and Regional Palnning Polish Academy of Sciences), 121, Panstwowe Wydawnictwo Naukowe (PWN), Warszawa.

  Figures

Fig. 2 .Fig. 3 .Fig. 4 .Fig. 5 .Fig. 6 Fig. 7 .Fig. 8 .Fig. 9

 23456789 Fig. 1. The major dilemma of the strategy for the spatial management of the country -

  . Own income to gmina (local authority) budgets in selected voivodships, expressed

	per inhabitant
	Voivodship	1995 (PLN)	2000 (PLN)	2006 (PLN)	Change 1995-2006 (1995=100%)
	Łodzkie	188	678	1151	614
	Mazowieckie	305	1176	2167	711
	Wielkopolskie	186	664	1167	626
	Pomorskie	230	782	1462	636
	Lubelskie	153	463	761	497
	Podkarpackie	143	448	761	531
	Podlaskie	150	471	885	589
	Swiętokrzyskie	152	481	791	519
	Source: Central Statistical Office

http://mc.manuscriptcentral.com/cres Email: regional.studies@newcastle.ac.ukRegional Studies

< O -Economic Development, Technological Change, and Growth, O18 -Regional, Urban, and Rural Analyses < O1 -Economic Development < O -Economic Development, Technological Change, and Growth, O21 -Planning Models|Planning Policy < O2 -Development Planning and Policy < O -Economic Development, Technological Change, and Growth, R1 -General Regional Economics < R -Urban, Rural, and Regional Economics


Jaroslav Koleček
email: j.kolecek@email.cz

Jiří Reif

Karel Šťastný

Vladimír Bejček

K Ńťastný

Changes in bird distribution in a Central-European country between 1985-1989 and 2001-2003

Keywords: bird community, species richness, distribution, central Europe, global change, land use

come   L'archive ouverte pluridisciplinaire

Introduction

Biodiversity conservation is one of the fundamental objectives of current initiatives for nature protection [START_REF] Primack | Essentials of Conservation Biology[END_REF]. Although most attention is paid to the ongoing decline of global species richness [START_REF] Swanson | The Economics and Ecology of Biodiversity Decline: The Forces Driving Global change[END_REF], we should bear in mind that management measures are most frequently implemented at local or regional levels, usually within individual states [START_REF] Lenzen | Effects of Land Use on Threatened Species[END_REF]Yamamura 2008;[START_REF] Orłowski | Changes in breeding bird populations in farmland of southwestern Poland between 1977-1979 and 2001[END_REF]. Local change in species richness is determined by the number of species which colonize the area and the number of species that disappear. Local colonization and extinction rates are related to the sensitivity of particular species to current changes in the landscape [START_REF] Donald | Inventory of major landscape changes in the Czech Republic, Hungary, Romania and Slovak Republic 1970s-1990s[END_REF][START_REF] Lenzen | Effects of Land Use on Threatened Species[END_REF]. For effective conservation management it is, therefore, important to see whether species undergoing range retraction have different ecological traits from species with expanding ranges. For this purpose, we can examine the mean change in regional distribution of groups of species with defined ecological characteristics [START_REF] Gregory | Developing indicators for European birds[END_REF], Jiguet et al. 2007[START_REF] Van Turnhout | Lifehistory and ecological correlates of population change in Dutch breeding birds[END_REF].

Such an "ecological-group" approach has been used successfully for the examination of temporal changes in regional breeding bird distribution in several Western European countries [START_REF] Gregory | The state of play of farmland birds: population trends and conservation status of lowland farmland birds in the United Kingdom[END_REF][START_REF] Julliard | Common birds facing global changes: what makes a species at risk?[END_REF][START_REF] Lemoine | Effects of Climate and Land-Use Change on Species Abundance in a Central European Bird Community[END_REF][START_REF] Van Turnhout | Scaledependent homogenization: Changes in breeding bird diversity in the Netherlands over a 25year period[END_REF][START_REF] Bauer | Avian species richness and abundance at Lake Constance: diverging long-term trends in Passerines and Nonpasserines[END_REF]). These studies have found prominent effects of various environmental changes on European birds such as the intensification of farming practices, urbanization and global climate change or habitat degradation on stop-over and wintering sites in the Mediterranean region and Sahel zone (Feranec et al. 2000;Jongman 2002, Opdam and[START_REF] Opdam | Climate change meets habitat fragmentation: linking landscape and biogeographical scale levels in research and conservation[END_REF][START_REF] Moreno-Rueda | Temperature differentially mediates species richness of birds of different biogeographic types[END_REF][START_REF] Schaefer | Impact of climate change on migratory birds: community reassembly versus adaptation[END_REF].

Despite this large body of evidence, our information about factors affecting changes in bird distribution is incomplete due to an apparent regional bias in these studies. Findings from former communist Central and Eastern European countries are based only on a few local scale results (e.g., [START_REF] Tryjanowski | Changes in breeding bird populations of some farmland birds in W Poland in relation to changes in crop structure, weather conditions and number of predators[END_REF][START_REF] Verhulst | Relationship between land-use intensity and species richness and abundance of birds in Hungary[END_REF][START_REF] Goławski | Changes in numbers of some bird species in the agricultural landscape of eastern Poland[END_REF][START_REF] Orłowski | Changes in breeding bird populations in farmland of southwestern Poland between 1977-1979 and 2001[END_REF] and their generalisation is thus problematic. At the same time, factors affecting bird distribution might differ between Western and Eastern European countries: agriculture was less intensive in the East [START_REF] Donald | Agricultural intensification and the collapse of Europe's farmland bird populations[END_REF], implementation of conservation legislation was delayed [START_REF] Donald | Inventory of major landscape changes in the Czech Republic, Hungary, Romania and Slovak Republic 1970s-1990s[END_REF]) and many migratory species use different flyways and wintering grounds [START_REF] Busse | European passerine migration systemwhat is known and what is lacking[END_REF][START_REF] Cepák | Czech and Slovak Bird Migration Atlas[END_REF]. The examination of whether the patterns found in Western parts of the European continent also hold true in former communist Central and Eastern European countries is thus of high conservation importance.

In this respect, birds of the Czech Republic represent an ideal opportunity to fill this knowledge gap. Their breeding distribution was mapped using a standardized technique in two mapping sessions during the last decades: in 1985-1989and 2001-2003. Moreover, their . Moreover, their ecological requirements are well known and documented [START_REF] Hudec | Fauna of Czechoslovakia: Birds III. Academia[END_REF][START_REF] Hudec | Fauna of the Czech and Slovak Republic: Birds I. Academia[END_REF][START_REF] Hudec | Fauna of the Czech Republic: Birds II. Academia[END_REF][START_REF] Cepák | Czech and Slovak Bird Migration Atlas[END_REF] enabling the sorting of particular species into various ecological groups.

Based on the results of studies of European bird communities, we can formulate the following predictions about recent changes in distribution of particular ecological groups of Czech birds. First, landscape changes, such as the loss of extensively cultivated farmland due to agricultural intensification or land abandonment followed by forest spread, should reduce the distribution of farmland birds and increase the distribution of forest species [START_REF] Lenzen | Effects of Land Use on Threatened Species[END_REF]Reif et al. 2008a;[START_REF] Orłowski | Changes in breeding bird populations in farmland of southwestern Poland between 1977-1979 and 2001[END_REF]. Second, the increase in the average annual temperature should have a positive effect on the distribution of south-European species and a negative impact on the north-European ones [START_REF] Bauer | Avian species richness and abundance at Lake Constance: diverging long-term trends in Passerines and Nonpasserines[END_REF]Reif et al. 2008b).

Third, global warming, along with the degradation of wintering habitats, should lead to an increase in the distribution of resident species and to a decrease of migrants [START_REF] Schaefer | Impact of climate change on migratory birds: community reassembly versus adaptation[END_REF]. Fourth, legal protection should have a positive impact on protected species compared to unprotected ones [START_REF] Donald | Inventory of major landscape changes in the Czech Republic, Hungary, Romania and Slovak Republic 1970s-1990s[END_REF].

The aim of the study was to examine these predictions comparing particular ecological groups of Czech birds between the two mapping periods. For each species group, we have focused on changes in breeding distribution. We have paid special attention to the species that colonized the country or went extinct between the mappings and how these species influenced the observed patterns.

Methods

Bird distribution data

We used data from the two atlases of breeding bird distribution (hereafter Atlases) in the Czech Republic covering the period 1985-1989 (Ńťastný et al. 1996) and 2001-2003 (Ńťastný et al. 2006). Data was collected in a unified network of 628 squares of 10´ longitude and 6´ latitude (roughly 12 by 11.1 km) evenly covering the entire territory of the country. The method of fieldwork was based on the contributions of a high number of volunteers (750 and 532 in the first and second mapping periods, respectively) and was the same in both Atlases.

Each volunteer was requested to survey all habitats in a selected square. It was recommended they start with the most frequent habitats (fields, meadows, forests, towns, villages, etc.) and then move onto rarer ones (water bodies, wetlands, streams, etc.). Finally, a targeted search was carried out for individual species in appropriate environments or at appropriate timese.g., at dusk in case of the owls, crakes, nightingales etc. Field observations of each bird species in the particular mapping squares were recorded using 17 numerical breeding codes with respect to the probability of its breeding occurence, according to the standards used in Europe [START_REF] Hagemeijer | The EBCC atlas of European breeding birds. Their distribution and abundance. T & AD Poyser, London Heldbjerg H, Fox TAD[END_REF].

The distribution of each species (hereafter occupancy) was expressed as the number of occupied squares with categories of "probable" or "confirmed breeding" (breeding codes 3-16 in [START_REF] Hagemeijer | The EBCC atlas of European breeding birds. Their distribution and abundance. T & AD Poyser, London Heldbjerg H, Fox TAD[END_REF] in respective mapping periods. There were 215 species conforming to these criteria.

Definition of explanatory variables

We have recognized the following species groups (Appendix 1) differing in (i) habitat requirements, i.e., forest species (78 species in the first and 80 in the second mapping), wetland species (61 / 65), farmland species (50 / 44) and urban species (19 / 19), (ii) migration strategy, i.e., resident species (45 / 44), partial migrants (22 / 23), short-distance migrants (71 / 74) and long-distance migrants (70 / 67), (iii) breeding distribution in Europe, i.e., northern species (68 / 69), southern species (53 / 51), central species (22 / 22) and widespread species (65 / 66), and (iv) legal protection in the Czech Republic, i.e., critically endangered (30 / 28), highly endangered (56 / 55), endangered (28 / 28) and species without any special legal protection (94 / 97). The terms like "endangered" do not describe the real level of threat but they are the title of the official categories of legal protection listed in Czech conservation law [START_REF] Anonymus | Environmental Yearbook of the Czech Republic 1995. Ministry of the Environment of the Czech Republic[END_REF]. Therefore, a "critically endangered" species is under the highest conservation concern according to Czech conservation law but in reality it may not be more threatened than other species. The real levels of threat to a particular bird species in the Czech Republic are currently unknown as no one has performed any formal analysis [START_REF] Voříńek | How effective can be the national law in[END_REF].

Most of the species used for further analyses were already sorted into these categories in [START_REF] Reif | Population trends of birds in the Czech Republic during 1982-2005[END_REF]Reif et al. ( , 2008b) ) and [START_REF] Voříńek | How effective can be the national law in[END_REF]. For the categorization of the remaining species, we used the following literature sources: [START_REF] Hudec | Fauna of Czechoslovakia: Birds III. Academia[END_REF][START_REF] Hudec | Fauna of the Czech and Slovak Republic: Birds I. Academia[END_REF] and [START_REF] Hudec | Fauna of the Czech Republic: Birds II. Academia[END_REF] for the habitat requirements, [START_REF] Anonymus | Environmental Yearbook of the Czech Republic 1995. Ministry of the Environment of the Czech Republic[END_REF] for legal protection status and [START_REF] Hagemeijer | The EBCC atlas of European breeding birds. Their distribution and abundance. T & AD Poyser, London Heldbjerg H, Fox TAD[END_REF] for the breeding distribution in Europe.

Determination of particular groups defined by different breeding distributions in Europe followed the two-step assessment procedure described in Reif et al. (2008b). First, we divided Europe into three large regions with respect to the location of the Czech Republic: the northern region had its southern boundary five geographical degrees north of the latitudinal midpoint of the Czech Republic, the southern region had its northern boundary five degrees south of the midpoint of the Czech Republic and the central region laid between the northern and southern regions. These regions broadly correspond to the biogeographical divisions of Europe. The Mediterranean region is in the south, the boreal region is in the north and the continental region is in the central part (European Environmental Agency 2006). In the second step, we measured the area of the breeding range of each species in each region and calculated the proportion of a region covered by the range of the focal species. Based on these proportions, we defined four species groups differing in the latitudinal distributions of their breeding ranges in Europe. As nearly all species occurring in the Czech Republic have relatively large European breeding ranges distributed in all three regions, we could not use strict criteria such as "northern species are those confined solely to northern region". Instead, we used a criteria focused on the avoidance of a region in which a species has the lowest proportion of its range. We thus recognized: (i) northern species whose ranges cover < 30% of the southern region (e.g., Turdus pilaris); (ii) southern species whose ranges cover < 30% of the northern region (e.g., Luscinia megarhynchos); (iii) central species whose ranges cover < 30% of southern and northern regions (e.g., Parus palustris); (iv) widespread species whose ranges cover more than 30% of the area of each region (e.g., Passer domesticus). Although such species sorting is arbitrary to some extent, and indeed 30% has no biological meaning, we trust that it mirrors the real latitudinal preferences of a particular species.

Migratory strategy of each particular species were excerpted from the new Czech and Slovak bird migration atlas [START_REF] Cepák | Czech and Slovak Bird Migration Atlas[END_REF] which is based on all known ringing recoveries of Czech birds up to 2002.

Statistical analysis

We calculated the change in occupancy (C) of each particular species between the two mapping periods using the formula introduced by [START_REF] Lemoine | Effects of Climate and Land-Use Change on Species Abundance in a Central European Bird Community[END_REF]:

C = (N 2 -N 1 )/((N 2 +N 1 )/2)
N 1,2 is the occupancy of a given species in the first and second mapping period, respectively.

Positive values of C indicate increasing occupancy, negative values decreasing occupancy and

where C = 0 there is an indication of no change [START_REF] Lemoine | Effects of Climate and Land-Use Change on Species Abundance in a Central European Bird Community[END_REF]).

To test whether mean occupancy of particular species groups increased or declined, we performed the one-sample t-tests. Each test tested the null hypothesis that the mean change in occupancy of a given group is zero. Performance of 16 repeated tests using the same dataset would result in an elevated risk of a Type I error (Zar 1996). To account for this factor, we have applied the Bonferroni correction, adjusting the 0.05 level of significance (α) to 0.0031.

To test whether mean changes in occupancy differ among the focal species groups, we have applied analysis of variance (ANOVA). First, we have performed one-way ANOVAs for each factor (i.e., habitat, European distribution, migratory strategy and protection status) separately. Tukey's HSD post hoc test was used to compare means where significant differences were found with the ANOVA. Second, we have examined the effects of each factor, controlling the influence of the others, using main-effects ANOVA.

Finally, we were interested in the influence of colonization/extinction processes on changes in the distribution of birds in the Czech Republic. For this purpose, we have excluded all species (n = 14) present only in one of the mapping periods and then repeated all the tests described above. Comparison of the outcome of the tests with and without such species revealed their possible influence.

Results

The number of species in the Czech Republic remained the same in both periods -208 species. Seven species went extinct in the Czech Republic during the time between the mappings (Falco vespertinus, Otis tarda, Burhinus oedicnemus, Charadrius hiaticula, Coracias garrulus, Lanius minor and L. senator) and, at the same time, seven species colonized the country (Egretta alba, Anas penelope, Tadorna tadorna, Pandion haliaetus, Aquila heliaca, Chlidonias hybridus and Otus scops). The prevailing characteristics of the species which were not registered in the second mapping period were: farmland habitat (six species), long-distance migratory strategy (six species), southern distribution (five species) and critically endangered protection status (four species). The colonizers were characterized by wetland habitat (five species), long-distance (three species) or short-distance migratory strategy (three species), southern distribution (three species) and no legal protection (four species).

The overall mean change in occupancy between both mappings was not significantly different from zero (Table 1a). Regarding particular species groups, we found a positive change in occupancy in forest and wetland species, short-distance migrants and non-protected species. After application of the Bonferroni correction, the result remained significant in the wetland species only (Table 1a). No group showed a significantly negative change in mean occupancy, although the result in farmland birds approached the 0.05 significance level (Table 1a).

We applied analysis of variance to test whether some ecological characteristics would predict differences among the species groups in their mean changes in occupancy. We have found that habitat requirements were the only significant predictor of these changes, as shown by both one-way and main effects ANOVAs (Table 2a, b, Fig. 1). Post hoc comparisons using Tukey's HSD tests showed that both forest (P = 0.0138) and wetland (P = 0.0001) species extended their distribution more than farmland species.

After exclusion of the 14 species present only in one of the two mappings, we found that the overall mean change in occupancy between the mappings was positive (Table 1b).

Further, the results showed increasing occupancy in southern species (Table 1b). Excluding colonizers and extinct species did not qualitatively change the results for forest, wetland and non-protected species (Table 1b). In contrast, change in short-distance migrants was no longer significant (Table 1b). After the Bonferroni correction, the overall average change in occupancy and change in southern and non-protected species remained significant (Table 1b).

Exclusion of the 14 species, present only in one of both mappings, did not reveal any significant results in both one-way and main effects ANOVAs (Table 2c,d).

Discussion

Our results based on the analysis of the large-scale mapping data showed four striking patterns of changes in breeding bird distribution in the Czech Republic between 1985-1989 and 2001-2003: (i) dominant effect of habitat over all other factors, (ii) weaker but significant effects of European distribution, migratory strategy and protection status in some tests, (iii) influence of rare species on most of the observed patterns, (iv) prevalence of positive changes in bird distribution over the negative ones. The effects of habitat and European distribution were in congruence with our initial predictions, but the legal protection status showed the opposite pattern to what we had expected. The effect of migratory strategy did not support our prediction of decline in long-distance migrants and increase of residents.

The effect of habitat was caused by expansion of forest and wetland species in contrast to farmland birds. Since this contrast was not significant after excluding species detected in one mapping only, the marked difference between these habitat-defined species groups is probably caused by the extinction of six farmland species between the mapping periods:

Falco vespertinus, Otis tarda, Burhinus oedicnemus, Coracias garrulus, Lanius minor and L.

senator. Their disappearance from the Czech Republic indicates a possible adverse impact of the recent land use practices on these species. This result is somewhat surprising as the decrease in agricultural intensity after the fall of communism probably reduced the rate of population decline of common farmland birds in the Czech Republic (Reif et al. 2008a), Poland [START_REF] Goławski | Changes in numbers of some bird species in the agricultural landscape of eastern Poland[END_REF] and Hungary [START_REF] Verhulst | Relationship between land-use intensity and species richness and abundance of birds in Hungary[END_REF]). This land use change obviously did not prevent more sensitive farmland species from extinction. The exact causes of the loss of these species remains unexplored. We can only speculate about the switch from an extensively cultivated agricultural landscape providing a heterogenous mosaic of habitats to either highly intensive agriculture or the complete abandonment of arable land in the key areas for populations of these species [START_REF] Konvička | Butterfly extinctions in European states: Do socioeconomic conditions matter more than physical geography?[END_REF][START_REF] Anonymus | Environmental Yearbook of the Czech Republic 1995. Ministry of the Environment of the Czech Republic[END_REF][START_REF] Ludwig | Large-scale land use change may explain bird species declines in semi-natural areas: the case of Black Grouse population collapse in Lower Saxony, Germany[END_REF]; see also Ńťastný et al. 1996). The disappearance of these highly specialized species is consistent with [START_REF] Kerbiriou | More species, fewer specialists: 100 years of changes in community composition in an island biogeographical study[END_REF] findings on the spread of tolerant species with a broad ecological niche leading to biotic homogenization of bird communities in France [START_REF] Devictor | Functional biotic homogenization of bird communities in disturbed landscapes[END_REF]) and the Netherlands [START_REF] Van Turnhout | Scaledependent homogenization: Changes in breeding bird diversity in the Netherlands over a 25year period[END_REF]).

The increasing occupancy of forest and wetland birds was found even if the species detected in only one mapping were excluded (although with lower significance). Therefore, we suggest that these patterns were caused mainly by extending distribution of common species already breeding in the Czech Republic and the colonization of the country by new species has only strenghtened this effect. In the case of forest birds, this result is in accordance with studies based on annual monitoring of populations of common species in the Czech Republic [START_REF] Reif | Population increase of forest birds in the Czech Republic between 1982 and 2003[END_REF]) and other parts of Europe [START_REF] Gregory | Population trends of widespread woodland birds in Europe[END_REF][START_REF] Van Turnhout | Scaledependent homogenization: Changes in breeding bird diversity in the Netherlands over a 25year period[END_REF]). It might be attributed to forest expansion, the alteration of forest age class composition towards older classes and/or by the impact of forest recovery after the reduction of imissions in the 1990s [START_REF] Reif | Population increase of forest birds in the Czech Republic between 1982 and 2003[END_REF](Reif et al. , 2008c)). The increase of wetland birds was also confirmed in local bird communities in central and western Europe [START_REF] Lemoine | Effects of Climate and Land-Use Change on Species Abundance in a Central European Bird Community[END_REF][START_REF] Van Turnhout | Lifehistory and ecological correlates of population change in Dutch breeding birds[END_REF][START_REF] Orłowski | Changes in breeding bird populations in farmland of southwestern Poland between 1977-1979 and 2001[END_REF] and was probably caused by lower hunting pressure and the fact that many newly established nature reserves in the country protected wetland habitats [START_REF] Málková | Important Bird Areas in the Czech Republic[END_REF].

Southern species that bred in the Czech Republic in both mapping periods extended their occupancy, corresponding with findings of an earlier study focused on annual changes in abundance of common birds in the Czech Republic (Reif et al. 2008b). This result is consistent with the observations of climate change impact on bird species [START_REF] Julliard | Common birds facing global changes: what makes a species at risk?[END_REF], Jiguet et al. 2007[START_REF] Bauer | Avian species richness and abundance at Lake Constance: diverging long-term trends in Passerines and Nonpasserines[END_REF]. It also corroborates predictions of future breeding bird distribution patterns modelled under various scenarios of climatic warming [START_REF] Huntley | A Climatic Atlas of European Breeding Birds[END_REF]. Increasing occupancy of southern species, however, vanished after the inclusion of the species which became extinct between the mappings. A more detailed focus on particular species uncovered the fact that decrease was caused by the extinction of the farmland species which were probably more affected by unfavourable land use practices than by the climate. This result implies that global warming itself is not a sufficient impetus for range expansion of the southern species, if their habitat is destroyed.

Regarding changes of distribution of birds with different migratory strategies, we have found two unexpected results: increased occupancy in short-distance migrants and no change in occupancy in long-distance migrants. The first pattern was driven by the expansion of several colonizers of wetland birds (Egretta alba, Anas penelope and Tadorna tadorna) and it was probably caused by habitat effects. The second pattern contrasts with observations of population decline of long-distance migrants in several western European countries (e.g., Lemoine et al. 2007, Heldbjerg andFox 2008) and might be attributable to the use of different migratory routes and/or wintering sites by the Czech populations [START_REF] Busse | European passerine migration systemwhat is known and what is lacking[END_REF][START_REF] Cepák | Czech and Slovak Bird Migration Atlas[END_REF].

Increasing occupancy was found in non-protected species and the same result was found in all species grouped together after the exclusion of species detected in one mapping only. These results imply that common birds probably benefited from changes in the Czech landscape after 1990. In fact, components of the environment, including water, air, forests and farmland were heavily affected by human activity within all of Europe in the late 1980s [START_REF] Moldan | Environment of the Czech Republic. Development and statement until the end of 1989[END_REF]). During the 1990s, the water quality and air pollution greatly improved and there was also a sharp decrease in agricultural intensity. These positive changes were also documented in Poland [START_REF] Goławski | Changes in numbers of some bird species in the agricultural landscape of eastern Poland[END_REF] and Hungary [START_REF] Verhulst | Relationship between land-use intensity and species richness and abundance of birds in Hungary[END_REF]). Moreover, forests, defoliated in extensive areas due to air pollution, started to recover [START_REF] Anonymus | Environmental Yearbook of the Czech Republic 1995. Ministry of the Environment of the Czech Republic[END_REF][START_REF] Reif | Population increase of forest birds in the Czech Republic between 1982 and 2003[END_REF]Reif et al. , 2008a)). At the same time, we have failed to find any significant positive effect of legal protection on the occupancy of species. The reason may lie in the low effectiveness of direct conservation actions [START_REF] Kumstátová | Assessment of conservation projects on animals endangered in the Czech Republic[END_REF]. Czech nature conservation is probably not able to take care of problematic bird species [START_REF] Voříńek | How effective can be the national law in[END_REF]. Further studies are needed to ensure that existing protected areas create suitable conditions for endangered birds' existence (e.g., [START_REF] Kollar | Zur Bestandssituation der Großtrappe (Otis t. tarda L., 1758) in Österreich[END_REF].

To our knowledge, our study is the first attempt to examine the patterns of changes in breeding bird distribution on a country-wide level within the former Eastern block. Compared to the previous studies based on population trends from annual monitoring schemes (e.g., [START_REF] Gregory | Population trends of widespread woodland birds in Europe[END_REF], Reif et al. 2008a, b, c), our breeding distribution mapping data involve information about uncommon species [START_REF] Van Turnhout | Scaledependent homogenization: Changes in breeding bird diversity in the Netherlands over a 25year period[END_REF]. They are, therefore, less biased and the observed patterns are more general. Our results imply that the major drivers of Zar JH (1996) Biostatistical analysis. Prentice Hall, New Jersey Table 1 Changes in species richness (total number of species in the country) and occupancy (number of occupied mapping squares) of birds in the Czech Republic between 1985-1989 and 2001-2003 as revealed by the country-wide breeding distribution altas mapping. Species were sorted into groups defined by their habitat requirements, migratory strategy, European distribution and legal protection status in the Czech Republic. Statistics refer to single sample t-tests that tested the significance of change in occupancy of each group between the mapping periods. Significant differences (P < 0.05) are in bold type and those significant after the Bonferroni correction (P < 0.0031) are underlined. Tests were performed with (a) and without (b) 14 species that colonized the country or went extinct between the mapping periods. See Methods section for a detailed description of the calculation of change in occupancy and for more details on the sorting of species into the ecological groups a) b)

P W N Athene noctua U R S H Aythya ferina W S N N Aythya fuligula W S N N Aythya nyroca W S C C Bonasa bonasia F R N H Botaurus stellaris W S C C Bubo bubo F R W E Bucephala clangula W S N H Burhinus oedicnemus A L S C Buteo buteo F P W N Caprimulgus europaeus F L W H Carduelis cannabina U S W N Carduelis carduelis U P S N Carduelis flammea F R N N Carduelis chloris U P W N Carduelis spinus F S N N Carpodacus erythrinus A L N E Certhia brachydactyla F R S N Certhia familiaris F R N N Ciconia ciconia U L S E Ciconia nigra F L S H Cinclus cinclus W R W N Circus aeruginosus W L C E Circus cyaneus F S N H Circus pygargus A L S H Coccothraustes coccothraustes F S S N Columba livia f. domestica U R W N Columba oenas F S W H Columba palumbus F S W N Coracias garrulus A L S C Corvus corax F R W E Corvus cornix A R W N Corvus corone A R S N Corvus frugilegus U P C N Corvus monedula U P W H Coturnix coturnix A L S H Crex crex A L N H Cuculus canorus A L W N Cygnus olor W P C N Delichon urbica U L W N Dendrocopos leucotos F R W H Dendrocopos major F R W N Dendrocopos medius F R C E Dendrocopos minor F R N N Dendrocopos syriacus F R S H Dryocopus martius F R N N Egretta alba W S S H Egretta garzetta W L S H Emberiza citrinella A R W N Emberiza hortulana A L W C Emberiza schoeniclus W S N N Erithacus rubecula F S W N Falco cherrug F P C C Falco peregrinus A P W C Falco subbuteo F L W H Falco tinnunculus U P W N Falco vespertinus A L C C Ficedula albicollis F L C N Ficedula hypoleuca F L N N Ficedula parva F L N H Fringilla coelebs F S W N Fulica atra W S W N Galerida cristata A R S E Gallinago gallinago W S N H Gallinula chloropus W S W N Garrulus glandarius F P W N Glaucidium passerinum F R N H Grus grus W S N C Haliaeetus albicilla W R N C Himantopus himantopus W L S N Hippolais icterina F L N N Hirundo rustica U L W E Charadrius dubius W L W N Charadrius hiaticula W L N N Charadrius morinellus A S N C Chlidonias hybridus W L S N Chlidonias niger W L C C Ixobrychus minutus W L S C Jynx torquilla A L W H Lanius collurio A L N E

  changes (agricultural intensification, forest expansion, global climate change, biotic homogenization) are probably similar across European regions, although local specificities of several aspects emerged (e.g., poor performance of legal protection). Future studies should focus in more detail on the investigation of particular drivers. in den letzten Jahrzehnten signifikant von dramatischen Umweltveränderungen betroffen worden. Die Effekte dieser Veränderungen auf den Artenreichtum und die Verbreitung in bestimmten Ländern sind nach wie vor schlecht verstanden, da hochwertige, großräumige Daten fehlen, die über die Zeit standardisiert sind. Dies trifft besonders auf Mittel-und Osteuropa zu. Anhand einer Modellgruppe von Vögeln in Tschechien (landesweite Atlaskartierungsdaten) haben wir untersucht, ob sich Langzeitveränderungen in Artenreichtum und Verbreitung zwischen 1985-1989 und 2001-2003 zwischen Artengruppen unterschieden, die anhand ihrer Habitatansprüche, ihrem Verbreitungstyp in Europa, ihrer Zugstrategie und ihrem nationalen Schutzstatus voneinander abgegrenzt sind. Außerdem haben wir die Effekte von Erstbesiedlungen und lokalen Ausrottungen auf diese Veränderungen untersucht. Während die Artenzahl im gesamten Land in beiden Zeiträumen gleich blieb (208 Arten), hat sich die Artenzusammensetzung verändert. Zunehmende Besiedlung (d.h. Zahl besetzter Kartenquadrate) wurde für in Wald-und Feuchtlandhabitaten vorkommende Arten, Kurzstreckenzieher und nicht geschützte Arten beobachtet. Im Süden vorkommende Arten veränderten ihre Besiedlung ebenfalls zum Positiven, doch dieses Muster verschwand nach der Einbeziehung von sechs Arten, die auf extensiv bewirtschaftetes Ackerland angewiesen sind und zwischen den Kartierungen ausstarben. Die gesamte Besiedlung aller Arten zusammengenommen zeigte positive Veränderungen, nachdem Erstbesiedler und ausgestorbene Arten ausgeschlossen worden waren. Wir schlagen vor, dass die Verbesserung der Umweltbedingungen nach 1990 die Verbreitung von häufigen Vögeln in Tschechien stabilisierte oder ansteigen ließ, und der Verlust mehrerer Arten könnte durch das Verschwinden spezifischer Ackerbautechniken verursacht worden sein. the Czech Republic (MSM 6198959212). The authors declare that they have no conflict of interest. protecting birds? A case study from the Czech Republic. Folia Zool 57:221-230 Yamamura Y, Amano T, Koizumi T, Mitsuda Y, Taki H, Okabe K (2008) Does land-use change affect biodiversity dynamics at a macroecological scale? A case study of birds over the past 20 years in Japan. Anim Conserv 12:110-119

Fig. 1

 1 Fig. 1 Mean changes in the occupancy of Czech birds between 1985-1989 and 2001-2003 according to their habitat requirements. The vertical bars denote 0.95 confidence intervals. In one-way ANOVA, F 3,211 = 6.6040 and P = 0.0003. Pairwise comparisons of means by the Tukey test gave the following results: Forest different from Farmland (P = 0.0138) and Wetland different from Farmland (P = 0.0001)

Table 2

 2 The effects of ecological characteristics of bird species expressed as four factors on changes in their mean occupancy between1985-1989 and 2001-2003 tested by one-way ANOVAs (seperate tests for each factor) with (a) and without (c) 14 species present in only one of the mappings, and by main effects ANOVAs (all factors included into one model) with (b) and without (d) 14 species present in only one of the mappings.

		Species richness	Change in	N	t	P	Change in	N	t	P
				occupancy				occupancy
		1985-9 2001-3	(± SE)				(± SE)
	Habitat requirements
	Farmland	50	44	-0.21 (± 0.11)	50	-1.92 0.0614	0.04 (± 0.06)	44	0.58	0.5626
	Forest	78	80	0.14 (± 0.05)	80	2.74	0.0076	0.09 (± 0.04)	78	2.33	0.0220
	Urban	19	19	-0.09 (± 0.06)	19	-1.42 0.1742	-0.09 (± 0.06)	19	-1.41 0.1742
	Wetland	61	65	0.28 (± 0.96)	66	3.10	0.0029	0.19 (± 0.07)	60	2.63	0.0107
	Migratory strategy
	Resident	45	44	0.02 (± 0.08)	45	0.24	0.8127	0.06 (± 0.06)	44	1.03	0.3096
	Partial migrants	22	23	0.14 (± 0.10)	23	1.34	0.1934	0.05 (± 0.06)	22	0.87	0.3934
	Short-distance migrants 71	74	0.19 (± 0.07)	74	2.64	0.0102	0.11 (± 0.06)	71	1.90	0.0619
	Long-distance migrants 70	67	0.01 (± 0.10)	73	0.08	0.9328	0.10 (± 0.05)	64	1.94	0.0571
	European distribution
	Central	22	22	0.02 (± 0.17)	23	0.09	0.9271	0.02 (± 0.13)	21	0.13	0.8947
	Northern	68	69	0.13 (± 0.08)	70	1.70	0.0930	0.11 (± 0.06)	67	1.70	0.0882
	Southern	53	51	0.10 (± 0.12)	56	0.86	0.3951	0.20 (± 0.06)	48	3.14	0.0029
	Widespread	65	66	0.05 (± 0.04)	66	1.23	0.2239	0.02 (± 0.03)	65	0.73	0.4708
	Protection status
	Non-protected	94	97	0.12 (± 0.05)	98	2.43	0.0168	0.06 (± 0.02)	93	3.29	0.0014
	Endangered	28	28	0.03 (± 0.06)	28	0.43	0.6692	0.03 (± 0.06)	28	0.43	0.6692
	Highly endangered	56	55	0.10 (± 0.09)	57	1.02	0.3137	0.14 (± 0.07)	54	1.86	0.0679
	Critically endangered	30	28	0.03 (± 0.20)	32	0.16	0.8769	0.19 (± 0.16)	26	1.21	0.2344
	Total	208	208	0.09 (± 0.05)	215	1.91	0.0576	0.09 (± 0.03)	201	3.00	0.0030

Acknowledgements Special thanks belongs to all the volunteers who participated in the collection of data needed to write this paper. We thank Karel Weidinger, Martin Paclík and two anonymous referees for their critical comments on the manuscript. Pamela and Kenneth C. Lewis improved the English. The study was supported by the Grant Agency of the Academy of Sciences of the Czech Republic (KJB601110919) and Ministry of Education of