Landscape change

Landscapes change because they are the expression of the dynamic interaction between natural and cultural forces in the environment. Cultural landscapes are the result of consecutive reorganization of the land in order to adapt its use and spatial structure better to the changing societal demands. Particularly in Europe, history has recorded many successive and even devastating landscape changes, which have left barely any relics today. Today, the changes are seen as a menace, as a negative evolution because they cause a loss of diversity, coherence and identity, which were characteristic for the traditional cultural landscapes that are rapidly vanishing. This growing concern is also expressed in the European Landscape Convention, which will be used as a start for the analysis in this article. Three periods of landscape dynamics are considered: the traditional landscapes before the important changes that started in the 18th century, the landscapes of the revolutions age of the 19th to 20th century, and the post-modern new landscapes. The combined effect of the driving forces such as accessibility, urbanization, globalization and the impact of calamities have been different in each of the periods and affected the nature and pace of the changes as well as the perception people have had about the landscape. Values change accordingly and so does the way of using and shaping the landscape. It is argued that this changing perception also influences what kind and aspects of landscapes are studied, protected and managed. Diversity and identity of cultural landscapes are central in the discussion. It is shown that coherence between small composing elements in a broader spatial context is important for the legibility of the landscape and that the ability to tell the (his)story of a place strongly enhances the identity and the overall value. This offers criteria for inventorying and assessing landscapes, which is needed to define future management and development. Although the general trends of future development of the European landscapes are rather well known, planning and managing future landscape remains difficult and extremely uncertain. The processes and management in past traditional landscapes and the manifold relations people have towards the perceivable environment and the symbolic meaning it generates, offer valuable knowledge for more sustainable planning and management for future landscapes.

This collaborative essay grows out of a debate about the relationship between aesthetics and ecology and the possibility of an ''ecological aesthetic'' that affects landscape planning, design, and management. We describe our common understandings and unresolved questions about this relationship, including the importance of aesthetics in understanding and affecting landscape change and the ways in which aesthetics and ecology may have either complementary or contradictory implications for a landscape. To help understand these issues, we first outline a conceptual model of the aestheticsecology relationship. We posit that:

The potential consequences of biodiversity loss for ecosystem functioning and services at local scales have received considerable attention during the last decade, but little is known about how biodiversity affects ecosystem processes and stability at larger spatial scales. We propose that biodiversity provides spatial insurance for ecosystem functioning by virtue of spatial exchanges among local systems in heterogeneous landscapes. We explore this hypothesis by using a simple theoretical metacommunity model with explicit local consumer-resource dynamics and dispersal among systems. Our model shows that variation in dispersal rate affects the temporal mean and variability of ecosystem productivity strongly and nonmonotonically through two mechanisms: spatial averaging by the intermediate-type species that tends to dominate the landscape at high dispersal rates, and functional compensations between species that are made possible by the maintenance of species diversity. The spatial insurance effects of species diversity are highest at the intermediate dispersal rates that maximize local diversity. These results have profound implications for conservation and management. Knowledge of spatial processes across ecosystems is critical to predict the effects of landscape changes on both biodiversity and ecosystem functioning and services.

Predicting population-level effects of landscape change depends on identifying factors that influence population connectivity in complex landscapes. However, most putative movement corridors and barriers have not been based on empirical data. In this study, we identify factors that influence connectivity by comparing patterns of genetic similarity among 146 black bears (Ursus americanus), sampled across a 3,000-km 2 study area in northern Idaho, with 110 landscape-resistance hypotheses. Genetic similarities were based on the pairwise percentage dissimilarity among all individuals based on nine microsatellite loci (average expected ). heterozygosity p 0.79 Landscape-resistance hypotheses describe a range of potential relationships between movement cost and land cover, slope, elevation, roads, Euclidean distance, and a putative movement barrier. These hypotheses were divided into seven organizational models in which the influences of barriers, distance, and landscape features were statistically separated using partial Mantel tests. Only one of the competing organizational models was fully supported: patterns of genetic structure are primarily related to landscape gradients of land cover and elevation. The alternative landscape models, isolation by barriers and isolation by distance, are not supported. In this black bear population, gene flow is facilitated by contiguous forest cover at middle elevations.

Due to technical and budget limitations, remote sensing instruments trade spatial resolution and swath width. As a result not one sensor provides both high spatial resolution and high temporal resolution. However, the ability to monitor seasonal landscape changes at fine resolution is urgently needed for global change science. One approach is to "blend" the radiometry from daily, global data (e.g. MODIS, MERIS, SPOT-Vegetation) with data from high-resolution sensors with less frequent coverage (e.g. Landsat, CBERS, ResourceSat). Unfortunately, existing algorithms for blending multi-source data have some shortcomings, particularly in accurately predicting the surface reflectance of heterogeneous landscapes. This study has developed an enhanced spatial and temporal adaptive reflectance fusion model (ESTARFM) based on the existing STARFM algorithm, and has tested it with both simulated and actual satellite data. Results show that ESTARFM improves the accuracy of predicted fine-resolution reflectance, especially for heterogeneous landscapes, and preserves spatial details. Taking the NIR band as an example, for homogeneous regions the prediction of the ESTARFM is slightly better than the STARFM (average absolute difference [AAD] 0.0106 vs. 0.0129 reflectance units). But for a complex, heterogeneous landscape, the prediction accuracy of ESTARFM is improved even more compared with STARFM (AAD 0.0135 vs. 0.0194). This improved fusion algorithm will support new investigations into how global landscapes are changing across both seasonal and interannual timescales.

1] While most land models developed for use with climate models represent vegetation as discrete biomes, this is, at least for mixed life-form biomes, inconsistent with the leaf-level and whole-plant physiological parameterizations needed to couple these biogeophysical models with biogeochemical and ecosystem dynamics models. In this paper, we present simulations with the National Center for Atmospheric Research land surface model (NCAR LSM) that examined the effect of representing vegetation as patches of plant functional types (PFTs) that coexist within a model grid cell. This approach is consistent with ecological theory and models and allows for unified treatment of vegetation in climate and ecosystem models. In the standard NCAR LSM the PFT composition and leaf area for each grid cell are obtained by classifying grid cells as 1 of 28 possible biomes. Here, we develop a data set from 1-km satellite data that provides each model grid cell a unique PFT composition and leaf area for each PFT. Global simulations at 3°Â 3°s patial resolution showed that ground temperature, ground evaporation, and northern high-latitude winter albedo exhibited direct responses to these landscape changes, which led to indirect effects such as in soil moisture and sensible and latent heat fluxes. Additional simulations at 2°Â 2°a nd 1°Â 1°spatial resolution showed that low-resolution simulations masked landscape heterogeneity in both approaches but the satellite-based, continuous representation of vegetation reduced model sensitivity to resolution. It is argued that the use of spatially continuous distributions of coexisting PFTs is a necessary step to link climate and ecosystem models. INDEX TERMS: 0315 Atmospheric Composition and Structure: Biosphere/atmosphere interactions

Land-cover and land-use (LCLU) change was quantified for the last 35 years within and in the vicinity of a fast growing city in Mexico, using rectified aerial photographs and geographic information systems (GIS). LCLU change was projected for the next 20 years using Markov chains ...

There is a lack of information on the environmental effects of urban change and the dynamics of greenspace. Such information is essential for a better understanding of the sustainability of urban development processes, both planned and unplanned. We therefore investigated the changes in land use and land cover of 11 residential areas in Merseyside, UK, using aerial photographs taken in 1975 and 2000. We then modeled how these changes would alter three important environmental parameters: surface temperature, runoff of rainfall, and greenspace diversity. These changes were then related to the socio-economic status of the areas, as measured by an index of multiple deprivation. The comparisons revealed a loss of greenspace in all 11 case study sites Overall, the more affluent, low density areas lost more greenspace, especially of tree cover. A major cause was infill development whereby gardens were built over. However, greenspace was also lost in already densely built-up, deprived areas due to the reuse of derelict land. As a consequence, the models used in this study predicted negative environmental impacts for all areas. The results emphasize the need to critically review concepts such as urban densification and give more weight to the preservation and management of urban greenspaces.

In this paper we test the hypothesis that landscape changes in a region of Northern Portugal (Minho) in the last 40 years could be predicted from socioeconomic and political history. The major predicted changes were related to agricultural abandonment and afforestation. We further predicted that these changes contributed to increased fire risk. Analysis of aerial photography for the years 1958, 1968, 1983 and 1995 in a study area of 3700 ha revealed a significant decline in agricultural areas and low shrublands and an increase in tall shrublands and forests. This represented a 20-40% increase in fuel accumulation at a landscape level, suggesting that the abandonment of farming activities is a major driving force of increasing fire occurrence in the region. With one exception, all the predictions were partly or totally confirmed. This study confirms that socioeconomic factors might explain a significant part of the variation in landscape composition across time, in the Mediterranean region.

This study analyzes urban expansion and spatial restructuring of land use patterns in the Pearl River Delta of south China by using remote sensing and GIS. The region has pioneered the nation in economic development and urbanization process. Tremendous land use changes have been witnessed since the economic reform in 1978. Land use changes over two time periods, 1988-1993 and 1993-1997, are analyzed to demonstrate how enforcing land use policies can influence the direction and magnitude of landscape change. The adoption of a market economy has resulted in the internal restructuring of agricultural land use from traditional paddy production to more diversified agricultural activities, such as growing cash crops, fruits and aquaculture. Spatial dependency of land use changes and variations of land development can be identified between the eastern development corridor and the western development corridor. The measurement of spatial patterns is accomplished by using the indicators of compactness index and entropy. This study provides new evidence with spatial details about the uneven land development in the Pearl River Delta.

In most parts of the world, land-use/land cover can be considered an interface between natural conditions and anthropogenic influence. Indicators are being sought which reflect landscape conditions, pressures and related societal responses. Landscape metrics, which are based on the number, size, shape and arrangement of patches of different land-use/land cover types, are used-together with areal statistics-to quantify landscape structure and composition.The applicability of landscape metrics for landscape monitoring has been investigated in a 700 km2 test region in eastern Germany, where open cast coal mining has caused far reaching land-use changes in the course of this century. Time series of maps (1912–2020) have been elaborated from various data sources (topographic maps, aerial photography, satellite images, prospective planning material). Landscape metrics have been calculated for the entire test region and for ecologically defined subregions at the landscape, class and patch level.The results are presented and methodological issues are addressed, namely the impact of scale, spatial and temporal resolution on the interpretability of landscape metrics. Critical issues are:the application of remote sensing methods, which is a pre-requisite for the area-wide monitoring of land-use change;standardised data processing techniques, which are vital for the spatial and temporal comparability of results;the selection of a manageable set of indicators which embraces the structural properties of landscapes;the choice of appropriate spatial units which allow for an integration of landscape indicators (which tend to relate to cross-border phenomena) and socio-economic indicators (which are usually available for administrative entities or areas).

Increasingly, different functions must be integrated simultaneously in the Danish countryside, demanding a common effort of planners, decision-makers, researchers, and stakeholders. The study proposes a transdisciplinary method that combines scenario technique, photorealistic visualisation, and stakeholder participation to identify the interests of stakeholders in the future countryside. Photorealistic visualised landscape scenarios were used to discuss future options for a rural area in southern Denmark in a meeting with stakeholders and representatives from planning and administration. By focusing on one out of four monofunctional land uses-industrial farming, recreation and tourism, nature conservation, and residential expansion-future extreme scenarios were created. Scenario visualisation by photorealistic design techniques proved to be a helpful tool for researchers in communicating the proposed landscape changes to stakeholders. Interests of stakeholders were quite varied, with strong support for measures to improve environmental quality. Stakeholders lacked trust in planning authorities and were not used to reflect about the future of their home areas. Landscape researchers can contribute to rural planning by improving communication among planners, decision-makers, and stakeholders.

This paper describes some features in the changing landscape of activities intended to improve both quality and access in science, mathematics, engineering, and technology (SMET) undergraduate education. Observations are offered from the viewpoint afforded by my work-broadly over the last 10 years-both as a researcher, and as an evaluator for projects related to the improvement of undergraduate SMET education. Over that period, I have watched the landscape change-some issues, at first prominent, have diminished in importance; some are emergent; and yet others lie on the horizon. I have also observed that actions in pursuit of various reform goals reflect a variety of theories about how change can be accomplished that are not necessarily complementary. This short history of shifts in the focus of our efforts, and in our beliefs about how they may be achieved, is offered as a framework for discussion of these nationwide endeavors and as an aid in considering next steps. C 2001 John Wiley & Sons, Inc. Sci Ed 86:79 -105, 2001.

Paraglacial geomorphology is the study of earth-surface processes, sediments, landforms, landsystems and landscapes that are directly conditioned by former glaciation and deglaciation. The withdrawal of glacier ice exposes landscapes that are in an unstable or metastable state, and consequently liable to modification, erosion and sediment release at rates greatly exceeding background denudation rates. This paper (1) reviews research on paraglacial processes, landforms and landscape change in a range of geomorphological settings; (2) explores the importance of paraglacial landscape modification and sediment recycling as a component of alternating glacial/nonglacial landscape evolution; (3) assesses the nature and significance of paraglacial facies in Quaternary stratigraphic sequences; and (4) develops a general model of the sequence of paraglacial landscape modification and the changing nature of paraglacial landsystems. Six paraglacial landsystems are identified: rock slopes, drift-mantled slopes, glacier forelands, and alluvial, lacustrine and coastal systems. Each contains a wide range of paraglacial landforms and sediment facies. Collectively these landforms and sediments (e.g. talus accumulations, debris cones, alluvial fans, valley fills, deltas and coastal barrier structures) can be conceptualised as storage components of an interrupted sediment cascade with four primary sources (rockwalls, drift-mantled slopes, valley-floor glacigenic deposits and coastal glacigenic deposits) and four terminal sediment sinks (alluvial valley-fill deposits, lacustrine deposits, coastal/ nearshore deposits and shelf/offshore deposits). Paraglacial sediment stores and sinks may form major sources of readily erodible sediment during the early stages of glacial cycles, leading to high rates of sediment transport during periods of glacier or ice-sheet expansion. Probably because of the limited preservation potential of paraglacial sediments that were subsequently overrun by glacier ice, identification of paraglacial facies in both terrestrial and marine settings has been almost exclusively limited to sequences that postdate the Last Glacial Maximum. The unifying concept of paraglacial geomorphology is that of glacially conditioned sediment availability. Relaxation of landscape elements to nonglacial conditions operates over timescales of 10 1->10 4 years, and is conditioned by both process and spatial scale. Rate of sediment reworking can be described by an exhaustion model. In the case of primary reworking of glacigenic sediment, the rate of reworking declines approximately exponentially through time, though extrinsic perturbation may rejuvenate paraglacial sediment flux long after termination of the initial period of paraglacial adjustment. Landscape-scale (particularly alluvial and coastal) systems may exhibit intrinsically complex responses due to reworking of secondary paraglacial sediment stores. The long relaxation time of such systems implies that many areas deglaciated in the Late Pleistocene or Early Holocene have still not fully adjusted (in terms of sediment supply) to nonglacial conditions.

Landscape change associated with urbanization poses major challenges to aquatic ecosystems. Extensive studies have shown that the composition of land cover within a watershed can account for much of the variability in water quality and stream ecological conditions. While several studies have addressed the relationship between watershed urbanization and biotic integrity in streams, few have directly addressed the question of how urban patterns influence ecological conditions. These studies typically correlate changes in ecological conditions with simple aggregated measures of urbanization (e.g., human population density or percent impervious surface). We develop an empirical study of the impact of urban development patterns on stream ecological conditions in 42 sub-basins in the Puget Sound lowland region on a gradient of urbanization. We hypothesize that ecological conditions in urbanizing landscapes are influenced through biophysical changes by four urban pattern variables: land use intensity, land cover composition, landscape configuration, and connectivity of the impervious area. Using community measures of benthic macroinvertebrates as indicators of in-stream biotic integrity we examined the relationships between urban development patterns and ecological conditions in these basins. Significant statistical relationships were found between landscape patterns-both amount and configuration of impervious area and forest land-and biotic integrity of streams suggesting that patterns of urban development matter to aquatic ecosystems.

Europe's rural areas are expected to witness massive and rapid changes in land use due to changes in demography, global trade, technology and enlargement of the European Union. Changes in demand for agricultural products and agrarian production structure are likely to have a large impact on landscape quality and the value of natural areas. Most studies address these changes either from a macro-economic perspective focusing on changes in the agricultural sector or from a local perspective by analyzing recent changes in landscapes for small case studies. This paper describes a methodology in which a series of models has been used to link global level developments influencing land use to local level impacts. It is argued that such an approach is needed to properly address the processes at different scales that give rise to the land use dynamics in Europe. An extended version of the global economic model (GTAP) and an integrated assessment model (IMAGE) are used to calculate changes in demand for agricultural areas at the country level while a spatially explicit land use change model (CLUE-s) was used to translate these demands to land use patterns at 1 km 2 resolution. The global economic model ensures an appropriate treatment of

Time-lagged responses of biological variables to landscape modifications are widely recognized, but rarely considered in ecological studies. In order to test for the existence of time-lags in the response of trees, small mammals, birds and frogs to changes in fragment area and connectivity, we studied a fragmented and highly dynamic landscape in the Atlantic forest region. We also investigated the biological correlates associated with differential responses among taxonomic groups. Species richness and abundance for four taxonomic groups were measured in 21 secondary forest fragments during the same period (2000)(2001)(2002), following a standardized protocol. Data analyses were based on power regressions and model selection procedures. The model inputs included present and past (1962, 1981) fragment areas and connectivity, as well as observed changes in these parameters. Although past landscape structure was particularly relevant for trees, all taxonomic groups (except small mammals) were affected by landscape dynamics, exhibiting a time-lagged response. Furthermore, fragment area was more important for species groups with lower dispersal capacity, while species with higher dispersal ability had stronger responses to connectivity measures. Although these secondary forest fragments still maintain a large fraction of their original biodiversity, the delay in biological response combined with high rates of deforestation and fast forest regeneration imply in a reduction in the average age of the forest. This also indicates that future species losses are likely, especially those that are more strictly-forest dwellers. Conservation actions should be implemented to reduce species extinction, to maintain old-growth forests and to favour the regeneration process. Our results demonstrate that landscape history can strongly affect the present distribution pattern of species in fragmented landscapes, and should be considered in conservation planning.

Detailed understanding of landscape changes along the urban-rural gradient provides a useful tool to compare the structural and functional differences of landscape patches at different orientations. Although several case studies have been conducted confirming the efficacy of this approach, integrating temporal data with gradient analysis is still rarely used in practice. In this study, a combination of remote sensing images, landscape metrics and gradient analysis are employed to analyze and compare both the spatial and temporal dynamics of urban sprawl in Guangzhou, China. The results show that landscape change in Guangzhou exhibits distinctive spatial differences from the urban center to rural areas, with higher fragmentation at urban fringes or in new urbanizing areas. Due to the complexity of top-down constraints and local interactions, Guangzhou exhibits a more complex, dynamic, multidimensional configuration of urban sprawl that is different from other cities in China. Urban area expanded towards the north and south areas due to the increased population and rapid economic development. Property market forces and government policy led to the rapid growth towards the southern areas. The study also confirms the hypothesis of diffusion-coalescence urban dynamics model in the process of urbanization. It demonstrates that in order to reveal the complexity of landscape pattern, temporal data are needed to capture the baseline as well as the spatio-temporal dynamics of landscape changes along the gradient. Combining temporal data with gradient analysis can characterize the complex spatial pattern of urbanization in Guangzhou well.

As landscapes change continuously in a more or less chaotic way, the concept of sustainable landscapes could be viewed as a utopian goal. New landscapes emerge with changing life-styles. Decision making for landscape planning, conservation and management use ...

Social and economic considerations are among the most important drivers of landscape change, yet few studies have addressed economic and environmental influences on landscape structure, and how land ownership may affect landscape dynamics. Watersheds in the Olympic Peninsula, Washington, and the southern Appalachian highlands of western North Carolina were studied to address two questions: (1) Does landscape pattern vary among federal, state, and private lands? (2) Do land-cover changes differ among owners, and if so, what variables explain the propensity of land to undergo change on federal, state, and private lands? Landscape changes were studied between 1975 and 1991 by using spatial databases and a time series of remotely sensed imagery. Differences in landscape pattern were observed between the two study regions and between different categories of land ownership. The proportion of the landscape in forest cover was greatest in the southern Appalachians for both U.S. National Forest and private lands, compared to any landownership category on the Olympic Peninsula. Greater variability in landscape structure through time and between ownership categories was observed on the Olympic Peninsula. On the Olympic Peninsula, landscape patterns did not differ substantially between commercial forest and state Department of Natural Resources lands, both of which are managed for timber, but differed between U.S. National Forest and noncommercial private land ownerships. In both regions, private lands contained less forest cover but a greater number of small forest patches than did public lands.

Many species of vertebrates require multiple habitats to obtain dierent resources at dierent stages of their life-cycles. Use of habitat mosaics takes place on a variety of spatial and temporal scales, from a daily requirement for adjacent habitats to seasonal use of geographically separated environments. Mosaics of habitats are also required in some species to allow ontogenetic habitat shifts, while in others each sex may have speci®c requirements that are met by dierent habitats. The extent and nature of animal movements are key (but generally poorly known) factors aecting the vulnerability of species to landscape change. The requirement by many species for multiple habitats suggests that their conservation will be most eective in a mosaic environment and that protection of certain high pro®le habitats alone, such as rainforest, will be insucient to achieve conservation goals. Management regimes that result in homogenization of habitats should be avoided. Priority should be given to research that identi®es the extent to which species can locate habitat mosaics, at dierent spatial scales and arrangements, in modi®ed environments.

The rural landscapes of Europe are in both a homogenisation and a fragmentations process. Regional differences are disappearing due to the dominating equalising impact of the worldwide market. If regional differences are not maintained and protected then the cultural landscapes of Europe and their biological diversity will decline and only remnants will remain. Models on agricultural management and data on landscape changes from all Europe con®rm this. Regional differences have to be maintained through conscious environmental and ecological planning. Concepts for this have been developed in all countries in Europe, such as the ecostabilisation concept and the concept of ecological networks. Nature management by farmers is more and more accepted. Landscape planners should be aware of their changing role from designer towards negotiator with the actors in the landscape with different landscape functions and planning tasks in mind. #

The southeastern United States (SE-US) has undergone one of the highest rates of landscape changes in the country due to changing demographics and land use practices over the last few decades. Increasing evidence indicates that these changes have impacted mesoscale weather patterns, biodiversity and water resources. Since the Southeast has one of the highest rates of land productivity in the nation, it is important to monitor the effects of such changes regularly. Here, we propose a remote sensing based methodology to estimate regional impacts of urban land development on ecosystem structure and function. As an indicator of ecosystem functioning, we chose net primary productivity (NPP), which is now routinely estimated from the MODerate resolution Imaging Spectroradiometer (MODIS) data. We used the MODIS data, a 1992 Landsat-based land cover map and nighttime data derived from the Defense Meteorological Satellite Program's Operational Linescan System (DMSP/OLS) for the years 1992/1993 and 2000 to estimate the extent of urban development and its impact on NPP. The analysis based on the nighttime data indicated that in 1992/1993, urban areas amounted to 4.5% of the total land surface of the region. In the year 2000, the nighttime data showed an increase in urban development for the southeastern United States of 1.9%. Estimates derived from the MODIS data indicated that land cover changes due to urban development that took place during the 1992 -2000 period reduced annual NPP of the southeastern United States by 0.4%. Despite the uncertainties in sensor fusion and the coarse resolution of the data used in this study, results show that the combination of MODIS products such as NPP with nighttime data could provide rapid assessment of urban land cover changes and their impacts on regional ecosystem resources. D

Gene flow is a key factor in the spatial genetic structure in spatially distributed species. Evolutionary biologists interested in microevolutionary processess and conservation biologists interested in the impact of landscape change require a method that measures the real time process of gene movement. We present a novel two-generation (parent-offspring) approach to the study of genetic structure (TwoGener) that allows us to quantify heterogeneity among the male gamete pools sampled by maternal trees scattered across the landscape and to estimate mean pollination distance and effective neighborhood size. First, we describe the model's elements: genetic distance matrices to estimate intergametic distances, molecular analysis of variance to determine whether pollen profiles differ among mothers, and optimal sampling considerations. Second, we evaluate the model's effectiveness by simulating spatially distributed populations. Spatial heterogeneity in male gametes can be estimated by ⌽ FT , a male gametic analogue of Wright's F ST and an inverse function of mean pollination distance. We illustrate TwoGener in cases where the male gamete can be categorically or ambiguously determined. This approach does not require the high level of genetic resolution needed by parentage analysis, but the ambiguous case is vulnerable to bias in the absence of adequate genetic resolution. Finally, we apply TwoGener to an empirical study of Quercus alba in Missouri Ozark forests. We find that ⌽ FT ϭ 0.06, translating into about eight effective pollen donors per female and an effective pollination neighborhood as a circle of radius about 17 m. Effective pollen movement in Q. alba is more restricted than previously realized, even though pollen is capable of moving large distances. This case study illustrates that, with a modest investment in field survey and laboratory analysis, the TwoGener approach permits inferences about landscape-level gene movements.

Land use has changed dramatically over the last 30-40 years throughout the Mediterranean. Much of this change has been driven by shifts in agricultural and socio-economic policy. This paper explores landscape dynamics in the SPA 'Encinares del río Alberche y Cofio' Central Spain between 1984 and 1999 in an area of approximately 83,000 ha. Categorical land cover maps, derived from three (1984, 1991 and 1999) remotely sensed Landsat images, are analyzed using a suite of landscape pattern metrics, and a simple transition matrix model of landscape change is developed. As with other landscapes in the Mediterranean a key trend is that of the abandonment of agricultural land and its subsequent succession to scrubland and woodland. Although there were significant composition changes in the landscape over the study period configurational changes are less evident. The transition matrix model suggests that there were differences in landscape dynamics between 1984-1991 and 1991-1999-most importantly an increase in the rate of land abandonment is evident. The model predicts a steady state landscape containing a higher abundance of scrubland and woodland, and a corresponding decline in pastureland and cropland. Finally, the underlying socio-economic and other drivers of landscape change in the Encinares del río Alberche y Cofio and some of the implications of recent changes are discussed in terms of increased wildfire risk. Sustainable management of landscapes to protect biodiversity requires the type of study described here. A necessary pre-requisite of such management activities or planning is an assessment of changes in landscape pattern and process, the social and economic pressures driving them, and their possible effects on ecosystem structure and function.

Agricultural dynamics and associated changes in the structure of habitat patches affect species composition and distribution in the landscape. Land-use, landscape changes and vegetation changes of weeds were analysed in a 4 km 2 area in Central Germany (Saxony-Anhalt) from 1953 to 2000. This period includes the collectivisation (1952)(1953)(1954)(1955)(1956)(1957)(1958)(1959)(1960)(1961)(1962)(1963)(1964)(1965)(1966)(1967)(1968), the agricultural industrialisation and the privatisation of agricultural land following the political changes in East Germany in 1990. For the analyses, historic and current aerial photographs and vegetation data were used. Landscape indices and the average amount of mineral fertilizers were used as indicators for landscape structure and land-use intensity. Intensification of agriculture and the collectivisation in East Germany in the fifties and sixties led to a decline of the spatial heterogeneity of the landscape matrix (arable fields). The average number and cover of weed species, especially archaeophytes, decreased significantly since 1957. However, the total number of weed species increased. There was a remarkably high number of species with an average cover below 0.05%, called ''chance'' species in 2000. Out of 17 tested landscape indices only mean patch size and mean patch fractal dimension were significantly correlated with the average number of weed species. The average amount of the mineral fertilizer potash used as land-use intensity indicator was significantly negatively correlated with the total number of weed species. However, there was an increase in the number of farms after 1990 without changes in landscape structure and arable weed vegetation. The results suggest that structural variability of the landscape and habitat quality are the principal correlates of plant species diversity. # 2005 Published by Elsevier B.V.

This aim of this paper is to present the objectives and scope of an evolutionary approach to economic geography. We argue that the goal is not only to utilise the concepts and ideas from evolutionary economics (and evolutionary thinking more broadly) to help interpret and explain how the economic landscape changes over historical time, but also to reveal how situating the economy in space adds to our understanding of the processes that drive economic evolution, that is to say, to demonstrate how geography matters in determining the nature and trajectory of evolution of the economic system. We will argue that evolutionary economic geography is concerned with the spatialities of economic novelty; with how the spatial structures of the economy emerge from the micro-behaviours of economic agents; with how, in the absence of central coordination or direction, the economic landscape exhibits self-organisation; and with how the processes of path creation and path dependence interact to shape geographies of economic development and transformation, and why and how such processes may themselves be place dependent. Economic transformation proceeds differently in different places, and the mechanisms involved neither originate nor operate evenly across space. Our concern is both with the ways in which the forces making for economic change, adaptation and novelty shape and reshape the geographies of wealth creation, work and welfare, and with how the spatial structures and features so produced themselves feed back to influence the forces driving economic evolution. In the final part, we summarize a number of papers that have contributed to evolutionary economic geography, and which will be published in The Handbook on Evolutionary Economic Geography that is edited by the two authors, and forthcoming at Edward Elgar.

Landscape-level variables operating at multiple spatial scales likely influence wetland amphibian assemblages but have not been investigated in detail. We examined the significance of habitat loss and fragmentation. as well as selected within-wetland conditions. affecting amphibian assemblages in twenryone glacial marshes. Wetlands were located within urban and agricultural regions of central and southwestern Minnesota, USA and were distributed across two ecoregions: tallgrass prairie and northern hardwood forest. We surveyed amphibian assemblages and used a geographic information system to quantify land-use variables at three scales: 500. 1000. and 2500 m. Ten species of amphibians were detected. the most abundant being Rana pipiens. Ambysroma tigrinum. and Bufa americanus. Amphibian species richness was lower with greater wetland isolation and road density at aU spatial scales in both ecoregions. Amphibian species richness also had a negative relationship with the proportion of urban land-use at alJ spatial scales in the hardwood forest ecoregion. and species richness was greater in wetlands with fish and AmDvstoma tigrinum. These biotic relationships are less consistent and more difficult to inrerpret than are land-use relationships. The data presented here suggest that decreases in landscape connectivity via fragmenration and habitat loss can affect amphibian assemblages. and reversing those landscape changes should be an important part of a regional conservation strategy.

The Mediterranean area is one of the most significantly altered hotspots on Earth, since it has been intensively affected by human activity for millennia. As a result, only 4.7% of its primary vegetation remained unaltered and the landscape has been repeatedly transformed. In this paper, we aimed at detecting both the direction and the rate of landscape change focusing on the effects of human activity on the environmental heterogeneity of the Mediterranean landscape under study. In particular, we carried out an analysis of landscape changes occurred in a Mediterranean area from 1954 to 2000, by means of a comparative examination of a historical and a recent land use map. Land use changes have been quantified by landscape metrics coupled with topographical information. Results underline: i) a general homogenisation of the landscape, ii) modification of the arrangements for exploitation of the territory, particularly in the plain areas, iii) a trend of recovery of the territory by the forest to the detriment of semi-natural and agricultural areas in hilly and mountain parts. The analysis of the complex phenomena related to land use changes can be a useful tool to define effective strategies for natural resources management and biodiversity conservation.

There is a great concern about the loss of biodiversity that calls for more nature protection. Unfortunately, the funding available for conservation is limited, and often a compromise is needed between nature protection and economic interests. Reserve selection algorithms are optimization techniques that concentrate on identifying a set of reserves that represents biodiversity efficiently. Simple approaches to reserve selection use presence-absence data assuming that if a species occurs in a selected reserve, it will persist there indefinitely.

We examined the impacts of possible future land development patterns on the biodiversity of a landscape. Our landscape data included a remote sensing derived map of the current habitat of the study area and six maps of future habitat distributions resulting from different land development scenarios. Our species data included lists of all bird, mammal, reptile, and amphibian species in the study area, their habitat associations, and area requirements for each. We estimated the area requirements using home ranges, sampled population densities, or genetic area requirements that incorporate dispersal distances. Our measures of biodiversity were species richness and habitat abundance. We calculated habitat abundance in two ways. First, we computed the total habitat area for each species in each landscape. Second, we calculated the number of habitat units for each species in each landscape by dividing the size of each habitat patch in the landscape by the area requirement and summing over all patches. Species richness was based on presence of habitat. Species became extinct in the landscape if they had no habitat area or no habitat units, respectively. We then computed ratios of habitat abundance in each future landscape to habitat abundance in the present for each species. We also computed the ratio of future to present species richness. We then calculated summary statistics across all species. Species richness changed little from present to future. There were distinctly greater risks to habitat abundance in landscapes that extrapolated from present trends or zoning patterns, however, as opposed to landscapes in which land development activities followed more constrained patterns. These results were stable when tested using Monte Carlo simulations and sensitivity tests on the area requirements. We conclude that this methodology can begin to discriminate the effects of potential changes in land development on vertebrate biodiversity.

The spatial deconcentration of population during the 20th century and the resulting expansion of human settlements has been a significant cause of anthropogenic landscape change in the United States and many other countries. In the seven-state North Central Region, as in other regions of the US, changing human settlement patterns are most prominent at the outlying fringe of metropolitan areas and in rural regions with attractive recreational and aesthetic amenities. This process of growth and change has profound implications for the ecology of the region that will require the reformulation of resource management policies.

This paper reviews our current understanding of Quaternary climate and landscape changes in the desert areas of northern China, a key portion of the middle-latitude drylands on Earth. Combining earlier studies with our recent research and experience, we offer a comprehensive picture of the state of Chinese deserts during the Quaternary and, in the interest of enhancing future research, identify knowledge gaps and areas of uncertainty.

Two case studies of cultural landscapes in Southern Germany were conducted to develop appropriate techniques for quantifying and analysing the landscape change since 1850. Methods were derived from geographical landscape change analysis, based on cadastral maps and land registers, and were rendered at a land plot level by the use of GIS. The database for the diachronic GIS, especially cadastral maps and land plot records, are discussed in detail. This study emphasizes that an approach based on a land plot level and using a land record-based GIS provides valuable results relevant for planning processes and nature conservation in changing cultural landscapes.

The idea that landscape has been created by human activities on a biophysical basis allows for clear causeeffect reasoning. However, landscape planning and management practice learns that it is impossible to neglect the social perception of landscape, i.e. the ways people think about nature and landscape. It is the result of social research and human sciences of the last decade that a differentiation in views of nature and landscape can be identified in the different groups of social actors in the landscape. Case studies from France and the Netherlands show a marked change in values attributed to nature and landscape in the end of the last century. Social demand for landscape is growing and a shift from a functional image of nature and landscape to a more hedonistic image like the Arcadian and wilderness images has taken place. Comparing the Netherlands with France and rural with urban inhabitants, the influence of urbanisation is evident in this process. It is further shown that images of nature vary considerably between for example farmers, urban residents, hunters and conservationists. The way people perceive landscape seems determined by their functional ties with the landscape and the social praxis in which they encounter the landscape. It is concluded that the concept of landscape is nearer to the lifeworld of people than the abstract notions of nature and biodiversity. This implies a big challenge both for national and international landscape policies and for local landscape management initiatives to be developed, taking into due consideration both the material and immaterial nature of landscape.

The objective of this study is to evaluate the relationship between the response (rj) of airborne P-band Synthetic Aperture Radar (SAR) polarimetric data versus biomass values of primary forest and secondary succession. To ensure that different landscapes of ''Terra firme'' tropical forest of the Brazilian Amazon were represented, a test-site was selected in the lower Tapajós river region (Pará State). The microwave signals from the P-band polarimetric images were related to the aboveground biomass data by statistical regression models (logarithmic and polynomial functions). In the field survey, physiognomic and structural aspects of primary forest and regrowth were collected and afterwards the biomass was estimated using allometric equations based on dendrometric parameters. As an example of the potential use of P-band polarimetric images, they were classified by a contextual classifier (ICM), whose thematic stratification of land use/ land cover was associated with biomass class intervals for mapping purposes. The main objective of this P-band experiment is to improve this tool for regional mapping of Amazon landscape changes, due to the growing rate of land use occupation. D