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1.
Landscapes surrounding parks in most of the developing world, while still containing considerable biodiversity, also have rapidly growing human populations and associated agricultural development. Since the establishment of Kibale National Park first as a Crown Forest Reserve in 1932 and later as a park in 1993 in western Uganda, most access and resource extraction has been prohibited. The park has become nearly a complete island of forested land cover surrounded by intensive small-scale agriculture and some large-scale tea plantations, along with a network of wetland and forest patches. As the population grows outside the park and land becomes more scarce, remaining forests and wetlands are being used more intensively for material resources (e.g., fuelwood, building poles) and converted to other land uses (e.g., pasture, agriculture). This study uses both discrete and continuous data analyses of satellite imagery to examine these diminishing resource bases at the landscape level placing the results within the social context of conservation and parks. Findings reveal that the park boundaries have remained fairly intact whereas, the landscape surrounding the park has become increasingly fragmented. From a landscape perspective, while the park has indeed maintained its forest cover, it has become increasingly islandized with wetland and forest patches in the surrounding landscape becoming smaller in number and size. Those that have survived are now more isolated and even lower productivity than in 1984, which may be a precursor to their eventual loss in this landscape.  相似文献   

2.
Development in biodiversity rich areas is of global concern. While development may lead to socioeconomic benefits, this often comes concomitant with biodiversity loss and deforestation. Biodiversity rich areas present the opportunity for both improvements in socioeconomic conditions and conservation; however numerous challenges exist. Costa Rica’s Manuel Antonio National Park presents an ideal case study to investigate the balance between alternative forms of development which have contrasting environmental impacts. The Manuel Antonio region is a highly dynamic landscape experiencing deforestation, from agriculture, cattle ranching and oil palm plantations; and also reforestation from abandonment of land holdings and nature oriented tourism. Landscape dynamics are closely intertwined with the livelihoods and perspectives on biodiversity conservation of local communities, determining ecological sustainability. We use an analysis combining multi-temporal remote sensing of land cover dynamics from 1985 to 2008 with questionnaire data from local families on their socioeconomic status, perspectives on conservation, and perceived changes in local wildlife populations. Our results show that, while regeneration occurred and forest fragmentation in the area decreased from 1985 to 2008, Manuel Antonio National Park is rapidly becoming isolated. Decreasing ecological connectivity is related to the rapid expansion of oil palm plantations adjacent to the park and throughout the lowland areas. Perceived decreases in wildlife abundance and compositional change are evident throughout the area, with local communities attributing this primarily to illegal hunting activities. Nature based tourism in the area presents an effective strategy for conservation, including reductions in hunting, through increased valuation of biodiversity and protected areas, and socioeconomic advantages. However, without urgent efforts to limit deforestation and preserve the remaining forested corridor connecting the park to core primary forest, the ability to maintain biodiversity in the park will be reduced.  相似文献   

3.
We used an integrated modeling approach to simulate future land cover and predict the effects of future urban development and land cover on avian diversity in the Central Puget Sound region of Washington State, USA. We parameterized and applied a land cover change model (LCCM) that used output from a microsimulation model of urban development, UrbanSim, and biophysical site and landscape characteristics to simulate land cover 28 years into the future. We used 1991, 1995, and 1999 Landsat TM-derived land cover data and three different spatial partitions of our study area to develop six different estimations of the LCCM. We validated model simulations with 2002 land cover. We combined UrbanSim land use outputs and LCCM simulations to predict changes in avian species richness. Results indicate that landscape composition and configuration were important in explaining land cover change as well as avian species response to landscape change. Over the next 28 years, urban land cover was predicted to increase at the expense of agriculture and deciduous and mixed lowland forests. Land cover changes were predicted to reduce the total number of avian species, with losses primarily in native forest specialists and gains in common synanthropic species such as the American Crow (Corvus brachyrhynchos). The integrated modeling framework we present has potential applications in urban and natural resource planning and management and in assessing of the effects of policies on land development, land cover, and avian biodiversity.  相似文献   

4.

Context

Landscape modification is an important driver of biodiversity declines, yet we lack insight into how ongoing landscape change and legacies of historical land use together shape biodiversity.

Objectives

We examined how a history of agricultural land use and current forest fragmentation influence the abundance of red-backed salamanders (Plethodon cinereus). We hypothesized that historical agriculture and fragmentation cause changes in habitat quality and landscape structure that limit abundance.

Methods

We measured salamander abundance at 95 forested sites in New York, USA, and we determined whether sites were agricultural fields within the last five decades. We used a structural equation model to estimate relationships between historical agriculture and salamander abundance mediated by changes in forest vegetation, microclimate, and landscape structure.

Results

Historical agriculture affected salamander abundance by altering forest vegetation at a local scale and forest cover at a landscape scale. Abundance was lowest at post-agricultural sites with low woody vegetation, leaf litter depth, and canopy cover. Post-agricultural sites had limited forest cover in the surrounding landscape historically, and salamander abundance was positively related to historical forest cover, suggesting that connectivity to source populations affects colonization of regenerating forests. Abundance was also negatively related to current forest fragmentation.

Conclusions

Historical land use can have legacy effects on animal abundance on par with effects of ongoing landscape change. We showed that associations between animal abundance and historical land use can be driven by altered site conditions and surrounding habitat area, indicating that restoration efforts should consider local site conditions and landscape context.
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5.
This study analyzes forest change in an area of Nepal that signifies a delicate balance between sustaining the needs and livelihood of a sizable human population dependent on forest products, and an effort to protect important wildlife and other natural resources. The study area, a portion of the Chitwan valley district of Nepal, represents what may be becoming a common institutional mosaic in many countries of the world who have a population reliant on forest products for their livelihood: (1) a national park; (2) a designated park buffer involving participatory forest management programs; (3) scattered patches of designated community forest; and (4) large areas of adjacent landscape made up of mostly private landholdings under agricultural practices. Utilizing Landsat images from 1989 and 2000, we analyze land cover change in each of these management zones using landscape ecology metrics and quantifying proportional distributions of land cover categories. Our results show significant differences in terms of land cover dynamics and landscape spatial pattern between these land ownership classes. These findings indicate that community-based institutions (participatory management programs in the park buffer and the designated community forests) are capable of halting or even reversing trends in deforestation and forest fragmentation.  相似文献   

6.
Cities continue to grow worldwide, and the highly modified urban landscape becomes an inhospitable environment for many species because the natural vegetation cover is commonly fragmented, and the remnants are often isolated. Protected Areas (PAs) located surrounding or within urban areas may not achieve their goal of protecting local or regional biodiversity. Thus, an urban ecological network is essential to support their PAs. Thus, this study aimed at assessing the PAs connectivity in an urban landscape in Brazil and understanding whether urban forest fragments can support an urban ecological network. Besides spatial models based on functional connectivity and graph theory, we used participatory techniques to design the resistance surface and the least-cost paths (LCPs) for Atlantic Forest birds. The results showed critical paths (LCPs), important areas for restoration programs for improving PAs connectivity, and essential forest fragments for conservation and restoration. Although the landscape has a forest structure with 1873 forest fragments and 516 links through which the LCPs were structured, most forest fragments and LCPs cannot provide the necessary support for the PAs connectivity. The current ecological network is dependent on forest fragments neighboring (outside PAs) and the flux dispersions occurred mainly in the peri-urban areas. Riparian zones and anthropic grasslands also showed importance for the PAs connectivity. We identified only 28 forest fragments spatially connected, presenting several sizes, and located near large forest areas, relevant PAs, and riparian zones. Six of these forest fragments, smaller than ten hectares and strategically located in the urban matrix, were indicated for restoration actions. The current low connectivity among PAs brings the importance of native vegetation restoration in the riparian zone and anthropic grassland and the importance of the periurban areas to promote biodiversity connectivity in the urban landscape.  相似文献   

7.
为探索国家森林公园建设发展情况并揭示其空间分布规律,本研究采用知识图谱及GIS空间技术对我国国家森林公园的研究进展和空间格局进行了可视化的探索分析.结果 显示:(1)国家森林公园、生态旅游、森林旅游、风景园林、生物多样性、自然保护区、评价、群落结构等是我国森林公园的历史研究热点领域.(2)我国国家森林公园总体呈现东密西疏的空间格局,东北区域及西南区域公园分布较为集中,青海及西藏地区相反.(3)1992-2017年期间国家森林公园的面积得到了更为显著的提升,黑龙江、西藏、新疆、内蒙古4省贡献的面积较多,天津、上海、宁夏、海南4省市对全国国家森林公园建设面积的贡献较小.西部地区国家森林公园的数量有待提升,宁夏、海南2省的国家森林公园总面积有较大理论拓展空间,未来可以加强国家森林公园动态监测评价、森林公园管理制度保障、森林公园建设成效评价、智慧森林公园等方面的研究,以此来推动全国森林公园的全面健康发展.  相似文献   

8.
Context

As agricultural demands for land continues to expand, strategies are urgently needed to balance agricultural production with biodiversity conservation and ecosystem service provision in agricultural landscapes.

Objectives

We used a factorial landscape design to assess the relative contributions of forest proximity and local forest cover to bee diversity and the provision of coffee pollination services.

Methods

We quantified bee diversity and fruit set in 24 sun-grown coffee fields in Southeast Region of Brazil that were selected following a factorial sampling design to test the independent effects of local forest cover (in a radius of 400 m) and proximity to forest fragments. To assess the impact of landscape simplification, we also evaluated local coffee cover.

Results

Bee richness and abundance were higher in the proximity of forest fragments, but only bee abundance decreased when the coffee cover dominated the surrounding landscapes. Coffee fruit set was 16% higher overall with bee visitations compared with bee exclusion and increased to 20% when coffee bushes were near forest fragments, and the coffee cover was low. Surprisingly, local forest cover did not affect the bee community or coffee fruit set.

Conclusion

Our results provide clear evidence that the proximity of coffee crops to forest fragments can affect the abundance and richness of bees visiting the coffee flowers and thereby facilitate the provision of pollination services. The positive association between forest proximity and fruit set reinforces the importance of natural vegetation in enhancing bee diversity and, therefore, in the provision of pollination services. The negative effect of coffee cover on fruit set at the local scale suggests that the service demand can surpass the capacity of pollinators to provide it. These effects were independent of the local forest cover, although all studied landscapes had more than 20% remaining forest cover (within a 2 km radius), which is considered the extinction threshold for Atlantic Forest species. Interspersion of forest fragments and coffee plantations in regions with more than 20% of forest cover left could thus be a useful landscape management target for facilitating pollinator flows to coffee crops and thus for increasing coffee yields.

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9.
Native forests play an important role regarding ecosystem services related to biodiversity, water, and nutrient cycling, and the intensity of those services should be related to the amount, configuration and quality of the forest. However, in highly dynamic landscapes, such as some tropical regions, ecosystem services are potentially affected not only by the present landscape structure, but also by the historical land use. Here we propose a simple methodological framework to evaluate the contribution of past landscape dynamics and present landscape structure in the provision of ecosystem services. We applied this framework to a traditional agricultural landscape from the Brazilian Atlantic Forest hotspot, where natural forests cover has increased from 8 to 16 % in the last 60 years (1962–2008), and where old forests are being reduced while young forests are being regenerated. Forests of different ages, in association with current landscape structure, reveal a mosaic of forest patches under different conditions, implying different abilities to deliver ecosystem services. With the replacement of old-growth forests by young-regenerating forests and a high level of forest fragmentation, less than 1/4 of the current forest cover is able to fully satisfy the ecosystem service demands. To avoid such tendency, government policies should not only focus on increasing forest cover, but also in conserving old-growth forest fragments or increasing forest quality. The proposed methodology allows integrating historical land use and current landscape structure to evaluate ecosystem services provision and can be useful to establish programs of payment for ecosystem services.  相似文献   

10.
We studied habitat selection and breeding success in marked populations of a protected seabird (family Alcidae), the marbled murrelet (Brachyramphus marmoratus), in a relatively intact and a heavily logged old-growth forest landscape in south-western Canada. Murrelets used old-growth fragments either proportionately to their size frequency distribution (intact) or they tended to nest in disproportionately smaller fragments (logged). Multiple regression modelling showed that murrelet distribution could be explained by proximity of nests to landscape features producing biotic and abiotic edge effects. Streams, steeper slopes and lower elevations were selected in both landscapes, probably due to good nesting habitat conditions and easier access to nest sites. In the logged landscape, the murrelets nested closer to recent clearcuts than would be expected. Proximity to the ocean was favoured in the intact area. The models of habitat selection had satisfactory discriminatory ability in both landscapes. Breeding success (probability of nest survival to the middle of the chick rearing period), inferred from nest attendance patterns by radio-tagged parents, was modelled in the logged landscape. Survivorship was greater in areas with recent clearcuts and lower in areas with much regrowth, i.e. it was positively correlated with recent habitat fragmentation. We conclude that marbled murrelets can successfully breed in old-growth forests fragmented by logging.  相似文献   

11.
Land cover and land use changes can have a wide variety of ecological effects, including significant impacts on soils and water quality. In rural areas, even subtle changes in farming practices can affect landscape features and functions, and consequently the environment. Fine-scale analyses have to be performed to better understand the land cover change processes. At the same time, models of land cover change have to be developed in order to anticipate where changes are more likely to occur next. Such predictive information is essential to propose and implement sustainable and efficient environmental policies. Future landscape studies can provide a framework to forecast how land use and land cover changes is likely to react differently to subtle changes. This paper proposes a four step framework to forecast landscape futures at fine scales by coupling scenarios and landscape modelling approaches. This methodology has been tested on two contrasting agricultural landscapes located in the United States and France, to identify possible landscape changes based on forecasting and backcasting agriculture intensification scenarios. Both examples demonstrate that relatively subtle land cover and land use changes can have a large impact on future landscapes. Results highlight how such subtle changes have to be considered in term of quantity, location, and frequency of land use and land cover to appropriately assess environmental impacts on water pollution (France) and soil erosion (US). The results highlight opportunities for improvements in landscape modelling.  相似文献   

12.
This study explores the relationships between an increase in tree cover area (i.e., natural and planted-tree land covers) and changes in forest carbon storage and the potential of a landscape to provide habitat for native floristic biodiversity. Four areas experiencing an increase in tree cover were analyzed. We developed a metric estimating the potential to support native biodiversity based on tree cover type (plantation or natural forests) and the landscape pattern of natural and anthropogenic land covers. We used published estimates for forest and plantation carbon stocks for each region. Focus regions in northwestern Costa Rica, northern Vietnam, southern Chile and highland Ecuador all showed an increase in tree cover area of 390?%, 260?%, 123?% and 418?%, respectively. Landscapes experiencing increases in natural secondary forest also experienced an increase in carbon stored above and below ground, and in the potential to support native floristic biodiversity. Study landscapes in Chile and Ecuador experiencing an expansion of exotic plantations saw their carbon stock decrease along with their potential to support native floristic biodiversity. This study shows that an increase in forest area does not necessarily imply an increased provision of ecosystem services when landscapes are reforesting with monoculture plantations of exotic tree species. Changes in the support of native biodiversity and the carbon stored in pulp rotation plantations, along with other ecosystem services, should be fully considered before implementing reforestation projects.  相似文献   

13.

Context

Forest loss and fragmentation negatively affect biodiversity. However, disturbances in forest canopy resulting from repeated deforestation and reforestation are also likely important drivers of biodiversity, but are overlooked when forest cover change is assessed using a single time interval.

Objectives

We investigated two questions at the nexus of plant diversity and forest cover change dynamics: (1) Do multitemporal forest cover change trajectories explain patterns of plant diversity better than a simple measure of overall forest change? (2) Are specific types of forest cover change trajectories associated with significantly higher or lower levels of diversity?

Methods

We sampled plant biodiversity in forests spanning the Charlotte, NC, region. We derived forest cover change trajectories occurring within nested spatial extents per sample site using a time series of aerial photos from 1938 to 2009, then classified trajectories by spatio-temporal patterns of change. While accounting for landscape and environmental covariates, we assessed the effects of the trajectory classes as compared to net forest cover change on native plant diversity.

Results

Our results indicated that forest stand diversity is best explained by forest change trajectories, while the herb layer is better explained by net forest cover change. Three distinct forest change trajectory classes were found to influence the forest stand and herb layer.

Conclusions

The influence of forest dynamics on biodiversity can be overlooked in analyses that use only net forest cover change. Our results illustrate the utility of assessing how specific trajectories of past land cover change influence biodiversity patterns in the present.
  相似文献   

14.
Plant invasions in the landscape   总被引：3，自引：1，他引：2  
Biological invasions and changes in land-use are two components of global change affecting biodiversity worldwide. There is overriding evidence that invasions can dramatically change the landscape and that particular land-use types facilitate invasions. Still, these issues have not formally percolated into risk analysis of biological invasions, and only recently has the influence of the surrounding landscape on invasive species spread started to be considered. In this paper we review the literature on the influence of the surrounding landscape on the local level of plant invasions (i.e., abundance and richness of alien plants in plant communities). Our review confirms that there are more alien plant species and they are more abundant at fragment edges than in the interior of fragments. The decline on the level of invasion towards the interior of fragments is sharp. To a lesser extent, there is higher invasion in small isolated fragments than in large connected patches. However, despite their relevance, the influence of connectivity and shape of the fragments have been scarcely explored. Besides the fact that a site has more invaders if surrounded by a human-dominated landscape than by a natural one, the past history and the configuration of that landscape are also important. Invasion within land-uses is often associated with the historical legacy of changes in land-use, indicating that current land-uses might represent an invasion credit to future invasions. Accurate accounts of the invasion process and effective conservation programs will depend on such considerations.  相似文献   

15.
We examined the use of coarse resolution land cover data (USGS LUDA) to accurately discriminate ecoregions and landscape-scale features important to biodiversity monitoring and management. We used land cover composition and landscape indices, correlation and principal components analysis, and comparison with finer-grained Landsat TM data, to assess how well LUDA data discriminate changing patterns across an agriculture-forest gradient in Minnesota, U.S.A. We found LUDA data to be most accurate at general class levels of agriculture and forest dominance (Anderson Level I), but in consistent and limited in ecotonal areas of the gradient and within forested portions of the study region at finer classes (Anderson Level II). We expected LUDA to over-represent major (matrix) cover types and under-represent minor types, but this was not consistent with all classes. 1) Land cover types respond individualistically across the gradient, changing landscape grain as well as their spatial distribution and abundance. 2) Agriculture is not over-represented where it is the dominant land cover type, but forest is over-represented where it is dominant. 3) Individual forest types are under-represented in an open land matrix. 4) Within forested areas, mixed deciduous-coniferous forest is over-represented by several orders of magnitude and the separate conifer and hardwood types under-represented. Across gradual, transitional agriculture-forest areas, LUDA cover class dominance changes abruptly in a stair-step fashion. In general, rare cover types that are discrete, such as forest in agriculture or wetlands or water in forest, are more accurately represented than cover classes having lower contrast with the matrix. Northward across the gradient, important changes in the proportions of conifer and deciduous forest mixtures occur at scales not discriminated by LUDA data. Results suggest that finer-grained data are needed to map within-state ecoregions and discriminate important landscape characteristics. LUDA data, or similar coarse resolution data sources, should be used with caution and the biases fully understood before being applied in regional landscape management. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

16.
Regional land-cover change affects biodiversity, hydrology, and biogeochemical cycles at local, watershed, and landscape scales. Developing countries are experiencing rapid land cover change, but assessment is often restricted by limited financial resources, accessibility, and historical data. The assessment of regional land cover patterns is often the first step in developing conservation and management plans. This study used remotely sensed land cover and topographic data (Landsat and Shuttle Radar Topography Mission), supervised classification techniques, and spectral mixture analysis to characterize current landscape patterns and quantify land cover change from 1985 to 2003 in the Altiplano (2535–4671 m) and Intermediate Valley (Mountain) (1491–4623 m) physiographic zones in the Southeastern Bolivian Andes. Current land cover was mapped into six classes with an overall accuracy of 88% using traditional classification techniques and limited field data. The land cover change analysis showed that extensive deforestation, desertification, and agricultural expansion at a regional scale occurred in the last 20 years (17.3% of the Mountain Zone and 7.2% of the Altiplano). Spectral mixture analysis (SMA) indicated that communal rangeland degradation has also occurred, with increases in soil and non-photosynthetic vegetation fractions in most cover classes. SMA also identified local areas with intensive management activities that are changing differently from the overall region (e.g., localized areas of increased green vegetation). This indicates that actions of local communities, governments, and environmental managers can moderate the potentially severe future changes implied by the results of this study.  相似文献   

17.
The north-central region of Indiana in the Midwestern United States was covered by deciduous forest, but was largely cleared for agriculture during the 1800s. The landscape has experienced tremendous change due to forest restoration, urban expansion, and reservoir construction since the early 1900s. At the same time, ecological health and environmental quality have been dramatically degraded in the region. We used simple landscape indices, such as land proportion, TE, and Shared Edge Length (SEL) between any two classes, to examine changes in the spatial patterning of six land cover types, including agriculture, grassland, closed-canopy forest, open-canopy forest, urban, and water, using aerial photographs dating from 1940 to 1998. The landscape’s domination by agriculture did not change (65% in 1940 and 57% in 1998), but there were net gains in area for closed-canopy forest (79%), urban (256%), and water (125%). Several landscape indices did not change much but SEL between closed-canopy forest and urban increased over seven fold, and SEL between water and urban increased over eight fold from 1940 to 1998. More forestlands and water bodies were exposed to human activities. The clumped pattern of forest, water, and urban in a landscape can be ecologically detrimental and should be considered in future land-use decisions.  相似文献   

18.
In the last few years, landscape researchers have sought to understand temporal and spatial patterns of landscape changes in order to develop comprehensive models of land cover dynamics. To do so, most studies have used similar methods to quantify structural patterns, usually by comparing various landscape structural indices through time. Whereas the necessity for complementary approaches which might provide insights into landscape dynamics at some finer scale relevant to local managers has been expressed, few studies have proposed alternative methodologies. Moreover, the important relationship between the physical constraints of the landscape and land use dynamics has been seldom emphasized. Here we propose a methodological outline which was applied to the study of a rural landscape of Southern Quebec, Canada, to detect spatial and temporal (1958 to 1993) patterns of land cover changes at field, patch and landscape level. We then relate these patterns to the underlying physical structure of landscape elements using GIS and canonical correspondence analyses. We use the different geomorphological deposit types as stable discriminant factors which may constrain land use.Canonical correspondence analyses showed relations of land use and land use changes to the physical attributes of the landscape elements, whereas spatial analyses revealed very dynamic patterns at finer spatial and temporal scales. They highlighted the fact that not only the physical attributes of the landscape elements but also their spatial configuration were important determinants of land use dynamics in this area. Thus more land use changes occurred at the boundary between geomorphological deposit types than in any other locations. This trend is apparent for specific small-size changes (e.g. forest to crop), but not for the large-size ones (e.g. abandoned land to forest). Although land use changes are triggered by socioeconomic forces in this area, these changes are nevertheless constrained by the underlying physical landscape structure. A thorough comprehension of historical changes will enhance our capability to predict future landscape dynamics and devise more effective landscape management strategies.  相似文献   

19.
We used Landsat imagery and GIS to quantify the rates and patterns of landscape change between 1972 and 1992 for a 734,126 ha forested study area in the central Sikhote-alin Mountains of the Russian Far East. The study area includes a portion of the Sikhote-alinskiy Biosphere Reserve which is a part of the United Nations international Man and the Biosphere (MAB) reserve network. Wildfire is a major disturbance agent throughout the area and timber harvesting outside the reserve is also important. Maximum likelihood classification of the satellite imagery identified four broad cover types (hardwood, conifer, mixed and non-forest) in 1992 and changes among them between 1972 and 1992. We used multi-temporal principal components analysis to describe the magnitude and direction of landscape change for six watersheds that represent a range of ecological histories and disturbance regimes. Overall, forest cover declined from 90.4% in 1972 to 77.2% in 1992. The disturbance rate was more than twice as high in conifer than in hardwood forests. The rate of disturbance outside the reserve was three times that inside. While the rates of disturbance are not markedly higher than those recorded from other temperate forests, there has recently been a large alteration in the disturbance regime which will lead to a general transformation of forest composition and structure in the study area if the trend continues.  相似文献   

20.
Socioeconomic changes in many areas in the tropics have led to increasing urbanization, abandonment of agriculture, and forest re-growth. Although these patterns are well documented, few studies have examined the drivers leading to landscape-level forest recovery and the resulting spatial structure of secondary forests. Land cover transitions from agricultural lands to secondary forest in the island of Puerto Rico have been ongoing since the 1940s. This study is a glimpse into this landscape level trend from 1991 to 2000. First, we relied on Landsat images to characterize changes in the landscape structure for forest, urban, and agricultural land classes. We found that although forest cover has increased in this period, forest has become increasingly fragmented while the area of urban cover has spread faster and become more clustered. Second, we used logistic regression to assess the relationship between the transition to forest and 21 biophysical, socioeconomic, and landscape variables. We found that the percentage of forest cover within a 100 m radius of a point, distance to primary roads and nature reserves, slope, and aspect are the most important predictors of forest recovery. The resulting model predicts the spatial pattern of forest recovery with accuracy (AUC-ROC = 0.798). Together, our results suggest that forest recovery in Puerto Rico has slowed down and that increasing pressure from urbanization may be critical in determining future landscape level forest recovery. These results are relevant to other areas in the tropics that are undergoing rapid economic development.  相似文献   

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