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1.
Radioactive contamination of agricultural land may necessitate long-term changes in food production systems, through application
of selected countermeasures, in order to reduce the accumulation of radionuclides in food. We quantified the impact of selected
countermeasures on habitat diversity, using the hypothetical case of two agricultural areas in Finland. The management scenarios
studied were conversions from grassland to cereal production and from grassland and crop production to afforestation. The
two study sites differed with respect to present agricultural production: one being predominantly cereal production and seminatural
grasslands, while the other was dominated by intensive grass and dairy production. Some of the management scenarios are expected
to affect landscape structures and habitat diversity. These potential changes were assessed using a spatial pattern analysis
program in connection with geographic information systems. The studied landscape changes resulted in a more monotonous landscape
structure compared to the present management, by increasing the mean habitat patch size, reducing the total habitat edge length
and reducing the overall habitat diversity calculated by the Shannon diversity index. The degree of change was dependent on
the present agricultural management practice in the case study sites. Where dairy production was predominant, the landscape
structure changes were mostly due to conversion of intensive pastures and grasslands to cereal production. In the area dominated
by cereal production and seminatural grasslands, the greatest predicted impacts resulted from afforestation of meadows and
pastures. The studied management changes are predicted to reduce biodiversity at the species level as well as diminishing
species-rich habitats. This study has predicted prominent side effects in habitat diversity resulting from application of
management scenarios. These potential long-term impacts should be considered by decision-makers when planning future strategies
in the event of radionuclide deposition. 相似文献
2.
The Fate of Priority Areas for Conservation in Protected Areas: A Fine-Scale Markov Chain Approach 总被引:1,自引:0,他引:1
Park managers in alpine areas must deal with the increase in forest coverage that has been observed in most European mountain
areas, where traditional farming and agricultural practices have been abandoned. The aim of this study is to develop a fine-scale
model of a broad area to support the managers of Paneveggio Nature Park (Italy) in conservation planning by focusing on the
fate of priority areas for conservation in the next 50–100 years. GIS analyses were performed to assess the afforestation
dynamic over time using two historical maps (from 1859 and 1936) and a series of aerial photographs and ortho-photos (taken
from 1954 to 2006) covering a time span of 150 years. The results show an increase in the forest surface area of about 35%.
Additionally, the forest became progressively more compact and less fragmented, with a consequent loss of ecotones and open
habitats that are important for biodiversity. Markov chain-cellular automata models were used to project future changes, evaluating
the effects on a habitat scale. Simulations show that some habitats defined as priority by the EU Habitat Directive will be
compromised by the forest expansion by 2050 and suffer a consistent loss by 2100. This protocol, applied to other areas, can
be used for designing long-term management measures with a focus on habitats where conservation status is at risk. 相似文献
3.
Landscape ecological assessment: a tool for integrating biodiversity issues in strategic environmental assessment and planning 总被引:11,自引:0,他引:11
To achieve a sustainable development, impacts on biodiversity of urbanisation, new infrastructure projects and other land use changes must be considered on landscape and regional scales. This requires that important decisions are made after a systematic evaluation of environmental impacts. Landscape ecology can provide a conceptual framework for the assessment of consequences of long-term development processes like urbanisation on biodiversity components, and for evaluating and visualising the impacts of alternative planning scenarios. The aim of this paper was to develop methods for integrating biodiversity issues in planning and strategic environmental assessment in an urbanising environment, on landscape and regional levels. In order to test developed methods, a case study was conducted in the region of Stockholm, the capital of Sweden, and the study area embraced the city centre, suburbs and peri-urban areas. Focal species were tested as indicators of habitat quality, quantity and connectivity in the landscape. Predictive modelling of habitat distribution in geographic information systems involved the modelling of focal species occurrences based on empirical data, incorporated in a landscape ecological decision support system. When habitat models were retrieved, they were applied on future planning scenarios in order to predict and assess the impacts on focal species. The scenario involving a diffuse exploitation pattern had the greatest negative impacts on the habitat networks of focal species. The scenarios with concentrated exploitation also had negative impacts, although they were possible to mitigate quite easily. The predictions of the impacts on habitats networks of focal species made it possible to quantify, integrate and visualise the effects of urbanisation scenarios on aspects of biodiversity on a landscape level. 相似文献
4.
Serena De Simone Francesco Boscutti 《Journal of Environmental Planning and Management》2017,60(7):1173-1192
Design of landscape is the process of the arrangement of spatial features with the objective of sustaining ecosystem services, and maintaining ecological functionality to meet societal needs. Along a gradient of cultivation intensity, the functional quality of agricultural landscape was explored and the relationships between landscape metrics and functional quality were analyzed, in order to make effective recommendations for landscape design aimed at sustainable land use schemes. The functional quality of landscape was calculated using the InVest model for 20 farm landscapes (North-Eastern Italy) where biodiversity (plant taxa) and sensitivity to disturbance (hemeroby) were used as model inputs. Results highlighted the importance of specific habitat types such as meadows and woodlands rather than other habitats for improving the biodiversity of agricultural landscapes. A high proportion of these habitats enhanced the functional quality of the landscape when the habitats were organized in large and not isolated patches in heterogeneous landscapes. 相似文献
5.
Protected areas (PAs) are cornerstones of biodiversity conservation, but small parks alone cannot support wide-ranging species,
such as the tiger. Hence, forest dynamics in the surrounding landscapes of PAs are also important to tiger conservation. Tiger
landscapes often support considerable human population in proximity of the PA, sometimes within the core itself, and thus
are subject to various land use activities (such as agricultural expansion and road development) driving habitat loss and
fragmentation. We synthesize information from 27 journal articles in 24 tiger landscapes to assess forest-cover dynamics in
tiger-range countries. Although 29% of the PAs considered in this study have negligible change in overall forest cover, approximately
71% are undergoing deforestation and fragmentation. Approximately 58% of the total case studies have human settlements within
the core area. Most changes—including agricultural expansion, plantation, and farming (52%), fuelwood and fodder collection
(43%), logging (38%), grazing (38%), and tourism and development (10%)—can be attributed to human impacts largely linked to
the nature of the management regime. This study highlights the need for incorporating new perspectives, ideas, and lessons
learned locally and across borders into management plans to ensure tiger conservation in landscapes dominated by human activities.
Given the increasing isolation of most parks due to agricultural, infrastructural, and commercial developments at the periphery,
it is imperative to conduct planning and evaluation at the landscape level, as well as incorporate multiple actors and institutions
in planning, instead of focusing solely on conservation within the PAs as is currently the case in most tiger parks. 相似文献
6.
Alberto L. Teixido Luis G. Quintanilla Francisco Carreño David Gutiérrez 《Journal of environmental management》2010,91(4):879-886
Changes in forested landscapes may have important consequences for ecosystem services and biodiversity conservation. In northern Spain, major changes in land use occurred during the second half of the 20th century, but their impacts on forests have not been quantified. We evaluated the dynamics of landscape and forest distribution patterns between 1957 and 2003 in Fragas do Eume Natural Park (northwestern Spain). We used orthoimages and a set of standard landscape metrics to determine transitions between land cover classes and to examine forest distribution patterns. Eucalypt plantations showed the greatest increase in area (197%) over time. Furthermore, transitions to eucalypt plantations were found in all major land cover classes. Forest showed a net decline of 20% in total area and represented 30% of the landscape area in 2003. Forest losses were mainly due to eucalypt plantations and the building of a water reservoir, while forest gains were due to increases in shrubland, meadows and cultivated fields which had been recolonised. Forest patch size and core area decreased, and edge length increased over time. In turn, increases were obtained in mean distance between forest patches, and in adjacency to eucalypt plantations and to a water reservoir. These results suggest an increase in forest fragmentation from 1957 to 2003, as well as a change in the nature of the habitat surrounding forest patches. This study shows that land use changes, mostly from eucalypt plantation intensification, negatively affected forested habitats, although some regeneration was ongoing through ecological succession from land abandonment. 相似文献
7.
Industrialized agriculture currently substitutes many of the ecological functions of soil micro-organisms, macroinvertebrates, wild plants, and vertebrate animals with high cost inputs of pesticides and fertilizers. Enhanced biological diversity potentially offers agricultural producers a means of reducing the cost of their production. Conservation of biodiversity in agricultural landscapes may be greatly enhanced by the adoption of certain crop management practices, such as reduced pesticide usage or measures to prevent soil erosion. Still, the vast monocultures comprising the crop area in many Canadian agricultural landscapes are often of limited conservation value, thus the inclusion of appropriate wildlife habitat in and around arable lands is a fundamental prerequisite for the integration of wild species within agricultural landscapes. This review of current literature considers the potential for non-crop areas within agricultural landscapes to be reservoirs of agronomically beneficial organisms including plants, invertebrates, and vertebrate species. Non-crop habitats adjacent to crop land have been identified as significant for the maintenance of plant species diversity, for the conservation of beneficial pollinating and predatory insects, and as essential habitat for birds. A key component for enhancement of biodiversity is the reintroduction of landscape heterogeneity by (1) protection and enhancement of key non-crop areas, (2) smaller fields and farms, and (3) a greater mixture of crops, through rotation, intercropping and regional diversification. The benefits of increased biodiversity within arable lands are reviewed for various species groups. In the Canadian context, any serious attempt to derive significant agronomic benefit from increased biodiversity will require considerable changes in the agricultural programs and policies which shape mainstream industrialized agriculture. The problems of crop depredation by vertebrate species, weed and insect competition, which still represent significant impediments to the creation and proper management of wildlife habitat, are also discussed. 相似文献
8.
Maintaining the Conservation Value of Shifting Cultivation Landscapes Requires Spatially Explicit Interventions 总被引:1,自引:0,他引:1
Fallow vegetation within landscapes dominated by shifting cultivation represents a woody species pool of critical importance
with considerable potential for biodiversity conservation. Here, through the analysis of factors that influence the early
stages of fallow vegetation regrowth in two contrasting forest margin landscapes in Southern Cameroon, we assessed the impact
of current trends of land use intensification and expansion of the cultivated areas, upon the conservation potential of shifting
cultivation landscapes. We combined the analysis of plot and landscape scale factors and identified a complex set of variables
that influence fallow regrowth processes in particular the characteristics of the agricultural matrix and the distance from
forest. Overall we observed a decline in the fallow species pool, with composition becoming increasingly dominated by species
adapted to recurrent disturbance. It is clear that without intervention and if present intensification trends continue, the
potential of fallow vegetation to contribute to biodiversity conservation declines because of a reduced capacity, (1) to recover
forest vegetation with anything like its original species composition, (2) to connect less disturbed forest patches for forest
dependent organisms. Strategies to combat biodiversity loss, including promotion of agroforestry practices and the increase
of old secondary forest cover, will need not only to operate at a landscape scale but also to be spatially explicit, reflecting
the spatial pattern of species reservoirs and dispersal strategies and human usage across landscapes. 相似文献
9.
Marianne Lindström Maria Johansson Jan Herrmann Olle Johnsson 《Journal of Environmental Planning and Management》2006,49(4):495-513
Human actions towards land, freshwater and oceans have already caused biodiversity to decline. This study aims to investigate attitudes towards the conservation of biological biodiversity among different groups in a Swedish city, Kristianstad. An inquiry including statements measuring attitudes towards the conservation of habitats, animals and plants, to the biological diversity within selected local areas, to global and national areas, and to societal issues, was replied to by 271 persons. Deciduous forests, birds and wild flowers were given highest priority. An area categorized as wetland including lakeshore meadows with a rich bird life was prioritized as most important for conservation while a forest area was chosen as best for recreation. The experts gave lower priority to arable land, urban parks, domestic animals, agricultural and garden plants and to conifer forests compared to the other groups. Knowledge about what people in general value as important could facilitate the future planning of nature areas in the city of Kristianstad. 相似文献
10.
Corace RG Shartell LM Schulte LA Brininger WL McDowell MK Kashian DM 《Environmental management》2012,49(2):359-371
To facilitate forest planning and management on National Wildlife Refuges, we synthesized multiple data sources to describe
land ownership patterns, land cover, landscape pattern, and changes in forest composition for four ecoregions and their associated
refuges of the Upper Midwest. We related observed patterns to ecological processes important for forest conservation and restoration,
with specific attention to refuge patterns of importance for forest landbirds of conservation priority. The large amount of
public land within the ecoregions (31–80%) suggests that opportunities exist for coarse and meso-scale approaches to conserving
and restoring ecological processes affecting the refuges, particularly historical fire regimes. Forests dominate both ecoregions
and refuges, but refuge forest patches are generally larger and more aggregated than in associated ecoregions. Broadleaf taxa
have increased in dominance in the ecoregions and displaced fire-dependent taxa such as pine (Pinus spp.) and other coniferous species; these changes in forest composition have likely also affected refuge forests. Despite
compositional changes, larger forest patches on refuges suggests that they may provide better habitat for area-sensitive forest
landbirds of mature, compositionally diverse forests than surrounding lands if management continues to promote increased patch
size. We reason that although fine-scale research and monitoring for species of conservation priority is important, broad
scale (ecoregional) assessments provide crucial context for effective forest and wildlife management in protected areas. 相似文献
11.
It is usually inappropriate to define rectangular land areas or administrative units as the extent for quantifying landscapes
that possess hierarchical structure. As a functional unit established by geophysical relationships, the watershed is one of
many natural scales in the hierarchical landscape. We examined the dynamics of the Yashiro watershed of Japan at the landscape
level using pattern metrics based on Landsat thematic mapper (TM) imagery from 1985 to 1998. This watershed provides important
habitats for the hooded crane (Grus monachus), a vulnerable species. While its world population has remained stable, the number wintering at Yashiro has declined in recent
years. Changes in landscape metrics reveal that the spatial pattern within the watershed underwent homogenization due to depopulation
of local people and shifts in local energy requirements and forest management policy at Yashiro. Specific changes include:
a decrease in bare land area from 6.2% to 1.0% of the landscape, increased forest cover from 69.2% to 76.1%, reduction in
patch number from 1194 to 616 and enlarged mean patch size, and a decrease in total edge from 223,740 m to 158,040 m. The
rate of change in landscape metrics indicates a rapid change towards homogeneity in the landscape since 1990. The temporal
changes in hooded crane populations corresponded to the changes in landscape. An alternative explanation has been proposed
that decline of the species is influenced by landscape dynamics affecting both habitat selection and food resources. Conservation
at the watershed scale is suggested to be complementary to the current conservation measures of the species. 相似文献
12.
Edith González Afanador Michael E. Kjelland X. Ben Wu Neal Wilkins William E. Grant 《The Environmentalist》2016,36(3):310-328
The present research focused on using spatial analysis to determine relationships among land ownership property sizes and landscape structure, with a focus on conservation management implications. Indices and metrics of ownership property sizes and landscape structure were calculated for 20 km buffer areas around 31 North American Breeding Bird Survey transects, 12 located within the Edwards Plateau ecoregion and 18 in contiguous ecoregions. The number of bird species observed at each transect provided a measure of avian species richness associated with land cover classes for each respective transect (González in Urban influence on diversity of avifauna in the Edwards Plateau of Texas: effect of property sizes on rural landscape structure, Texas A&M University, 2005). Spatial correlations were calculated between each pair of the landscape indices. Spatial analysis identified a “threshold of habitat fragmentation” for the 500 acre (ac) ownership property size. Significant spatial correlations among variables showed that property sizes lower than 500 ac produced habitat fragmentation represented by a decrease in mean patch size (MN) and proximity among habitat patches (Index PROX). Spatial analysis also made possible the prioritization of ecological sub-regions of the Edwards Plateau for conservation or restoration. The Live Oak-Mesquite Savannah showed the highest average ownership property size (7305 ac) and the highest values of patch richness. Based on the results, management in the Live Oak-Mesquite Savannah sub-region should focus on the conservation of land mosaic diversity to assure native avian species turnover (Whittaker 1972). In Balcones Canyon Lands, 64 % of land was covered by farms smaller than 500 ac and the overall average ownership property size was above the threshold of fragmentation (1440 ac), implying that management policies there should focus both on habitat conservation and on restoration. In contrast, 71 % of land in the Lampasas Cut Plains was covered by farms smaller than 500 ac, and average ownership property size was very close to the fragmentation threshold (625 ac). Consequently, the results indicate that management in the Lampasas Cut Plains sub-region should focus on habitat restoration (e.g., corridors that connect isolated habitat patches). In general, the threshold of ownership property size, 500 ac, is important for conservation planning because below that threshold of property size, habitat patch size begins to decrease and the distance between equivalent patches of habitat increases. Isolated patches act as islands within a sea of less suitable habitat which produce negative effects on biodiversity. Identifying the spatial characteristics indicative of habitat fragmentation, or the likelihood thereof, is an important issue for conservation planning in places with urban sprawl influence. 相似文献
13.
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15.
Land uses such as forestry and agriculture are presumed to degrade the biodiversity of riparian wetlands in the northern temperate regions of the United States. In order to improve land use decision making in this landscape, floral and faunal communities of 15 riparian wetlands associated with low-order streams were related to their surrounding land cover to establish which organismal groups are affected by anthropogenic disturbance and whether these impacts are scale-specific. Study sites were chosen to represent a gradient of disturbance. Vascular plants of wet meadow and shrub carr communities, aquatic macro-invertebrates, amphibians, fish and birds were surveyed, and total abundance, species richness and Shannon diversity were calculated. For each site, anthropogenic disturbances were evaluated at local and landscape scales (500, 1000, 2500 and 5000 m from the site and the site catchment) from field surveys and a geographic information system (GIS). Land use data were grouped into six general land use types: urban, cultivated, rangeland, forest, wetland and water. Shrub carr vegetation, bird and fish diversity and richness generally decrease with increasing cultivation in the landscape. Amphibian abundance decreases and fish abundance increases as the proportions of open water and rangeland increases; bird diversity and richness increase with forest and wetland extent in the landscape. Wet meadow vegetation, aquatic macro-invertebrates, amphibians and fish respond to local disturbances or environmental conditions. Shrub carr vegetation, amphibians and birds are influenced by land use at relatively small landscape scales (500 and 1000 m), and fish respond to land use at larger landscape scales (2500, 5000 m and the catchment). Effective conservation planning for these riparian wetlands requires assessment of multiple organismal groups, different types of disturbance and several spatial scales.1998 Academic Press 相似文献
16.
Fragmentation of natural habitats is one of the main causes of the loss of biodiversity. However, all plants do not respond to habitat fragmentation in the same way due to differences in species traits. We studied the effect of patch size and isolation on the biodiversity of vegetation in the mixed-oak forests in the north of the Iberian Peninsula. The aim was to evaluate whether all the growth-forms of vegetation are equally affected by forest fragmentation in order to improve the management strategies to restore this type of vegetation. This study has shown that the effect of the area and spatial isolation of the patches was not the same for the different growth-forms. Fragmentation had a mainly negative effect on the richness and diversity of forest specialist species, especially ferns and herbaceous growth-forms. Moreover, the presence and/or cover of woodland herbaceous species (such as Lamiastrum galeobdolon and Helleborus viridis) and of woodland ferns (namely Asplenium adiantum-nigrum, Asplenium trichomanes, Polystichum setiferum, Dryopteris affinis) were negatively affected by patch size, possibly due to the reduction of habitat quality. These species have been replaced by more generalist species (such as Cardamine pratensis, Cirsium sp., Pulmonaria longifolia or Rumex acetosella) in small patches. Patch isolation had a negative effect on the presence of forest specialist species (namely, L.?galeobdolon, Frangula alnus, Hypericum androsaemum, A.?adiantum-nigrum and Athyrium filix-femina) and favored colonization by more generalist species such as Cirsium sp., Calluna vulgaris, Erica arborea or Ulex sp. Thus, in this region special attention should be paid to the conservation of forest specialist species, especially ferns and herbs. In conservation policy focused on forest specialist species, the most valuable species in forest ecosystems, conservation of large forest areas should be promoted. 相似文献
17.
Jin Longru Hong S. He Zhou Yufei Bu Rencang Sun Keping 《Environmental management》2010,45(5):1191-1200
Forest management often has cumulative, long-lasting effects on wildlife habitat suitability and the effects may be impractical
to evaluate using landscape-scale field experiments. To understand such effects, we linked a spatially explicit landscape
disturbance and succession model (LANDIS) with habitat suitability index (HSI) models to assess the effects of management
alternatives on habitat suitability in a forested landscape of northeastern China. LANDIS was applied to simulate future forest
landscape changes under four management alternatives (no cutting, clearcutting, selective cutting I and II) over a 200-year
horizon. The simulation outputs were linked with HSI models for three wildlife species, the red squirrel (Sciurus vulgaris), the red deer (Cervus elaphus) and the hazel grouse (Bonasa bonasia). These species are chosen because they represent numerous species that have distinct habitat requirements in our study area.
We assessed their habitat suitability based on the mean HSI values, which is a measure of the average habitat quality. Our
simulation results showed that no one management scenario was the best for all species and various forest management scenarios
would lead to conflicting wildlife habitat outcomes. How to choose a scenario is dependent on the trade-off of economical,
ecological and social goals. Our modeling effort could provide decision makers with relative comparisons among management
scenarios from the perspective of biodiversity conservation. The general simulation results were expected based on our knowledge
of forest management and habitat relationships of the species, which confirmed that the coupled modeling approach correctly
simulated the assumed relationships between the wildlife, forest composition, age structure, and spatial configuration of
habitat. However, several emergent results revealed the unexpected outcomes that a management scenario may lead to. 相似文献
18.
Conserving biodiversity that matters: practitioners' perspectives on brownfield development and urban nature conservation in London 总被引:4,自引:0,他引:4
Policies designed to conserve sites of nature conservation importance are an important aspect of city planning in the UK. London has led the way in putting in place a spatial hierarchy of sites of nature conservation importance designed to protect wildlife habitats from development. Some wasteland habitats associated with derelict and vacant land receive protection in this way but development pressure on these so-called 'brownfield sites' is high and is likely to continue. This paper examines how conservation professionals in the private, public and voluntary sectors are responding to the threats of biodiversity loss and opportunities for habitat creation posed by re-development of brownfield sites. The study draws on in-depth interviews conducted with conservation professionals and the practices employed by ecological advisers employed by developers seeking to re-develop wasteland sites. It finds that practitioners are negotiating their role in the re-development process in different ways. Key issues relate to the role of ecological science in codifying wasteland habitats, uncertainties about how best to evaluate the conservation importance of such sites and the strategies and tactics employed by different practitioners as they seek to mobilise a range of knowledges and practices to secure ecologically sensitive proposals. Scientific knowledge about wasteland habitats has not stabilised in ways that can consistently inform conservation policy and practice. As a result biodiversity issues of wasteland sites are often discounted in the re-development process. Investment in studies of the basic ecology of urban wastelands could provide a firmer scientific foundation on which conservation policies could build. At the same time, many conservation professionals involved in urban re-development are struggling to promote a pro-active approach to secure environmentally sensitive development. The knowledge and co-operation networks being mobilised to support this approach are fluid and unstable, and favourable development outcomes as yet are few. Formalising these networks to achieve more effective engagements with developers and the construction industry could consolidate ecological practices designed to conserve and re-create the biodiversity of wasteland habitats. 相似文献
19.
Qiu Z 《Environmental management》2003,32(3):299-311
Conservation buffers have the potential to reduce agricultural nonpoint source pollution and improve terrestrial wildlife habitat, landscape biodiversity, flood control, recreation, and aesthetics. Conservation buffers, streamside areas and riparian wetlands are being used or have been proposed to control agricultural nonpoint source pollution. This paper proposes an innovative strategy for placing conservation buffers based on the variable source area (VSA) hydrology. VSAs are small, variable but predictable portion of a watershed that regularly contributes to runoff generation. The VSA-based strategy involves the following three steps: first, identifying VSAs in landscapes based on natural characteristics such as hydrology, land use/cover, topography and soils; second, targeting areas within VSAs for conservation buffers; third, refining the size and location of conservation buffers based on other factors such as weather, environmental objectives, available funding and other best management practices. Building conservation buffers in VSAs allows agricultural runoff to more uniformly enter buffers and stay there longer, which increases the buffers capacity to remove sediments and nutrients. A field-scale example is presented to demonstrate the effectiveness and cost-effectiveness of the within-VSA conservation buffer scenario relative to a typical edge-of-field buffer scenario. The results enhance the understanding of hydrological processes and interactions between agricultural lands and conservation buffers in agricultural landscapes, and provide practical guidance for land resource managers and conservationists who use conservation buffers to improve water quality and amenity values of agricultural landscape. 相似文献
20.
Assessing Land-Use Impacts on Natural Resources 总被引:3,自引:1,他引:2
V. H. Dale A. W. King L. K. Mann R. A. Washington-Allen R. A. McCord 《Environmental management》1998,22(2):203-211
/ Much information is available on changes that occur in natural resources from both spatially-explicit data on environmental conditions and models of the interactions of these conditions and resources with human activities. The strategy for assessing land-use impacts on natural resources developed in this paper provides a framework for using relevant data and models to address questions of how management practices can promote both use and protection of resources. This assessment strategy integrates spatially explicit environmental data using geographic information systems (GIS) with computer models that simulate changes in land cover in response to land-use impacts. The computer models also simulate susceptibility of species to changes in habitat suitability and landscape patterns. The approach is applied to management of limestone barrens on the Oak Ridge Reservation in East Tennessee. Potential limestone barrens habitats are identified by overlaying appropriate soils, geology, slope, and land-use/land-cover conditions. Their validity is tested against known sites containing rare species that occur in these habitats. The location of habitats at risk in the aftermath of human activities is determined by using an available area model that identifies the size and proximity of sites that particular types of species can no longer use as habitat. The resulting risk map can be used in land management planning. The approach uses readily available in situ and remotely sensed data and is applicable to a wide range of locations and land-use scenarios. This approach can be refined based on needs identified by land managers and on the sensitivity of the results to the resolution of available resource information.KEY WORDS: Land management; Assessment; Habitat characterization; Limestone barrens; Ecological modeling; Geographic information systems 相似文献