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1.
Neutral models for the analysis of broad-scale landscape pattern 总被引：47，自引：19，他引：28
Robert H. Gardner Bruce T. Milne Monica G. Turnei Robert V. O'Neill 《Landscape Ecology》1987,1(1):19-28
The relationship between a landscape process and observed patterns can be rigorously tested only if the expected pattern in the absence of the process is known. We used methods derived from percolation theory to construct neutral landscape models,i.e., models lacking effects due to topography, contagion, disturbance history, and related ecological processes. This paper analyzes the patterns generated by these models, and compares the results with observed landscape patterns. The analysis shows that number, size, and shape of patches changes as a function of p, the fraction of the landscape occupied by the habitat type of interest, and m, the linear dimension of the map. The adaptation of percolation theory to finite scales provides a baseline for statistical comparison with landscape data. When USGS land use data (LUDA) maps are compared to random maps produced by percolation models, significant differences in the number, size distribution, and the area/perimeter (fractal dimension) indices of patches were found. These results make it possible to define the appropriate scales at which disturbance and landscape processes interact to affect landscape patterns. 相似文献
2.
Pattern in ecological landscapes is often the result of different processes operating at different scales. Neutral landscape models were introduced in landscape ecology to differentiate patterns that are the result of simple random processes from patterns that arise from more complex ecological processes. Recent studies have used increasingly complex neutral models that incorporate contagion and other constraints on random patterns, as well as using neutral landscapes as input to spatial simulation models. Here, I consider a common mathematical framework based on spectral transforms that represents all neutral landscape models in terms of sets of spectral basis functions. Fractal and multi-fractal models are considered, as well as models with multiple scaling regions and anisotropy. All of the models considered are shown to be variations on a basic theme: a scaling relation between frequency and amplitude of spectral components. Two example landscapes examined showed long-range correlations (distances up to 1000 km) consistent with fractal scaling. 相似文献
3.
Andrade Riley Franklin Janet Larson Kelli L. Swan Christopher M. Lerman Susannah B. Bateman Heather L. Warren Paige S. York Abigail 《Landscape Ecology》2021,36(1):1-15
Context
Ecological communities in urban ecosystems are assembled through ecological processes, such as species interactions, dispersal, and environmental filtering, but also through human factors that create and modify the landscape. These complex interactions make it difficult to untangle the relationships between social–ecological dynamics and urban biodiversity.
ObjectivesAs a result, there has been a call for research to address how human activities influence the processes by which ecological communities are structured in urban ecosystems. We address this research challenge using core concepts from landscape ecology to develop a framework that links social-ecological dynamics to ecological communities using the metacommunity perspective.
MethodsThe metacommunity perspective is a useful framework to explore the assembly of novel communities because it distinguishes between the effects of local environmental heterogeneity and regional spatial processes in structuring ecological communities. Both are shaped by social–ecological dynamics in urban ecosystems.
ResultsIn this paper, we define social, environmental, and spatial processes that structure metacommunities, and ultimately biodiversity, in cities. We then address how our framework could be applied in urban ecosystem research to understand multi-scalar biodiversity patterns.
ConclusionsOur framework provides a theoretical and empirical foundation for transdisciplinary research to examine how social-ecological dynamics mediate the assembly of novel communities in urban ecosystems.
相似文献4.
Tick density and population dynamics are important factors in the ecological processes involved in pathogen circulation in
a habitat. These characteristics of tick populations are closely linked to habitat suitability, which reflects the limiting
ecological factors and landscape features affecting tick populations; however, little work has been done on the regional assessment
of habitat suitability. In this study, a regional model for the distribution and abundance of the tick Ixodes ricinus in central Spain is developed. An occurrence and an abundance model were constructed; climate and vegetation variables were
found to be the main predictors of both occurrence and density in a relatively homogeneous matrix of habitat patches, whereas
topographical variables were found to have small contributions and were therefore discarded. The residuals of the abundance
model showed good correlation with the isolation of each patch. The predictive power of the abundance model was greatly enhanced
by inclusion of the traversability (a measure of the permeability of each patch to the propagules of the metapopulation) and
recruitment (an index of the relative importance of each patch to the traffic through the entire habitat network). The removal
from the landscape of the patches whose recruitment values were in the top 10% has a critical effect on tick density, an effect
not observed when patches are removed at random. These results indicate that permanent tick populations can be sustained only
in landscapes containing a minimum network of viable sites. Graph theory and measurements of patch isolation should prove
to be important elements in the forecasting of tick abundance and the management of the features underlying the landscape
ecology of tick populations and pathogen circulation in the field. 相似文献
5.
6.
Spatial and temporal analysis of landscape patterns 总被引：89，自引：0，他引：89
Monica G. Turner 《Landscape Ecology》1990,4(1):21-30
A variety of ecological questions now require the study of large regions and the understanding of spatial heterogeneity. Methods
for spatial-temporal analyses are becoming increasingly important for ecological studies. A grid cell based spatial analysis
program (SPAN) is described and results of landscape pattern analysis using SPAN are presentedd. Several ecological topics
in which geographic information systems (GIS) can play an important role (landscape pattern analysis, neutral models of pattern
and process, and extrapolation across spatial scales) are reviewed. To study the relationship between observed landscape patterns
and ecological processes, a neutral model approach is recommended. For example, the expected pattern (i.e., neutral model) of the spread of disturbance across a landscape can be generated and then tested using actual landscape data
that are stored in a GIS. Observed spatial or temporal patterns in ecological data may also be influenced by scale. Creating
a spatial data base frequently requires integrating data at different scales. Spatial is shown to influence landscape pattern
analyses, but extrapolation of data across spatial scales may be possible if the grain and extent of the data are specified.
The continued development and testing of new methods for spatial-temporal analysis will contribute to a general understanding
of landscape dynamics. 相似文献
7.
Randy T. Larsen John A. Bissonette Jerran T. Flinders Mevin B. Hooten Tammy L. Wilson 《Landscape Ecology》2010,25(1):135-145
Free water is considered important to wildlife in arid regions. In the western United States, thousands of water developments
have been built to benefit wildlife in arid landscapes. Agencies and researchers have yet to clearly demonstrate their effectiveness.
We combined a spatial analysis of summer chukar (Alectoris chukar) covey locations with dietary composition analysis in western Utah. Our specific objectives were to determine if chukars
showed a spatial pattern that suggested association with free water in four study areas and to document summer dietary moisture
content in relation to average distance from water. The observed data for the Cedar Mountains study area fell within the middle
of the random mean distance to water distribution suggesting no association with free water. The observed mean distance to
water for the other three areas was much closer than expected compared to a random spatial process, suggesting the importance
of free water to these populations. Dietary moisture content of chukar food items from the Cedar Mountains (59%) was significantly
greater (P < 0.05) than that of birds from Box Elder (44%) and Keg-Dugway (44%). Water developments on the Cedar Mountains are likely
ineffective for chukars. Spatial patterns on the other areas, however, suggest association with free water and our results
demonstrate the need for site-specific considerations. Researchers should be aware of the potential to satisfy water demand
with pre-formed and metabolic water for a variety of species in studies that address the effects of wildlife water developments.
We encourage incorporation of spatial structure in model error components in future ecological research. 相似文献
8.
Landscape services as a bridge between landscape ecology and sustainable development 总被引：7，自引：5，他引：2
Landscape ecology is in a position to become the scientific basis for sustainable landscape development. When spatial planning
policy is decentralised, local actors need to collaborate to decide on the changes that have to be made in the landscape to
better accommodate their perceptions of value. This paper addresses two prerequisites that landscape ecological science has
to meet for it to be effective in producing appropriate knowledge for such bottom-up landscape-development processes—it must
include a valuation component, and it must be suitable for use in collaborative decision-making on a local scale. We argue
that landscape ecological research needs to focus more on these issues and propose the concept of landscape services as a
unifying common ground where scientists from various disciplines are encouraged to cooperate in producing a common knowledge
base that can be integrated into multifunctional, actor-led landscape development. We elaborate this concept into a knowledge
framework, the structure–function–value chain, and expand the current pattern–process paradigm in landscape ecology with value
in this way. Subsequently, we analyse how the framework could be applied and facilitate interdisciplinary research that is
applicable in transdisciplinary landscape-development processes. 相似文献
9.
以唐山市为例，将生态安全格局与修复分区相结合，实现点线面共同指导分区。首先基于“压力—状态—潜力”框架，利用z-score标准化，在乡镇尺度上进行国土空间生态修复分区；其次构建生态安全格局，采用形态学空间格局分析与景观连通性提取生态源地，利用最小累积阻力模型识别生态廊道；最终通过生态安全格局对生态修复分区进行修正。结果表明：(1)研究区高退化压力区主要位于城市中部及各县区中心，并向四周递减；生态系统服务状态分布为北高中低，且高值区向低值区存在明显过渡；恢复潜力为由北向南先减少后增多。(2)修正后生态修复分区划分为生态保育区、生态潜在恢复区、生态优先修复区、生态修复治理区、生态修复利用区5大类型区，其中生态保育区依据生态源地与廊道所在位置划为一级保育区、二级保育区。 相似文献
10.
Management of ecosystems often focuses on specific species chosen for their habitat demand, public appeal, or levels of threat.
We propose a complementary framework for choosing focal species, the mobile link concept, which allows managers to focus on
spatial processes and deal with multi-scale ecological dynamics. Spatial processes are important for three reasons: maintenance,
re-organization, and restoration of ecological values. We illustrate the framework with a case study of the Eurasian Jay,
a mobile link species of importance for the oak forest regeneration in the Stockholm National Urban Park, Sweden, and its
surroundings. The case study concludes with a conceptual model for how the framework can be applied in management. The model
is based on a review of published data complemented with a seed predation experiment and mapping of Jay territories to reduce
the risk of applying non-urban site-specific information in an urban setting. Our case study shows that the mobile link approach
has several advantages: (1) Reducing the vulnerability of ecological functions to disturbances and fluctuations in resources
allocated to management, (2) Reducing management costs by maintaining natural processes, and (3) Maintaining gene flow and
genetic diversity at a landscape level. We argue that management that includes mobile link organisms is an important step
towards the prevention of ecosystem degradation and biodiversity loss in increasingly fragmented landscapes. Identifying and
managing mobile links is a way to align management with the ecologically relevant scales in any landscape. 相似文献
11.
The analysis of spatial patterns is fundamental to understanding ecological processes across geographic scales. Through an analysis of two simple, one-dimensional stochastic models, we develop a framework for identifying the scale of processes producing pattern. We show that for some simple model systems spectral analysis identifies exactly the scale of pattern formation. In other, more complicated systems, autocorrelation analysis appears to yield greater insight into the scale of the dynamics producing pattern; in these, the relative importance of processes at different scales can be determined directly from the change in slope of the autocorrelation function.In general, it is not possible to state which technique will be most useful in the analysis of pattern. Spectral analysis and autocorrelation analysis represent duals that can be extended and applied to more complex systems, potentially yielding insight into the nature of a wide variety of spatially determined ecological processes. 相似文献
12.
Determination of ecological scale 总被引：4，自引：0，他引：4
David W. Carlile John R. Skalski John E. Batker John M. Thomas V. I. Cullinan 《Landscape Ecology》1989,2(4):203-213
We suggest that ecological processes and physical characteristics possess an inherent scale at which the processes or characteristics occur over the landscape. We propose a conceptual spatial response model that describes the nature of this ecological scale. Based on the proposed spatial model, we suggest methods for estimating the size of study plots or transects and the distance between replicate plots needed to approach statistical independence. Using data on percent cover for Agropyron spicatum, a common arid-land bunchgrass, we demonstrated four relationships that should hold if the spatial response model is appropriate. These relationships are sample variance increases as functions of (1) transect segment length and (2) intersegment length (transect segment dispersal), and correlation decreases as functions of (3) intersegment length and (4) transect segment length. Based on evaluation of these four relationships, cover for A. spicatum is correlated over the landscape on a scale of 400 to 700 m, and a segment length of 64 to 128 m is most appropriate for measuring cover for this species. 相似文献
13.
Modelling land cover transitions: A solution to the problem of spatial dependence in data 总被引：1，自引：1，他引：1
Raster-based spatial land cover transition models (LCTMs) are widely used in landscape ecology. However, many LCTMs do not account for spatial dependence of the input data, which may artificially fragment the output spatial configuration. We demonstrate the consequences of ignoring spatial dependence, thus assigning probabilities randomly in space, using a simple LCTM. We ran the model from four different initial conditions with distinct spatial configurations and results indicated that, after 20 simulation steps, all of them converged towards the spatial configuration of the random data set. From an ecological perspective this is a serious problem because ecological data often exhibit distinct spatial configuration related to ecological processes. As a solution, we propose an approach (region approach) that accounts for spatial dependence of LCTM input data. Underlying spatial dependence was used to apply spatial bias to probability assignment within the model. As a case study we applied a region approach to a Vegetation Transition Model (VTM); a semi-Markovian model that simulates forest succession. The VTM was applied to approximately 500,000 ha of boreal forest in Ontario, at 1 ha pixel resolution. When the stochastic transition algorithms were applied without accounting for spatial dependence, spatial configuration of the output data became progressively more fragmented. When the VTM was applied using the region approach to account for spatial dependence output fragmentation was reduced. Accounting for spatial dependence in transition models will create more reliable output for analyzing spatial patterns and relating those patterns to ecological processes.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
14.
G. Darrel Jenerette 《Landscape Ecology》2018,33(10):1655-1668
Context
Ecological research, from organismal to global scales and spanning terrestrial, hydrologic, and atmospheric domains, can contribute more to reducing health vulnerabilities. At the same, ecological research directed to health vulnerabilities provides a problem-based unifying framework for urban ecologists.Objective
Provide a framework for expanding ecological research to address human health vulnerabilities in cities.Methods
I pose an urban ecology of human health framework that considers how the ecological contributions to health risks and benefits are driven by interacting influences of the environment, active management, and historical legacies in the context of ecological self-organization. The ecology of health framework is explored for contrasting examples including heat, vector borne diseases, pollution, and accessible greenspace both individually and in a multifunctional landscape perspective.Results
Urban ecological processes affect human health vulnerability through contributions to multiple hazard and well-being pathways. The resulting multifunctional landscape of health vulnerability features prominent hotspots and regional injustices. A path forward to increase knowledge of the ecological contributions to health vulnerabilities includes increased participation in in interdisciplinary teams and applications of high resolution environmental sensing and modeling.Conclusions
Research and management from a systems and landscape perspective of ecological processes is poised to help reduce urban health vulnerability and provide a better understanding of ecological dynamics in the Anthropocene.15.
A common approach to land use change analyses in multidisciplinary landscape-level studies is to delineate discrete forest
and non-forest or urban and non-urban land use categories to serve as inputs into sets of integrated sub-models describing
socioeconomic and ecological processes. Such discrete land use categories, however, may be inappropriate when the socioeconomic
and ecological processes under study are sensitive to a range of human habitation. In this paper, we characterize the spatial
dynamic distribution of humans throughout the forest landscape of western Oregon (USA). We develop an empirical model describing
the spatial distribution and rate of change in historic building densities as a function of a gravity index of development
pressure, existing building densities, slope, elevation, and existing land use zoning. We use the empirical model to project
changes in building densities that are applied to a 1995 base map of building density to describe future spatial distributions
of buildings over time. The projected building density maps serve as inputs into a multidisciplinary landscape-level analysis
of socioeconomic and ecological processes in Oregon's Coast Range Mountains.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
16.
Lieven Claessens Peter H. Verburg Jeroen M. Schoorl Anthony Veldkamp 《Landscape Ecology》2006,21(1):63-76
In this paper the use of topographical attributes for the analysis of the spatial distribution and ecological cycle of kauri
(Agathis australis), a canopy emergent conifer tree from northern New Zealand, is studied. Several primary and secondary topographical attributes
are derived from a Digital Elevation Model (DEM) for a study area in the Waitakere Ranges. The contribution of these variables
in explaining presence or absence of mature kauri is assessed with logistic regression and Receiver Operating Characteristic
(ROC) plots. A topographically based landslide hazard index, calculated by combining a steady state hydrologic model with
the infinite slope stability equation, appears to be very useful in explaining the occurrence and ecological dynamics of kauri.
It is shown that the combination of topographical, soil physical and hydrological parameters in the calculation of this single
landslide hazard index, performs better in explaining presence of mature kauri than using topographical attributes calculated
from the DEM alone. Moreover, this study demonstrates the possibilities of using terrain attributes for representing geomorphological
processes and disturbance mechanisms, often indispensable in explaining a species’ ecological cycle. The results of this analysis
support the ‘temporal stand replacement model’, involving disturbance as a dominant ecological process in forest regeneration,
as an interpretation of the community dynamics of kauri. Furthermore a threshold maturity stage, in which trees become able
to stabilize landslide prone sites and postpone a possible disturbance, together with great longevity are seen as major factors
making kauri a ‘landscape engineer’. 相似文献
17.
Globalisation accelerates the dynamics of the network society and economy, in which distant relationships become functionally
more significant than local landscape relationships. This presents challenges and opportunities for landscape analysis. Using
social scientific concepts of global and local space, and ecological concepts of hierarchy, two qualitative case studies are
undertaken of urban fringe landscapes in Copenhagen, Denmark, and Christchurch, New Zealand. They reveal a convergence of
landscape pattern over time, but this disguises significant differences in underlying socio-economic process and institutional
response. There are several implications for landscape analysis and policy. First, there is a need for studies grounded in
particular landscapes that acknowledge both local spatial landscape relationships and non spatial ‘global’ processes. Second, the transformation of landscapes through urbanisation provides a useful focus for
the connection of landscape ecological understanding of landscape systems with social scientific understanding of human agency
and social structure. Third, there is a significant challenge in how to develop local and regional institutions and policies
that have the capacity to utilise and apply these diverse analytical perspectives. 相似文献
18.
Design in science: extending the landscape ecology paradigm 总被引：9，自引：7，他引：2
Landscape ecological science has produced knowledge about the relationship between landscape pattern and landscape processes,
but it has been less effective in transferring this knowledge to society. We argue that design is a common ground for scientists
and practitioners to bring scientific knowledge into decision making about landscape change, and we therefore propose that
the pattern–process paradigm should be extended to include a third part: design. In this context, we define design as any
intentional change of landscape pattern for the purpose of sustainably providing ecosystem services while recognizably meeting
societal needs and respecting societal values. We see both the activity of design and the resulting design pattern as opportunities
for science: as a research method and as topic of research. To place design within landscape ecology science, we develop an
analytic framework based on the concept of knowledge innovation, and we apply the framework to two cases in which design has
been used as part of science. In these cases, design elicited innovation in society and in science: the design concept was
incorporated in societal action to improve landscape function, and it also initiated scientific questions about pattern–process
relations. We conclude that landscape design created collaboratively by scientists and practitioners in many disciplines improves
the impact of landscape science in society and enhances the saliency and legitimacy of landscape ecological scientific knowledge. 相似文献
19.
Quantifying scale-dependent effects of animal movement with simple percolation models 总被引：4，自引：0，他引：4
A simple model of animal movement on random and patterned landscapes was used to explore the problems of extrapolating information across a range of spatial scales. Simulation results indicate that simple relation- ships between pattern and process will produce a variety of scale-dependent effects. These theoretical studies can be used to design experiments for determining the nature of scale-dependent processes and to estimate parameters for extrapolating information across scales. 相似文献
20.
Michael C. Wimberly 《Landscape Ecology》2006,21(1):35-46
Although landscape ecology emphasizes the effects of spatial pattern on ecological processes, most neutral models of species–habitat relationships have treated habitat as a static constraint. Do the working hypotheses derived from these models extend to real landscapes where disturbances create a shifting mosaic? A spatial landscape simulator incorporating vegetation dynamics and a metapopulation model was used to compare species in static and dynamic landscapes with identical habitat amounts and spatial patterns. The main drivers of vegetation dynamics were stand-replacing disturbances, followed by gradual change from early-successional to old-growth habitats. Species dynamics were based on a simple occupancy model, with dispersal simulated as a random walk. As the proportion of available habitat (p) decreased from 1.0, species occupancy generally declined more rapidly and reached extinction at higher habitat levels in dynamic than in static landscapes. However, habitat occupancy was sometimes actually higher in dynamic landscapes than in static landscapes with similar habitat amounts and patterns. This effect was most pronounced at intermediate amounts of habitat (p = 0.3?0.6) for mobile species that had high colonization rates, but were unable to cross non-habitat patches. Differences between static and dynamic landscapes were contingent upon the initial metapopulation size and the shapes of disturbances and the resulting habitat patterns. Overall, the results demonstrate that dispersal-limited species exhibit more pronounced critical behavior in dynamic landscapes than is predicted by simple neutral models based on static landscapes. Thus, caution should be exercised in extending generalizations derived from static landscape models to disturbance-driven landscape mosaics. 相似文献