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1.
Regionalization, or the grouping of objects in space, is a useful tool for organizing, visualizing, and synthesizing the information contained in multivariate spatial data. Landscape pattern indices can be used to quantify the spatial pattern (composition and configuration) of land cover features. Observable patterns can be linked to underlying processes affecting the generation of landscape patterns (e.g., forest harvesting). The objective of this research is to develop an approach for investigating the spatial distribution of forest pattern across a study area where forest harvesting, other anthropogenic activities, and topography, are all influencing forest pattern. We generate spatial pattern regions (SPR) that describe forest pattern with a regionalization approach. Analysis is performed using a 2006 land cover dataset covering the Prince George and Quesnel Forest Districts, 5.5 million ha of primarily forested land base situated within the interior plateau of British Columbia, Canada. Multivariate cluster analysis (with the CLARA algorithm) is used to group landscape objects containing forest pattern information into SPR. Of the six generated SPR, the second cluster (SPR2) is the most prevalent covering 22% of the study area. On average, landscapes in SPR2 are comprised of 55.5% forest cover, and contain the highest number of patches, and forest/non-forest joins, indicating highly fragmented landscapes. Regionalization of landscape pattern metrics provides a useful approach for examining the spatial distribution of forest pattern. Where forest patterns are associated with positive or negative environmental conditions, SPR can be used to identify similar regions for conservation or management activities. 相似文献
2.
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
3.
Landscape spatial patterns have increasingly been considered to be essential for environmental planning and resources management.
In this study, we proposed a hierarchical approach for landscape classification and evaluation by characterizing landscape
spatial patterns across different hierarchical levels. The case study site is the Red Hills region of northern Florida and
southwestern Georgia, well known for its biodiversity, historic resources, and scenic beauty. We used one Landsat Enhanced
Thematic Mapper image to extract land-use/-cover information. Then, we employed principal-component analysis to help identify
key class-level landscape metrics for forests at different hierarchical levels, namely, open pine, upland pine, and forest
as a whole. We found that the key class-level landscape metrics varied across different hierarchical levels. Compared with
forest as a whole, open pine forest is much more fragmented. The landscape metric, such as CONTIG_MN, which measures whether
pine patches are contiguous or not, is more important to characterize the spatial pattern of pine forest than to forest as
a whole. This suggests that different metric sets should be used to characterize landscape patterns at different hierarchical
levels. We further used these key metrics, along with the total class area, to classify and evaluate subwatersheds through
cluster analysis. This study demonstrates a promising approach that can be used to integrate spatial patterns and processes
for hierarchical forest landscape planning and management. 相似文献
4.
An approach based on spatial multicriteria analysis to map the nature conservation value of agricultural land 总被引:2,自引:0,他引:2
Geneletti D 《Journal of environmental management》2007,83(2):228-235
Knowledge of the nature conservation value of agricultural land provides a useful input to land-use planning. However, the scarcity of suitable data causes this component to rarely play a role. The paper proposes a methodology based on commonly available data to assess the nature conservation value of agricultural landscapes, and to generate cartographic results to be used as decision variables in planning. The approach relies on landscape ecological indicators and on the application of multicriteria analysis in a Geographical Information System (GIS) context. Four criteria were selected: the agricultural landscape type, the cover of vegetation remnants and marginal features, the length of forest-agriculture ecotones, and the proximity to nature reserves. These criteria were assessed directly or by means of specific indicators, generating maps that were subsequently aggregated through spatial multicriteria analysis. The approach was tested in an alpine area located in Trentino (northern Italy). 相似文献
5.
Assessing Impacts of Typhoons and the Chi-Chi Earthquake on Chenyulan Watershed Landscape Pattern in Central Taiwan Using Landscape Metrics 总被引:3,自引:1,他引:2
The Chi-Chi earthquake (ML = 7.3) occurred in the central part of Taiwan on September 21, 1999. After the earthquake, typhoons Xangsane and Toraji produced
heavy rainfall that fell across the eastern and central parts of Taiwan on November 2000 and July 2001. This study uses remote
sensing data, landscape metrics, multivariate statistical analysis, and spatial autocorrelation to assess how earthquake and
typhoons affect landscape patterns. It addresses variations of the Chenyulan watershed in Nantou County, near the earthquake’s
epicenter and crossed by Typhoon Toraji. The subsequent disturbances have gradually changed landscape of the Chenyulan watershed.
Disturbances of various types, sizes, and intensities, following various tracks, have various effects on the landscape patterns
and variations of the Chenyulan watershed. The landscape metrics that are obtained by multivariate statistical analyses showed
that the disturbances produced variously fragmented patches, interspersed with other patches and isolated from patches of
the same type across the entire Chenyulan watershed. The disturbances also affected the isolation, size, and shape-complexity
of patches at the landscape and class levels. The disturbances at the class level more strongly affected spatial variations
in the landscape as well as patterns of grasslands and bare land, than variations in the watershed farmland and forest. Moreover,
the earthquake with high magnitude was a starter to create these landscape variations in space in the Chenyulan watershed.
The cumulative impacts of the disturbances on the watershed landscape pattern had existed, especially landslides and grassland
in the study area, but were not always evident in space and time in landscape and other class levels. 相似文献
6.
The conversion of landscapes by human activities results in widespread changes in landscape spatial structure. Regardless of the type of land conversion, there appears to be a limited number of common spatial configurations that result from such land transformation processes. Some of these configurations are considered optimal or more desirable than others. Based on pattern geometry, we define ten processes responsible for pattern change: aggregation, attrition, creation, deformation, dissection, enlargement, fragmentation, perforation, shift, and shrinkage. A novelty in this contribution is the inclusion of transformation processes causing expansion of the land cover of interest. Consequently, we propose a decision tree algorithm that enables detection of these processes, based on three parameters that have to be determined before and after the transformation of the landscape: area, perimeter length, and number of patches of the focal landscape class. As an example, the decision tree algorithm is applied to determine the transformation processes of three divergent land cover change scenarios: deciduous woodland degradation in Cadiz Township (Wisconsin, USA) 1831–1950, canopy gap formation in a terra firme rain forest at the Tiputini Biodiversity Station (Amazonian Ecuador) 1997–1998, and forest regrowth in Petersham Township (Massachusetts, USA) 1830–1985. The examples signal the importance of the temporal resolution of the data, since long-term pattern conversions can be subdivided in stadia in which particular pattern components are altered by specific transformation processes. 相似文献
7.
Assessing the spatial distribution of grassland age in a marginal European landscape 总被引:1,自引:0,他引:1
Grassland age is increasingly recognised to be an indicator for present-day biodiversity, e.g. plant species richness, and is also important for other landscape functions. We developed a methodological approach to systematically assess the spatial distribution of grassland age in marginal European landscapes. This approach - applied to the Lahn-Dill Highlands (1270 km(2)), a marginal landscape in Hesse, Germany - comprises three steps: (1) in a two-stage stratification process, we pre-stratified the study area according to recent land-cover patterns and their changes between 1955 and 1995 (stratification I) and classified grassland types by combining data on soil moisture, base-richness, and elevation (stratification II). From 50 grassland types, we randomly selected 1000 representative grassland patches. (2) We determined the age of these patches by means of aerial photograph interpretation of a chronosequence dating back to 1953 and classified each patch with respect to the age classes young (<18 years), mid-aged (18-47 years), and old (>47 years). (3) Based on this information, we calculated grassland type-specific probabilities for grassland patches to belong to the respective age classes. These probabilities were projected to districts by direct extrapolation. An exemplary validation of extrapolation results for two test areas was performed. The results revealed that 49% of the investigated patches were old grassland. The remaining patches were mid-aged (36%) or young grassland (15%). The extrapolation results indicated accordingly a predominance of old grassland at the district scale. Occurrences of mid-aged grassland were concentrated in districts with a pronounced land-cover change, whereas young grassland is apparently evenly distributed across the study area. Validation results suggest that our approach is suitable for a realistic estimation of grassland age in marginal European landscapes. The method may be applied in landscape models of various disciplines that rely on large-scale information on grassland age. 相似文献
8.
Impacts of human land use pose an increasing threat to global biodiversity. Resource managers must respond rapidly to this threat by assessing existing natural areas and prioritizing conservation actions across multiple spatial scales. Plant species richness is a useful measure of biodiversity but typically can only be evaluated on small portions of a given landscape. Modeling relationships between spatial heterogeneity and species richness may allow conservation planners to make predictions of species richness patterns within unsampled areas. We utilized a combination of field data, remotely sensed data, and landscape pattern metrics to develop models of native and exotic plant species richness at two spatial extents (60- and 120-m windows) and at four ecological levels for northwestern Ohio’s Oak Openings region. Multiple regression models explained 37–77 % of the variation in plant species richness. These models consistently explained more variation in exotic richness than in native richness. Exotic richness was better explained at the 120-m extent while native richness was better explained at the 60-m extent. Land cover composition of the surrounding landscape was an important component of all models. We found that percentage of human-modified land cover (negatively correlated with native richness and positively correlated with exotic richness) was a particularly useful predictor of plant species richness and that human-caused disturbances exert a strong influence on species richness patterns within a mixed-disturbance oak savanna landscape. Our results emphasize the importance of using a multi-scale approach to examine the complex relationships between spatial heterogeneity and plant species richness. 相似文献
9.
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
10.
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
11.
Calvo-Iglesias MS Fra-Paleo U Crecente-Maseda R Díaz-Varela RA 《Environmental management》2006,38(6):921-933
The aim of this work is the analysis of the dynamics in cultural landscapes, focused on the spatial distribution of changes
in land cover and landscape patterns, and their possible linkages. These dynamics have been analyzed for the years 1957 and
2000 in a sector of the north of Galicia (NW Spain) characterized with diverse landscapes. Afforestation processes linked
to agriculture abandonment and forestry specialization were the main processes observed in the study area, with the exception
of the southern mountainous sector that was dominated by ploughing of scrubland for conversion into grassland, reflecting
a specialization in livestock production. The structural changes that have taken place in most of the study area were related
to the heterogeneity aspects, although the mountainous sectors were characterized by changes in heterogeneity and fragmentation.
According to the tests performed, the comparison of the spatial distribution of both dynamics showed a certain statistical
significance, reflecting the interrelationship between patterns and processes. This approach could be useful for the identification
of areas with similar characteristics in terms of spatial dynamics so as to define more effective and targeted landscape planning
and management strategies. 相似文献
12.
Itziar de Aranzabal María F. Schmitz Francisco D. Pineda 《Environmental management》2009,44(5):938-951
Tourism and landscape are interdependent concepts. Nature- and culture-based tourism are now quite well developed activities
and can constitute an excellent way of exploiting the natural resources of certain areas, and should therefore be considered
as key objectives in landscape planning and management in a growing number of countries. All of this calls for careful evaluation
of the effects of tourism on the territory. This article focuses on an integrated spatial method for landscape analysis aimed
at quantifying the relationship between preferences of visitors and landscape features. The spatial expression of the model
relating types of leisure and recreational preferences to the potential capacity of the landscape to meet them involves a
set of maps showing degrees of potential visitor satisfaction. The method constitutes a useful tool for the design of tourism
planning and management strategies, with landscape conservation as a reference. 相似文献
13.
Dorcas H. Franklin Jean L. Steiner Sara E. Duke Daniel N. Moriasi Patrick J. Starks 《Journal of the American Water Resources Association》2013,49(4):908-922
The Fort Cobb Watershed in Oklahoma has diverse biogeophysical settings and provides an opportunity to explore the association of water quality with a diverse set of landscapes during both wet (April 2007‐December 2009) and dry (January 2005‐March 2007) periods. The objective of this work was to identify spatial patterns in phosphorus (P) (soluble reactive P [SRP] and bioavailable P [BAP]) associated with landscape metrics for two distinct streamflow regimes. Spatial autocorrelation of P was evaluated using contiguous (side‐by‐side) and upstream (upstream:downstream) connectivity matrices. Biogeophysical metrics were compiled for each contributing area, and were partitioned based on association to P concentrations. Results for both SRP and BAP indicated that spatial autocorrelation was present (p < 0.05). There was more spatial autocorrelation and stream P concentrations were three to five times higher in the Wet phase than in the Dry phase (p < 0.05). Analysis with recursive partitioning resulted in higher R2 with spatial autocorrelation than without spatial autocorrelation and indicated that lateral metrics (topography, soil, geology, management) were better predictors for SRP than instream metrics. During Wet phase, lateral metrics indicative of rapid surface and subsurface water movement were associated with higher P stream concentrations. This research demonstrated that we can detect landscapes more vulnerable to P losses and/or contaminations in either drought or very wet periods. 相似文献
14.
Many ecologists focus on the effects of roads on landscapes, yet few consider how landscapes affect road systems. In this
study, therefore, we quantitatively evaluated how land cover, topography, and building density affected the length density,
node density, spatial pattern, and location of roads in Dongzhi Yuan, a typical loess region in China. Landscape factors and
roads were mapped using images from SPOT satellite (Système Probatoire d’Observation de la Terre), initiated by the French
space agency and a digital elevation model (DEM). Detrended canonical correspondence analysis (DCCA), a useful ordination
technique to explain species–environment relations in community ecology, was applied to evaluate the ways in which landscapes
may influence roads. The results showed that both farmland area and building density were positively correlated with road
variables, whereas gully density and the coefficient of variation (CV of DEM) showed negative correlations. The CV of DEM,
farmland area, grassland area, and building density explained variation in node density, length density, and the spatial pattern
of roads, whereas gully density and building density explained variation in variables representing road location. In addition,
node density, rather than length density, was the primary road variable affected by landscape variables. The results showed
that the DCCA was effective in explaining road–landscape relations. Understanding these relations can provide information
for landscape managers and transportation planners. 相似文献
15.
Petit S 《Journal of environmental management》2009,90(9):2851-2856
Rural landscapes are highly dynamic and their change impacts on a number of ecological processes such as the dynamics of biodiversity. Although a substantial amount of research has focused on quantifying these changes and their impact on biodiversity, most studies have focused on single dimensions of land use change. This lack of integration in land use change studies can be explained by the fact that data on the spatial, temporal, and ecological dimensions of land use are seldom available for the same geographical location. In this paper, the benefits of taking into account these three dimensions are illustrated with results derived from the Great Britain Countryside Surveys (CS), a large-scale monitoring programme designed to assess change in the extent and ecological condition of British habitats. The overview of CS results presented in this paper shows that (1) changes in land use composition will translate into a variety of spatial patterns; (2) the temporal stability of land use is often lower than can be expected; and (3) there can be large-scale shifts in the ecological condition of the land use types that form our rural landscapes. The benefits of integrated rural landscape studies are discussed in the context of other national monitoring programmes. 相似文献
16.
Rocío Pérez-Campaña Luis Miguel Valenzuela-Montes 《Journal of Environmental Planning and Management》2018,61(3):406-429
The ecological value of some fine-scale landscape elements tends to be overlooked when they are found in highly human-influenced landscapes, such as peri-urban agricultural ones. These landscapes usually fall beyond the scope of the defined categories of landscape protection, and are thus mapped as areas of little or no ecological interest in the context of extensive analysis. In this paper, we present a method for assessing and visualizing the existing nodes in the field pattern of a peri-urban agricultural landscape. Nodes are identified from the field pattern and characterized according to the presence of relevant features and land uses from the viewpoint of their ecological functions. The method is applied in the Vega del Guadalfeo (south of Spain). Our results show an innovative map of the Vega which may be interpreted as its eco-structure; a model based on nodes to represent the ecological value of the peri-urban agricultural landscape. 相似文献
17.
A Spatially Explicit Resource-Based Approach for Managing Stream Fishes in Riverscapes 总被引:1,自引:0,他引:1
The article describes a riverscape approach based on landscape ecology concepts, which aims at studying the multiscale relationships
between the spatial pattern of stream fish habitat patches and processes depending on fish movements. A review of the literature
shows that few operational methods are available to study this relationship due to multiple methodological and practical challenges
inherent to underwater environments. We illustrated the approach with literature data on a cyprinid species (Barbus barbus) and an actual riverscape of the Seine River, France. We represented the underwater environment of fishes for different discharges
using two-dimensional geographic information system-based maps of the resource habitat patches, defined according to activities
(feeding, resting, and spawning). To quantify spatial patterns at nested levels (resource habitat patch, daily activities
area, subpopulation area), we calculated their composition, configuration, complementation, and connectivity with multiple
spatial analysis methods: patch metrics, moving-window analysis, and least cost modeling. The proximity index allowed us to
evaluate habitat patches of relatively great value, depending on their spatial context, which contributes to the setting of
preservation policies. The methods presented to delimit potential daily activities areas and subpopulation areas showed the
potential gaps in the biological connectivity of the reach. These methods provided some space for action in restoration schemes. 相似文献
18.
Agricultural expansion and deforestation are spatial processes of land transformation that impact on landscape pattern. In
peninsular Malaysia, the conversion of forested areas into two major cash crops—rubber and oil palm plantations—has been identified
as driving significant environmental change. To date, there has been insufficient literature studying the link between changes
in landscape patterns and land-related development policies. Therefore, this paper examines: (i) the links between development
policies and changes in land use/land cover and landscape pattern and (ii) the significance and implications of these links
for future development policies. The objective is to generate insights on the changing process of land use/land cover and
landscape pattern as a functional response to development policies and their consequences for environmental conditions. Over
the last century, the development of cash crops has changed the country from one dominated by natural landscapes to one dominated
by agricultural landscapes. But the last decade of the century saw urbanization beginning to impact significantly. This process
aligned with the establishment of various development policies, from land development for agriculture between the mid 1950s
and the 1970s to an emphasis on manufacturing from the 1980s onward. Based on a case study in Selangor, peninsular Malaysia,
a model of landscape pattern change is presented. It contains three stages according to the relative importance of rubber
(first stage: 1900–1950s), oil palm (second stage: 1960s–1970s), and urban (third stage: 1980s–1990s) development that influenced
landscape fragmentation and heterogeneity. The environmental consequences of this change have been depicted through loss of
biodiversity, geohazard incidences, and the spread of vector-borne diseases. The spatial ecological information can be useful
to development policy formulation, allowing diagnosis of the country’s “health” and sustainability. The final section outlines
the usefulness of landscape analysis in the policy-making process to prevent further fragmentation of the landscape and forest
loss in Malaysia in the face of rapid economic development.
相似文献
Adnan A. HezriEmail: |
19.
Landscape Changes in the Mullica River Basin of the Pinelands National Reserve,New Jersey,USA 总被引:1,自引:0,他引:1
In 1979, the Pinelands Commission was established as a regional land-use planning and regulatory agency charged with the implementation of a Comprehensive Management Plan (CMP) for the Pinelands National Reserve (New Jersey, USA). The CMP was created to balance land preservation and development interests in the Reserve. Because water-quality degradation from developed and agricultural landscapes is associated with changes in the composition of biological communities, monitoring landscape changes provides one of the most direct measures of the impact of land-use policies on the Pinelands ecosystem. In this study, we prepared detailed, land-cover maps within randomly selected aerial-photograph plots for a major watershed in the Reserve. We used these land-cover maps to quantify changes in landscape composition and structure (i.e., patch size, patch area, and number of patches) and characterize land-cover transitions in the basin between 1979 and 1991. Because the study period represented the first 12 years of the regional-planning effort in the Reserve, we evaluated the relationship between land-cover transitions and Commission management-area designations which permit different land-use intensities. Although the landscape composition was similar in 1979 and 1991, we found an increase in the total area and number of developed-land, managed-grassland, and barren-land patches. An increase in the number of patches and a decrease in the total area and median and third-quartile patch sizes for forest land and for all patches regardless of cover type indicated that fragmentation of forest land and the landscape as a whole occurred during the study period. The major land-cover transitions that occurred during the period were the loss of forest land to development and associated cover types and the conversion of one agricultural type to another. Overall, land-cover transitions during the period were found to be consistent with the Commission management-area designations, which indicated that the regional-planning effort has been successful in directing human activities to appropriate areas of the basin. 相似文献
20.
Landscape Characterization Integrating Expert and Local Spatial Knowledge of Land and Forest Resources 总被引:1,自引:1,他引:0
In many developing countries, political documentation acknowledges the crucial elements of participation and spatiality for effective land use planning. However, operative approaches to spatial data inclusion and representation in participatory land management are often lacking. In this paper, we apply and develop an integrated landscape characterization approach to enhance spatial knowledge generation about the complex human–nature interactions in landscapes in the context of Zanzibar, Tanzania. We apply an integrated landscape conceptualization as a theoretical framework where the expert and local knowledge can meet in spatial context. The characterization is based on combining multiple data sources in GIS, and involves local communities and their local spatial knowledge since the beginning into the process. Focusing on the expected information needs for community forest management, our characterization integrates physical landscape features and retrospective landscape change data with place-specific community knowledge collected through participatory GIS techniques. The characterization is established in a map form consisting of four themes and their synthesis. The characterization maps are designed to support intuitive interpretation, express the inherently uncertain nature of the data, and accompanied by photographs to enhance communication. Visual interpretation of the characterization mediates information about the character of areas and places in the studied local landscape, depicting the role of forest resources as part of the landscape entity. We conclude that landscape characterization applied in GIS is a highly potential tool for participatory land and resource management, where spatial argumentation, stakeholder communication, and empowerment are critical issues. 相似文献