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Marc Beno?t Davide Rizzo Elisa Marraccini Anna Camilla Moonen Mariassunta Galli Sylvie Lardon Hélène Rapey Claudine Thenail Enrico Bonari 《Landscape Ecology》2012,27(10):1385-1394
Landscape dynamics increasingly challenge agronomists to explain how and why agricultural landscapes are designed and managed by farmers. Nevertheless, agronomy is rarely included in the wide range of disciplines involved in landscape research. In this paper, we describe how landscape agronomy can help explain the relationship between farming systems and agricultural landscape dynamics. For this, we propose a conceptual model of agricultural landscape dynamics that illustrates the specific contribution of agronomy to landscape research. This model describes the relationship between three elements: farming practices, landscape patterns and natural resources. It can stimulate agronomists to deal with research issues in agricultural landscape dynamics and enhance the interdisciplinary integration of farming systems in wider landscape research. On these premises, we discuss the main research issues that will benefit from an active involvement of agronomy, to understand, but also to assess landscape dynamics and to design relevant decision support systems. 相似文献
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Quantifying the agricultural landscape and assessing spatio-temporal patterns of precipitation and groundwater use 总被引:2,自引:0,他引:2
Quantitative agricultural landscape indices are useful to describe functional relationships among climatic conditions, groundwater dynamics, soil properties and agricultural land use for mathematical models. We applied methods of regression statistics, variance component estimation and a Geographical Information System (GIS) to construct indices describing crops and soils and to establish functional relationships among these variables. This paper describes the development of indices and the partitioning of the spatial and temporal variation in groundwater models using the data from Tulare County, California, which was selected as the study area. Indices of ground surface elevation, total crop water demand, soil water infiltration rate, and soil production index explain 91% of the variation in average spring groundwater level. After relating spatial patterns of groundwater use to indices of crop and soil properties, we found that mean groundwater use is positively related to total crop water demand and soil water infiltration rate while the variation in groundwater use was negatively correlated with the crop water demand and soil water infiltration rate and positively related to soil water holding capacity. The spatial variation in groundwater use was largely influenced by crops and soil types while the temporal variation was not. We also found that groundwater use increased exponentially with decreasing annual precipitation for most townships. Based on these associations, groundwater use in each township can be forecast from relative precipitation under current methods of agricultural production. Although groundwater table depth is strongly affected by topography, the statistically significant indices observed in the model clearly show that agricultural land use influences groundwater table depth. These simple relationships can be used by agronomists to make water management decisions and to design alternative cropping systems to sustain agricultural production during periods of surface water shortages. 相似文献
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Väli Ülo Mirski Paweł Sein Gunnar Abel Urmas Tõnisalu Grete Sellis Urmas 《Landscape Ecology》2020,35(7):1667-1681
Landscape Ecology - Biodiversity is closely related to landscape heterogeneity, but both are difficult to evaluate directly. Apex predators, such as raptors, are potential surrogate indicators of... 相似文献
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Spatial dynamics of the knob-tailed gecko Nephrurus stellatus in a fragmented agricultural landscape
In fragmented landscapes, a species?? dispersal ability and response to habitat condition are key determinants of persistence. To understand the relative importance of dispersal and condition for survival of Nephrurus stellatus (Gekkonidae) in southern Australia, we surveyed 92 woodland remnants three times. This gecko favours early post-fire succession conditions so may be at risk of extinction in the long-unburnt agricultural landscape. Using N-mixture models, we compared the influence of four measures of isolation, patch area and two habitat variables on the abundance and occurrence of N. stellatus, while taking into account detection probability. Patch occupancy was high, despite the long-term absence of fire from most remnants. Distance to the nearest occupied site was the most informative measure of patch isolation, exhibiting a negative relationship with occupancy. Distance to a nearby conservation park had little influence, suggesting that mainland?Cisland metapopulation dynamics are not important. Abundance and occurrence were positively related to ?%-cover of spinifex (Triodia), indicating that niche-related factors may also contribute to spatial dynamics. Patterns of patch occupancy imply that N. stellatus has a sequence of spatial dynamics across an isolation gradient, with patchy populations and source-sink dynamics when patches are within 300?m, metapopulations at intermediate isolation, and declining populations when patches are separated by >1?C2?km. Considering the conservation needs of the community, habitat condition and connectivity may need to be improved before fire can be reintroduced to the landscape. We speculate that fire may interact with habitat degradation and isolation, increasing the risk of local extinctions. 相似文献
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Effects of interactive scale-dependent variables on beetle diversity patterns in a semi-arid agricultural landscape 总被引:3,自引:0,他引:3
Understanding species-diversity patterns in heterogeneous landscapes invites comprehensive research on how scale-dependent
processes interact across scales. We used two common beetle families (Tenebrionidae, detrivores; Carabidae, predators) to
conduct such a study in the heterogeneous semi-arid landscape of the Southern Judean Lowland (SJL) of Israel, currently undergoing
intensive fragmentation. Beetles were censused in 25 different-sized patches (500–40,000 m2). We used Fisher’s α and non-parametric extrapolators to estimate species diversity from 11,125 individuals belonging to
56 species. Patch characteristics (plant species diversity and cover, soil cover and degree of stoniness) were measured by
field transects. Spatial variables (patch size, shape, physiognomy and connectivity) and landscape characteristics were analyzed
by GIS and remote-sensing applications. Both patch-scale and landscape-scale variables affected beetle species diversity.
Path-analysis models showed that landscape-scale variables had the strongest effect on carabid diversity in all patches. The
tenebrionids responded differently: both patch-scale and landscape-scale variables affected species diversity in small patches,
while mainly patch-scale variables affected species diversity in large patches. Most of the paths affected species diversity
both directly and indirectly, combining the effects of both patch-scale and landscape-scale variables. These results match
the biology of the two beetle families: Tenebrionidae, the less mobile and more site-attached family, responded to the environment
in a fine-grained manner, while the highly dispersed Carabidae responded to the environment in a coarse-grained manner. We
suggest that understanding abiotic and biotic variable interactions across scales has important consequences for our knowledge
of community structure and species diversity patterns at large spatial scales. 相似文献
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Ronan Marrec Gaël Caro Paul Miguet Isabelle Badenhausser Manuel Plantegenest Aude Vialatte Vincent Bretagnolle Bertrand Gauffre 《Landscape Ecology》2017,32(12):2383-2398
Context
Agroecosystems are dynamic, with yearly changing proportions of crops. Explicit consideration of this temporal heterogeneity is required to decipher population and community patterns but remains poorly studied.Objectives
We evaluated the impact on the activity-density of two dominant carabid species (Poecilus cupreus and Anchomenus dorsalis) of (1) local crop, current year landscape composition, and their interaction, and (2) inter-annual changes in landscape composition due to crop rotations.Methods
Carabids were sampled using pitfall-traps in 188 fields of winter cereals and oilseed rape in three agricultural areas of western France contrasting in their spatial heterogeneity. We summarized landscape composition in the current and previous years in a multi-scale perspective, using buffers of increasing size around sampling locations.Results
Both species were more abundant in oilseed rape, and in landscapes with a higher proportion of oilseed rape in the previous year. P. cupreus abundance was negatively influenced by oilseed rape proportion in the current year landscape in winter cereals and positively by winter cereal proportion in oilseed rape. A. dorsalis was globally impacted at finer scales than P. cupreus.Conclusions
Resource concentration and dilution-concentration processes jointly appear to cause transient dynamics of population abundance and distribution among habitat patches. Inter-patch movements across years appear to be key drivers of carabids’ survival and distribution, in response to crop rotation. Therefore, the explicit consideration of the spatiotemporal dynamics of landscape composition can allow future studies to better evidence ecological processes behind observed species patterns and help developing new management strategies.8.
Clinton D. Francis Juan Paritsis Catherine P. Ortega Alexander Cruz 《Landscape Ecology》2011,26(9):1269-1280
Anthropogenic noise is becoming a dominant component of soundscapes across the world and these altered acoustic conditions
may have severe consequences for natural communities. We modeled noise amplitudes from gas well compressors across a 16 km2 study area to estimate the influence of noise on avian habitat use and nest success. Using species with noise responses representative
of other avian community members, across the study area we estimated gray flycatcher (Empidonax wrightii) and western scrub-jay (Aphelocoma californica) occupancy, and gray flycatcher nest success, which is highly dependent on predation by western scrub-jays. We also explore
how alternative noise management and mitigation scenarios may reduce area impacted by noise. Compressor noise affected 84.5%
of our study area and occupancy of each species was approximately 5% lower than would be expected without compressor noise.
In contrast, flycatcher nest success was 7% higher, reflecting a decreased rate of predation in noisy areas. Not all alternative
management and mitigation scenarios reduced the proportion of area affected by noise; however, use of sound barrier walls
around compressors could reduce the area affected by noise by 70% and maintain occupancy and nest success rates at levels
close to those expected in a landscape without compressor noise. These results suggest that noise from compressors could be
effectively managed and, because habitat use and nest success are only two of many ecological processes that may change with
noise exposure, minimizing the anthropogenic component of soundscapes should be a conservation priority. 相似文献
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Tappeiner Ulrike Leitinger Georg Zariņa Anita Bürgi Matthias 《Landscape Ecology》2021,36(8):2317-2328
Landscape Ecology - Landscape ecology early on developed the awareness that central objects of investigation are not stable over time and therefore the historical dimension must be included, or at... 相似文献
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David J. Augustine Marc R. Matchett Theodore P. Toombs Jack F. CullyJr. Tammi L. Johnson John G. Sidle 《Landscape Ecology》2008,23(3):255-267
Black-tailed prairie dogs (Cynomys ludovicianus) are a key component of the disturbance regime in semi-arid grasslands of central North America. Many studies have compared
community and ecosystem characteristics on prairie dog colonies to grasslands without prairie dogs, but little is known about
landscape-scale patterns of disturbance that prairie dog colony complexes may impose on grasslands over long time periods.
We examined spatiotemporal dynamics in two prairie dog colony complexes in southeastern Colorado (Comanche) and northcentral
Montana (Phillips County) that have been strongly influenced by plague, and compared them to a complex unaffected by plague
in northwestern Nebraska (Oglala). Both plague-affected complexes exhibited substantial spatiotemporal variability in the
area occupied during a decade, in contrast to the stability of colonies in the Oglala complex. However, the plague-affected
complexes differed in spatial patterns of colony movement. Colonies in the Comanche complex in shortgrass steppe shifted locations
over a decade. Only 10% of the area occupied in 1995 was still occupied by prairie dogs in 2006. In 2005 and 2006 respectively,
74 and 83% of the total area of the Comanche complex occurred in locations that were not occupied in 1995, and only 1% of
the complex was occupied continuously over a decade. In contrast, prairie dogs in the Phillips County complex in mixed-grass
prairie and sagebrush steppe primarily recolonized previously occupied areas after plague-induced colony declines. In Phillips
County, 62% of the area occupied in 1993 was also occupied by prairie dogs in 2004, and 12% of the complex was occupied continuously
over a decade. Our results indicate that plague accelerates spatiotemporal movement of prairie dog colonies, and have significant
implications for landscape-scale effects of prairie dog disturbance on grassland composition and productivity. These findings
highlight the need to combine landscape-scale measures of habitat suitability with long-term measures of colony locations
to understand the role of plague-affected prairie dogs as a grassland disturbance process.
The U.S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged. 相似文献
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Virginia H. Dale Keith L. Kline Stephen R. Kaffka J. W. A. Langeveld 《Landscape Ecology》2013,28(6):1111-1123
Agricultural sustainability considers the effects of farm activities on social, economic, and environmental conditions at local and regional scales. Adoption of more sustainable agricultural practices entails defining sustainability, developing easily measured indicators of sustainability, moving toward integrated agricultural systems, and offering incentives or imposing regulations to affect farmer behavior. Landscape ecology is an informative discipline in considering sustainability because it provides theory and methods for dealing with spatial heterogeneity, scaling, integration, and complexity. To move toward more sustainable agriculture, we propose adopting a systems perspective, recognizing spatial heterogeneity, integrating landscape-design principles and addressing the influences of context, such as the particular products and their distribution, policy background, stakeholder values, location, temporal influences, spatial scale, and baseline conditions. Topics that need further attention at local and regional scales include (1) protocols for quantifying material and energy flows; (2) standard specifications for management practices and corresponding effects; (3) incentives and disincentives for enhancing economic, environmental, and social conditions (including financial, regulatory and other behavioral motivations); (4) integrated landscape planning and management; (5) monitoring and assessment; (6) effects of societal demand; and (7) integrative policies for promoting agricultural sustainability. 相似文献
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Lacunarity indices as measures of landscape texture 总被引:23,自引:0,他引:23
Lacunarity analysis is a multi-scaled method of determining the texture associated with patterns of spatial dispersion (i.e., habitat types or species locations) for one-, two-, and three-dimensional data. Lacunarity provides a parsimonious analysis of the overall fraction of a map or transect covered by the attribute of interest, the degree of contagion, the presence of self-similarity, the presence and scale of randomness, and the existence of hierarchical structure. For self-similar patterns, it can be used to determine the fractal dimension. The method is easily implemented on the computer and provides readily interpretable graphic results. Differences in pattern can be detected even among very sparsely occupied maps. 相似文献
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Uroy Léa Alignier Audrey Mony Cendrine Foltête Jean-Christophe Ernoult Aude 《Landscape Ecology》2021,36(9):2487-2504
Landscape Ecology - Landscape connectivity plays a key role in determining the persistence of species inhabiting fragmented habitat patches. In dynamic landscapes, most studies measure connectivity... 相似文献
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Eastern grey squirrels (Sciurus carolinensis) and North American red squirrels (Tamiasciurus hudsonicus) were studied among wooded patches within an agricultural mosaic. Fifteen sites south of Ottawa, Canada, with differing landscape and local features were censused using tracking boards placed in a woods or wooded fencerow. Regression analyses of landscape compositional and physiognomic variables within a 1-km radius isolated the best predictors of grey and red squirrel abundance and activity. Grey squirrels were found in both small woods and fencerows in farm landscapes but were not found in large woods. A polynomial regression of wooded patch size explained 79% of the variance in grey squirrel abundance. Grey squirrel activity was correlated with the percent cover of soybeans in the landscape. Red squirrels were found in fencerows, small and large woods; activity was correlated with the percent cover of both woods and corn crop in the surrounding landscape. These results indicate that distributions of both species are influenced by multiple landscape elements, but that grey squirrels may rely on fragmented agricultural landscapes whereas red squirrels make more use of both native woodland and altered landscapes. 相似文献
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Context
Pasture-woodlands are semi-natural landscapes that result from the combined influences of climate, management, and intrinsic vegetation dynamics. These landscapes are sensitive to future changes in land use and climate, but our ability to predict the impact on ecosystem service provisioning is limited due to the disparate scales in time and space that govern their dynamics.Objectives
To develop a process-based model to simulate pasture-woodland landscapes and the provisioning of ecosystem services (i.e., livestock forage, woody biomass and landscape heterogeneity).Methods
We modified a dynamic forest landscape model to simulate pasture-woodland landscapes in Switzerland. This involved including an annual herbaceous layer, selective grazing from cattle, and interactions between grazing and tree recruitment. Results were evaluated within a particular pasture, and then the model was used to simulate regional vegetation patterns and livestock suitability for a ~198,000 ha landscape in the Jura Vaudois region.Results
The proportion of vegetation cover types at the pasture level (i.e., open, semi-open and closed forests) was well represented, but the spatial distribution of trees was only broadly similar. The entire Jura Vaudois region was simulated to be highly suitable for livestock, with only a small proportion being unsuitable due to steep slopes and high tree cover. High and low elevation pastures were equally suitable for livestock, as lower forage production at higher elevations was compensated by reduced tree cover.Conclusions
The modified model is valuable for assessing landscape to regional patterns in vegetation and livestock, and offers a platform to evaluate how climate and management impact ecosystem services.17.
Biological soil crust distribution is related to patterns of fragmentation and landuse in a dryland agricultural landscape of southern Australia 总被引:2,自引:0,他引:2
The dryland agricultural landscape of north-west Victoria, Australia, includes isolated remnants of eucalypt woodland that
are exposed to ongoing disturbance from sheep grazing and cropping activity. Biological soil crusts are a functionally important
feature of these woodland communities. We used a modern form of regression (boosted regression tree (BRT) models) to investigate
relationships between crust abundance and environmental and landscape variables. We also investigated whether the use of broad
morphological groups of crust organisms is more informative than simply measuring total crust cover. Remnant size was the
single most influential variable for crust abundance, with negligible crust cover in small patches (<5 ha). The BRT model
also identified relationships between crust abundance and available P, soil C and perennial grass. We argue that disturbance
from stock grazing and camping is the mechanism driving these relationships. Other variables related to crust abundance were
proximity to the windward edge, litter cover and tree cover. Morphological groups showed a differential response to some variables,
suggesting assessment of total cover may mask important patterns in community structure. Crust disturbance represents a serious
issue for maintenance of ecosystem function in the study region, particularly loss of crusts from small remnants because the
majority of remnants are small. 相似文献
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Effects of landscape patterns on biotic communities 总被引:4,自引:0,他引:4
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Creating landscape patterns by forest cutting: Ecological consequences and principles 总被引:2,自引:2,他引:0
Landscape structural characteristics, such as patch size, edge length, and configuration, are altered markedly when management regimes are imposed on primeval landscapes. The ecological consequences of clearcutting patterns were explored by using a model of the dispersed patch or checkerboard system currently practiced on federal forest lands in the western United States. Thresholds in landscape structure were observed on a gradient of percentages of landscape cutover. Probability of disturbance,e.g., wildfire and windthrow, and biotic components,e.g., species diversity and game populations, are highly sensitive to these structural changes. Altering the spatial configuration and size of clearcuts provides an opportunity to create alternative landscapes that differ significantly in their ecological characteristics. Both ecosystem and heterogeneous landscape perspectives are critical in resource management. 相似文献
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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