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1.
Protected areas are extremely important for the long term viability of biodiversity in a densely populated country like India where land is a scarce resource. However, protected areas cover only 5% of the land area in India and in the case of large carnivores that range widely, human use landscapes will function as important habitats required for gene flow to occur between protected areas. In this study, we used photographic capture recapture analysis to assess the density of large carnivores in a human-dominated agricultural landscape with density >300 people/km2 in western Maharashtra, India. We found evidence of a wide suite of wild carnivores inhabiting a cropland landscape devoid of wilderness and wild herbivore prey. Furthermore, the large carnivores; leopard (Panthera pardus) and striped hyaena (Hyaena hyaena) occurred at relatively high density of 4.8±1.2 (sd) adults/100 km2 and 5.03±1.3 (sd) adults/100 km2 respectively. This situation has never been reported before where 10 large carnivores/100 km2 are sharing space with dense human populations in a completely modified landscape. Human attacks by leopards were rare despite a potentially volatile situation considering that the leopard has been involved in serious conflict, including human deaths in adjoining areas. The results of our work push the frontiers of our understanding of the adaptability of both, humans and wildlife to each other’s presence. The results also highlight the urgent need to shift from a PA centric to a landscape level conservation approach, where issues are more complex, and the potential for conflict is also very high. It also highlights the need for a serious rethink of conservation policy, law and practice where the current management focus is restricted to wildlife inside Protected Areas.  相似文献   

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Contested Landscapes: Movement, Exile and Place. Barbara Bender and Margot Winer, eds. Oxford: Berg Publishers, 2001. 320pp.  相似文献   

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Generation of Spatial Patterns in Boreal Forest Landscapes   总被引:2,自引:0,他引:2  
Boreal forests are composed of a few plant species with contrasting traits with respect to ecosystem functioning and spatial patterning. Early successional deciduous species, such as birch and aspen, disperse seeds widely, do not tolerate low light and nitrogen availabilities, have rapidly decaying litter, and are highly preferred by herbivores. These later succeed to conifers, such as spruce and fir, which disperse seeds locally, tolerate low light levels and low nitrogen availability, have litter that decays slowly, and are unpalatable to most mammalian herbivores. Although there are also early successional conifers, such as jack pine and Scots pine, the aspen-birch-spruce-fir successional sequence is the most common over much of North America, and (without fir) in Fennoscandia and Siberia. The course of succession in these forests is controlled partly by seed dispersal and selective foraging by mammalian herbivores. Both of these processes are spatially dynamic, but little is known about how their spatial dynamics may affect ecosystem processes, such as nitrogen cycling or productivity. We present spatially explicit models that demonstrate the following: (a) Spatially explicit seed dispersal results in more clumped distribution of tree species and persistence of greater paper birch biomass than uniform seed rain across the landscape. Such results are consistent with current spatially explicit population models of dispersal and coexistence. (b) With localized seed dispersal, the concentrations of available soil nitrogen are distributed in larger patches with sharp transitions from low to high nitrogen availability near patch edges. In contrast, with a uniform seed rain, the distribution of soil nitrogen availability was more uniform and “hotspots” were more localized. Thus, the spatial pattern of an ecosystem process (nitrogen cycling) is determined by seed dispersal and competition for light among competing populations. (c) A dispersing herbivore, such as moose, that selectively forages on early successional deciduous species with high quality litter, such as aspen or birch, and discriminates against late successional conifers, such as spruce or fir, imposes higher-order repeated patterns of plant species and biomass distribution on the landscape. Thus, seed dispersal and herbivore foraging correlate properties in adjacent patches but in different ways, and different spatial patterns emerge. Other processes, such as insect outbreaks, fire, and water flow, also may correlate properties between adjacent patches and result in additional patterns. Received 8 February 1999; accepted 28 May 1999.  相似文献   

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Agricultural landscapes can be characterized as a mosaic of habitat patches interspersed with hostile matrix, or as a gradient of patches ranging from suitable to unsuitable for different species. Arthropods moving through these landscapes encounter a range of edges, with different permeability. Patches of native vegetation in these landscapes may support natural enemies of crop pests by providing alternate hosts for parasitic wasps and/or acting as a source for predatory insects. We test this by quantifying species interactions and measuring movement across different edge-types. A high diversity of parasitoid species used hosts in the native vegetation patches, however we recorded few instances of the same parasitoid species using hosts in both the native vegetation and the crop (canola). However, we did find overall greater densities of parasitoids moving from native vegetation into the crop. Of the parasitoid groups examined, parasitoids of aphids (Braconidae: Aphidiinae) frequently moved from native vegetation into canola. In contrast, parasitoids of caterpillars (Braconidae: Microgastrinae) moved commonly from cereal fields into canola. Late season samples showed both aphids and parasitoids moving frequently out of native vegetation, in contrast predators moved less commonly from native vegetation (across the whole season). The season-long net advantage or disadvantage of native vegetation for pest control services is therefore difficult to evaluate. It appears that the different edge-types alter movement patterns of natural enemies more so than herbivorous pest species, and this may impact pest control services.  相似文献   

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An important issue in conservation planning is to study the distribution and abundance patterns of species in natural landscapes. Information of concordant and clumped species distribution pattertns can enhance attempts to focus conservation efforts in sites/areas preferred by various species. We compared bird species abundance, community composition and species distribution patterns in three large old-growth forest areas (size 40–120 km2) in northern boreal Finland on the basis of quantitative bird censuses. Total bird density and species composition, and mean density and variances of the most abundant species were highly similar between the three areas. Most of the bird species were distributed randomly within the areas and species preferring old-growth forests showed compensatory density variation without preference for any sub-area. Mean density of species preferring old-growth forests was significantly higher in the studied large old-growth forests than in smaller old-growth forests and was about threefold higher than regional density of species in a predominantly managed landscape matrix. Bird species preferring old-growth forests are probably not dependent on a certain specific part of a virgin boreal forest landscape but rather on the overall size of the high-quality and diverse old-growth forest area.  相似文献   

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Sufi studies in India have become increasingly popular in the last fifteen years, which has provided insight into Sufi thought and practice. However, many of these studies tend to deal with political and social issues in relation to Sufi movements and shrine culture. My analysis presents an innovative way of understanding how Sufis experience sacred landscapes, and differs markedly from other studies on Indian Sufism. My aim is to analyse how Sufis at the Nizamuddin shrine sensuously engage with the sacred landscape.  相似文献   

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Scale-specific patterns of resource distribution on landscapes entrain attributes of resident animal communities such that species body-mass distributions are organized into distinct aggregations. Species within each aggregation respond to resources over the same range of scale. This discontinuous pattern has predictive power: invasive species and extinct or declining species in landscapes subject to human transformation tend to be located at the edge of body-mass aggregations (P < 0.01), which may be transition zones between distinct ranges of scale. Location at scale breaks affords species great opportunity, but also potential crisis. Received 19 May 1998; accepted 24 November 1998  相似文献   

9.
Remodelling the methylome is a hallmark of mammalian development and cell differentiation. However, current knowledge of DNA methylation dynamics in human tissue specification and organ development largely stems from the extrapolation of studies in vitro and animal models. Here, we report on the DNA methylation landscape using the 450k array of four human tissues (amnion, muscle, adrenal and pancreas) during the first and second trimester of gestation (9,18 and 22 weeks). We show that a tissue-specific signature, constituted by tissue-specific hypomethylated CpG sites, was already present at 9 weeks of gestation (W9). Furthermore, we report large-scale remodelling of DNA methylation from W9 to W22. Gain of DNA methylation preferentially occurred near genes involved in general developmental processes, whereas loss of DNA methylation mapped to genes with tissue-specific functions. Dynamic DNA methylation was associated with enhancers, but not promoters. Comparison of our data with external fetal adrenal, brain and liver revealed striking similarities in the trajectory of DNA methylation during fetal development. The analysis of gene expression data indicated that dynamic DNA methylation was associated with the progressive repression of developmental programs and the activation of genes involved in tissue-specific processes. The DNA methylation landscape of human fetal development provides insight into regulatory elements that guide tissue specification and lead to organ functionality.  相似文献   

10.
In this research, an agent-based model (ABM) was developed to generate human movement routes between homes and water resources in a rural setting, given commonly available geospatial datasets on population distribution, land cover and landscape resources. ABMs are an object-oriented computational approach to modelling a system, focusing on the interactions of autonomous agents, and aiming to assess the impact of these agents and their interactions on the system as a whole. An A* pathfinding algorithm was implemented to produce walking routes, given data on the terrain in the area. A* is an extension of Dijkstra’s algorithm with an enhanced time performance through the use of heuristics. In this example, it was possible to impute daily activity movement patterns to the water resource for all villages in a 75 km long study transect across the Luangwa Valley, Zambia, and the simulated human movements were statistically similar to empirical observations on travel times to the water resource (Chi-squared, 95% confidence interval). This indicates that it is possible to produce realistic data regarding human movements without costly measurement as is commonly achieved, for example, through GPS, or retrospective or real-time diaries. The approach is transferable between different geographical locations, and the product can be useful in providing an insight into human movement patterns, and therefore has use in many human exposure-related applications, specifically epidemiological research in rural areas, where spatial heterogeneity in the disease landscape, and space-time proximity of individuals, can play a crucial role in disease spread.  相似文献   

11.
Partial migration is a pervasive albeit poorly studied phenomenon by which some individuals of a population migrate while others are residents. It has tremendous consequences on seasonal variations of population size/structure and therefore management. Using a multi-event capture-mark-recapture/recovery (CMR) approach, we assessed seasonal site occupancy, survival and site fidelity of a partially migratory diving duck, the Common pochard (Aythya ferina), in an area potentially including both local breeders and winter visitors. The modelling exercise indeed discriminated two different categories of individuals. First, locally breeding females which had a probability of being present in our study area during winter of 0.41. Females of this category were found to be more faithful to their breeding site than males (breeding site fidelity probabilities of 1 and 0.11, respectively). The second category of birds were winter visitors, which included adults of both sexes, whose probability of being present in the study area during the breeding season was nil, and young of both sexes with a 0.11 probability of being present in the area during the breeding season. All wintering individuals, among which there was virtually no locally breeding male, displayed a high fidelity to our study area from one winter to the next (0.41–0.43). Estimated annual survival rates differed according to age (adults 0.69, young 0.56). For both age classes mortality was higher during late winter/early spring than during summer/early winter. Our study is among the first to show how and under which conditions the multi-event approach can be employed for investigating complex movement patterns encountered in partial migrants, providing a convenient tool for overcoming state uncertainty. It also shows why studying patterns of probability of individual presence/movements in partial migrants is a key towards understanding seasonal variations in numbers.  相似文献   

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We echo viewpoints presented in recent publications from EcoHealth and other journals arguing for the need to understand linkages between human health, disease ecology, and landscape change. We underscore the importance of incorporating spatialities of human behaviors and perceptions in such analyses to further understandings of socio-ecological interactions mediating human health. We use Buruli ulcer, an emerging necrotizing skin infection and serious health concern in central Ghana, to illustrate our argument.  相似文献   

15.
Intra-specific Variations in the Movement Patterns of Marine Animals   总被引:1,自引:0,他引:1  
A wealth of information exists on the distribution and movementpatterns of marine animals, based chiefly on tagging experiments,research surveys and commercial catch records. Three basic patternsemerge from these studies: migration, dispersal and home range,with species-specific permutations on these patterns. This paperreviews and discusses some of the intra-specific variationson these general movement patterns. Variations may take theform of range expansions, manifestations of inter-annual variationin oceanographic conditions, population-specific patterns, andvariations apparently related to habitat quality, sex or age.  相似文献   

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《Plains anthropologist》2013,58(88):144-160
Abstract

The primary object of this study is to determine whether bison movements were seasonal and sufficiently regular to be considered migratory.  相似文献   

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