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1.
Abstract: The new approaches advocated by the conservation community to integrate conservation and livelihood development now explicitly address landscape mosaics composed of agricultural and forested land rather than only protected areas and largely intact forests. We refer specifically to a call by Harvey et al. (2008) to develop a new approach based on six strategies to integrate biodiversity conservation with sustainable livelihoods in Mesoamerican landscape mosaics. We examined the applicability of this proposal to the coffee agroforests of the Western Ghats, India. Of the six strategies, only one directly addresses livelihood conditions. Their approach has a clear emphasis on conservation and, as currently formulated risks repeating the failures of past integrated conservation and development projects. It fails to place the aspirations of farmers at the core of the agenda. Thus, although we acknowledge and share the broad vision and many of the ideas proposed by this approach, we urge more balanced priority setting by emphasizing people as much as biodiversity through a careful consideration of local livelihood needs and aspirations.  相似文献   

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Abstract:  Although sacred groves are important for conservation in India, the landscape that surrounds them has a vital influence on biodiversity within them. Research has focused on tree diversity inside these forest patches. In a coffee-growing region of the Western Ghats, however, landscape outside sacred groves is also tree covered because planters have retained native trees to provide shade for coffee plants. We examined the diversity of trees, birds, and macrofungi at 58 sites—10 forest-reserve sites, 25 sacred groves, and 23 coffee plantations— in Kodagu district. We measured landscape composition and configuration around each site with a geographic information system. To identify factors associated with diversity we constructed multivariate models by using a decision-tree technique. The conventional measures of landscape fragmentation such as patch size did not influence species richness. Distance of sacred groves from the forest reserve had a weak influence. The measures of landscape structure (e.g., tree cover in the surroundings) and stand structure (e.g., variability in canopy height) contributed to the variation in species richness explained by multivariate models. We suggest that biodiversity present within sacred groves has been influenced by native tree cover in the surrounding landscape. To conserve this biodiversity the integrity of the tree-covered landscape matrix will need to be conserved.  相似文献   

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Abstract:  Large wild fires occurring in forests, grasslands, and chaparral in the last few years have aroused much public concern. Many have described these events as "catastrophes" that must be prevented through aggressive increases in forest thinning. Yet the real catastrophes are not the fires themselves but those land uses, in concert with fire-suppression policies that have resulted in dramatic alterations to ecosystem structure and composition. The first step in the restoration of biological diversity (forest health) of western landscapes must be to implement changes in those factors that have caused degradation or are preventing recovery. This includes changes in policies and practices that have resulted in the current state of wildland ecosystems. Restoration entails much more than simple structural modifications achieved though mechanical means. Restoration should be undertaken at landscape scales and must allow for the occurrence of dominant ecosystem processes, such as the natural fire regimes achieved through natural and/or prescribed fires at appropriate temporal and spatial scales.  相似文献   

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Abstract

This study reports on new particle formation (NPF) and characteristic features observed from a rural site falling in the rainshadow of the Western Ghats in peninsular India. A total of 35 NPF events observed during August 2018 - January 2019 are classified and analyzed here. The apparent formation rates ranged from 0.2 to 10.0?cm–3 s–1, while the growth rates of nucleation mode particles ranged from 1.2 to 13.8?nm h–1. The frequency of occurrence was least during August (core monsoon) and highest during post-monsoon. The local winds were calm and southeasterly to easterly (from the urban centre) supplying the essential precursor gases during October and November, leading to a frequent occurrence of nucleation events. Observations suggest that an increased condensation sink could limit the NPF while promoting Aitken mode growth. The newly formed particles accounted for about 10–80% of the total aerosol concentration. These newly formed particles were able to act as cloud condensation nuclei after growing to approximately 50?nm with an average activation fraction of 0.4.  相似文献   

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Correlations and cross-correlations between forest fires in the province of British Columbia, Canada, and sea surface temperatures in the Pacific Ocean were evaluated. British Columbia has a long Pacific Ocean coastline; given that there may be teleconnections between the province's forest fires and climate variability over the ocean, significant correlations may exist between forest fires and the sea surface temperature of the Pacific Ocean. Fire occurrences and areas burned through lightning-caused and human-caused fires were analyzed against individual 1° × 1° grid cells of anomalies in the sea surface temperature to determine correlations for the period 1950-2006. Significant correlations (p < 0.05) for vast areas of the ocean were found between occurrences of lightning-caused fires and sea surface temperature anomalies for time lags of 1 and 2 years, whereas significant correlations between occurrences of human-caused fires and sea surface temperature anomalies occurred extensively for many time lags. To support the results of this approach, correlations between fire data and the Niño 3.4, Pacific Decadal Oscillation, and Arctic Oscillation indices were tested for the same period. Significant correlations were found between fire occurrences and these indices at certain time lags. Overall, fire occurrence appeared to be more extensively correlated with sea surface temperature anomalies than was area burned. These results support the hypothesis that teleconnections exist between fire activity in British Columbia and sea surface temperatures in the Pacific Ocean, and the correlations suggest that linear regression models or other regression techniques may be appropriate for predicting fire severity from the sea surface temperatures of one or more previous years.  相似文献   

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The formation of ultrafine particles, their growth, and associated characteristic features has been studied during new particle formation events over a high-altitude station of the Western Ghats during the 2014 post-monsoon season. Most of the events were observed during noon time where particle bursts in the nucleation-mode size range from 5 to 25 nm followed by sustained growth in size. This phenomenon persists for ~4–8 h with a growth rate of 1–2 nm h1. Peak concentrations of nucleation-mode particles during the event generally vary from 2300 to 5000 cm3. The mean growth rate is 1.4 ± 0.42 nm h1, particle formation rate is 1.14 ± 0.22 cm3 s1, coagulation sink is 0.35 ± 0.22 cm3 s1, and condensational sink is 15.4 ± 2.6?×?103 s1. All these values are comparable with earlier results from Indian region. Comparison of size-segregated particle number concentration during days of new particle formation events and those without new particle formation were carried out showing a distinct variation in nucleation and Aitken mode with least variability associated with the accumulation mode.  相似文献   

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Abstract: Populations of wolves were estimated for the states of Gujarat and Rajasthan, India, based on interviews and surveys. The wolf range is continuous. The total number of wolves in Gujarat is between 190 and 270 and in Rajasthan is between 253 and 350. Recommendations for a wolf conservation strategy include: (1) encouraging public support and education, (2) enforcing legal protection, (3) paying compensation for wolf-killed livestock, (4) conducting surveys of wolf populations and research on the dynamics of select populations, (5) protecting breeding habitats, and (6) eradicating feral dogs from wolf conservation areas. It is not too late to save the wolf if such a conservation strategy is implemented immediately.  相似文献   

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Most species face multiple anthropogenic disruptions. Few studies have quantified the cumulative influence of multiple threats on species of conservation concern, and far fewer have quantified the potential relative value of multiple conservation interventions in light of these threats. We linked spatial distribution and population viability models to explore conservation interventions under projected climate change, urbanization, and changes in fire regime on a long‐lived obligate seeding plant species sensitive to high fire frequencies, a dominant plant functional type in many fire‐prone ecosystems, including the biodiversity hotspots of Mediterranean‐type ecosystems. First, we investigated the relative risk of population decline for plant populations in landscapes with and without land protection under an existing habitat conservation plan. Second, we modeled the effectiveness of relocating both seedlings and seeds from a large patch with predicted declines in habitat area to 2 unoccupied recipient patches with increasing habitat area under 2 projected climate change scenarios. Finally, we modeled 8 fire return intervals (FRIs) approximating the outcomes of different management strategies that effectively control fire frequency. Invariably, long‐lived obligate seeding populations remained viable only when FRIs were maintained at or above a minimum level. Land conservation and seedling relocation efforts lessened the impact of climate change and land‐use change on obligate seeding populations to differing degrees depending on the climate change scenario, but neither of these efforts was as generally effective as frequent translocation of seeds. While none of the modeled strategies fully compensated for the effects of land‐use and climate change, an integrative approach managing multiple threats may diminish population declines for species in complex landscapes. Conservation plans designed to mitigate the impacts of a single threat are likely to fail if additional threats are ignored. Manejo de Incendios, Reubicación Administrada y Opciones de Conservación de Suelo para Plantas de Vida Larga con Sembrado Obligado bajo los Cambios Globales en el Clima, la Urbanización y el Régimen de Incendios  相似文献   

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We aspired to set conservation priorities in ways that lead to direct conservation actions. Very large‐scale strategic mapping leads to familiar conservation priorities exemplified by biodiversity hotspots. In contrast, tactical conservation actions unfold on much smaller geographical extents and they need to reflect the habitat loss and fragmentation that have sharply restricted where species now live. Our aspirations for direct, practical actions were demanding. First, we identified the global, strategic conservation priorities and then downscaled to practical local actions within the selected priorities. In doing this, we recognized the limitations of incomplete information. We started such a process in Colombia and used the results presented here to implement reforestation of degraded land to prevent the isolation of a large area of cloud forest. We used existing range maps of 171 bird species to identify priority conservation areas that would conserve the greatest number of species at risk in Colombia. By at risk species, we mean those that are endemic and have small ranges. The Western Andes had the highest concentrations of such species—100 in total—but the lowest densities of national parks. We then adjusted the priorities for this region by refining these species ranges by selecting only areas of suitable elevation and remaining habitat. The estimated ranges of these species shrank by 18–100% after accounting for habitat and suitable elevation. Setting conservation priorities on the basis of currently available range maps excluded priority areas in the Western Andes and, by extension, likely elsewhere and for other taxa. By incorporating detailed maps of remaining natural habitats, we made practical recommendations for conservation actions. One recommendation was to restore forest connections to a patch of cloud forest about to become isolated from the main Andes. Establecimiento de Prioridades Prácticas para la Conservación de Aves en los Andes Occidentales de Colombia  相似文献   

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以大兴安岭地区不同年份火烧迹地土壤动物为研究对象,对火烧后不同恢复时间土壤动物群落多样性及相关指数的变化进行分析.结果表明,大型土壤动物的个体数、DIC指数、丰富度指数及优势度指数变化趋势均表现为火烧恢复初期迅速增加,然后缓慢增加并逐渐接近对比样地值;如果不考虑8 a迹地数据极大值的影响,中小型土壤动物的个体数、DIC指数、丰富度指数及优势度指数也大致呈现火烧恢复初期迅速增加,然后缓慢增长的趋势;在垂直方向上,大型土壤动物DIC指数、个体数及丰富度指数在0~5 cm最大,向上、向下减少,而中小型土壤动物的各项指数都是凋落物层最大,向下迅速减小;相关分析表明,大型和中小型土壤动物的个体数和丰富度指数与DIC指数都具有极高的相关性;群落相似性分析显示,各火烧迹地间土壤动物群落具有较高的相似性.图1表3参26  相似文献   

15.
To explore the complexity of temporal and spatial dynamics of an agricultural landscape under various external and internal driven scenarios, SimKat, an agent-based model, has been developed with the simulation computer program CORMAS. This model combines simplified bio-physical processes of land cover, regional dry-land salinity changes, rainfall impact on productivity, farm profitability and the complexity of land-use decisions of individual farmers in a dry-land agricultural catchment (no irrigation). In this model, simulated farmers formulate individual decisions dealing with land-use changes based on the combined performance of their past land cover productivity and market returns. The willingness to adapt to market drivers and the ability to maximize returns vary between farmers. In addition, farmers in the model can demonstrate various attitudes towards dry-land salinity mitigation as a consequence of experiencing and perceiving salinity on their farm, in the neighborhood or across the entire region. Consequently, farmers can adopt land cover strategies aimed at reducing dry-land salinity. Aggregating the simulated individual behavior of farmers combined with historical rainfall and market price records, reproduced similar aggregated trends of land-cover changes, regional salinity change and farm number decline as observed in the last 20 years in the subject region (Katanning, Western Australia). Using the model in an initial exploratory study on the impact of rainfall variability and change highlighted the importance of average rainfall decline and the widespread willingness of farmers to adapt perennial vegetation in their farming systems to combat regional dry-land salinity. Rainfall decline, as one of the observed consequences of climate change in this region, can also lead to prolonged sequences of dry seasons in the future. Adaptation by farmers to sequences of dry and wet seasons, rather than an average trend in rainfall, seems to be critical for farm survival in this region. Intensifying cropping during wet seasons to maximize farm returns can increase vulnerability in subsequent periods of dry seasons, in particular where alternative income from pasture and sheep production has been lost in the adaptation process.  相似文献   

16.
In the Kullu District, Himachal Pradesh, India, economic and urban growth, and diversification have increased pressure on forests and forest-based social-ecological systems. As in many Himalayan regions, livelihood sustainability is linked to forest resources, products and services. Recent development in the region, to which these systems may be vulnerable, brings into question environmental and livelihood sustainability. This paper examines the resilience of integrated systems of people and nature, or social-ecological systems, in the face of development pressures by evaluating a number of local and state-level institutional responses. Resilience, which describes the ability of the social-ecological systems to adapt to change by buffering shocks, improving self-organization and increasing capacity for learning, is an essential quality for sustainable development. Institutional responses which positively contribute to resilience and sustainability include the work of mahila mandals in forest management, adoption of Joint Forest Management (JFM) policies and practices, upholding rules, strengthening local institutions, establishing firewood depots and adopting alternative energy sources. Institutional failures brought about by the lack of rule enforcement and corruption erode resilience. The analysis of institutional responses helps to identify areas where capacity exists and areas in which capacity building is needed to produce resilient social-ecological systems and therefore, sustainable development.  相似文献   

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Abstract:  The U.S. Fish and Wildlife Service's recent recovery plan for one of the most carefully watched threatened species worldwide, the Northern Spotted Owl (Strix occidentalis caurina), recommended a major departure in conservation strategies in the northwestern United States. Due to concern about fire, the plan would switch from a reserve to a no-reserve strategy in up to 52% of the owl's range. Fuel treatments (e.g., thinning) at regular intervals also would occur on up to 65–70% of dry forests in this area. Estimations of fire risk, however, were based on less than a decade of data and an anecdotal assessment of a single, large fire. We found that decadal data are inherently too short, given infrequent large fires, to accurately predict fire risk and trends. Rates of high-severity fire, based on remote-sensing data, are far lower than reported in the plan and in comparison with the rate of old-forest recruitment. In addition, over a 22-year period, there has been no increase in the proportion of high-severity fire. Our findings refute the key conclusions of the plan that are the basis for major changes in conservation strategies for the Spotted Owl. The best available science is needed to address these strategies in an adaptive-management framework. From the standpoint of fire risk, there appears to be ample time for research on fire and proposed treatment effects on Spotted Owls before designing extensive management actions or eliminating reserves.  相似文献   

18.
Abstract: The Mediterranean Basin is a global hotspot of biodiversity. Hotspots are said to be experiencing a major loss of habitat, but an added risk could be the decline of some species having a special role in ecological relationships of the system. We reviewed the role of European rabbits (Oryctolagus cuniculus) as a keystone species in the Iberian Peninsula portion of the Mediterranean hotspot. Rabbits conspicuously alter plant species composition and vegetation structure through grazing and seed dispersal, which creates open areas and preserves plant species diversity. Moreover, rabbit latrines have a demonstrable effect on soil fertility and plant growth and provide new feeding resources for many invertebrate species. Rabbit burrows provide nest sites and shelter for vertebrates and invertebrates. In addition, rabbits serve as prey for a number of predators, including the critically endangered Iberian lynx (Lynx pardinus) and Spanish Imperial Eagle (Aquila adalberti). Thus, the Mediterranean ecosystem of the Iberian Peninsula should be termed “the rabbit's ecosystem.” To our knowledge, this is the first empirical support for existence of a multifunctional keystone species in a global hotspot of biodiversity. Rabbit populations have declined drastically on the Iberian Peninsula, with potential cascading effects and serious ecological and economic consequences. From this perspective, rabbit recovery is one of the biggest challenges for conservation of the Mediterranean Basin hotspot.  相似文献   

19.
The various indigenous uses and structure of chir pine forests were studied in Uttaranchal state of the Indian Republic. A questionnaire survey was conducted in 50 villages of Uttaranchal to gather information on the indigenous uses of chir pine. For the study of community composition and structure of chir pine forest, at least 15 quadrats of 10 x 10 m were selected randomly across various localities, and the number of individuals, along with other dominant tree and shrub species, were enumerated in each quadrat. About 10 indigenous uses of chir pine were prominent in Uttaranchal. Besides resin, an important non-wood product, different parts of chir pine, such as cones, trunk, stems, wood, leaves and bark, were used by the local people. Chir pine is a subject of the folklore and mythology of indigenous cultures in Uttaranchal. Chir pine forest formed three major communities in Uttaranchal viz., sal-pine (Shorea robusta-Pinus roxburghii), pine pure stands and oak-pine (Quercus leucho-trichophora-Pinus roxburghii). These communities sustained various multiple-use trees and shrubs along with various edible mushrooms (eg. Agaricus campestris, Morchella esculenta and Sparassis crispa). The results of this study are discussed in the light of chir pine conservation and management policies.  相似文献   

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川西亚高山森林土壤有机层碳、氮、磷储量特征   总被引:4,自引:0,他引:4  
同步研究了川西亚高山云杉林、冷杉林和白桦林生态系统土壤有机层(OL)和矿质层(MS)的有机碳、全氮及全磷储量特征.所有土壤剖面上的有机碳和易氧化有机碳含量均随土壤深度增加而降低,即未分解层<半分解层<完全分解层<腐殖质层<淀积层<母质层.云杉林、冷杉林和白桦林土壤有机层的有机碳储量分别为29.38(±1.28)thm-2、22.70(±1.20)thm-2和8.63(±0.95)thm-2,矿质土壤中分别为17.84(±1.92)thm-2、19.74(±1.76)thm-2和14.92(±1.64)thm-2.冷杉林和白桦林土壤剖面上的全氮和全磷含量大小顺序为半分解层<完全分解层<腐殖质层,但腐殖质层>淀积层>母质层.云杉林、冷杉林、白桦林土壤有机层的全氮储量分别为0.85(±0.11)thm-2、0.68(±0.06)thm-2和(0.36±0.03)thm-2,全磷储量分别为0.29(±0.03)thm-2、0.22(±0.03)thm-2和0.06(±0.02)thm-2.图2表2参22  相似文献   

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