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221.
Implementing the UNCCD: Participatory challenges 总被引:1,自引:0,他引:1
Lindsay C. Stringer Mark S. Reed rew J. Dougill Mary K. Seely Martin Rokitzki 《Natural resources forum》2007,31(3):198-211
The United Nations Convention to Combat Desertification (UNCCD) emphasizes the need for public participation in land degradation assessment and rehabilitation. While participatory approaches are supported by a growing body of research and practice, meaningfully involving the people affected by land degradation is far from straightforward. This paper investigates the challenge of using the UNCCD as a guide to influence community participation in policy‐making and practice at national and local levels by analyzing experiences from three southern African countries. We show that the UNCCD represents a useful normative framework for addressing degradation problems, but that the participatory ethos is difficult to enact at the national level. Whilst there is increasing evidence that combining local and scientific knowledge using participatory mechanisms can deliver the benefits that the Convention strives to achieve, communication between researchers and practitioners, and those involved in implementing the UNCCD at the national level needs to be strengthened. Broad lessons and best practices in incorporating participatory practices into policy development are elucidated. Our case studies show that a range of mixed‐method, interdisciplinary approaches can enable policy‐makers and practitioners to meaningfully engage those who are affected by land degradation in its definition, assessment and rehabilitation. 相似文献
222.
Campbell PK Middleton EM McMurtrey JE Corp LA Chappelle EW 《Journal of environmental quality》2007,36(3):832-845
Current methods for large-scale vegetation monitoring rely on multispectral remote sensing, which has serious limitation for the detection of vegetation stress. To contribute to the establishment of a generalized spectral approach for vegetation stress detection, this study compares the ability of high-spectral-resolution reflectance (R) and fluorescence (F) foliar measurements to detect vegetation changes associated with common environmental factors affecting plant growth and productivity. To obtain a spectral dataset from a broad range of species and stress conditions, plant material from three experiments was examined, including (i) corn, nitrogen (N) deficiency/excess; (ii) soybean, elevated carbon dioxide, and ozone levels; and (iii) red maple, augmented ultraviolet irradiation. Fluorescence and R spectra (400-800 nm) were measured on the same foliar samples in conjunction with photosynthetic pigments, carbon, and N content. For separation of a wide range of treatment levels, hyperspectral (5-10 nm) R indices were superior compared with F or broadband R indices, with the derivative parameters providing optimal results. For the detection of changes in vegetation physiology, hyperspectral indices can provide a significant improvement over broadband indices. The relationship of treatment levels to R was linear, whereas that to F was curvilinear. Using reflectance measurements, it was not possible to identify the unstressed vegetation condition, which was accomplished in all three experiments using F indices. Large-scale monitoring of vegetation condition and the detection of vegetation stress could be improved by using hyperspectral R and F information, a possible strategy for future remote sensing missions. 相似文献
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Michael H. Thomas Terrill R. Hanson 《Journal of Environmental Planning and Management》2007,50(1):153-162
The introduction of potentially invasive species is a concern to the public and the aquaculture industry. Used to protect channel catfish from infectious trematode infestations, the non-indigenous black carp has been evaluated by the US Fish and Wildlife Service (USFWS) and deemed potentially ‘injurious’ under the terms of the Lacey Act. Consequently, the black carp may be restricted from interstate commerce and eventually removed from US waters. An alternative approach to evaluating the risks posed by invasive species is considered and compared to that used by the USFWS. Short of outright restriction, reasonable options for management of such invasive species probably exist, including better use of environmental assurance bonds and return-deposit models. 相似文献
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Summary In Kumaun Himalaya, India, 60 percent of the rural population is dependent on natural springs for water supply. The authors claim that substantial reductions in spring water discharges are due to losses in the indigenous oak forest coverage and its partial replacement by pine. Other factors, such as overall forest cover depletion and construction activities, combine to produce severe reductions in spring discharge rates.Drs Anil Singh and Ravindra Pande are members of academic staff at Kumaun University working in the Laboratory for Hydrological and Geomorphological Investigations in the Department of Geography. 相似文献
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This article addresses the development of an agricultural productivity equation for predicting new soil (neo-sol) plant growth potential in Clay County, Minnesota, USA. Soil factors examined in the study include percent organic matter, percent slope, percent rock fragments, hydraulic conductivity, electrical conductivity, pH, topographic position, available water-holding capacity, bulk density, and percent clay. Squared terms and two-factor interaction terms were also examined as possible regressors. A best equation was selected that had a multiple coefficient of determination of 0.7399 and has five significant regressors and intercept withP.0001. The regressors are hydraulic conductivity, percent slope squared, bulk density times percent rock fragments, electrical conductivity times percent rock fragments, and electrical conductivity times percent organic matter. The regressors predict soil suitability for a general crop model. The crops included in the model are wheat, oats, barley, soybeans, sugar beets, sunflowers, and grasses/legumes. 相似文献
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Summary Plants and animals were investigated to ascertain their- radioactivity values on both dune sites (machair) and inter-tidal sites on the western coast of Barra, Outer Hebrides, UK. Material in both habitats was clearly contaminated. The accumulation of-radioactivity through food webs to organisms such asNucella lapillus (dog whelk) in the inter-tidal sites and in sheep and cattle in terrestrial sites is described.Dr F.B. Pyatt is the Section Leader and Principal Lecturer in Ecology in the Department of Life Sciences at Trent Polytechnic. Dr E.H. Beaumont was previously Lecturer in Zoology at St Hugh's College, University of Oxford, Oxford, UK. 相似文献