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Nicholas A. O. Hill Dilys Roe J. Marcus Rowcliffe Noëlle F. Kümpel Mike Day Francesca Booker E. J. Milner‐Gulland 《Conservation biology》2016,30(1):7-13
Alternative livelihood project (ALP) is a widely used term for interventions that aim to reduce the prevalence of activities deemed to be environmentally damaging by substituting them with lower impact livelihood activities that provide at least equivalent benefits. ALPs are widely implemented in conservation, but in 2012, an International Union for Conservation of Nature resolution called for a critical review of such projects based on concern that their effectiveness was unproven. We focused on the conceptual design of ALPs by considering their underlying assumptions. We placed ALPs within a broad category of livelihood‐focused interventions to better understand their role in conservation and their intended impacts. We dissected 3 flawed assumptions about ALPs based on the notions of substitution, the homogenous community, and impact scalability. Interventions based on flawed assumptions about people's needs, aspirations, and the factors that influence livelihood choice are unlikely to achieve conservation objectives. We therefore recommend use of a sustainable livelihoods approach to understand the role and function of environmentally damaging behaviors within livelihood strategies; differentiate between households in a community that have the greatest environmental impact and those most vulnerable to resource access restrictions to improve intervention targeting; and learn more about the social–ecological system within which household livelihood strategies are embedded. Rather than using livelihood‐focused interventions as a direct behavior‐change tool, it may be more appropriate to focus on either enhancing the existing livelihood strategies of those most vulnerable to conservation‐imposed resource access restrictions or on use of livelihood‐focused interventions that establish a clear link to conservation as a means of building good community relations. However, we recommend that the term ALP be replaced by the broader term livelihood‐focused intervention. This avoids the implicit assumption that alternatives can fully substitute for natural resource‐based livelihood activities. 相似文献
383.
Collado Sergio Oulego Paula Alonso Saúl Díaz Mario 《Environmental science and pollution research international》2017,24(26):21262-21271
Environmental Science and Pollution Research - Flow cytometry has recently been presented as a research tool in the assessment of the viability/activity of activated sludge from municipal... 相似文献
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Béatrice Gaume Martine Fouchereau-Peron Aïcha Badou Marie-Noëlle Helléouet Sylvain Huchette Stéphanie Auzoux-Bordenave 《Marine Biology》2011,158(2):341-353
Larval shell formation was investigated in the European abalone Haliotis tuberculata. Stages of mineralization as well as enzymatic and endocrine biomarkers were monitored throughout larval development, from
hatching to post-larval stages. Polarized light microscopy and infrared spectroscopy analyses revealed the presence of crystallized
calcium carbonate arranged in aragonite polymorphs from the late trochophore stage. A correlation between the main steps of
shell formation and enzymatic activities of alkaline phosphatase and carbonic anhydrase was seen. The variations of these
biologic activities were related to the onset of mineralization, the rapid shell growth, and the switch from larval to juvenile
shell following metamorphosis. Furthermore, a strong increase in the level of calcitonin gene-related molecules was measured
in post-larvae, suggesting that endocrine control takes place after metamorphosis. The changes measured for the three biomineralization
markers together with mineralogical analysis allowed us to correlate physiologic mechanisms with early steps of abalone shell
formation. 相似文献
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This paper analyses biofuels from agricultural crops in northern Europe regarding area and energy efficiency, greenhouse gases and eutrophication. The overall findings are that direct land use changes have a significant impact on GHG balances and eutrophication for all biofuels, the choice of calculation methods when by-products are included affecting the performance of food crop-based biofuels considerably, and the technical design of production systems may in specific cases be of major importance. The presented results are essential knowledge for the development of certification systems. Indirect land use changes are recognised but not included due to current scientific and methodological deficiencies. 相似文献
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Aykan Karademir Halim Aytekin Ergül Bircan Telli Seda Aslan Kılavuz Mine Terzi 《Environmental science and pollution research international》2013,20(9):6611-6619
This study evaluates PCDD/F pollution in the surface sediments of Izmit Bay (Turkey) and assesses the possible sources of PCDD/F inputs to the bay. The results showed that concentrations of toxic PCDD/F congeners in the sediments varied between 0.45 and 255 ng WHO2005-TEQ/kg dry weight. Pollution mapping shows that PCDD/F levels in the central section of Izmit Bay are much higher than those in the eastern and the western sections. Sediments collected from the northern part of the central section showed very high PCDD/F concentrations. The samples reveal three different congener profiles dominated by OCDF, 1,2,3,4,6,7,8-HpCDF, and OCDD respectively. The dominance of OCDF in the sediment samples taken from the central section was attributed to the former production of vinyl chloride monomer in the area, while that of 1,2,3,4,6,7,8-HpCDF was attributed to the (previously unknown) use of a chlorophenol-based fungicide in the region. The OCDD dominated group was explained by the use of pentachlorophenol. The results indicate that historic industrial discharges are the main contributor to the PCDD/F pollution in the sediments. 相似文献