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261.
REDD projects have received considerable attention for their potential to mitigate the effects of climatic change. However, the existing literature has been slow to assess the impacts of proposed REDD projects on the livelihoods of forest communities in the developing world, or the implications of these local realities for the success of REDD+ initiatives in general. This study presents ethnographic research conducted with communities within the April-Salomei pilot REDD+ Project in Papua New Guinea (PNG). Several cases of institutional biases and uneven power relationships have been exploited by local elites to prevent landowners from making free and informed choices about their involvement in the project, although landowners and local communities are well positioned to capture forthcoming project benefits. By underestimating the scale and impact of traditional shifting cultivation practices, the credibility of the REDD+ project design and the value of any future carbon credits are critically undermined. Based on the actual practices found in PNG, the authors' radical proposal is to call for a halt on REDD development in PNG while institutional enabling conditions are improved, comprehensive landowner consultations conducted, and detailed mapping and genealogical surveys of landowners completed. Without these developments, future REDD+ projects in PNG are unlikely to benefit either the global climate or local development.  相似文献   
262.
C.P. Pow became a significant part of my own academic journey from soon after I joined the National University of Singapore (NUS) in 1999. Our academic inspirations, interests and identities overlapped, and we had opportunities to co-teach and co-write. I use these overlaps and collaborations as a way into reflecting on Pow's work, mainly during the period up to when he received tenure at NUS in 2011. I focus on two substantive themes. The first has to do with how and why Pow approached the landscape of Singapore beyond the visual or the ‘seen’. The second theme concerns the origins, development and consolidation of Pow's contributions to examining urban Asia in ways that unsettle Anglo-American-derived generalizations.  相似文献   
263.
The state of Kerala in India is known for its active civil society and the massive decentralization campaign launched in 1996. However marginalization of tribal communities hampers the state's decentralized environmental management strategies. The proposed construction of a dam along the Chalakkudy River will displace two colonies of the Kadar tribe in Chalakkudy and Athirapilly towns, destroy habitats of local wildlife and devastate unique riverine vegetation endemic to the region. This brings to light issues of social and environmental justice as well as a wider responsibility to protect and preserve unique flora and fauna. The state's decentralization strategies, as they relate to tribal communities, lack consideration of local power distribution and cultural conditioning. This raises questions about the state's role in social justice as well as biodiversity conservation. In 2010 and 2011, the author's interviews in Chalakkudy and Athirapilly towns reveal that tribal communities perceive that their place in society restricts their contribution regarding natural resource management and use. The paper suggests that unless the culture of planning and decision making in the state are changed, decentralized strategies will be ineffective, resulting in a predominately top‐down approach towards natural resource management, and will negate Kerala's goal of democratic decentralization.  相似文献   
264.
We studied the microbial communities collected from hydrate-bearing sediments on the North Slope of Alaska to determine how abiotic variables (e.g., grain size, hydrate presence, formation fluid gases) may correspond to the type and distribution of microbes in the sediments. The cores were acquired from sub-permafrost, Eocene (46-55 million year old) sediments in the BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well within which hydrates are believed to have formed 1.5 mya. Forty samples, eight of which originally contained hydrates, were acquired from depths of ca. 606-666 m below land surface. Five drilling fluid samples acquired from the same depth range were included in the analysis as a control for possible contamination by drilling fluid microbes during the drilling and handling of cores. DNA was extracted from 15 samples (typically <1 ng DNA/g sediment was recovered) and then amplified using polymerase chain reaction with primers specific for bacterial and archaeal 16S rDNA genes, which indicates the likelihood that microbes were present in all analyzed samples. Only bacterial DNA amplicons were detected. Terminal-restriction fragment length polymorphism (T-RFLP) was used to measure bacterial diversity in the respective samples. Non-metric multidimensional scaling (NMS) was used to determine the abiotic variables that may have influenced bacterial diversity. NMS analysis revealed that the microbial taxa present in the sediment were distinct from the taxa present in the drilling fluids suggesting that the sediments were not contaminated by the drilling fluids. Multi-response permutation procedures (MRPP) found no significant difference between three sample groups identified a priori as being from within a hydrate zone, outside of hydrate zone, or on the edge of a hydrate/non-hydrate zone according to downhole nuclear magnetic resonance spectroscopy logs. However, among the several other abiotic parameters that were evaluated mud gas methane concentration and variables related to hydrate presence (e.g., chloride concentration, salinity, and resistivity) appeared to define the arrangement of microbial community signatures in plots resulting from NMS analysis. Communities from hydrate and non-hydrate layers each contained unique taxa as determined by the T-RFLP assay.  相似文献   
265.
Mangrove litter is a major source of organic matter for detrital food chains in many tropical coastal ecosystems, but scant attention has been paid to the substantial challenges in sampling and extrapolation of rates of litter fall. The challenges arise due to within-stand heterogeneity including incomplete canopy cover, and canopy that is below the high tide mark. We sampled litter monthly for three years at 35 sites across eight mapped communities in the macrotidal Darwin Harbour, northern Australia. Totals were adjusted for mean community canopy cover and the occurrence of canopy below the high tide mark. The mangroves of Darwin Harbour generate an estimated average of 5.0 t ha−1 yr−1 of litter. This amount would have been overestimated by 32% had we not corrected for limited canopy cover and underestimated by 11% had we not corrected for foliage that is below the high tide mark. Had we made neither correction, we would have overestimated litter fall by 17%. Among communities, rates varied 2.6-fold per unit area of canopy, and 3.9-fold among unit area of community. Seaward fringe mangroves were the most productive per unit of canopy area but the canopy was relatively open; Tidal creek forest was the most productive per unit area of community. Litter fall varied 1.1-fold among years and 2.0-fold among months though communities exhibited a range of seasonalities. Our study may be the most extensively stratified and sampled evaluation of mangrove litter fall in a tropical estuary. We believe our study is also the first such assessment to explicitly deal with canopy discontinuities and demonstrates that failure to do so can result in considerable overestimation of mangrove productivity.  相似文献   
266.
The science and management of marine resources is increasingly grappling with the use of ecosystem-based fisheries management. Though ecosystem-based fisheries management seeks to unite biological and sociocultural concerns into a holistic framework, people are often seen simply as external drivers of change. The technical questions that are often posed, such as the delineation of boundaries or the strategies of governance, are however more broadly questions concerning the social production of nature. This paper explores these issues by analyzing both the spatial fishing practices of different fishermen and the results of a series of workshops held in New England to solicit opinions about ecosystem-based fisheries management. The paper emphasizes teasing apart the human dimensions of fishing embedded in predominant notions such as fishing effort through more explicit consideration of spatially based resource dependencies and mutual constitution of society-nature.  相似文献   
267.
作为"破碎城市"的典型表征,西方学者对门禁社区持负面态度,然而门禁社区在不同区域的出现受制于当地的社会文化要素,并可能对当地产生不同的影响.本文试图探讨在中国特殊的社会文化背景下,门禁社区与周边社会经济地位较低邻里的联系和社会关系,并通过分析门禁社区居民的活动范围和围墙内外居民彼此间的态度和社会交往来探讨门禁社区的影响...  相似文献   
268.
The effects of elevated atmospheric carbon dioxide [CO2] on microbial communities in arid rhizosphere soils beneath Larrea tridentata were examined. Roots of Larrea were harvested from plots fumigated with elevated or ambient levels of [CO2] using Free-Air CO2 Enrichment (FACE) technology. Twelve bacterial and fungal rRNA gene libraries were constructed, sequenced and categorized into operational taxonomical units (OTUs). There was a significant decrease in OTUs within the Firmicutes (bacteria) in elevated [CO2], and increase in Basiomycota (fungi) in rhizosphere soils of plots exposed to ambient [CO2]. Phylogenetic analyses indicated that OTUs belonged to a wide range of bacterial and fungal taxa. To further study changes in bacterial communities, Quantitative Polymerase Chain Reaction (QPCR) was used to quantify populations of bacteria in rhizosphere soil. The concentration of total bacteria 16S rDNA was similar in conditions of enriched and ambient [CO2]. However, QPCR of Gram-positive microorganisms showed a 43% decrease in the population in elevated [CO2]. The decrease in representation of Gram positives and the similar values for total bacterial DNA suggest that the representation of other bacterial taxa was promoted by elevated [CO2]. These results indicate that elevated [CO2] changes structure and representation of microorganisms associated with roots of desert plants.  相似文献   
269.
地质成果是与矿产资源紧密相关的财产权利,对它的认识不能局限于地质成果的形成具有智力投入的特点。分析地质成果的价值及维护其价值的方式,可发现它是一种商业秘密,在权利形态上是一种矿产发现权,这种发现权区别于传统理论对发现权归属于身份权的认识。在资源消耗超前的新经济时代,地质成果项下的矿产发现权是一种典型的产权。  相似文献   
270.
许玉婷  吴文恒  李研  史海金  杨毕红 《热带地理》2022,42(12):2007-2019
文章构建外部建成环境、内部建成环境、社区综合感知、社区凝聚力、个体特征5个维度15个概念变量的分析框架,基于西安市企业社区建成环境兴趣点(POI)数据与社会调查数据,建立多层线性回归模型并进行中介效应检验,定量探究企业社区老年居民幸福感的建成环境影响。研究发现:企业社区老年居民幸福感整体水平一般,李克特5分制量表下平均得分为3.54。与日常生活密切相关的风景类、医疗类、公共设施类等外部环境场所的可达性是老年居民幸福感的促进因子,老年居民对居住条件、社区绿化配置、内部道路和景观的主观感知以及对社区的综合感知正向影响幸福感;社区综合感知在设施POI类型的熵指数、公共设施类场所可达性对老年居民幸福感的影响中发挥中介作用。最后,提出风景绿地空间建设、医疗服务站点完善与公共设施场所服务质量提升,以及居住环境优化、住房条件改善与社区养老护理机构建设等方面的建成环境改进建议。  相似文献   
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