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1.
The glaciers in the Sanjiangyuan Nature Reserve of China (SNRC) are a significant water resource for the Yangtze,Yellow,and Mekong rivers.Based on Landsat Thematic Mapper(TM)/Operational Land Imager (OLI) images acquired in 2000,2010,and 2018,the outlines of glaciers in the SNRC were obtained by combining band ratio method with manual interpretation.There were 1714 glaciers in the SNRC in 2018,with an area of 2331.15±54.84 km2,an ice volume of 188.90±6.41 km3,and an average length of 1475.4±15 m.During 2000-2018,the corresponding values of glaciers decreased by 69,271.95±132.06 km2,18.59±8.83 km3,and 84.75±34 m,respectively.Glaciers in the Yangtze River source area witnessed the largest area loss (-154.45 km2),whereas glaciers in the Mekong River source area experienced the fastest area loss (-2.02%·a-1) and the maximum reduction of the average length (-125.82 m).Overall,the retreat of glaciers in the SNRC exhibited an accelerating trend.Especially,the loss rate of glacier area in the Yellow River source area in 2010-2018 was more than twice that in 2000-2010.The glacier change is primarily attributed to the significant rise in temperature during the ablation period.Some other factors including the size,orientation and terminus elevation of glaciers also contributed to the heterogeneity of glacier change.  相似文献   

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I.IntroductionTheGiantPanda(Ailuropodamelanoleuea)isanendangeredanimalspeciesintheworld.Thereareabout1000individualsleftandconfinedintheisolatedmountainareasinthesouthwesternpartofChina.Itsremaininghabitatcoversabout29,500km2[2,6,11].Humanencroachmentisconsidere…  相似文献   

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NGOs, government agencies, and green businesses proclaim water fund arrangements in Latin America as successful payments for ecosystem services (PES) systems. Associated success narratives emphasize that PES allows downstream ecosystem service beneficiaries to incentivize upstream land managers to pursue conservation activities. However, recent scholarship questions their on-the-ground influence. This article assesses the success narrative of Quito, Ecuador’s Fondo para la protección del Agua’s (FONAG) as a model water fund PES arrangement. Using a novel perceived directionality framework, the author compares the FONAG claims about its influence to ethnographic evidence from three participating rural communities. The findings suggest that statements of direct, causal influence on local conservation activities overlook local context and ignores nuance within the interactions between program incentives and in community activity. This study urges future assessments of PES arrangements to recognize complexities in political, economic, and social context.  相似文献   

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ABSTRACT

This article examines the stomachs of ruminant livestock as a site of biotechnological intervention and analyzes efforts to reengineer ruminant digestion as a case of the real subsumption of nature. The livestock industry’s capacity to increase production is constrained by available grazing land and concern about environmental consequences of ever-increasing livestock numbers. Ruminants are also a significant source of greenhouse gases and the mitigation of methane is a recognized priority within the global climate framework. The pursuit of “sustainable intensification” and new technological fixes have been identified as preferred responses to these constraints. The case of ruminant methane calls into question assumptions about the primacy of accumulation, rather than regulation, in driving the real subsumption of nature. The pursuit of technological fixes within biologically based industries may be motivated by a need to stabilize the conditions of production, and regulation itself can provide an impetus for the real subsumption of nature.  相似文献   

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Homestay tourism has begun to flourish throughout the country, becoming a model of tourism innovation and upgrading, and attracting increasing amounts of capital. Through the collection and analysis of tourist questionnaire data for key cities in the Yangtze River Delta, and based on the theory of tourists' perceived value,18 factors related to the perception of homestay tourism are examined. Through exploratory factor analysis, three main factors of facilities and environment perception, cultural experience perception and service value perception are extracted. Then, from the perspectives of each of these perceptions, this study determines the degree of support for homestay tourism development in the Yangtze River Delta, obtains the key factors that affect the development of homestay tourism, and constructs a structural equation model of tourist perception and the degree of homestay tourism support. By calculating the regression path of the structural equation, the standardized path coefficients of the facilities and environment perception, cultural experience perception and service value perception are found to be 0.724, 0.813 and 0.692, respectively. These three factors have a significant impact on the development of homestay tourism agglomeration. Positive facilities and environmental perception can effectively support the development of homestay tourism, while the cultural experience perception provides its basic condition, and the service value perception constitutes an important factor of homestay tourism development. To better guide the development of homestay tourism, attention must be paid to developing the tourism facilities and environment, to cultivating tourism cultural experiences, and to improving of tourism service value.  相似文献   

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The water of Bosten Lake was released to lower reaches of the Tarim River for 5 times from 2000 to 2002. The changes of total dissolved solid (TDS) and the major ions (SO4^2-, Cl^-, Na^-,Ca^2 , Mg^2- and HCO3^- ) were analyzed during this period. It was found out that TDS and the concentrations of the major ions initially and quickly increased and then decreased, but finally increased again. These changes were different at different distances from the river, which indicated that the groundwater changes relied on the distance from the river. In addition, the salt in groundwater was only diluted but not removed by the water. It was suggested that ecological measures should be sought to really promote the quality of the groundwater at the lower reaches of the Tarim River.  相似文献   

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人才是乡村地域空间发展的基础,鼓励在外务工人员回流就业是推进乡村振兴的重要举措,也是实现共同富裕的保证。论文采用多变量交互作用的模糊集定性比较分析方法,以乡村旅游地居民回流就业意愿为结果变量,构建地方参与、地方情感、感知获益、风险承受能力、政府信任、支持度为前因变量的研究模型,探索居民回流就业的驱动机制与多元影响路径。研究结果表明:(1)所有单项因素均不构成乡村旅游地居民回流就业的必要条件;(2)满足条件的组合路径共7条,总体一致性为0.876,总体覆盖率为0.862;(3)在所有路径组合中,支持度和政府信任出现的频率最高,包含地方情感的路径覆盖率较高;(4)7条路径构成了情感主导路径、信任主导路径、支持主导路径,以及知—情—意—行综合路径4大类路径模式;(5)当同时包含情感、信任、支持和参与因素时,路径具有最高解释力;(6)不同类型的乡村旅游地在回流就业影响路径上显示出差异。研究结论可为鼓励和吸引乡村旅游地在外务工人员回乡参与旅游发展提供参考,也可为更广泛的乡村地区鼓励人才回流提供理论依据。  相似文献   

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ABSTRACT

Drawing on a database of 193 football (soccer) grounds and 115 indoor arenas, as well as press releases and media reports associated with them, this study charts the diffusion of sporting and entertainment facility name sponsorship across metropolises, cities, towns, and smaller settlements in six European contexts. Our results show the emergence of naming rights deals in the 1990s, their peak in the mid-2000s, and the current situation with a steadier growth of name sponsorship. Thus far, the corporate re-branding of venues has remained less prevalent in Italy, Norway, and Scotland than in England and Wales, Finland, and above all Germany. In financing newly built venues, however, the corporatized landmark language in focus has become a practically invariable part of local growth, austerity and (re)branding policies. Despite voices of resistance in all regions studied here, pressure towards the corporate renaming of even hereditary, communally endorsed football stadiums is increasingly being felt by municipal and private-sector venue owners.  相似文献   

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Due to methodological challenges there are only a few studies that focus on macrophyte dynamics in large lakes despite their notable role in a lake’s ecosystem functioning. This study investigates composition and productivity changes of the submerged vegetation of Lake Karakul, Pamir Mountains (Tajikistan), using sedimentary ancient DNA metabarcoding and elemental (C/N) and isotopic (δ13C, δ15N) measurements of Stuckenia cf. pamirica (Baagøe) Z. Kaplan (Potamogetonaceae) leaf remains. No Stuckenia cf. pamirica leaf remains were found for 28.7–26.1 cal ka BP, when both Potamogetonaceae and Chara (L.) DNA sequences were recorded, suggesting sparse submerged vegetation at the coring site. This agrees with the inference of a deep lake reached using geochemical proxies. From 26.1 to 17.5 cal ka BP a few macrophyte remains and high numbers of Potamogetonaceae sequences were recovered: lake level was probably low, as suggested by other studies on the lake. Another phase of increased numbers of Chara sequences and the absence of Stuckenia cf. pamirica leaf remains was found between 17.5 and 12.2 cal ka BP, which coincides with a lake-level transgression at Lake Karakul as indicated by paleo-shoreline investigations. Analyses of macrophyte remains reveal intermediate paleo-productivity from 6.9 cal ka BP and high paleo-productivity from 2.2 cal ka BP onwards. From comparisons with other studies, we suggest that lake-level changes are the main driver for the submerged vegetation composition and productivity at the coring site in Lake Karakul and underline our conclusions by depicting the present-day distribution of Stuckenia cf. pamirica and Chara within the lake.  相似文献   

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