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101.
云南地区种子植物东亚分布成分的地理分布格局   总被引:2,自引:0,他引:2  
植物区系分析是理解植被起源、性质和分布的基础.本研究利用大尺度的区系分布信息,结合地理信息系统平台和统计分析方法,探讨了云南地区种子植物东亚分布成分的地理分布格局以及\"田中线\"的生物地理意义.结果表明,东亚分布成分及其亚型所占比重均随着纬度的升高呈递增趋势.在经度梯度上,中国-日本植物分布亚型所占的比重从东到西呈递减趋势,而中国-喜马拉雅分布亚型所占比重的经度格局则与此相反.东亚分布成分在云南地区的扩散方向以由北到南为主,其次为经度梯度上的双向迁移.与过去的研究不同,本研究结果表明,东亚分布成分在云南地区的起源中心更可能为滇西北.我们未能证实\"田中线\"对中国-喜马拉雅分布亚型的分布具有限制意义,但对东亚分布成分(总体)和中国-日本分布亚型在云南地区的分布具有严格的限制意义.  相似文献   
102.
Political Incentives for Biodiversity Conservation   总被引:2,自引:0,他引:2  
Abstract:  There seems to be a worldwide lack of political will for conservation that leads, inevitably, to an undermining of conservation policy. This is a standard complaint but one that has received little academic attention. In an attempt to better understand the gap between conservation policy and practice, we examined conservation policies and practice as they have played out in the Great Himalayan National Park, Himachal Pradesh, India, over the past two decades. In particular we consider the park's experience within two larger contexts: (1) Himachal's current development orientation, which seeks to transform the state into the electrical powerhouse of the country by building over 300 medium and large power projects and (2) electoral politics that result in politician's support for villagers and others denied access to national parks and wildlife sanctuaries. Each of these factors works to undermine state conservation policies. Conservationists need to build political bridges with local communities if they are to use electoral power to work for rather than against conservation. Only such electoral power can be expected to force governments to adopt more cautious policies in advancing a particular development agenda. In the absence of strategic alignments in places such as Himachal Pradesh with strong democratic traditions, one must expect continued political support for potentially destructive megaprojects and an absence of political support for the conservation of biological diversity.  相似文献   
103.
    
Poverty, unemployment, and environmental degradation are growing issues and significant challenges to sustainable development. They are visible obstacles to achieving the United Nations Sustainable Development Goals (SDGs). The three ZEROS (zero net carbon emissions, zero poverty, and zero unemployment) within the SDGs have not yet been thoroughly explored and need to be empirically examined. This is the primary aim of this study, which focuses on 10 developing countries in Asia & the Pacific. The study utilized panel data from 1997 to 2021 and a stochastic impact by regression on population, affluence, and technology (STIRPAT) model and implemented the second-generation panel unit root test, cross-sectional augmented autoregressive distributed lags (CS-ARDL), panel fully modified ordinary least squares (FMOLS) approaches, and panel Granger-causality test. The empirical results of the CS-ARDL approach vindicate that poverty contributes to the environmental deterioration proxied by CO2 emissions, while the unemployment rate inhibits the environmental damage. The other regressors, namely national income by real gross domestic product per capita, energy use, and population are harming the environment, while technological innovation and digitalization reduce environmental degradation. These results are re-corroborated by implementing the FMOLS estimator. The Granger causality results reveal a bidirectional causality between poverty and environmental degradation. Therefore, it is essential for management authorities to implement pragmatic public policies that focus on sustainable development strategies, such as investing in education and stimulating sustainable economic growth. This will help to reduce unemployment, improve living standards, decrease poverty, and ultimately achieve the Three Zeros Club initiative and sustainable development goals.  相似文献   
104.
    
The study aims to examine lagged causal effect of economic development policies on the carbon footprint of Southeast Asia. This study employs unit root test, cointegration test and panel data analysis methods to examine endogeneity concerns in observational data. The study applies panel data analysis methods to address unobserved country effect in the model. The balanced panel data includes a total of 240 observations with five cross sections of five nations in Southeast Asia and with 48 time-specific periods of 1970–2017. The results indicate that (1) exports, industrialization, urbanization and economic growth have lagged negative effect on the carbon footprint of the region in the short-run, and (2) there exists a long-run equilibrium relationship among exports, industrialization, urbanization, economic growth and carbon footprint in the region. The findings suggest that the economic growth, exports, industrialization and urbanization of the developing countries in Southeast Asia have been achieved at the cost of increasing the carbon footprint of the region. The findings imply that the environmental policy of the export-led growth countries never have been effective so far since the nations have achieved their economic growth at the high cost of harming the environment of the nations.  相似文献   
105.
The shark fin trade is a major driver of shark exploitation in fisheries all over the world, most of which are not managed on a species‐specific basis. Species‐specific trade information highlights taxa of particular concern and can be used to assess the efficacy of management measures and anticipate emerging threats. The species composition of the Hong Kong Special Administrative Region of China, one of the world's largest fin trading hubs, was partially assessed in 1999–2001. We randomly selected and genetically identified fin trimmings (n = 4800), produced during fin processing, from the retail market of Hong Kong in 2014–2015 to assess contemporary species composition of the fin trade. We used nonparametric species estimators to determine that at least 76 species of sharks, batoids, and chimaeras supplied the fin trade and a Bayesian model to determine their relative proportion in the market. The diversity of traded species suggests species substitution could mask depletion of vulnerable species; one‐third of identified species are threatened with extinction. The Bayesian model suggested that 8 species each comprised >1% of the fin trimmings (34.1–64.2% for blue [Prionace glauca], 0.2–1.2% for bull [Carcharhinus leucas] and shortfin mako [Isurus oxyrinchus]); thus, trade was skewed to a few globally distributed species. Several other coastal sharks, batoids, and chimaeras are in the trade but poorly managed. Fewer than 10 of the species we modeled have sustainably managed fisheries anywhere in their range, and the most common species in trade, the blue shark, was not among them. Our study and approach serve as a baseline to track changes in composition of species in the fin trade over time to better understand patterns of exploitation and assess the effects of emerging management actions for these animals.  相似文献   
106.
Abstract:  Limestone (karst) outcrops in Southeast Asia are rich in land snails. Certain groups of land snails, in particular Prosobranchia species, are restricted to limestone and show a high degree of short-range endemism. Karst habitats are, however, seriously degraded by quarrying, logging, agriculture, and burning. The effect of these disturbances on land snail fauna is unknown, so we studied paired primary and secondary forest localities on six separate limestone hills in Sabah, Malaysian Borneo. Land snails were sampled with a standard protocol and identified to species level. More than 16,000 individuals, belonging to 74 species, were recorded. In most sites, snail diversities did not differ between disturbed and undisturbed plots. However, pulmonate snails were significantly more abundant at disturbed localities than prosobranch snails, whereas abundances for both groups were similar at undisturbed sites. Because Prosobranchia contain many site-endemic species, our findings suggest that continued exposure to these disturbances will eventually lead to extinctions in this group.  相似文献   
107.
针对规划环境影响评价所面临的关键问题之一,即规划布局的优化调整问题,以海南博鳌亚洲论坛特别规划区为研究对象,综合考虑该地区的功能定位及其生态环境特征,筛选出具有代表性的生态适宜性评价因子和生态敏感性评价因子,利用地理信息系统空间分析工具对该地区生态适宜性和敏感性进行评价。根据生态适宜性与敏感性评价结果,进行案例区主体功能区划分。在此基础上,通过比较主体功能区划与案例规划布局,从建设用地地块层面提出具体的规划布局优化调整建议。研究结果表明:规划的141个建设用地地块中,约四成位于禁止开发区和限制开发区,建议控制项目规模或者取消项目。通过基于主体功能区划的规划布局优化调整方法及其案例研究,从环境保护与生态建设角度指导该地区规划布局,同时也丰富和发展了规划环境影响评价技术方法。  相似文献   
108.
Land-Use and Land-Cover Change in Montane Mainland Southeast Asia   总被引:12,自引:1,他引:12  
This paper summarizes land-cover and land-use change at eight sites in Thailand, Yunnan (China), Vietnam, Cambodia, and Laos over the last 50 years. Project methodology included incorporating information collected from a combination of semiformal, key informant, and formal household interviews with the development of spatial databases based on aerial photographs, satellite images, topographic maps, and GPS data. Results suggest that land use (e.g. swidden cultivation) and land cover (e.g. secondary vegetation) have remained stable and the minor amount of land-use change that has occurred has been a change from swidden to monocultural cash crops. Results suggest that two forces will increasingly determine land-use systems in this region. First, national land tenure policies—the nationalization of forest lands and efforts to increase control over upland resources by central governments—will provide a push factor making it increasingly difficult for farmers to maintain their traditional swidden land-use practices. Second, market pressures—the commercialization of subsistence resources and the substitution of commercial crops for subsistence crops—will provide a pull factor encouraging farmers to engage in new and different forms of commercial agriculture. These results appear to be robust as they come from eight studies conducted over the last decade. But important questions remain in terms of what research protocols are needed, if any, when linking social science data with remotely sensed data for understanding human-environment interactions.  相似文献   
109.
    
Shana Scogin; 《Disasters》2024,48(1):e12596
How does male out-migration impact women's experience of post-disaster reconstruction? This paper employs survey data collected by Nepal's Housing Recovery Reconstruction Platform in 2018 to establish robust associations between male out-migration and three indicators of women's participation in rebuilding their private houses after the 2015 Gorkha earthquake: (i) knowing where to consult for information; (ii) visiting a local government official by oneself; and (iii) signing a rebuilding agreement with the local government. Twenty-six semi-structured interviews conducted in 2022 further revealed that women whose husbands were abroad undertook roles that they would not have performed had their spouse been present, including in relation to management and decision-making. However, the interviews also highlighted challenges that women had to overcome, such as a lack of knowledge of procuring materials and difficulties leading the process as a woman. This study advances the literature by establishing a relationship between male out-migration and variation in women's post-earthquake rebuilding experiences.  相似文献   
110.
    
The official environmental discourse in Laos describes a “chain of degradation” stretching from upland shifting cultivation, increased runoff and soil erosion to the siltation of wetlands and reservoirs. This perspective has had wide‐ranging impacts on rural development policy which, in the uplands, has long favoured forest conservation over agriculture. Integrating soil erosion and water sediment data with local perceptions of land degradation in an upland village of northern Laos, this study tests the validity of the official environmental discourse. Biophysical measurements made in a small agricultural catchment indicate a significant correlation between the spatial extent of cultivation and soil erosion rates. However, sediment yields recorded at the outlet of the catchment highlight relatively low levels of off‐site sediment exportation. Furthermore, farmers' perceptions suggest that local land degradation issues and crop yield declines could be less related to soil erosion than to agricultural land shortage, increased weed competition, and fertility losses resulting from the intensification of shifting cultivation. The study concludes that a better understanding and management of land degradation issues can be achieved by developing more inclusive and scientifically‐informed approaches to environmental perceptions and narratives.  相似文献   
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