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101.
In this study we used high resolution (20 m) land cover maps to derive detailed information on land cover structure within the classes of a regional medium resolution (500 m) land cover map. This enabled improved biomass estimation for the medium resolution land cover classes. Although our results suggested that land cover maps based merely on medium resolution remote sensing data can be used to monitor the extent of forest cover, they also showed that these maps alone are not sufficient to produce reliable regional estimates on above ground biomass in insular Southeast Asia. A quarter of the study area was covered by sub-pixel size (500 m) mosaic of various land cover types containing 14% of biomass. In total, non-forest areas covered over 60% of the study area and included 43% of biomass. In these areas, highly fragmented within class land cover structure was shown to significantly affect biomass estimates. Therefore we conclude that forest/land cover monitoring based merely on medium resolution remote sensing data can no longer be used to sufficiently quantify carbon fluxes connected to land cover changes in insular Southeast Asia, but multi-resolution approaches are needed to perform this task.  相似文献   
102.
Prior to independence, Central Asian countries were closely interconnected through the regional management incorporating water, energy, and food sectors. This approach, supported by the central government of Union of Soviet Socialist Republics (USSR), functioned effectively — meeting the needs of both upstream and downstream countries. However, after independence, Central Asian countries started prioritizing their own economic development policies without due account to regional concerns such as joint use of water resources, leading to instability. In this study, the case of Syrdarya basin was investigated to show how such strategies create tension in the region, since primary focus is given to national interests, without consideration for regional problems. To address this issue, an integrated approach to incorporating water, energy, and agriculture is needed. It is suggested that a single sector approach on water alone does not lead to stability, and a multi-sectoral approach is necessary to ensure sustainable development. Countries sharing benefits from the river have to be responsible for costs of operation and maintenance of the water facilities.  相似文献   
103.
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   
104.
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   
105.
We examined the links between the science and policy of habitat corridors to better understand how corridors can be implemented effectively. As a case study, we focused on a suite of landscape‐scale connectivity plans in tropical and subtropical Asia (Malaysia, Singapore, and Bhutan). The process of corridor designation may be more efficient if the scientific determination of optimal corridor locations and arrangement is synchronized in time with political buy‐in and establishment of policies to create corridors. Land tenure and the intactness of existing habitat in the region are also important to consider because optimal connectivity strategies may be very different if there are few, versus many, political jurisdictions (including commercial and traditional land tenures) and intact versus degraded habitat between patches. Novel financing mechanisms for corridors include bed taxes, payments for ecosystem services, and strategic forest certifications. Gaps in knowledge of effective corridor design include an understanding of how corridors, particularly those managed by local communities, can be protected from degradation and unsustainable hunting. There is a critical need for quantitative, data‐driven models that can be used to prioritize potential corridors or multicorridor networks based on their relative contributions to long‐term metacommunity persistence.  相似文献   
106.
Tai Lake (Ch: Taihu) has attracted international attention forcyanobacteria blooms. However, the drivers of cultural eutrophication, especially long-term socio-economic indicators have been little researched. The results of research demonstrate how socio-economic development affected quality of water and how it has been improved by anthropogenic activities. This study described variability in indicators of water quality in Tai Lakeand investigated thedrivers. Significant relationships existed between concentrations of annual mean total nitrogen (TN), total phosphorous (TP), chemical oxygen demand (COD) and biological oxygen demand (BOD), and population, per capital gross domestic production (GDP) and sewage discharge (p?<?0.05). However, mechanisms causing change varied among TN, TP, COD and BOD. Before 2000, the main contributors to increases in concentrations of TN were human population, GDP and volumes of domestic sewage discharges. After 2000, discharges of industrial sewage become the primary contributor. After 1998, the regressions of annual mean TN, TP and COD on per capital GDP, population and domestic sewage discharge were reversed compared to the former period. Since 1999, an apparent inverted U-shaped relationship between environmental pollution and economic development has developed, which indicated that actions taken by governments have markedly improved quality of water in Tai Lake. The statistical relationship between BOD and per capital GDP didn’t conform to the Kuznet curve. The U-shaped Kuznet curve may offer hope for the future that with significant environmental investments a high GDP can be reached and maintained without degradation of the environment, especially through appropriate management of industrial sewage discharge.  相似文献   
107.
索尔库里盆地位于青藏高原东北缘,柴达木盆地的北部,气候恶劣、交通不便,研究资料匮乏。通过对索尔库里北盆地彩虹沟剖面新近纪中后期沉积物的古地磁测年和碳酸盐碳氧同位素质谱分析,揭示了索尔库里盆地13.5~2.5 Ma长序列气候演变过程。13.5~9.2 Ma时期相对冷干,9.2~5.3 Ma时期相对温湿,5.3~3.9 Ma时期相对暖湿,3.9~2.5 Ma时期再次转为冷干。11 Ma左右,青藏高原东北缘隆升到阻止印度洋暖湿气流向北方运输的高度,地处走滑盆地的索尔库里地区逐渐变得极其干旱,标志着亚洲内陆干旱化在此背景下开始。红粘土磁化率和碳氧同位素变化等证据显示,西风在本区贯穿始终,而季风的出现加剧了亚洲内陆古气候的干湿更迭,对区域及全球古气候重建具有重要意义。  相似文献   
108.
东亚地区硫污染物的空间分布特征   总被引:4,自引:0,他引:4  
利用一个硫沉降模式分析了东亚地区SO2和SO42-浓度的空间分布及其特征.不同天气条件下,SO2和SO42-的浓度不同,高层SO2和SO42-的浓度分别为04—10μg/m3和02—05μg/m3;中层为40—100μg/m3和20—60μg/m3;近地层为40—300μg/m3和20—80μg/m3.分析表明,近地面浓度分布受源的影响比较明显,高层的浓度分布与湿清除过程密切相关,其浓度的低值区与降水区和云区有较好的对应.中层浓度分布体现了源、中层气流及湿清除的共同作用.  相似文献   
109.
海洋环境管理对于保护和保全海洋环境、推动海洋经济发展、构建生态文明具有重要意义。由于不同国家和地区的政治、经济、海洋战略和文化背景的差异,海洋环境管理的实施没有一个统一的标准模式,所解决的重点问题也不一样。这种多样性使得目前还没有一套通用的海洋环境管理评价体系。为此,本文以东北亚沿海各国为例,借鉴已有研究,从机构设置、法律体系和海洋环境状况三个方面出发,构建了包含定性和定量指标的海洋环境管理效果评价指标体系,在此基础上对东北亚沿海各国海洋环境管理效果进行定量评价与对比分析。结果表明,在机构设置和法律体系方面,日本领先于其他国家;在海洋环境管理方面,朝鲜较优;综合各方面后,日本表现最优,韩国、中国次之,朝鲜、俄罗斯较差。本研究提出的评价方法,可以较为客观地反映不同政治、经济和文化背景下国家在海洋环境管理方面的努力,可为我国审视自身不足、立足国情构建我国特色的海洋环境管理体制提供重要的方法指导和实践经验。  相似文献   
110.
This article reviews water-related urban environmental conditions in Southeast Asia. It argues that the development of urban environmental challenges in the region follows a unique pattern compared with those experienced in the now developed world. The new pattern is defined by the so called time–space telescoping of the development process. The process of time–space telescoping reduces the levels of income at which environmental challenges emerge and forces their appearance in a simultaneous fashion, as sets of problems. During previous eras, cities experienced sequential environmental transitions. Urban water-related environmental burdens emerged on local scales and expanded geographically and temporally in impact, with growing levels of affluence. Moreover, certain environmental challenges appeared later in economic growth because the technologies and practices that induced these problems emerged at higher levels of income. The article has two main findings. First, except for wealthy urban centers, for example Singapore, cities in the region are experiencing multi-scaled water burdens simultaneously. Second, low-income and middle-income cities are experiencing burdens at lower levels of income than did their contemporaries in the north.
Peter J. MarcotullioEmail:
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