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31.
Small-scale fisheries are important in Laos, where rural people heavily depend upon Mekong River and tributary fish stocks for their livelihoods. Increasing pressures from human exploitation and habitat disturbance, however, have raised serious concerns about the potential depletion of various species. This has led to the establishment of large numbers of Fish Conservation Zones (FCZs) or “no-take” fish sanctuaries in southern Laos based on a “community-based fisheries co-management” framework. This study uses the local ecological knowledge (LEK) of fishers to assess the effectiveness of village-managed FCZs in enhancing fish stocks in the mainstream Mekong River in Khong District, Champasak Province. Focus group interviews about species that are believed to have benefited from different FCZs are compared with parameters such as FCZ area, age, depth, localized gradient, water velocity, and the presence of wetland forests nearby. The results suggest that no one aspect is likely to account for variations in fish stocks; rather, it is the interaction between numerous factors that has the largest impact. Secondly, the results indicate that microhabitat diversity and protection are critical for maintaining and enhancing Mekong fisheries. Deep-water pools are particularly important as dry season refuges for many fish species, and FCZ depth may be the single most important environmental factor affecting the success of FCZs in the Mekong River. FCZs have the most potential to benefit relatively sedentary species, but may also benefit highly migratory species, given the right conditions. This study shows that integrated approaches to stock assessment that employ LEK and scientific fisheries management have considerable potential for improving Mekong capture-fisheries management.  相似文献   
32.
目的 掌握东南亚地区环境特征,提出产品环境适应性工作对策。方法 采用主成分分析法开展东南亚地区环境精细化分类,依据分类结果,开展环境特征分析和规律研究,并在产品环境适应性问题原因分析的基础上,提出东南亚地区使用产品环境适应性工作对策。结果 东南亚地区具有年温度较高、相对湿度高、雨量充沛、太阳辐射较强等特征,但不同类别之间具有一定的差异性,D1、D2类环境呈现一定的季节性特征,D3、D4类全年环境较为稳定,温度、平均湿度、太阳辐射和降雨量均稳定地保持在较高量值范围内,温度常年保持在20~30℃,平均相对湿度在70%以上。结论 东南亚地区环境整体较为严酷,在产品环境适应性论证、设计和使用维护等阶段应采取针对性措施,以保证东南亚地区使用产品的环境适应性。  相似文献   
33.
The thawing and subsequent decomposition of large stocks of soil organic carbon (SOC) currently stored in the northern circumpolar permafrost region are projected to result in a ‘positive’ feedback on global warming. The magnitude of this feedback can only be assessed with improved knowledge about the total size and geographic distribution of the permafrost SOC pool. This study investigates SOC storage in an under-sampled mountain permafrost area in the Russian High Altai. SOC stocks from 39 soil pits are upscaled using a GIS-based land cover classification. We found that the top 100 cm of soils in Aktru Valley and the adjacent Kuray Basin only holds on average 2.6 ± 0.6 kg C m−2 (95% confidence interval), of which only c. 1% is stored in permafrost. Global warming will result in an upward shift of alpine life zones, with new plant cover and soil development at higher elevations. As a result, this type of mountain permafrost area might act as a net C sink in the future, representing a ‘negative’ feedback on global warming.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01433-6) contains supplementary material, which is available to authorized users.  相似文献   
34.
Water security: Old concepts,new package,what value?   总被引:1,自引:0,他引:1  
“Water security” has come to infiltrate prominent discourse in the international water and development community, and achieving it is often viewed as a new water sector target. Despite the elevated status that the concept has increasingly acquired, understandings of the term are murky and quantification is rare. To promote a more tangible understanding of the concept, this paper develops an index for evaluating water security at a country level. The index is comprised of indicators in five components considered to be critical to the concept: (i) basic needs; (ii) agricultural production; (iii) the environment; (iv) risk management; and (v) independence. Achieving water security in these components can be considered necessary but insufficient criteria to measure the achievement of security in related areas such as health, livelihoods, and industry. After populating indicators with data from Asia‐Pacific countries, results are interpreted and the viability of methods is discussed. This effort comprises an important first step for quantifying and assessing water security across countries, which should spur more concrete understanding of the term and discussion of its added value.  相似文献   
35.
Water Resources of Central Asia and Adaptation Measures for Climate Change   总被引:1,自引:0,他引:1  
A large part of the Central Asian region is located within the inner flow of the Aral Sea basin. The water resources are formed from renewed superficial and underground waters of natural origin, and also with returnable waters. The intensive increase of water intake, that took place in the second half of the twentieth century caused practically complete assimilation of the river inflow. That was the main reason for the Aral Sea crisis. On the basis of the analysis of long periodical rows of observation by meterological and hydrological stations, the estimation of regional water resources and calculations of changes of some components of the hydrological cycle due to the expected climate changes are presented. Measures for adaptation in the southern part of the Aral Sea region are considered.  相似文献   
36.
Fujii Y  Yan J  Harada KH  Hitomi T  Yang H  Wang P  Koizumi A 《Chemosphere》2012,86(3):315-321
In this study, 90 human breast milk samples collected from Japan, Korea, and China were analyzed for perfluorooctanoic acid (PFOA) (C8), perfluorononanoic acid (PFNA) (C9), perfluorodecanoic acid (PFDA) (C10), perfluoroundecanoic acid (PFUnDA) (C11), perfluorododecanoic acid (PFDoDA) (C12), and perfluorotridecanoic acid (PFTrDA) (C13). In addition, infant formulas (n = 9) obtained from retail stores in China and Japan were analyzed. PFOA was the predominant compound and was detected in more than 60% of samples in all three countries. The PFOA, PFNA, PFDA, and PFUnDA levels in Japan were significantly higher than those in Korea and China (p < 0.05). The PFTrDA level was highest in Korea (p < 0.05). The median PFOA concentrations were 89 pg mL−1 (48% of total perfluorinated carboxylic acids (PFCAs) (C8-C13)) in Japan, 62 pg mL−1 (54%) in Korea, and 51 pg mL−1 (61%) in China. The remaining ∑PFCAs (C9-C13) were 95 pg mL−1 in Japan, 52 pg mL−1 in Korea, and 33 pg mL−1 in China. Among the long-chain PFCAs, odd-numbered PFCAs were more frequently detected than even-numbered PFCAs, except for PFDA in Japan. There were no evident correlations between the mother’s demographic factors and the PFCA concentrations. PFOA, PFNA, and PFDA were frequently detected in both Japan and China, but there were no significant differences between the two countries. The total PFCA concentrations in the infant formulas were lower than those in the breast milk samples in Japan (p < 0.05), but not in China (p > 0.05). In conclusion, various PFCAs were detected in human breast milk samples from East Asian countries.  相似文献   
37.
In order to better understand the behavior of 210Pb deposition in Far East Asia, comprehensive data of monthly 210Pb deposition, which includes several time-series and spatial distribution data at 14 stations in Japan and 2 stations in Taiwan, were analyzed. Pb-210 deposition at most of the sites exhibited a typical seasonal change with higher values in winter and lower values in summer; especially, the greatest 210Pb deposition in the world occurred in winter at sites beside the Japan Sea. The deposition behavior of 210Pb in Far East Asia differed between winter and summer. The meteorological phenomenon peculiar to winter of the Japan Sea side, i.e., formation of the Japan Sea convergence zone, might cause the high 210Pb concentration in rainwater, as may heavy snowfall. The 210Pb concentration in rainwater showed long-term variability, although this differed between winter and summer. This long-term variability may be related to climatological factors such as El Niño.  相似文献   
38.

Introduction

Fatalities from traffic accidents in less-motorized societies are an important global issue. We aimed to characterize the geographic differences of fatalities in such societies to facilitate the development of targeted interventions.

Method

This study linked police reports, hospital data, and vital registration data from Taiwan with special reference to accident factors in pre-hospital deaths and medical care in hospital deaths.

Results

A higher percentage of pre-hospital deaths were observed following rural as compared to urban traffic accidents. The deaths due to rural accidents can be attributed to lower use of restraints (i.e., helmets or seat belts), lower percentage of motorcyclists, and more highway accidents. A higher percentage of victims in rural accidents were transported to distant medical centers rather than to local hospitals.

Conclusion

Specific interventions, such as intelligent emergency medical systems, campaigns for helmets and seat belt usage, enforcement of helmets and seat belt use, and speed control measures should be targeted to rural areas.

Impact on industry

Cooperation between the vehicle industry and emergency medical providers in rural traffic accident rescue teams may decrease the numbers of deaths in these regions.  相似文献   
39.
The contemporary Asian silver cycle: 1-year stocks and flows   总被引:2,自引:0,他引:2  
The stocks and flows of silver throughout the Asian economy for 1997 have been quantified, with major flows examined over their entire life cycle, including mining, production, fabrication, and manufacture, product use, and waste management. By compiling the findings of 11 country-level material flow analyses, a regional analysis was created. The reliability and availability of the data varied, with the most confidence given to the earlier life stages and the most uncertainty existing later. Overall, Asia is a net importer of silver, requiring nearly 7000 Mg of silver in 1997. Approximately 2200 Mg Ag are mined, and production waste totals about 640 Mg Ag. The flow of silver into use equals 9900 Mg Ag, with a considerable build-up of 7100 Mg Ag entering in-use stock. Silver waste sent directly to the environment, in addition to landfilled waste, totals 1600 Mg Ag. Much variation exists when examining country-level silver flows on a per capita basis. India and Thailand’s fondness for silver jewelry greatly increases their silver flows into use and in-use stock. Japan’s high overall consumption reflects its high GDP per capita. Regionally, a significant potential exists to tap the silver contained in the in-use stocks and to enhance the recycling rates.  相似文献   
40.
Sustaining Asia's groundwater boom: An overview of issues and evidence   总被引:6,自引:0,他引:6  
This article suggests that Asia’s groundwater socio‐ecology is at an impasse. Rapid growth in groundwater irrigation in South Asia and the North China plains during the period 1970–95 has been the main driver of the agrarian boom in these regions. India, Pakistan, Bangladesh and China account for the bulk of the world’s use of groundwater in agriculture. On the plus side, groundwater development has provided sustenance to agrarian economies and millions of rural livelihoods. On the downside, it has created chronic problems of resource depletion and quality deterioration. While problems of groundwater depletion, pollution and quality deterioration are indeed serious, so are the consequences of the degradation of the resource for those that have come to precariously depend upon groundwater irrigation. Three problems currently afflict groundwater use: depletion due to overdraft; water logging and salinization; and pollution due to agricultural, industrial and other human activity. The pathology of the decline in groundwater socio‐ecology reflects a remarkably similar pattern across regions. The critical issue for Asia now is: what might be done to sustain and revive these groundwater socio‐ecologies vital to the region’s economy? This article reviews a variety of techno‐institutional approaches. However, transposing lessons from the industrialized world uncritically in the Asian context may not work. A more nuanced understanding of the peculiarities of Asia’s groundwater socio‐ecology is needed.  相似文献   
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