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601.
东江干流东莞段水质研究   总被引:12,自引:0,他引:12  
东江是珠江水系的主要干流之一,是广东东部至关重要的水系,文中详细分析了东江东莞段90年代中后期的水质状况,在此基础上研究和探讨了东江东莞段水质的季节变化规律及其水质变化趋势。   相似文献   
602.
现代垃圾填埋技术设计理念及其工程应用   总被引:3,自引:1,他引:2  
对现代垃圾填埋技术的设计要点进行归纳,并结合上海市老港填埋场四期工程介绍其在工程设计中的具体应用。  相似文献   
603.
The social structure of animal aggregations may vary considerably in both space and time, yet little is known about how this affects vigilance. Here, we investigate the vigilance architecture of a colony of wild-living grey-headed flying-foxes (Pteropus poliocephalus) in Australia and examine how spatial as well as temporal variation in social organization influences social and environmental vigilance. We sampled color-marked individuals at different stages of the reproductive cycle and the year and at different locations in the colony to examine the effects of temporal and spatial factors on social and environmental vigilance. We found that vigilance architecture reflected the social structure of the colony, with the highest environmental vigilance being displayed by bats at the periphery of the colony, and the highest social vigilance by bats that roosted at intermediate distances from the colony’s edge. Furthermore, we found that vigilance levels reflected changes in reproductive state, with social vigilance increasing toward the mating season, particularly in males. Our findings show that spatial and temporal variation in social structure can have differential effects on social and environmental vigilance. This highlights the necessity to differentiate between functions of vigilance to understand fully vigilance architecture in aggregations of social animals.  相似文献   
604.
《大气污染防治法》授权国家环境保护主管部门制定大气污染物排放标准,但关于标准的法律规则还不够全面,在一定程度上影响了排放标准的功能发挥,也给标准限值确定带来了困难。当前国家正在对《大气污染防治法》进行修订,为完善相关标准条款,本文在对我国大气污染物排放标准立法现状分析的基础上,借鉴国外相关标准的立法规则和我国标准实践经验,提出了适用于我国的大气污染物排放标准制定的主要法律原则和程序建议。研究认为,制定大气污染物排放标准应考虑污染物对公众健康、空气质量和生态环境的影响,以及可采取的污染控制技术措施等情况,通过技术经济论证确定排放限值和相关技术要求,做到技术可行、经济合理、减排效益突出。标准制定过程要充分听取各方意见,经标准评审委员会审查通过后方可按照部门规章批准发布。  相似文献   
605.
付畅  吴方卫 《自然资源学报》2014,29(8):1430-1440
论文测算了我国能源作物和农林废弃物等原料的燃料乙醇转化潜力,发现2015-2030年我国燃料乙醇的理论生产能力将从6 364×104 t 增长到1.18×108 t,可行的产量水平将在1 387.9×104 t 以上。如果能实现这一产量,将在很大程度上缓解我国的石油供求矛盾。今后提高燃料乙醇生产能力的可行策略主要有以下方面:加强边际土地资源评估和开发,促进能源作物的规模化利用,通过利益引导加强秸秆能源化利用,延长林木采伐加工产业链,在农村地区发展沼气等新型能源替代薪柴。  相似文献   
606.
热带亚热带土壤氮素反硝化研究进展   总被引:4,自引:0,他引:4  
热带亚热带独特的土壤性质可能使得反硝化机理有别于温带土壤.文章综述了热带亚热带地区土壤氮素生物反硝化的研究进展,试图更好地了解该地区土壤反硝化在全球氮(N)循环以及在全球环境变化和生态系统响应互作中的角色.热带亚热带土壤反硝化强度普遍较温带地区弱,且随着土地利用方式和耕作管理措施的不同而呈现较大的时空变异性.影响土壤水分状况和土壤碳(C)、N 转化特性和速率的因素即为区域和农田尺度上的反硝化影响因素.湿润型热带亚热带土壤由于含有丰富的氧化物而致使土壤氧化还原势较高,这也是导致该地区土壤反硝化势较温带地区较低的关键土壤因素之-.然而土壤pH 值不是该地区土壤反硝化势较低的主要限制因素.有机C 矿化过程较土壤全氮含量和土壤C/N 比在决定湿润型亚热带土壤反硝化势方面更为重要.愈来愈多的证据表明热带亚热带土壤反硝化的生态环境效应不同于温带地区,热带亚热带地区土壤反硝化对全球变暖的贡献应综合考虑其对其它温室气体(如CH4,CO2)排放和氮沉降的影响.热带亚热带土壤生态系统具有-些防止土壤氮素反硝化损失的机制和保氮策略.然而,热带亚热带生态系统对全球变化的响应机制及其生物地球化学调控机制仍然不清楚,这些研究对于反硝化和其它同时发生的氮转化过程模型的精确构建至关重要.  相似文献   
607.
Few studies have explored the relationships between nation‐building, disaster risk reduction and climate change adaptation. Focusing on small island developing states, this paper examines nation‐building in Timor‐Leste, a small island developing state that recently achieved independence. Nation‐building in Timor‐Leste is explored in the context of disaster risk reduction, which necessarily includes climate change adaptation. The study presents a synopsis of Timor‐Leste's history and its nation‐building efforts as well as an overview of the state of knowledge of disaster risk reduction including climate change adaptation. It also offers an analysis of significant gaps and challenges in terms of vertical and horizontal governance, large donor presence, data availability and the integration of disaster risk reduction and climate change adaptation for nation‐building in Timor‐Leste. Relevant and applicable lessons are provided from other small island developing states to assist Timor‐Leste in identifying its own trajectory out of underdevelopment while it builds on existing strengths.  相似文献   
608.
In response to the pressing global challenges of climate change, initiatives under the auspices of ‘reducing emissions from deforestation and forest degradation’ (REDD) have been implemented in over 30 developing and least-developed countries since 2005. The initiatives cover nearly every significant and vulnerable forest ecosystem worldwide. In this study we review six representative initiatives, two each from Africa, Asia and Latin America. Strength, weakness, opportunity and threat analysis is done to evaluate each initiative's policy framework, design, implementation and results thus far. The main policy and project implementation factors that appear to lead to effective and successful REDD project outcomes include having clearly formulated project design; governance, land tenure rights and capacity; equity and transparency; indigenous peoples' rights and knowledge; local–international coordination; and enhancing local and institutional capacities. Based on these findings, we provide recommendations for future REDD policy action and project implementation to make it work for the poor and achieve its intended goals.  相似文献   
609.
Populations affected by violent conflicts often withstand threats to their security as well as threats to their livelihoods. Their response to the former threats nontrivially affects their response to the latter threats, and vice versa. This paper examines the interplay between protection and livelihood strategies using a sample of households selected from the Anuradhapura district of Sri Lanka. The fieldwork for this study was completed in 2008, producing evidence that the protection and livelihood strategies employed by households affected by the protracted conflict in Sri Lanka are interlaced. In addition, the research discovered that Muslim and Sinhalese households largely responded to the protracted conflict in ways that are unique to their ethnic group. Certain vulnerabilities that impinge on protection and certain opportunities that support livelihoods are shown to be ethnicised. Hence, the final livelihood outcome, which is defined narrowly here as the household's income, also appears to be ethnicised.  相似文献   
610.
《Environmental Hazards》2013,12(4):267-280
The present perspective summarizes and projects the results of a two-day workshop held in 2013 with the presence of 21 known disaster risk specialists from academia and practice. Faced with the disconnect between ever-increasing and even-accelerating disaster losses and the declared progress in disaster risk management (DRM) practice over the last eight years, the document attempts to explain the current situation and project future needs in order to increase the saliency and effect of DRM. A review of current conceptual problems and their impact on knowledge and action, of the current role of DRM in society, of governance aspects and of the notion of transformative development and its relationship to DRM is provided. The critique of current practice and understanding of disaster risk then leads to an attempt to identify key needs for the future and changes that must be introduced in order for DRM to become more mainstream and effective. Among the more central concerns, the document points to the way in which disasters are still many times seen as exogenous happenings as opposed to social constructions, product of skewed development practices. This then is reflected in much governance practice and action that are flawed. The difficulty in moving from a reactive and corrective DRM practice to a more prospective, risk avoidance practice is also highlighted.  相似文献   
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