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711.
712.
GIS与西部生态环境建设的有机结合将是一项长期的、复杂的系统工程。在严格论证了该项目实施的可行性之后,在可持续发展理论的指导下,运用空间分析方法,提出了项目的实施方案。在该方案中,对生态环境信息数据进行了分类,详述了空间数据文件存贮结构,查询管理子系统的开发,最后得出生态环境地理信息系统的总体结构,并简述了其功能。 相似文献
713.
Alternating nitrification-denitrification via nitrite for nitrogen removal from soybean wastewater by SBR with real-time control 总被引:3,自引:0,他引:3
A novel treating technology for nitrogen removal from soybean wastewater was studied. The process for nitrogen removal was achieved by alternating aeration and mixing, combined with real\|time control strategies. Results showed that the COD and total nitrogen removal rates are more than 90% and 92% at COD and total nitrogen loads of 1.0-1.2 kg COD/(kgMLSS·d) and 0.20-0.27 kg TN/(kgMLSS·d), respectively. In addition, it could improve sludge settling property. SVI value is less than 70 g/ml during the whole cycles. The method not only may be adapted to treat soybean wastewater with high nitrogen, but also may be applied to treat other high nitrogen wastewater. 相似文献
714.
水鸟是反映湿地生态系统健康的指标之一,对不同湿地水鸟多样性进行评价能提出有利于湿地生态系统健康良性发展的湿地管理措施,亦能更好地保护水鸟资源。为缓解近年来中国自然湿地退化和消失的问题,中国政府积极推进实施了大量修复自然湿地和新建人工湿地的工程。然而受限于人力、物力和经费,当前对自然湿地和人工湿地水鸟多样性的系统调查和评价多局限于单一地点或局部区域。因水鸟的分布具有地域性,从地域尺度进行不同湿地类型水鸟多样性评价将更为客观,公众科学数据为区域大尺度数据获取提供了可能。本研究借助中国观鸟记录中心数据,比较了2014年1月至2018年2月中国西南4省(市)自然湿地和人工湿地的水鸟物种多样性和组成相似性;结果共记录到9目19科139种水鸟,其中有94.96%的物种分布于自然湿地,67.63%的物种分布于人工湿地;各类群水鸟在自然湿地中的物种数均高于人工湿地。结果说明自然湿地在水鸟保护中具有重要栖息地功能,人工湿地能为大部分水鸟提供栖息地,但不能完全代替自然湿地。自然湿地中的湖泊湿地、河流湿地和沼泽化草甸以及人工湿地中的水库、城市人工景观水面和娱乐水面是水鸟,特别是受威胁水鸟分布的重要湿地类型;建议政府部门重点对上述湿地亚类进行合理的规划和管理。 相似文献
715.
我国北方沙尘暴与植被覆盖度关系研究 总被引:3,自引:0,他引:3
利用NOAA/AVHRR和旬归一化植被指数NDVI数据,计算了1983-2000年中国北方13省市区的植被覆盖度,分析了这些地区植被覆盖度的时间变化趋势和空间分布规律,研究了中国北方沙尘暴与植被覆盖度之间的关系。结果表明:我国北方沙尘灾害频次与植被覆盖度有很好的对应关系,1983-2000年的18年间,我国北方大部分地区植被覆盖度增加,这段时期沙尘灾害频次总体呈降低趋势,其中20世纪80年代我国北方大部分地区植被覆盖度增加,这一时期我国北方沙尘暴发生频数下降;20世纪90年代,我国北方大部分区域植被覆盖度呈下降趋势,特别是华北和西北干旱与半干旱地区,下降趋势显著,这一时期我国北方沙尘暴发生频数在减少中有回升趋势。研究结果表明,植被覆盖度是影响中国北方沙尘暴频次变化的重要因素。 相似文献
716.
717.
China is facing the challenge of many marine environment problems with rapid economic growth. Japan had experienced similar marine environmental pressure during its industrialization and had been facing the problem through successful environment policy step by step. The paper reviews the lessons and experiences of Japan’s marine environment protection and analyzes the marine environment pollution in China and its causes, taking Shandong province as a case, such as GDP-oriented economic growth, heavy coal assumption, etc. The paper also analyzes the marine industry with focuses on coastal tourism and its relationship with marine environment. Suggestions on polices are provided based on the analysis on China’ marine environment and Japan’s experience. 相似文献
718.
The voluntary emission reduction (VER) trading mechanism has played an important role in China’s seven pilot carbon markets. From a comprehensive review of the VER trading and offsetting mechanisms since 2013, this study analyses the quality management of the Chinese Certified Emission Reduction (CCER) in the pilot carbon markets, conducts a comparative analysis of the geographical and field distributions of proposed and registered projects and emission reductions and provides the CCER supply outlook for 2020 in the aspects of on record, project registration, emission reduction registration and emission reduction issuance. Results show that the potential number of CCER projects by 2020 will be 2,864, 1,047, 818, and 286 with the corresponding emission reductions amounting to 493, 212, 133, and 49 million tCO2e, respectively. Although considerable progress has been made, China remains confronted with many challenges in developing the VER trading system. Accordingly, policy stability and continuity and guarding against market risks should be maintained to enable the system to play a substantial role in promoting ecological progress and green low-carbon development in China. 相似文献
719.
As a carrier to develop various marine resources, sea area is regulated as a kind of important resources through legislation by many coastal countries with a management system for the paid use of sea area. Since the early 1990s, China has begun to implement the paid use and formed an institutional system comprised of three levels after developing it for more than two decades. From 2002 to 2015, the Chinese Government transferred the use right of sea area of 33,910 km2 by paid use and levied a total of 75.89 billion CNY (11.328 billion US dollars) of sea area use payment. Apart from this, the Government has gained rich experience in operating and managing the compensable use of sea area. After retrospectively analyzing the development history of paid use of China’s sea area, the research presents an institutional structure and the implementation of the management system for the paid use of sea area and the main problems therein. On this basis, management policies and feasible policy suggestions are proposed. Research results from this study can provide available references for other developing countries and emerging economies to apply and improve native management system for the paid use of sea area. 相似文献
720.
欧盟臭氧污染监测现状及我国开展臭氧污染监测的建议 总被引:1,自引:0,他引:1
张明顺 《环境监测管理与技术》2011,23(6):17-20
综述了欧盟臭氧前体物排放及地面臭氧污染监测的现状,分析了欧盟重视地面臭氧污染监测的原因及存在的主要问题.根据欧盟在地面臭氧污染监测方面的经验和做法,提出了加强我国地面臭氧污染监测的必要性和具体建议. 相似文献