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31.
在分析兴都库什-喜马拉雅地区生物资源和生物贸易特点基础上,本文就《国际生物多样性公约》框架下的《名古屋议定书》在本地区实施的主要机遇和挑战进行了分析。研究认为,本地区各国在具体执行议定书时面临的困难依然严峻,应该不断在议定书的法律框架下规范遗传资源以及相关传统知识的贸易、使用与共享机制。同时,不断完善法律体系建设,提高全民资源保护意识、建立良好信用制度,提高遗传资源获取和鉴定的科学技术水平。  相似文献   
32.
本文简要介绍了JAVA数据库互联(JDBC)技术,以一个实例程序讲解JDBC技术实现和 相关配置的操作步骤。  相似文献   
33.
黑岱沟露天煤矿排土场果园景观生态建设研究   总被引:2,自引:0,他引:2  
本文通过对黑岱沟露天煤矿开发所形成新的人工环境条件下的气候和土壤等因子分析,应用景观生态学原理,规划建设了以观赏为主的果园观生态建设。通过对所载植果树和其它乔灌木的观测研究,筛选出了适宜于排土场生长的杏树、苹果梨、123苹果、山桃等果树品种,以及油松、旱柳、榆树、沙棘、玫瑰和先辈乔灌木品种,完成了排土场的景观生态建设工作,为矿区大面积土地复垦提供了依据。  相似文献   
34.
Assessment of yield losses in tropical wheat using open top chambers   总被引:2,自引:0,他引:2  
The present study deals with the evaluation of effects of ambient gaseous air pollution on wheat (Triticum aestivum L. var. HUW-234) growing in a suburban area situated in eastern Gangetic plain of India, using open top chambers. Eight hourly air monitoring was conducted for ambient concentrations of SO2, NO2 and O3 in filtered chambers (FCs), non-filtered chambers (NFCs) and open plots (OPs). Various morphological, physiological and biochemical parameters were assessed during different developmental stages and finally yield parameters were quantified at the time of harvest.Mean concentrations of SO2, NO2 and O3 were 8.4, 39.9 and 40.1 ppb, respectively during the experiment in NFCs. Concentrations of SO2, NO2 and O3 reduced by 74.6%, 84.7% and 90.4%, respectively in FCs as compared to NFCs. Plants grown in FCs showed higher photosynthetic rate, stomatal conductance, chlorophyll content and Fv/Fm ratio as compared to the plants in NFCs and OPs. Lipid peroxidation, proline, total phenol and ascorbic acid contents and peroxidase activity were higher in plants grown in NFCs. There were improvements in morphological parameters of plants growing in FCs as compared to those in NFCs and OPs. Yield of plants also increased significantly in FCs as compared to those ventilated with ambient air (NFCs) or grown in OPs. During the vegetative phase, NO2 concentrations were higher than O3, but O3 became dominant pollutant during the time of grain setting and filling. The study concludes that O3 and NO2 are the main air pollutants in the sub-urban areas causing significant yield reductions in tropical wheat plants.  相似文献   
35.
Black carbon (BC) has importance regarding aerosol composition, radiative balance, and human exposure. This study adopted a backward-trajectory approach to quantify the origins of BC from anthropogenic emissions (BCAn) and open biomass burning (BCBB) transported to Xishuangbanna in 2017. Haze months, between haze and clean months, and clean months in Xishuangbanna were defined according to daily PM2.5 concentrations of >75, 35–75, and <35 µg/m3, respectively. Results showed that the transport efficiency density (TED) of BC transported to Xishuangbanna was controlled by the prevailing winds in different seasons. The yearly contributions to the effective emission intensity of BCAn and BCBB transported to Xishuangbanna were 52% and 48%, respectively. However, when haze occurred in Xishuangbanna, the average BCAn and BCBB contributions were 23% and 77%, respectively. This suggests that open biomass burning (BB) becomes the dominant source in haze months. Myanmar, India, and Laos were the dominant source regions of BC transported to Xishuangbanna during haze months, accounting for 59%, 18%, and 13% of the total, respectively. Furthermore, India was identified as the most important source regions of BCAn transported to Xishuangbanna in haze months, accounting for 14%. The two countries making the greatest contributions to BCBB transported to Xishuangbanna were Myanmar and Laos in haze months, accounting for 55% and 13%, respectively. BC emissions from Xishuangbanna had minimal effects on the results of the present study. It is suggested that open BB in Myanmar and Laos, and anthropogenic emissions in India were responsible for poor air quality in Xishuangbanna.  相似文献   
36.
浅谈企业环境信息公开   总被引:2,自引:0,他引:2  
现代环境管理强调公众参与.其前提是环境信息对公众的公开.企业主动披露其环境信息属于其中一种方式.本文通过阐述企业环境信息公开对于环境改善和促进企业发展的作用,针对中国现阶段企业环境信息公开的状况和存在的问题,提出了相关的建议,希望借此推动更多的企业开展环境信息公开.  相似文献   
37.
宫照  高波 《环境与发展》2020,(2):131-132
以第一次全国地理国情普查与基础性地理国情监测数据为数据源,开展西藏芒康滇金丝猴国家级自然保护区内2015、2016、2017、2018年自然保护区建设与管理情况监测,分别从人工地物、林草资源、露天采掘场等方面进行统计,分析人类活动对自然保护区内的生态系统胁迫以及区内生态恢复情况等。  相似文献   
38.
Trophy hunting can provide economic incentives to conserve wild species, but it can also involve risk when rare species are hunted. The anthropogenic Allee effect (AAE) is a conceptual model that seeks to explain how rarity may spread the seeds of further endangerment. The AAE model has increasingly been invoked in the context of trophy hunting, increasing concerns that such hunting may undermine rather than enhance conservation efforts. We question the appropriateness of uncritically applying the AAE model to trophy hunting for 4 reasons. First, the AAE assumes an open‐access resource, which is a poor characterization of most trophy‐hunting programs and obscures the potential for state, communal, or private‐property use rights to generate positive incentives for conservation. Second, study results that show the price of hunting increases as the rarity of the animal increases are insufficient to indicate the presence of AAE. Third, AAE ignores the existence of biological and behavioral factors operating in most trophy‐hunting contexts that tend to regulate the effect of hunting. We argue that site‐specific data, rather than aggregated hunting statistics, are required to demonstrate that patterns of unsustainable exploitation can be well explained by an AAE model. Instead, we suggest that conservation managers seeking to investigate and identify constraints that limit the potential conservation role of trophy hunting, should focus on the critical governance characteristics that shape the potential conservation role of trophy hunting, such as corruption, insecure property rights, and inadequate sharing of benefits with local people. Aplicación del Modelo Antropogénico del Efecto Allee sobre la Caza de Trofeos como una Herramienta de Conservación  相似文献   
39.
基于无线局域网(WLAN)的油田安全监控系统研究   总被引:1,自引:1,他引:0  
针对油田监控对象具有点多、面广、跨区域的特点,指出对油田进行无线监控的必要性,并对6种常见的无线通信手段的特点进行比较;根据油田安全监控的业务需求,提出基于WLAN技术的油田安全监控系统硬件结构和软件功能设计方案;并结合工程实施案例介绍系统中无线设备的选型、安装和防雷接地等方面的工程问题。该研究成果实现油田的安全监控预警,减少或避免事故发生的可能性,有利于提高油田安全管理的科学性,具有实用推广价值。  相似文献   
40.
Reaching the economic, environmental and sustainability objectives of all societies requires overcoming several major energy challenges; it necessitates rapid progress in multiple areas. The scenario pathways presented in this paper describe transformative changes toward these goals, taking a broad view of the four main energy challenges faced by society in the 21st century: providing universal access to modern energy for all; reducing the impacts of energy production on human health and the environment; avoiding dangerous climate change; and enhancing energy security. The overarching objective of the paper is to provide policy guidance on how to facilitate the transformation of the energy system to achieve these multiple energy objectives. Particular focus is given to the required pace of the transformation at both the global and regional levels, and to the types of financial and policy measures that will be needed to ensure a successful transition. Synergies and trade‐offs between the objectives are identified, and co‐benefits quantified. The paper makes an important contribution to the scenario literature by approaching the global transition toward sustainable development in a more integrated, holistic manner than is common in other studies.  相似文献   
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