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21.
动物养殖场是空气环境微生物污染的重要来源,然而目前关于养殖场空气中微生物污染特征的时间规律少有报道.针对以上情况,以蛋鸡场为例,采用16SrRNA基因扩增子测序分别对养殖场空气和粪便环境中细菌分布特点及呼吸暴露展开为期80余周的研究.结果表明,空气和粪便样本中16S rRNA含量范围分别在6.08×105~4.90×106 copies·m-3和4.27×108~1.15×1010 copies·g-1之间.空气中细菌浓度的平均值在冬季显著高于夏季,而生物多样性则呈现相反趋势.蛋鸡场空气与粪便中的优势细菌门均为厚壁菌门(Finnicutes).在所调查时间内,空气中前3个优势菌属的种类较为稳定,依次为乳杆菌属(Lactobacillus)、拟杆菌属(Bacteroides)和栖粪杆菌属(Faecalibacterium),而粪便中优势菌属则随养殖时间的增加波动较大.空气和动物粪便中细菌和致病菌群落结构的相关性均不显著,但不同介质中两种目标微生物的含量均显著相关.粪便中细菌的气溶胶化指数随养殖时间的增加而呈上升趋势,而致病菌趋势相反.其中,瘤胃菌科torques属([Ruminiococcus]_torques_group)、拟杆菌属(Bacteroides)和栖粪杆菌属(Faecalibacterium)为最易发生气溶胶化的前3个致病菌属.养鸡场工人的细菌呼吸暴露具有季节性差异,其中细菌和致病菌摄入量的平均值分别为2.54×107 copies·d-1和2.87×105 copies·d-1.研究结果将为系统评估养殖场空气微生物的污染特征和潜在健康风险,对以及制定相应的职业暴露行业标准和防控措施提供科学依据.  相似文献   
22.
It is 10 years since the adoption of the Cape Town Principles and Best Practices on the Prevention of Recruitment of Children into the Armed Forces and on Demobilization and Social Reintegration of Child Soldiers in Africa. The field of programming for the reintegration of children associated with armed forces and armed groups has made significant strides in this period. However, important gaps in the knowledge base remain. This paper examines empirical evidence that supports lessons learned from work with children formerly connected with fighting forces. It evaluates what is known, where promising practice exists, and lacunae in five programming areas: psychosocial support and care; community acceptance; education, training and livelihoods; inclusive programming for all war-affected children; and follow-up and monitoring. While the 2007 Paris Commitments to Protect Children from Unlawful Recruitment or Use by Armed Forces or Groups mark an emerging consensus on many issues, there is still a critical need for more systematic studies to develop the evidence base supporting intervention in this area.  相似文献   
23.
    
The Paris Agreement?s nationally determined contributions (NDCs) provide an excellent point of entry to simultaneously address climate change and the 2030 Agenda for Sustainable Development and its Sustainable Development Goals (SDGs). This study sets out to explore the connections between climate action plans (NDCs) and each of the 17 Sustainable Development Goals (SDGs). In this study, we used four levels of visibility, that is, present, generic, implied and absent to provide a broad perspective of the extent to which South Africa?s NDC is aligned with the targets of the SDGs. Our results revealed that South Africa?s NDC has 12% present level of visibility to the SDG targets, with SDG 7 Affordable and Clean Energy and SDG 13 Climate Action showing the highest representation of present level of visibility. By contrast, the absent level of visibility NDC showed 53% in the SDG targets, with SDG 5 Gender Equity, SDG 16 Peace, Justice and Strong Institutions and SDG 3 Good Health and Well‐Being, showing the highest representation of absent level of visibility. These results indicate that there is scope to improve the alignment of South Africa?s NDCs with the SDG targets. To this end, we have identified areas that may benefit with further elaboration in the country?s second NDC.  相似文献   
24.
ABSTRACT

Comparing and evaluating the Nationally Determined Contribution (NDC) is an important element in global stocktake in the post-Paris climate negotiations, aimed at closing the emissions gap with the Paris Agreement goals. To date, however, there has still been no explicit guideline or method. By applying emissions allowance allocated by 16 schemes as benchmarks, this paper tries to compare and evaluate the NDCs of the top six emitters, which jointly account for about 70% of the world’s CO2 emissions. Results show that the four developed countries’ NDCs lack ambition with respect to most allocations under 2°C and all under 1.5°C, indicating they need to substantially ratchet up their NDCs and lead elevating mitigation. Evaluating cumulative emissions is more likely to clarify the ambition and fairness of China’s NDC. If considering cumulative emissions, China’s NDC is aligned with the median of cumulative allowances under 2°C and within the 1.5°C range. The Paris Agreement invited the Parties to communicate the mid-century low emissions strategies. This paper also tries to explore the mid-century mitigation in the perspective of allocations, which might provide decision-makers with some useful information when envisaging the post-NDC mitigation.  相似文献   
25.
四川重楼属药用植物资源研究   总被引:10,自引:0,他引:10  
经调查鉴定,四川重楼属药用植物有10种7变种,均在我省民间广泛应用。目前川产商品重楼原植物有3种6变种,除中国药典收载的华重楼和滇重楼外,其分布广、产量大的还有七叶一枝花、狭小重楼和短梗重楼等3种4变种。  相似文献   
26.
    
Based on the greenwashing approach in line with legitimacy theory, we examine first whether the strategic positioning of key oil companies is addressed by their disclosed commitments in their corporate reports and, second, whether the disclosures made by oil companies in relation to energy transition reflect their behavior. We use an ordinal logistic regression model in a sample of 38 oil companies, our findings suggest that the lower the investment in oil and gas exploration and production, and the smaller the variation in the volume of hydrocarbon reserves, the more likely a company narrates a strong commitment to the energy transition. Also, we consider that investments in fossil fuels need to be reduced significantly to accelerate the transition to cleaner and sustainable energy sources, and it is vital to observe the alignment of disclosed commitments by companies to the transition and their behavior, avoiding the accusation of greenwashing practices.  相似文献   
27.
制定净零排放目标的企业数量快速增长助推自愿碳市场迅猛发展。由于能够吸引私营部门资金、降低新兴技术成本、助力难减排领域的减排行动,自愿碳市场可在弥合目前的减排差距方面发挥重要作用。《巴黎协定》确定的全球温升控制目标促进了碳中和行动的广泛开展,对自愿碳市场的运行提出了新的要求。本文深入分析了自愿碳市场在新气候治理阶段中面临的机遇和挑战,识别了影响未来自愿碳市场运行的关键要素,总结了自愿碳市场的四种主要运行模式及其发展路径。同时,本文从项目开发商、需求侧企业和政府等三个层面系统分析了新形势下自愿碳市场对我国的影响并给出了对策建议。  相似文献   
28.
通过野外调查和历史文献及标本统计分析,确定并分析北洛河流域种子植物信息数据.结果表明:该区共有种子植物123科581属1671种,占黄土高原种子植物的83.67%、67.24%、51.83%,集中分布于大型科(>50种)、较大科(21~50种)和单种属(1种)、小型属(2~5种)内.11个干流流经的地理单元植物相似性聚类分为5组,较早分离的是黄龙县,最大类因子午岭山脉连接而包含4个地理单元(富县、合水县、宜君县、黄陵县).富县、合水县和黄龙县植物丰富度SD值最高,洛川县、华池县和甘泉县SD值最低.该区地理成分在属级水平上有15个分布区类型16个变型,以温带分布及其变型为主(287属,占49.40%),并与热带分布及其变型联系紧密(115属,占19.79%),植物丰富度SD值与温带成分显著正相关;黄陵县、洛川县、黄龙县R/T值最高,热带性质最强,华池县、定边县R/T值最低,热带性质最弱.R/T值受海拔影响,随温度和降水从东南向西北递减.该区植物起源古老,分化程度高,物种多样性丰富,地理成分复杂,是重要的植物种质资源库.植物物种多样性地带性格局过渡性明显,体现出这些类群的生态位需求.需加强保护该区原生环境和植物,合理开发利用,可选择6大优势科(菊科、禾本科、蔷薇科、豆科、唇形科和毛茛科)中适地适树适草的物种(温带性质),进行植被恢复和水土流失治理.  相似文献   
29.
巴黎协定生效下的中国省际碳排放权分配研究   总被引:3,自引:0,他引:3       下载免费PDF全文
随着《巴黎协定》正式生效,碳排放权作为关系人类福祉的一种新型发展权,如何分配已成为世界各国共同关注的焦点问题.中国是全球最大的碳排放国,面临着巨大的减排压力.为分解落实我国政府提出的2030年碳减排\"自主行动目标\",提出公平性、效率性、可行性、可持续性4项分配原则,从社会、经济、环境三重维度系统选取分配指标,构建\"共同但有区别\"的省际碳排放权分配模型,据此对31个省区2016—2030年的碳排放配额进行核算.研究表明,碳排放配额最多为广东、山东和江苏,最少为西藏、新疆和青海.对比配额结果与当前碳排放规模发现,山西等9省区未来的碳排放空间呈现赤字,海南等16省区的碳排放空间呈现盈余,浙江等6省区则收支大致相抵.鉴于各省区面临不同的减排任务和压力,差别化的控排政策是保证我国\"2030目标\"顺利实现的关键.  相似文献   
30.
    
The transparency framework of the Paris Agreement (PA) will be elaborated from the existing arrangements under the UN Framework Convention on Climate Change (UNFCCC). Yet, the capacities of developing countries to regularly report national GHG inventories vary, and their needs for capacity building are closely linked with efforts and achievements of previous inventory preparation. The purpose of this study was to analyze the status and changes in the capacity of 37 developing countries in Asia by using a matrix of capacity-indicators. Indicators were composed for four assessment categories: (1) international engagement of a country in the GHG inventory-related process; (2) institutional capacity to produce a GHG inventory; (3) existing technical capacity available to develop a GHG inventory; and (4) actual technical capacity applied to produce a GHG inventory. The paper also analyzed the scale of international support and variations in meeting with capacity building needs. Eleven countries were identified as having low capacity over time, while 9 improved their capacity. Seventeen countries, including 7 countries with established capacity, continuously had relatively high capacity over time. International support was scarce in the majority of Asian developing countries with the most capacity building needs. Improvements in basic technical capacity available for GHG inventory preparation, such as statistics and the scientific expertise, were found to be a key necessity for countries to respond to the PA’s enhanced transparency framework. Based on these findings, the study recommended increasing support for improvements in basic technical capacity, especially in countries where existing capacity is low and support is limited. Such capacity building efforts are also beneficial for countries to form and implement nationally determined contributions (NDCs) and other economic and development policies.  相似文献   
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