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991.
Abstract

From angles of administrative law and private law, the article analyzes relations between environmental right for citizens and the right to use environmental resources owned by company and enterprise and points out three principles to balancing two relations: A principle of equal protection, a principle that general interest is superior to special interest as well as taking an account for special interest, in specific circumstances, for example, in the circumstance that clashes between environmental and economic interests can not be avoided, policy makers can put an emphasis on more important social interest according after considering weight of each interest. Finally, the article reaches a conclusion that China should establish system of environmental right for citizens from legislative and administrative levels so that a harmonious society can be constructed with guarantee.  相似文献   
992.
The influence of anthropogenic activities,especially artificial dykes,on the coastal wetland landscape is now considered as a serious problem to the coastal ecosystem.It is important and necessary to analyze changes of coastal landscape pattern under the influence of artificial dykes for the protection and management of coastal wetland.Our study aimed to reveal the quantitative characteristics of the coastal wetland landscape and its spatial-temporal dynamics under the influence of artificial dykes in the Yellow River delta(YRD).It was analyzed by the methods of the statistical analysis of landscape structure,five selected landscape indices and the changes of spatial centroids of three typical wetland types,including reed marshes,tidal fiats and aquaculture-salt fields.The results showed that:(1)Reduction of wetland area,especially the degradation of natural wetlands,had been the principal problem since the dykes were constructed in the YRD.The dykes created conditions for the development of artificial wetlands.However,the new born artificial wetlands were still less than the vanished natural wetlands.(2)Compared with the open area,the building of artificial dykes significantly speeded up the changes of landscape patterns and the aggravation of the landscape fragmentation in the closed area.(3)The changes of area-weighted centroids of three typical wetland landscapes were greatly affected by dykes,and the movement of the centroid of the aquaculture-salt field was very sensitive to the dykes constructed in the corresponding period.  相似文献   
993.
Abstract

Agglomeration of the Yangtze Delta (UAYD), one of the most developed regions of China, has witnessed an increasing prevalence in building ecological cities when the ecological cities are pursued by many modern cities, and great achievements have been made in this regard. It is inevitable, however, that certain problems exist during the construction of ecological city, which include but not limited to non-harmonious development of urban complex ecosystem, and the difficulty in quantifying eco-city construction or incomplete quantification in assessing the construction of present and future eco-city. Based on the analysis on social-economic conditions and regional conditions of the UAYD, this paper attempts to set up an index system of eco-cities combining with local characteristics, and to adopt the indices of eco-city, urban harmony, and eco-city colligate to evaluate the ecological level, urban harmonious development and eco-city construction of cities within the UAYD. Results indicate that among 15 cities in UAYD, Suzhou City ranks the highest in terms of eco-city construction, whereas Nantong ranks relatively lower; sustainable eco-city construction is possible only when cities are developed in every respect of harmony.  相似文献   
994.
Abstract

It is difficult to manage the manufacturing hazardous waste (MHW) which is generated from a huge amount of complicated sources and causes very serious pollution. Therefore more and more attention has been paid to MHW pollution. Shanghai, as an industrial and economic center and an international metropolis in China, has a vast industrial system spanning a multitude of sectors, which generates MHW not only in a huge magnitude but also in a large variety of types from complicated sources, resulting in severe pollution. In 2003, the production of MHW in Shanghai is about 3.96 × 105 ton, involving 33 indices. Most of MHW in Shanghai is treated and disposed of, but a significant portion is not handled properly and effectively. This paper carries out in-field investigation on the current status of MHW production and treatment in Shanghai, and puts forward scientific proposals that Shanghai should facilitate cleaner production and minimize hazardous waste; strictly enforce hazardous waste registration system, strengthen monitoring the certified enterprises; strengthen intent disposal center construction and realize hazardous waste reclamation; accelerate establishing the technical criteria and the management policy, promote the research and development on the treatment and disposal technology, and strengthen information management, thus realizing integrated management on MHW pollution.  相似文献   
995.
Abstract

In recent years, with the rapid development of the tourist industry, world heritage sites become more and more popular among tourists from home and abroad. Therefore, heritage tourism has become a new hotspot. However, while world heritage sites are making obvious economic benefit from tourism, they also bring various problems and contradictions, of which the most troublesome one is the contradiction between heritage conservation and tourism development. To discuss and analyze the root and the essence of the above contradiction and find a way to bring about harmony between them is an important program faced by our national heritage management practice and academic research. Based on the case of cleaning the Temple and Cemetery of Confucius and the Kong Family Mansion in Qufu, this paper analyzes the reasons why our national world cultural heritage sites bring about the above contradiction in the process of tourism development and points out that the improper system and stakeholders' benefit imbroglio are respectively the root and the essence of the contraction. Then, it also puts forward corresponding solutions.  相似文献   
996.
Abstract

As a typical tropical agro-forestry ecosystem in Wenchang, Hainan Province, China, rational mechanisms of the rubber-tea-chicken eco-agricultural model were studied with the Solow technological level index, stability indicator, harmonizing coefficient, grey correlation coefficient and production dominance. This study focused on rational hierarchical structure, the limiting factors and optimal strategies of the model development based on model structure, resource conditions and external market demands. Results showed that rational mechanism of the rubber-tea-chicken ecosystem model mainly included technological contributions, leverage function of dominance component (livestock husbandry), stability of the model structure and harmony of its components, the model dominant product’s market demand and government’s supporting policies. The contributions of fund, technology, information and talent resources played an important role in improving sustainability and productivity of the agro-forestry model.  相似文献   
997.
ABSTRACT

Scholars and practitioners have focused in recent years on the potential for achieving cooperation in small “clubs” of countries. While solutions to global climate change will eventually require widespread cooperation, club strategies could help to catalyze that outcome. Unlike the Paris Agreement, which has achieved widespread but relatively shallow cooperation, it could be easier to tailor agreements that allow deep cooperation within smaller groups. This essay extends that logic to clubs whose geometry varies two-dimensionally across countries but also along a third dimension: within countries. Most of the key elements of international relations and international law theory that explain how clubs achieve cooperation are directly applicable to three-dimensional clubs. Most of the relevant experience for these clubs has occurred in the west; overdue is a close assessment of how key units – such as provinces and firms – within China and other emerging economies.  相似文献   
998.
以黄河三角洲为典型研究区,通过分析区域地表污染物流失风险与入海通量的关系,构建了海岸带农业总氮(TN)和总磷(TP)面源污染排海估算模型.在此基础上,计算了包含水田、水浇地和旱地等耕地类的TN和TP面源污染排海系数,验证表明输出系数估算结果较好.研究区耕地的TN和TP排海系数分别为18.33 kg·(hm2·a)-1和1.02 kg·(hm2·a)-1,在夏季面源污染负荷较高.子流域尺度较大的耕地类农业面源污染负荷主要位于支脉河、广利河和小岛河管控区域.TN和TP总负荷较大的行政区主要位于北部黄河口镇和永安镇;较大的单位面积负荷在西南部.因此,需要关注农业面源污染的时间效应,同时协调社会经济发展,从子流域和行政单元的角度制定综合性面源污染防控策略,陆海统筹治理海域污染.  相似文献   
999.
侯露  朱媛媛  刘冰  李健军 《环境科学》2023,44(11):5899-5914
对比分析2015~2022年冬奥会期间(1月31日至2月20日)京津冀及周边区域44城市空气质量时空演变特征,量化同期气象、协同减排和跨区域传输对PM2.5浓度及组分变化贡献,为不利气象条件下区域空气质量联防联控提供科学参考.结果表明,2022年44城市PM2.5浓度为近8年农历同期最低(46μg·m-3),优良天占比最高(83.3%),不存在重污染天.PM2.5污染南重北轻,高值区主要集中在太行山沿线及燕山传输通道城市.2016年在春节中期未管控烟花爆竹燃放等源排放强度下,优良天占比93.5%,大气强扩散能力对空气质量改善至关重要.2022年静稳天气指数(SWI)同比增加2.1,大气扩散能力转差,44城市ρ(PM2.5)均值和峰值同比下降14μg·m-3和76μg·m-3,北京减排对PM2.5浓度降幅较未采取前增大96%,晋鲁豫地区在气象造成PM2.5浓度上升的不利背景下,峰值下降87μg...  相似文献   
1000.
Material recovery processes are presented as the optimum option for recycling plastic wastes as a means of recovering hydrocarbon resources. There exist a large variety of automated material recovery processes for recycling of such wastes but each with significant limitations. Of these, the separation based on differences in densities is advocated as the optimum process either for producing recycled products or preparing wastes for subsequent recovery processing.Density separation processes based on cyclone type density media separation (DMS) is presented as an important, potential method for increasing plastics recycling process capacities. It is demonstrated to have the capacity to separate a significantly larger range of particle sizes than those presently processed industrially. The mathematical relationship for the prediction of quality of typical LARCODEMS type density media separations by particle size and density as expressed by the Ecart Probable is presented.A proposed device configuration is presented for density media separation to optimize the recovery and purity of both density fractions produced. It is also suggested that to be economically viable, a large scale of operation is required for industrial plastics recycling operations recovering and producing a number of different plastics with a purity to be used as a substitute for virgin material.  相似文献   
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