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991.
目前,我国的土地整治已进入生态化土地整治阶段。作为一种多类型、多尺度的综合生态治理系统,生态化土地整治可以从区域和工程尺度开展村域空间布局和工程设计,营造村域生态空间、生产空间和生活空间。村域生态空间营造可以通过村域绿色基础设施构建,形成绿色网络空间;村域生产空间(主要是农业生产空间)营造主要是通过生态化农田整理工程布局和单体工程设计,提升生态服务价值;村落生活空间营造可以通过村落空间格局塑造、街巷空间组织,庭院空间布局和公共空间建设等多个层次,形成营造适宜的居住空间。  相似文献   
992.
海洋微微型蓝细菌分子生态学研究进展   总被引:2,自引:0,他引:2  
微微型蓝细菌是迄今发现最小也是最古老的光合自养生物,在海洋中分布极广且丰度较高,作为重要的初级生产者对全球碳循环和海洋食物网具有重要贡献。在长期进化中微微型蓝细菌形成简并基因组和高度多样性,其分子生态学的研究能够为理解生物的基因型、表型与生态型的关系以及生物的适应性进化提供关键科学依据。借助分子生物技术的发展,海洋微微型蓝细菌分子生态学近年来的研究揭示了其分布的时空变化特征、不同亚型微尺度分布差异及影响分布的主要环境因子,探讨了环境因子影响下基因组在功能和表达上传递的适应机制信息。通过进一步扩充和挖掘基因组信息,结合分布规律论证微微型蓝细菌在分子水平上的环境适应机制,是实现生态系统微微型蓝细菌功能模块精细化数值模拟的关键,也是未来研究的主要方向和重要内容。  相似文献   
993.
This paper applies the ecological modernization (EM) framework to analyze China’s green building program. EM focuses on the effective institutionalization of environmental objectives into respective political and economic systems, and thus provides valuable insights into the roles of the state and other stake holders in environmental regulation. Since the mid-2000s, the Chinese government has advanced an aggressive green building campaign, which is distinguished by its speed, scale, and evolution from one of voluntary participation to a top-down implementation through administrative hierarchies. While this has resulted in a remarkable growth of green building projects, questions remain about the effectiveness and sustainability of such a state-centered approach. Though interviews with officials, planners, architects, real estate developers, and property managers in several Chinese cities, data analysis of the green building stock, and surveys of architects, this paper analyzes Chinese green building patterns and situates such patterns among the contradictory motivations of different levels of government and their relationships to different stake holders. This research finds that the top-down state apparatus is not sufficient to overcome these contradictions and the profit motives of the property developers. However, many under-developed opportunities exist to leverage property developers, building professionals, and the public to engage in green building practices. In the end, I argue that the state must embrace reform to build flexible and collaborative movements with other parties with strong public participation. China’s ecological modernization process may feature a stronger state and faster changes, but it is not exempted from the need of political modernization.  相似文献   
994.
The old Senhora das Fontes uranium mine, in central Portugal, consists of quartz veins which penetrated along fracture shear zones at the contact between graphite schist and orthogneiss. The mine was exploited underground until a depth of 90 m and was closed down in 1971. The ores from this mine and two others were treated in the mine area by the heap-leach process which ended in 1982. Seven dumps containing a total of about 33,800 m3 of material and partially covered by natural vegetation were left in the mine area. A remediation process took place from May 2010 to January 2011. The material deposited in dumps was relocated and covered with erosion resisting covers. Surface water and groundwater were collected in the wet season just before the remediation, in the following season at the beginning of the remediation and also after the remediation in the following dry season. Before, at the beginning and after the remediation, surface water and groundwater have an acid-to-alkaline pH, which decreased with the remediation, whereas Eh increased. In general, before the remediation, uranium concentration was up to 83 μg/L in surface water and up to 116 μg/L in groundwater, whereas at the beginning of the remediation it increases up to 183 μg/L and 272 μg/L in the former and the latter, respectively, due to the remobilization of mine dumps and pyrite and chalcopyrite exposures, responsible for the pH decrease. In general, after the remediation, the U concentration decreased significantly in surface water and groundwater at the north part of the mine area, but increased in both, particularly in the latter up to 774 μg/L in the south and southwest parts of this area, attributed to the remobilization of sulphides that caused mobilization of metals and arsenic which migrated to the groundwater flow. Uranium is adsorbed in clay minerals, but also in goethite as indicated by the geochemical modelling. After the remediation, the saturation indices of oxyhydroxides decrease as pH decreases. The remediation also caused decrease in Cd, Co, Cr, Ni, Pb, Zn, Cu, As, Sr and Mn concentrations of surface water and groundwater, particularly in the north part of the mine area, which is supported by the speciation modelling that shows the decrease of most dissolved bivalent species. However, in general, after the remediation, Th, Cd, Al, Li, Pb, Sr and As concentrations increased in groundwater and surface water at south and southwest of the mine area. Before and after the remediation, surface water and groundwater are contaminated in U, Cd, Cr, Al, Mn, Ni, Pb, Cu and As. Remediation caused only some improvement at north of the mine area, because at south and southwest part, after the remediation, the groundwater is more contaminated than before the remediation.  相似文献   
995.
城市景观格局动态及其规划的生态学探讨   总被引:12,自引:2,他引:10  
城市作为人类的主要栖居地,其景观格局和生态效应直接影响到世界人口的生存质量。从景观生态学的视角出发,以国内外近年来关于城市景观格局动态及其生态效应的理论和实证研究为材料,整理并总结了城市景观格局的特征、研究方法和演变机制。在文献综述和具体案例分析的基础上,尝试性地提出城市景观格局动态的“类库兹涅茨曲线”现象,即在从城市化初期到城市发展相对成熟的一个周期内,景观破碎化程度呈现“快速增加—增速减缓—平稳下降”的过程,并探讨了这一规律的适用性和特征。在此基础上,进一步讨论了城市景观及其格局变化对生态环境的影响,指出在城市景观规划中充分结合生态学原理,是实现城市可持续发展的必经之路。  相似文献   
996.
PRB技术处理污染地下水的影响因素分析   总被引:10,自引:1,他引:9  
设计了6个可渗透反应屏障(PRB)反应器,分别对污染物在反应器内的滞留时间、反应介质、DO、NO-3 、SO 2- 4、pH、Eh等因素对PRB的影响进行了研究和分析.实验结果表明:在相同条件下,污染物的处理效果与滞留时间直接相关;零价铁对复杂的不可生物降解或难生物降解的有机物向简单有机物的转化起了重要作用,经过反应器后使ρ(BOD5 )/ρ(COD)值从初始0.32增至0.5~0.79,增强了有机物的可生物降解性;不同的辅助反应介质对污染物的去除具有一定的选择性.  相似文献   
997.
利用宁波四明山区域气象观测站逐日和逐小时气象要素观测资料,分析该区域气候条件,并以舒适度指标等评估其气候生态。结果表明,1961—2017年四明山区域气温持续上升,降水增多,日降水峰值集中在16—18时且未出现明显变化,小风日数增多,气候适宜日数明显增加。气温是影响该区域人体舒适度的主因,其次是相对湿度和风;春秋舒适日数多,气候温润,日晴夜雨特征明显;夏季凉爽,是理想的避暑休闲胜地;年舒适时数高山与平原相近,但季节差异明显,夏季高山地区非常舒适,其他三季平原更舒适。区域气候模式结果显示,未来四明山区域气温继续维持升高趋势,降水有所增加,极端高温事件增多,极端低温事件减少,人体舒适日数呈减少趋势,春、秋季略增加,夏季减少明显。  相似文献   
998.
对我国国土生态安全格局与空间管理策略的思考   总被引:1,自引:0,他引:1  
本文从生态安全格局的定义、我国生态安全格局现状、生态安全格局优化3个方面进行了分析,明确了目前及未来生态保护用地面积比例,并提出了国土生态安全的空间管制策略,主要包括:重点生态功能区域根据主导生态功能的差异性采取不同的管理措施,在土地利用规划体系中新增生态保护用地以实现生态功能的落地,以生态保护红线为基础统筹各类自然保护地。研究成果可为保障我国国土生态安全,促进社会-经济-生态之间的协调发展提供依据。  相似文献   
999.
废弃砖瓦窑厂土地复垦技术包括工程复垦和生物复垦,在具体实施复垦方案时,要遵循生态学原理。工程复垦阶段,除了使被破坏土地恢复到可供利用的物理状态,还要考虑改善生态环境和生物多样性;生物复垦阶段,要按照生物与环境协同进化原理、生态结构稳定性与功能协调性等原理,采用施肥法、绿肥法、微生物法、管理法恢复土壤肥力与生物生产能力。淮安市淮安区范集镇大花村在废弃砖瓦窑厂土地复垦项目中,依据生态学理论,因地制宜,采取适宜的方案进行土地复垦,实现了生态环境的良性循环及土地资源的可持续利用。  相似文献   
1000.
No clear definition of sustainable development exists to guide politicians in solving challenges at the global or regional levels. Rather, the concept's use has increasingly reflected socially desirable attributes of solutions to local- and project-level problems, but these ignore the global challenges that the concept was meant to address. We return to the original definition of sustainable development used in the Brundtland Report and suggest an assessment method to determine whether countries currently meet the threshold values of four equally important primary dimensions: safeguarding long-term ecological sustainability, satisfying basic needs, and promoting intragenerational and intergenerational equity. We also define indicators and threshold values for each of these dimensions; in addition, we show how 167 countries compare in meeting these threshold values. Currently, no country meets all four thresholds. Even so, we propose that, with the use of technology and behavioural changes, it will be possible to reach the threshold values by 2030.  相似文献   
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