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排序方式: 共有1154条查询结果,搜索用时 953 毫秒
931.
932.
Anders Stigebrandt Bengt Liljebladh Loreto de Brabandere Michael Forth ?ke Granmo Per Hall Jonatan Hammar Daniel Hansson Mikhail Kononets Marina Magnusson Fredrik Norén Lars Rahm Alexander H. Treusch Lena Viktorsson 《Ambio》2015,44(1):42-54
In a 2.5-year-long environmental engineering experiment in the By Fjord, surface water was pumped into the deepwater where the frequency of deepwater renewals increased by a factor of 10. During the experiment, the deepwater became long-term oxic, and nitrate became the dominating dissolved inorganic nitrogen component. The amount of phosphate in the water column decreased by a factor of 5 due to the increase in flushing and reduction in the leakage of phosphate from the sediments when the sediment surface became oxidized. Oxygenation of the sediments did not increase the leakage of toxic metals and organic pollutants. The bacterial community was the first to show changes after the oxygenation, with aerobic bacteria also thriving in the deepwater. The earlier azoic deepwater bottom sediments were colonized by animals. No structural difference between the phytoplankton communities in the By Fjord and the adjacent Havsten Fjord, with oxygenated deepwater, could be detected during the experiment.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-014-0524-9) contains supplementary material, which is available to authorized users. 相似文献933.
A Review of the Elements of Human Well-Being with an Emphasis on the Contribution of Ecosystem Services 总被引:7,自引:0,他引:7
Natural ecosystems perform fundamental life-support services upon which human civilization depends. However, many people believe that nature provides these services for free and therefore, they are of little or no value. While we do not pay for them, we pay significantly for their loss in terms of wastewater treatment facilities, moratoriums on greenhouse gases, increased illnesses, reduced soil fertility and losses in those images of nature that contribute to our basic happiness. Little is understood about the well-being benefits of the natural environment and its ecosystem services. The interwoven relationship of ecosystems and human well-being is insufficiently acknowledged in the wider philosophical, social, and economic well-being literature. In this article, we discuss an approach to examine human well-being and the interactions of its four primary elements-basic human needs, economic needs, environmental needs, and subjective well-being-and ecosystem services. 相似文献
934.
Biphasic effects of lanthanum on Vicia faba L. seedlings under cadmium stress, implicating finite antioxidation and potential ecological risk 总被引:3,自引:0,他引:3
In the present study, lanthanum (La) as a representative REE was used to explore the mechanisms for alleviation of Cd-induced oxidative damage by extraneous La at appropriate concentrations, and to assess ecological risk of combination of Cd and La at higher concentrations in roots of Vicia faba L. seedlings. The seedlings were hydroponically cultured for 15 d under nutrient solution, 6 μmol L−1 CdCl2, and combination of 6 μmol L−1 CdCl2 and increasing concentrations of La, respectively. The results showed that the supplementation with low concentrations of exogenous La (<120 μmol L−1) led to reduced contents of Cd, Ca, Cu, Zn, Mn or Fe element and increased activities of superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (GPX) and ascorbate peroxidase (APX) isozymes as well as heat shock protein 70 (HSP 70) production in the roots. However, the supplementation with higher La (>120 μmol L−1) showed the adverse effects. The contents of Cd elevated above the single Cd treatment in the roots, accompanying with the decline of antioxidant isozyme’s activities and HSP 70, and increment of carbonylated proteins and endoprotease isozyme’s activities. The results also showed that the root growth was not only related to carbonylated proteins, but also to indole acetic acid oxidase activities. Therefore, the supplemented extraneous La contributed to biphasic effects: stimulated antioxidation at lower concentrations and pro-oxidation at higher concentrations against Cd-induced oxidative stress in the roots. 相似文献
935.
基于淮北中湖采煤沉陷区2005年、2014年和2018年的遥感影像进行地表景观解译,研究治理前后该区景观格局变化特征及生态效应.结果表明:治理前,该区耕地破碎化加剧、景观优势最大并持续减弱,沉陷积水区水体呈聚集化趋势;治理后,景观基质由耕地变为水体,林地、草地面积显著增加且景观优势上升,人工湖泊水体聚集程度高.区域景观... 相似文献
936.
937.
山区生态产业是依赖于山区丰富的自然资源按照生态学原理组织形成的生态与经济有机统一的产业发展形式。本文阐述了山区生态产业七个方面的特征:即山区生态产业对自然资源的特殊依赖性、受高度景观带的制约性、结构多样性与复杂性、建设长期性、经济收益级差性、开发水平落后性和开发任务艰巨性。在此基础上,文章从要素调控设计、垂直带幅生态调控设计、产业模式系统生态设计出发探讨了生态产业与垂直地带性的构建关系,并举例说明了山区生态产业开发建设对环境保护的积极作用。得出了山区生态产业的开发就是努力避免产业活动对生态环境干扰的逆向作用,积极引导与实现产业活动对生态环境干扰的正向作用的结论。 相似文献
938.
生态环境监测是生态文明建设的重要支撑。在设区市级环境监测监控能力普遍较弱、生态环境保护压力巨大的双重背景下,编制设区市生态环境监测监控规划具有重要意义。在调查了江苏省部分设区市环境监测监控规划的基础上,总结了规划编制在监测监控网络建设、监测监控能力建设、质量管理、大数据应用建设、人才队伍建设等方面的主要内容,针对规划中普遍存在的组织架构不清晰、特色发展定位不明确、环境监测监控融合发展谋划不足、项目建设可行性论证不够等关键问题,提出应理顺组织架构、明确特色发展定位、加强环境监测监控一体化发展谋划、加强项目建设可行性论证等对策建议,以期为今后的规划编制工作提供相关借鉴。 相似文献
939.
长江扬州段是南水北调东线的源头水域,也是江淮生态大走廊的核心区,生态区域敏感性和重要性尤为突出。通过高分辨率卫星遥感筛查-无人机遥感详查-地面人工核查的星空地协同技术对长江扬州段沿岸自然岸线保有率、土地利用状况以及周边环境风险源进行全面调查。结果表明:(1)长江扬州段自然岸线保有率为46.20%,岸线范围内建设用地占比达33.35%,开发强度较高;(2)沿岸有码头114座,入江排口104个,部分排口存在水色异常等环境问题;(3)沿江生态保护红线区域内存在加油船溢油现象和驳船违规堆放固体废弃物等环境安全隐患。 相似文献
940.
Refining the ecological footprint 总被引:8,自引:0,他引:8
Ecological footprint measures how much of the biosphere’s annual regenerative capacity is required to renew the natural resources
used by a defined population in a given year. Ecological footprint analysis (EFA) compares the footprint with biocapacity.
When a population’s footprint is greater than biocapacity it is reported to be engaging in ecological overshoot. Recent estimates
show that humanity’s footprint exceeds Earth’s biocapacity by 23%. Despite increasing popularity of EFA, definitional, theoretical,
and methodological issues hinder more widespread scientific acceptance and use in policy settings. Of particular concern is
how EFA is defined and what it actually measures, exclusion of open oceans and less productive lands from biocapacity accounts,
failure to allocate space for other species, use of agricultural productivity potential as the basis for equivalence factors
(EQF), how the global carbon budget is allocated, and failure to capture unsustainable use of aquatic or terrestrial ecosystems.
This article clarifies the definition of EFA and proposes several methodological and theoretical refinements. Our new approach
includes the entire surface of the Earth in biocapacity, allocates space for other species, changes the basis of EQF to net
primary productivity (NPP), reallocates the carbon budget, and reports carbon sequestration biocapacity. We apply the new
approach to footprint accounts for 138 countries and compare our results with output from the standard model. We find humanity’s
global footprint and ecological overshoot to be substantially greater, and suggest the new approach is an important step toward
making EFA a more accurate and meaningful sustainability assessment tool.
相似文献
Jason VenetoulisEmail: |