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131.
悬挂链曝气技术应用于河流污染治理   总被引:7,自引:0,他引:7  
在介绍了悬挂链曝气技术的特点和在复氧曝气方面的适用性的基础上,对该技术的局限性进行了阐述,并认为悬挂链技术为河流污染治理提供了一种新选择。  相似文献   
132.
海岸带生态恢复技术研究现状及存在问题   总被引:8,自引:0,他引:8  
气候及其潜在的全球性变化所带来的影响,使海岸带受到严重威胁,人口的增加以及人类活动强度的增大给海岸带环境带来的负面影响越来越严重,对目前国内外海岸带生态恢复技术的现状作了较系统地介绍,并阐述了当前海岸带生态恢复中存在的主要问题。  相似文献   
133.
《Ecological modelling》2003,170(2-3):245
With the increasing importance and awareness of water quality in the small basins, the modelling system is developed for monitoring and predictions of surface water pollution. The compartment model deals with basin characteristics extended by land cover attributes. The parameters of the model are estimated by experimental data of water quality together with land cover types that serve as nutrient detention media or transformers. The study examines methodology to determine the potential areas of nitrate pollution from point and non-point sources by remote sensing techniques. Classification of water, agricultural, forest and urban areas is processed with satellite images (LANDSAT 7). Whereas the agricultural and urban areas act as sources of pollution, forest zones operate as sinks. The nitrate levels are decreased downstream, if the proportion of the forest inside contribution zones increases. The modelling system is used to simulate amounts of nitrates in each compartment of the stream during the monitored period of one year. The number of compartments and their lengths are estimated on the basis of morphology of the basin. Simulation of the dynamic model is carried out with the TabSim. Geographic information system (GIS) and remote sensing tools are used to manage and estimate nitrate inflows from point and non-point sources of pollution. The article presents the spatial and time variation of the nitrate (NO3) within the basin of the stream Rakovnický (the west part of Bohemia, the whole area of 368 km2). It is shown that the model approach extended by the GIS and remote sensing can support decision-making process for better management practices in the basins.  相似文献   
134.
Variation in the endospermal protein patterns of seeds amongst and between inland and coastal populations of the dune building grassLeymus arenarius was examined in Iceland. Seeds were collected from six coastal populations and five inland populations in Iceland. Endospermal proteins (prolamins) of seeds were extracted with Tris-buffered 2-propanol (50%) and β-mercaptoethanol (0.5% v/v). We used 8% and 12% sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) to separate the prolamin protein bands, which were stained with Coomassie Brilliant Blue R. Coastal populations were differentiated from inland populations on the basis of high frequency of high molar weight (HMW) (110–150 kg mol−1) prolamins. Coastal populations had significantly higher proportions of their seed with more than two HMW prolamins, than those of inland populations. Subtle differences were found among the HMW prolamins of coastal and inland populations indicating limited intrapopulation variation. The dynamic environment of sand dunes probably influences the genetic composition of these populations. The results suggest that seeds of the inland and coastal populations should be treated separately in sand dune reclamation and restoration works  相似文献   
135.
武汉莲花湖是典型的富营养化城市浅水湖泊.通过对其进行16mo的监测后发现,治理后的小莲花湖比大莲花湖水质有明显改善.监测期间小莲花湖底栖动物密度和生物量均值明显高于大莲花湖,Shannon多样性指数与Margalef多样性指数也高于大莲花湖.将大、小莲花湖的10种环境因子和底栖动物密度进行典型相关分析后,发现总磷、温度、总氮、叶绿素a、氨离子是对底栖动物群落具有显著性影响的环境因子.图8表3参20.  相似文献   
136.
137.
We measured denitrification at 15 sites during 1 year in a agricultural catchment in Brittany, France. Our objective was to assess the relative importance of heterotrophic denitrification on the fate of excess nitrogen at the catchment scale, and to quantify the relative importance of riparian areas on the N2O emissions. Using the C2H2 inhibition technique, denitrification rate on soil core and denitrifying enzyme activity (DEA) were each determined, for samples taken from two soil layers: 0–20 and 20–40 cm. Denitrification rates, ranging from 0 to 417 mg N m−2 d−1, were significantly higher in riparian areas than for hillslopes (median of 24.87 against 10.38 mg N m−2 d−1). However, since denitrification rates are significant in the hillslope and given that hillslope surface area is much greater (79% of catchment surface), this domain could be responsible for half of the overall denitrified nitrogen (N). Also, the 20–40 cm deep soil layer was found to account for more than 46% of the denitrification. The DEA indicates the potential for denitrifying activity by the soil under non-limiting conditions, measured values ranged from 76.48 to 530.63 ng N g−1 dry soil h−1. The ratio N2O/(N2O + N2) was about 60% with no clear spatial or temporal trends. Soil moisture appeared to be the main limiting factor for denitrification at the field scale. The results suggest that, for this catchment, denitrification is a major route for nitrogen removal, but a significant proportion of this removal occurs as N2O.  相似文献   
138.
在实验室恒流--修复微生态系统中,通过健康水体来对武汉东湖污染程度不同的水体进行持续替换,以模拟受不同程度污染胁迫的自然水体恢复过程,其间定期测定微型生物群落的中结构和功能参数,通过其变动机制和规律,再现修复过程中微型生物群落的演替过程,并从生态学角度提出了东湖5个受到不同程度污染水体得到修复的换水库。  相似文献   
139.
滇池水华综合控制对策探讨   总被引:12,自引:0,他引:12  
水华污染已成为滇池目前面临的主要环境问题,滇池水华治理被国家列为重中之重的项目而予以高度重视,据多年的监测资料,滇池水华的各类主要是蓝藻门的微囊藻,其次为束丝藻和鱼腥藻。该文从多方面分析了滇池水华泛滥的原因,在此基础上提出了滇池水华控制和富营养化治理的综合对策,特别强调了滇池水华必须坚持控制污染源与生态修复相结合的原则。  相似文献   
140.
新时期国土空间生态修复的核心是整体保护与系统治理,强调生态保护修复与社会经济发展耦合关联的系统性、协同性。景观生态学以景观为研究对象,基于整体综合视角聚焦景观结构与功能演变及其与人类社会相互作用机理,重点关注过程耦合与空间集成。面向国土空间生态修复的战略需求,景观生态学“格局与过程耦合-时空尺度-生态系统服务-景观可持续性”的研究路径能够为国土空间生态修复提供重要学科支撑;依据格局-过程互馈机理识别退化、受损的山水林田湖草生命共同体,基于景观多功能性权衡协调社会-生态需求并确定修复目标,应用生态安全格局优化多层级修复网络体系,建立面向景观可持续性的多尺度级联福祉保障。  相似文献   
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