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391.
以天然矿物质沸石、细砂及煤渣取代传统滤料构建复合基质生态床,表面种植景观植物,采用下向流-上向流运行方式修复北方景观水体。分别进行静态实验及不同循环速率下的动态实验,考察对水体污染物去除过程。结果表明,2种运行方式下对水体NH+4-N去除率都在85%以上,其中以1 h为循环周期的运行方式去除率达97%,较静态提高12.8%;TN去除率最高为84%;TP去除不稳定,过程缓慢。煤渣层对NH+4-N的去除效果差,硝化作用不彻底与反硝化作用的加强使下层出水NH+4-N 、NO-2-N及NO-3-N浓度均高于上层。提高循环速率有利于对氮的去除。 相似文献
392.
Multi-criteria analysis via the VIKOR method for prioritizing land-use restraint strategies in the Tseng-Wen reservoir watershed 总被引:2,自引:0,他引:2
It is important to adopt proper water and soil conservation and land-use planning in a watershed for lowering adverse impacts on reservoir water quality. Although reservoir watersheds occupy a large amount of land in Taiwan, high population density has exerted development pressures on such land. Therefore, the priority ranking of land-use restrictions for the subdivisions with different degrees of environmental vulnerability is necessary in watershed management. Since there are several criteria for evaluating the potential environmental impact from the subdivisions, multi-criteria analysis was applied as a technique for solving these problems in this study. The VIKOR method was applied to determine the best feasible solution according to the selected criteria, including geographical and meteorological factors. The objective of this study was to establish the priority ranking of land-use restrictions in the Tseng-Wen reservoir wastershed in southern Taiwan. The results show that subdivisions close to the outlet or reservoir area should have the priority of land-use restrictions. 相似文献
393.
Allen CD 《Environmental management》2009,43(2):346-356
Characterized by expensive housing, high socioeconomic status, and topographic relief, Upper Sonoran Lifestyle communities
are found primarily along the Wildland-Urban Interface (WUI) in the Phoenix, Arizona metro area. Communities like these sprawl
into the wildlands in the United States Southwest, creating a distinct urban fringe. This article, through locational comparison,
introduces and evaluates a new field assessment tool for monitoring anthropogenic impact on soil–vegetation interactions along
the well-maintained multi-use recreational trails in Upper Sonoran Lifestyle region. Comparing data from randomly selected
transects along other multi-use trails with data from a control site revealed three key indicators of anthropogenic disturbances
on soil–vegetation interactions: soil disturbance, vegetation disturbance, and vegetation density. Soil and vegetation disturbance
displayed an average distance decay exponent factor of −0.60, while vegetation density displayed a reverse decay average of
0.60. Other important indicators of disturbance included vegetation type, biological soil crusts, and soil bulk density. The
predictive ability of this new field tool enhances its applicability, offering a powerful rapid ecological assessment method
for monitoring long-term anthropogenic impact in the Upper Sonoran Lifestyle, and other sprawling cities along the WUI. 相似文献
394.
395.
胡振鹏 《长江流域资源与环境》2009,18(7):664
规模养猪是专业化、集约化生产方式,也是农业产业化经营的发展趋势。如果养猪场产生的大量粪尿得不到妥善处置和充分利用,将对环境产生很大的危害。猪粪尿中含有大量的营养物质和生物质能,以猪粪尿厌氧发酵为纽带,充分利用沼液和沼渣作为发展种植业和渔业的肥料或饲料,形成“农林渔牧”生态农业体系,不仅有效促进农村经济发展、增加农民收入,而且能够保护生态环境、节约资源。剖析了小、中、大3类猪场以沼气建设为纽带发展生态农业的规律、生产模式、系统结构及其效果。结果表明,为了促进规模养猪健康发展,形成“农林渔牧”生态农业体系,养猪专业户必须增强节约资源、保护环境的社会责任感,政府要加强猪场污染物排放的监管,同时制定优惠政策引导和促进猪粪尿资源综合利用。 相似文献
396.
E. L. Zheleznaya 《Russian Journal of Ecology》2009,40(1):39-43
The overgrowing of meadow-bog communities by shrubs and trees (age 5–40 years, crown closure 0.4–0.9) leads to a decrease in incident illumination. As a consequence, juvenile and generative plants disappear from D. incarnata population loci, their average ecological density decreases, and the loci enter the state of regression. The digging activity of wild boars disrupts phytocenotically closed groups of longirhizomatous herbs, thereby creating favorable conditions for seed reproduction of D. incarnata. The species begins to form population loci with a complete ontogenetic spectrum and high ecological density, eventually restoring the normal (definitive) population structure. 相似文献
397.
A. P. Gusev 《Russian Journal of Ecology》2009,40(3):160-165
Specific features of progressive succession in the vegetation of anthropogenically transformed landscapes in southeastern Belarus have been studied in permanent test plots. Using phytoindication scales proposed by Ellenberg (1974) and Tsyganov (1983), trends of changes in ecological conditions in the first years of succession have been revealed. 相似文献
398.
Specific ecogenetic features of solods in the forest-steppe zone has been studied, and the role of biotic and abiotic factors of soil formation has been estimated. Differentiation of soil horizons with respect to the physical clay fraction accounts for specific features of their moistening, which is reflected in the ratio of strongly and weakly crystallized forms of iron. Periodic changes in redox conditions results in iron segregation, and a high content of fulvic acids accounts for its eluvial migration. These processes are controlled by soil geochemical barriers. 相似文献
399.
针对城市化进程加快引发的一系列环境污染问题,指出了加快污染防治设施社会化运营的必要性,并从污染治理设施的种类、污染治理设施的社会化运营分析和运作模式三方面论述了如何进行污染治理设施的社会化运营,从经济发展、污染防治设施运行、引入竞争机制等方面概述了污染防治设施社会化运营对区域环境与经济协调发展的影响。 相似文献
400.
本文以旅游景区的经营模式为研究核心,从现有国内外旅游景区组织结构分析入手,构建了适合我国国情和旅游景区可持续发展要求的两种经营模式:一种是国有国营的次国家公园模式,另一种是完全企业化经营,并且提出了两种模式运作的保障条件。 相似文献