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排序方式: 共有627条查询结果,搜索用时 31 毫秒
41.
用有机玻璃材料做成模拟人工湿地,分别种植芦苇和香蒲考察2种模拟植物湿地对城市污泥干化和稳定化、污泥中营养元素和重金属去除效果,并和空白湿地对比。实验污泥取自当地污水厂二沉池,污水处理采用厌氧池加氧化沟工艺。模拟人工湿地进泥负荷为0.72 kg TS/(m2.d),进泥中TS平均含量为5.58 g/L,pH为6.80。实验期为1年,采用间歇式进泥,渗滤液月采集测样一次,湿地剩余污泥2月1次。实验结果受天气和气候影响较大,处理效果夏季好于冬季,出水水质和剩余污泥的干化及稳定效果芦苇湿地好于香蒲湿地。剩余污泥中各种重金属含量低于污泥农用标准中各重金属离子浓度要求。结果表明,人工湿地植物净化系统对城市污泥有较好的脱水和稳定化效果。 相似文献
42.
杨婷 《再生资源与循环经济》2015,(7)
检索了微生物燃料电池在中国的发明专利文献,综述了微生物燃料电池在废水处理中的应用及与现有技术中其他水处理技术耦合的专利进展,并对其实际应用的前景进行了展望。 相似文献
43.
44.
Mannino I Franco D Piccioni E Favero L Mattiuzzo E Zanetto G 《Environmental management》2008,41(1):118-129
A cost-effectiveness analysis was performed to evaluate the competitiveness of seminatural Free Water Surface (FWS) wetlands
compared to traditional wastewater-treatment plants. Six scenarios of the service costs of three FWS wetlands and three different
wastewater-treatment plants based on active sludge processes were compared. The six scenarios were all equally effective in
their wastewater-treatment capacity. The service costs were estimated using real accounting data from an experimental wetland
and by means of a market survey. Some assumptions had to be made to perform the analysis. A reference wastewater situation
was established to solve the problem of the different levels of dilution that characterize the inflow water of the different
systems; the land purchase cost was excluded from the analysis, considering the use of public land as shared social services,
and an equal life span for both seminatural and traditional wastewater-treatment plants was set. The results suggest that
seminatural systems are competitive with traditional biotechnological systems, with an average service cost improvement of
2.1-fold to 8-fold, according to the specific solution and discount rate. The main improvement factor was the lower maintenance
cost of the seminatural systems, due to the self-regulating, low artificial energy inputs and the absence of waste to be disposed.
In this work, only the waste-treatment capacity of wetlands was considered as a parameter for the economic competitiveness
analysis. Other goods/services and environmental benefits provided by FWS wetlands were not considered.
相似文献
Daniel FrancoEmail: |
45.
青海湖几种主要湿地植物的种群分布格局及动态 总被引:25,自引:2,他引:23
应用种群生态空间分布的分析方法,研究了青海湖四种主要湿地植物:杉叶藻(Hippuris vulgaris)、槽杆荸荠(Eleocharis valleculosa)、华扁穗莞(Blysmus sinocompresus)、碱蓬(Suaeda glauca)的空间分布格局及其动态,研究表明:杉叶藻、槽杆荸荠、华扁穗莞三种群由侵入期、定期初期到种群发育盛期的过程中,其集群程度先增大后减小,总体呈扩散的趋势;碱蓬种群,从幼苗到繁殖期,集群程度增大,呈聚集的趋势,说明前三种植物的克隆繁殖方式于滨湖湿地生境具有更好的生态适应性,图2表3参11 相似文献
46.
对人工湿地污水处理工艺及其对水中污染物的去除机理进行了综述,并对人工湿地处理污水的技术进行了展望。 相似文献
47.
Long-Term Relationship between Phosphorus Inputs and Wetland Phosphorus Concentrations in a Northern Everglades Marsh 总被引:3,自引:0,他引:3
Assessments of long-term relationships between changes innutrient inputs and wetland nutrient concentrations can becomplicated by fluctuations in other environmental factors aswell as by problems typical of long-term monitoring data.Consequently, statistical analysisof these types of data sets requirescareful consideration of environmental covariates, potentialbiases in the monitoring design, and irregularities caused bychanges in field sampling protocols. We evaluated therelationship between anthropogenic phosphorus (P) inputs andwater-column total P (TP) concentrations in a northernEverglades marsh by statistically analyzing available datacollected from several sampling programs over the past 20 years(1978–1997). Canal inputs of agricultural runoff contributemost of the P to the marsh and have produced a zone ofenrichment within the marsh during the past few decades.Regression analyses showed that both canal and marsh TPconcentrations increased during the 1980s and then decreased inthe 1990s. However, the statistical relationship between canal Pinputs and marsh TP, while significant, generally was weakexcept for marsh locations adjacent to the canal. Strongerrelationships existed between marsh TP and hydrologic parameterssuch as marsh water depth, which is controlled by changes inweather patterns and marsh management. In particular, dryconditions during the 1980s may have contributed to observedincreases in marsh P concentrations and the movement of a P`front' further into the marsh. Higher rainfall and water depthsand agricultural best management programs initiated during the1990s have been associated with reduced P concentrations incanal waters entering the marsh. While it is anticipated thatthis reduction eventually will result in lower marsh TPconcentrations, this effect is not yet evident, possibly due tointernal loading of P from enriched marsh soils. Our findingsillustrate some of the environmental factors that can complicateattempts to develop empirical relationships between P inputs andwetland P concentrations and to use such relationships to forecast changesin marsh concentrations based on past monitoring data alone. 相似文献
48.
Thomas Carlisle George Mulamoottil Bruce Mitchell 《Journal of the American Water Resources Association》1991,27(3):419-427
ABSTRACT: The objective was to survey individuals from different interest groups in Ontario to ascertain attitudes towards the use of artificial wetlands for stormwater management and to provide waterfowl habitat. In total, 166 questionnaires were distributed and 124 cempleted returns were received. The results of the survey show that the provision of wetlands as waterfowl habitats in the context of stormwater impoundments is severely limited and is not considered an important management option. The overwhelming rejection of this integrated approach seems to be due to a lack of understanding and its comparative newness. Some of the perceived problems and concerns could be addressed by improvements in the design of the artificial wetlands. The design and implementation of an artificial wetland prototype as part of an education program in Ontario is recommended. A few research opportunities also are outlined. 相似文献
49.
The United States Soil Conservation Service (SCS) conducts a survey for the purpose of establishing an agricultural land use database. This survey is called the National Resources Inventory (NRI) database. The complex NRI land classification system, in conjunction with the quantitative information gathered by the survey, has numerous applications. The current paper uses the wetland area data gathered by the NRI in 1982 and 1987 to examine empirically the factors that generate wetland loss in the United States. The cross-section regression models listed here use the quantity of wetlands, the stock of drainage capital, the realty value of farmland and drainage costs to explain most of the cross-state variation in wetland loss rates. Wetlands preservation efforts by federal agencies assume that pecuniary economic factors play a decisive role in wetland drainage. The empirical models tested in the present paper validate this assumption. 相似文献
50.
ABSTRACT: Selected studies from the literature were reviewed to determine the extent of knowledge about the relationship between hydrology and wetland ecosystem studies. Wetland studies of chemical input-output relationships have been the most dependent on hydrologic data of all wetland investigations; yet, very few of these studies have attempted to measure all components of a wetland's water balance. Usually, unmeasured components were calculated as the difference between measured inputs and outputs. Ground water frequently was overlooked. Chemical input-output investigations primarily were concerned with determining the amount of input retained in the wetlands. Few studies also included direct measurement of biogeochemical processes within wetlands of elements that were part of simultaneous input-output investigations. The importance of uncertainties in chemical budgets that are due to uncertainties in hydrologic budgets has been addressed in very few wetland investigations. Although many studies have emphasized the importance of hydrology to wetland ecosystem research, few studies have documented this, so that hydrology remains one of the least understood components of wetland ecosystems. 相似文献