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1.
In order to assess the urban runoff control effectiveness of a low-impact development best management practice (LID-BMP) treatment train system, a field test of selected LID-BMPs was conducted in China. The LID-BMPs selected include three grassed swales, a buffer strip, a bioretention cell, two infiltration pits, and a constructed wetland. The test site is in a campus in southern China. The LID-BMPs, connected in a series, received stormwater runoff from four tennis courts with an area of 2808 m2 and eight basketball courts with an area of 4864 m2. Construction of the LID-BMPs was completed in early spring of 2012, and the sampling was conducted during May of 2012 to September of 2013. During the sampling effort, besides the performance evaluations of grassed swales and the bioretention cell in controlling runoff quantity as well as quality, the emphasis was also on determining the performance of the LID-BMP treatment train system. A total of 19 storm events were monitored, with nine producing no runoff and ten producing runoff. Data collected from the ten storm events were analyzed for estimating runoff quantity (peak flow rate and total runoff volume) and quality reduction by the LID-BMPs. The sum of loads (SOL) method was used for calculating the water quality performance of LID-BMPs. Results indicated that, for peak flow rate, a bioretention cell reduction of 50–84 % was obtained, and grassed swale reduction was 17–79 %, with a runoff volume reduction of 47–80 and 9–74 %, respectively. For water quality, the bioretention cell in general showed good removal for zinc (nearly 100 %), copper (69 %), NH3-N (ammonia nitrogen) (51 %), and total nitrogen (TN) (49 %); fair removal for chemical oxygen demand (COD) (18 %); and poor removal for total suspended solids (TSS) (?11 %) and total phosphorus (TP) (?21 %). And its performance effectiveness for pollutant removal increased in the second year after 1 year of stabilizing. When considering the aggregated effect of the LID-BMP treatment train system, it showed excellent removal for NH3-N (73 %), TN (74 %), and TP (95 %) and fair removal for COD (19 %) and TSS (35 %). The assessment results of the LID-BMP treatment train system provide valuable information on how to link the different types of LID-BMP facilities and maximize the integrated effectiveness on urban runoff control.  相似文献   

2.
Development of groundwater quality index   总被引:1,自引:0,他引:1  
Assessing the water quality status for special use is the main objective of any water quality monitoring studies. The water quality index (WQI) is a mathematical instrument used to transform large quantities of water quality data into a single number which represents the water quality level. In fact, developing WQI in an area is a fundamental process in the planning of land use and water resources management. In this study, a simple methodology based on multivariate analysis is developed to create a groundwater quality index (GWQI), with the aim of identifying places with best quality for drinking within the Qazvin province, west central of Iran. The methodology is based on the definition of GWQI using average value of eight cation and anion parameters for 163 wells during a 3-year period. The proportion of observed concentrations to the maximum allowable concentration is calculated as normalized value of each parameter in observing wells. Final indices for each well are calculated considering weight of each parameter. In order to assess the groundwater quality of study area, the derived indices are compared with those of well-known mineral waters. Using developed indices, groundwater iso-index map for study area and the map of areas of which the indices are near to mineral waters was drawn. In the case study, the GWQI map reveals that groundwater quality in two areas is extremely near to mineral water quality. Created index map provides a comprehensive picture of easily interpretable for regional decision makers for better planning and management.  相似文献   

3.
The Korean government recently proposed expanding the number of soil-quality standards to 30 by 2015. The objectives of our study were to construct a reasonable protocol for screening priority soil contaminants for inclusion in the planned soil quality standard expansion. The chemical ranking system of soil pollution substances (CROSS) was first developed to serve as an analytical tool in chemical scoring and ranking of possible soil pollution substances. CROSS incorporates important parameters commonly used in several previous chemical ranking and scoring systems and the new soil pollution parameters. CROSS uses soil-related parameters in its algorithm, including information related to the soil environment, such as soil ecotoxicological data, the soil toxic release inventory (TRI), and soil partitioning coefficients. Soil TRI and monitoring data were incorporated as local specific parameters. In addition, CROSS scores the transportability of chemicals in soil because soil contamination may result in groundwater contamination. Dermal toxicity was used in CROSS only to consider contact with soil. CROSS uses a certainty score to incorporate data uncertainty. CROSS scores the importance of each candidate substance and assigns rankings on the basis of total scores. Cadmium was the most highly ranked. Generally, metals were ranked higher than other substances. Pentachlorophenol, phenol, dieldrin, and methyl tert-butyl ether were ranked the highest among chlorinated compounds, aromatic compounds, pesticides, and others, respectively. The priority substance list generated from CROSS will be used in selecting substances for possible inclusion in the Korean soil quality standard expansion; it will also provide important information for designing a soil-environment management scheme.  相似文献   

4.
The combination of intensive agricultural activities and the close connectivity between land and stream emphasise the potential risk of pesticide exposure in Danish streams. Benthic macroinvertebrates are applied in the assessment of stream ecological status, and some sensitive species have been shown to respond strongly to brief pulses of pesticide contamination. In this study we investigate the impact of agriculturally derived pesticides on stream macroinvertebrate communities in Denmark. As a measure of toxic pressure we apply the Runoff Potential. We investigated a total of 212 streams. These were grouped into distinct classes according to the magnitude of pesticide contamination in the period from 2003-2006. A total of 24 different macroinvertebrate indices were applied to detect effects of pesticide runoff (e.g. the SPEAR-index and the number of EPT taxa). We found high predicted pesticide runoff in 39% of the streams, but we found no significant effect of predicted pesticide exposure on stream macroinvertebrate indices. We, additionally, examined the influence of a series of environmental parameters ranging from site scale to catchment scale on the macroinvertebrate community. Relative proportions of gravel, sand and silt in bed sediments explained most of the variation in macroinvertebrate indices as well as the upstream riparian habitat quality. We suggest that the Runoff Potential model overestimate pesticide runoff contamination in Danish streams due the presence of buffer strips enforced by Danish legislation. When pesticide runoff contamination is low to moderate, poor physical properties (indirectly related to agricultural activity) are the main impediment for the ecological quality of Danish streams.  相似文献   

5.
Solar PV systems are being installed in airports across the globe. It is a relatively new application of solar PV technology with a potential impact on aviation safety. The main objective of this paper is to assess the risk of solar photovoltaics at the airport. At first, potential risk/ hazard to aviation safety from solar photovoltaics in airport premises is identified, and then the severity and probability level for each risk is assessed. A risk assessment matrix is developed using Hazard Identification and Risk Assessment method. It is observed that there are seven types of possible hazards from airport-based solar PV systems. The risk index is highest for glare occurrence from PV modules (4B), strike from birds in PV site (4B), and interference to communication systems (3B). It is concluded that most of the risks need implementation of mitigation measures such as prior glare assessment in the feasible sites, periodic monitoring of bird's activity in the PV array and follow safety distance between PV array and communication aids. Researchers and engineers must work along with aviation and airport officials to mitigate possible risks from solar PV installation in the airports.  相似文献   

6.
7.
Sustainability indicators are increasingly recognized as a useful tool to provide policy information in support of environmental, economic or social improvement. Various approaches to sustainability have also been adopted in universities through the introduction of specific rankings. International rankings are an important communication tool that allows the comparison of universities according to combinations of different appropriately weighed parameters. The GreenMetric World University Ranking is the only worldwide ranking of universities that compares environmental sustainability across various campuses. It uses indicators involving education, research and the environment to evaluate the measures undertaken by universities to develop ecological infrastructures and stimulate improvement. The aim of this work is to analyze the individual indicators and categories used in the GreenMetric ranking in detail to verify whether they are, in fact, useful in assessing the sustainability of universities. Through the implementation of the cluster analysis, based on a selection of identified variables, all campuses were classified in homogeneous groups. The results identify four levels of sustainability and show a strong relationship between the rankings of the different categories (setting and infrastructure, energy and climate change, transportation, waste and water conservation and recycling) and specific aspects for assessing institutional policies. These results are useful information to guide universities in the research of key issues on where to invest time and resources to improve the sustainability of their structures and, therefore, their attractiveness.  相似文献   

8.
There has been much recent research on site selection for species preservation, although most of this research has focused on terrestrial plant and animal species. There is increasing evidence that lack of suitable habitat for migratory birds is contributing to their diminishing numbers. We extend the literature of site selection with a specific application to migratory birds. We develop reserve planning models, based on the novel idea of Directed Conditional Covering, to identify superior configurations of locations to be included in migratory flyways.  相似文献   

9.
层次分析赋权法在城市空气质量排名中的应用   总被引:2,自引:1,他引:1  
通过对空气质量排名中常用的综合指数法的优缺点进行分析,提出了一种基于层次分析法的加权综合指数排名方法,根据每种污染物的重要性不同,赋予各污染物相应的权重,进行了城市间排名测算分析。结果表明,加权综合指数法兼顾了各项污染物对空气质量的贡献,又能够重点突出主要污染物的贡献,各城市间可比性强,能够客观、准确、公平地反映不同城市间空气质量状况差异,能满足当前中国城市环境空气质量排名工作的需要。  相似文献   

10.
Anthropogenic eutrophication of aquatic ecosystems continues to be one of the major environmental issues worldwide and also of Brazil. Over the last five decades, several approaches have been proposed to discern the trophic state and the natural and cultural processes involved in eutrophication, including the multi-parameter Assessment of Estuarine Trophic Status (ASSETS) index model. This study applies ASSETS to four Brazilian lagoons (Mundaú, Manguaba, Guarapina, and Piratininga) and one estuarine delta (Paraíba do Sul River), set along the eastern Brazilian coast. The model combines three indices based on the pressure–state–response (PSR) approach to rank the trophic status and forecast the potential eutrophication of a system, to which a final ASSETS grade is established. The lagoons were classified as being eutrophic and highly susceptible to eutrophication, due primarily to their longer residence times but also their high nutrient input index. ASSETS classified the estuary of the Paraíba do Sul river with a low to moderate trophic state (e.g., largely mesotrophic) and low susceptibility to eutrophication. Its nutrient input index was high, but the natural high dilution and flushing potential driven by river flow mitigated the susceptibility to eutrophication. Eutrophication forecasting provided more favorable trends for the Mundaú and Manguaba lagoons and the Paraíba do Sul estuary, in view of the larger investments in wastewater treatment and remediation plans. The final ASSETS ranking system established the lagoons of Mundaú as “moderate,” Manguaba as “bad,” Guarapina as “poor,” and Piratininga as “bad,” whereas the Paraíba do Sul River Estuary was “good.”  相似文献   

11.
Site index for jack pine, black spruce and trembling aspen was found to be poorly related to soil types described in the Northwestern Ontario Forest Ecosystem Classification (NWO FEC). Statistical analyses showed that average site indices for most soil types and groupings of soil types were not significantly different from each other.Site index varies greatly within presently defined NWO FEC soil types because certain soil and topographic features that are closely related to site index vary greatly within soil types or are not well described by the NWO FEC soil types. These critical soil features have been identified by soil-site studies that show features most closely related to site index usually are surface soil features found within the effective rooting zone of forest trees. These critical features include depth to bedrock, depth to root restricting soil layers, and coarse fragment content and texture of surface soil horizons.Site-quality research in Northwestern Ontario is closely integrated with the NWO FEC program, thus future NWO FEC soil classifications probably will use results from our soil-site research as a basis for soil type revisions. The result will be future soil types that are more closely related to forest site quality and thus to the capability of forest land to produce tree growth.  相似文献   

12.
Hydrological responses and pollutant exports are always highly related to rainfall characteristics. Many studies have demonstrated that the influence of moving rainstorm on flows and mass transport process in hydrologic systems cannot be ignored. Best management practices (BMPs) are popularly applied for controlling water quantity and water quality in a watershed. Since the movements of rainstorm can influence watershed responses, BMP placement strategies should be suitably adjusted in different moving rainstorms. This study designed an intermediate rainfall pattern with varied movement behavior and tried to find the optimal BMP placement strategies, which cannot only satisfy environmental standards but also improve economic benefits, for the rainfall events. The result shows that the control efficiency of pollutant and runoff can highly improve when the BMPs are set near the outlet of a watershed. Since the economic efficiency is always regarded as an important factor, the BMP placement strategy is significant for watershed conservation and management.  相似文献   

13.
以长沙某河库兼用型饮用水水源地一、二级保护区土壤为研究对象,于2018年8月采用网格布点法在一级和二级保护区分别布设3个和7个采样点,在水源地历史采样区布设5个采样点,探究土壤中Cd、Pb、Cr、Cu、Zn、Ni、Hg、As的含量分布及污染水平。结果表明:土壤中As、Cd、Cr、Cu、Hg、Ni、Pb、Zn的含量均值分别为46.56、4.90、81.87、46.64、0.19、30.11、75.11、237.93 mg/kg。重金属元素含量均值超过农用地污染风险筛选值的样品占比排序为Cd (86.7%)>Zn (60%)>As (53.3%)>Cu (6.7%)=Pb (6.7%)。土壤中As、Cd、Cr、Cu、Hg、Ni、Pb、Zn的单因子污染指数分别为1.55、16.34、0.41、0.47、0.08、0.30、0.63、0.95,主要为Cd、As污染。研究区土壤重金属综合污染指数为11.71,属重污染等级。水源地一级保护区、二级保护区、历史采样区2018年、历史采样区2014年土壤重金属综合污染指数分别为20.41、14.94、1.98、1.17。后期应加强对该饮用水水源地土壤中Cd、Pb、Cu、Zn、As的污染控制和治理。  相似文献   

14.
Applying Fuzzy logic and the point count system to select landfill sites   总被引:1,自引:0,他引:1  
The treatment of solid waste is currently one of the major environmental problems facing municipalities. Thousands of tonnes of waste are generated each day, requiring a large area for disposal purposes. It is difficult to find suitable areas for the construction of such sanitary landfills as numerous criteria must be met, and landfill sites vary considerably in terms of their sophistication. The selection criteria for landfill sites should be as simple as possible, and with this in mind, we have evaluated a large number of random cases for the suitability of the site for landfill purposes using the recently advocated fuzzy approach. Using the fuzzy classification, we have attempted to develop a simple classification which uses only certain point values for available attributes. A normalized average of such attributes based on the proposed classifier is further evaluated using additionally generated random data sets. The results appear to be encouraging and indicate that the present classifier can be used as a substitute for the fuzzy-based ranking of landfill sites.  相似文献   

15.
It is planned that the Dayanghan Wetland in China will be transformed into a national park but little is known about its current water quality and pollution status. Thus, we monitored the physical and chemical characteristics of the Dayanghan Wetland, which showed that the water quality was generally good. However, the chemical oxygen demand was more than double the reference value, which may be attributable to previous tillage for vegetable crops and other farmlands. In addition, nickel and chromium caused low-level pollution in the water bodies of the Dayanghan Wetland. The mean trophic level index and nutrient quality index were 39.1 and 2.69, respectively. Both indices suggest that the water bodies of the Dayanghan Wetland are in a mesotrophic state and that no eutrophication has occurred. The study would provide a precise report on the status of environmental quality of the water bodies of a typical pre-construction wetland for the administration and decision of the local government and the planning agent.  相似文献   

16.
The diatom community was studied in 110 sites within the Guadalquivir River catchment area, South Spain, in order to test the applicability of diatom biotic indices developed in other European regions to this site and to provide a useful tool for monitoring water quality in the river basin. We identified 399 taxa and calculated five diatomic indices (Specific Polluosensitivity Index (IPS), Biological Diatom Index, Trophic Diatom Index, Index of the European Economic Community, and Diatom-based Eutrophication Pollution Index (EPI-D)). Since the indices analyzed were highly correlated, their results could be compared. The indices that gave the best results were the EPI-D followed by the IPS, the latter being the most widely used index in Iberian catchments. Nevertheless, the EPI-D presented certain advantages: (1) this index correlated the best with the water chemistry in the catchment area; (2) EPI-D is not sensitive to the presence of taxa belonging to the Achnanthidium minutissimum complex frequently present in the Guadalquivir basin. Nevertheless, EPI-D retains its effectiveness and thus constitutes an easier index for application from a taxonomical standpoint. We estimated the general water quality of the entire basin on the basis of EPI-D. According to these results, 55% of the sites had either high or good water quality. The species that better characterized each water quality category in the study area were: A. minutissimum (high and good), Amphora pediculus (moderate), Nitzschia frustulum (poor), and Nitzschia capitellata (bad).  相似文献   

17.
论开展主要环境质量指标浓度考核   总被引:1,自引:1,他引:0  
针对现行环境质量考核体系中存在问题,选取主要的环境质量考核指标,提出逐步推行浓度值考核设想,并对比分析该考核办法与现行比例考核办法的优劣。  相似文献   

18.
Water pollution from point sources has been considerably reduced over the last few decades. Nevertheless, some water quality problems remain, which can be attributed to non-point pollution sources, and in particular to agriculture. In this paper the results of a study intended to assess the consequences, in terms of NO3 water pollution, of growing a crop, whose impact in terms of P pollution is already well known, are presented. The potential consequences, in terms of water pollution from nitrates of a BMP expressly applied to reduce P pollution are also discussed. The study site is the Lake Vico basin, Central Italy, which has suffered a shift in trophic state since the mid 1990s, caused by P compounds used for intensive cultivation of hazelnut trees. The results of the monitoring campaign described in this paper allow to assert that hazelnut tree cropping has probably caused a considerable increase in nitrate concentration in the groundwater, although not in the lake water, because of the specific hydrogeological characteristics of the basin. The main conclusion is that monitoring is essential to single out environmental characteristics peculiar of a specific area, which even the most sophisticated model would not have been able to highlight. This is why monitoring and model simulations should be integrated.  相似文献   

19.
为了探讨2009年入秋至2010年春,西南百年一遇大旱后城市降雨径流中重金属污染特性,对昆明市交通干道路面及路旁一处混凝土屋面的3次降雨径流进行了监测,研究了城区降雨径流中Cu、Zn、Cd、Pb、Fe、Mn、Cr的变化过程,分析了不同重金属之间、重金属与悬浮物(SS)之间的相关性。3次降雨径流中重金属质量浓度随降雨呈不同程度下降。大旱后的首次降雨径流重金属污染最严重,次日的降雨径流重金属污染最轻。降雨径流中各重金属均与SS在含量上明显相关,径流中的重金属主要以吸附在SS上的不溶态存在。屋面与路面径流中的大多数重金属具有良好的同源性。  相似文献   

20.
秦成  刘浩  刘念 《中国环境监测》2019,35(2):136-141
为建立和量化适于河流水质自动监测站选址的评价方法体系,提出了河流水质自动监测站选址一致性、可行性和适宜性评价问题,并建立了选址可行性和适宜性评价2套指标体系。以自动站选址与手工断面位置不一致为前提,利用累乘指数判断选址可行性,在可行的基础上利用模糊综合评价进一步分析选址的适宜性。应用案例显示,罗汉大桥断面水质自动站选址于手工断面下游150 m处是可行的,并且此选址高度适宜,在具有水质代表性的同时兼顾成本和运维管理需求。  相似文献   

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