IMPACTS OF SURFACE DRAINAGE ON GROUND WATER HYDRAULICS1

ABSTRACT: The current dredge and fill practices in locating canals along the periphery of wetlands in south Florida are transforming natural basins that originally had primarily slower subsurface drainage to ones that discharge larger quantities of water faster, via a surface drainage system. The objective of this paper is to develop an analytical technique and a numerical model in quantifying the difference of surface and subsurface runoff before and after the construction of drainage canals, and for delineating the effects of drains on channel level and regional water tables in adjacent areas in south Florida. The surface runoff model is formulated on the climatic water balance technique, and the ground water model is treated as a one dimensional transient phenomenon that forms a nonlinear flow problem. Analytical solutions are derived through problem linearization. These two models are coupled to estimate the impact of drainage canals on the adjacent water table drawdown.     

Poldering vs compartmentalization: The choice of flood control techniques in Bangladesh

The choice of flood control techniques in Bangladesh is reviewed in the context of a case study on the impact of a small-scale polder, the Dhaka-Narayanganj-Demra (DND) Project. The results of a questionnaire survey among the urban floodplain residents, who have settled inside the polder and a control population from outside the polder, indicate that the project has achieved significant flood alleviation but has also induced considerable environmental degradation due to stagnation of water within the enclosed embankment. The project also experienced numerous problems of structural instability of embankments during major flood events. An attempt is made to extrapolate some of these adverse environmental impacts of the polder to the compartmentalization scheme, which has been proposed by a UNDP-sponsored Flood Policy Study as an innovative technique for floodplain management in Bangladesh. The findings of the study, however, do not provide an adequate basis for assessing viability of the proposed compartmentalization scheme. Nonetheless, the study illustrates the usefulness of questionnaire surveys among floodplain residents for obtaining data for project evaluation.     

Women's Awareness of and Attitudes Towards the Flood Action Plan (FAP) of Bangladesh: A Comparative Study

/ Bangladesh has recently tested a program called the Flood Action Plan (FAP) to solve its chronic flood problem. The FAP envisages that all the major rivers of Bangladesh will eventually be embanked on both sides in order to prevent flooding. This paper reports on the responses of rural women to the possible impacts of the proposed embankment projects as outlined in the FAP. A further attempt is also made to compare their responses with the results of an earlier survey conducted among male respondents. Data for this study were collected from two rural areas of Bangladesh. It shows that almost all respondents had heard about the proposed construction and that they overwhelmingly support the embankment project of the FAP. Respondents are also aware of both positive and negative impacts of embankment construction. Similar findings were also reported by a previous study dealing with male responses to the embankment project. KEY WORDS: Flood Action Plan; Bangladesh; Women     

SUITABILITY ANALYSIS FOR SELECTION OF PIPELINE ROUTES1

ABSTRACT: A brief review of environmental assessment methods is presented as an introduction to a study of environmental management problems in a coastal area of southern Louisiana. The assessment method used in the study is called suitability analysis and involves the use of matrices. The matrix approach is simply a convenient method for organizing all factors representing environmental concerns in a region. The matrices proved to be very useful in defining the present state of an environmental regime and in maintaining an inventory of regional features and potential impacts. The method is described in detail and illustrated by evaluating the potential impacts of a major pipeline construction job in the area. Of major concern is the potential impact on the water resources of the region. Disruption to the natural drainage could be detremental, and affect the suitability of available water for a given use. Limitations of the method are discussed and potential areas for improvement and research are noted. Coupled with an economic assessment, the suitability analysis method should prove beneficial for selecting development sites for industries, residential areas, and other construction activities.     

The acceptability, personal outcome expectations, and expected effects of transport pricing policies

Acceptability and personal outcome expectations (i.e., the extent to which one expects to be better or worse off) of transport pricing policies were examined in relation to the expected effects of these policies on one’s own car use, congestion and environmental problems. Car users who commuted frequently by car and experienced congestion on a regular basis evaluated two pricing measures, which were mainly aimed at either decreasing congestion (by tolling at congested areas) or environmental problems (by a differential kilometre charge based on car mass). For the policy mainly aimed to reduce congestion, acceptability was higher and personal outcome expectations were more positive when respondents expected reductions in congestion when the policy was implemented. The policy aimed to reduce environmental problems was more acceptable and respondents expected to be better off in general when they expected reductions in environmental problems after its implementation. Expectations, both about a decrease in congestion and environmental problems were related to respondents’ personal outcome expectations of the policy mainly aimed to decrease environmental problems. We conclude that the acceptability of transport pricing policies are not necessarily low because car users expect negative effects on their car use, but rather because they are not be convinced that transport pricing policies will reduce congestion and environmental problems.     

PUBLIC PERCEPTIONS OF WATER QUALITY IN A METROPOLITAN AREA1

ABSTRACT: A survey of public-perception of water quality problems in the Atlanta, Georgia metropolitan area was undertaken in 1970, using a 1594 case probability sample of households in Fulton and DeKalb Counties. The survey showed that 2/3 of the population considered water quality problems serious or critical, and 56 percent thought they were getting worse. A stronger enforcement role for the State and increased expenditures for improved treatment facilities were favored by 3/4 of the population. Both industries and municipalities were considered major contributors to water pollution. Those most familiar with the water quality situation considered the problem more serious and getting worse than did the remainder of the population. Perceptual variables were far more important as explanatory factors than were any demographic variables.     

Made in conflict. Local residents' construction of a local environmental problem

The aim of this paper is to understand how local residents participate in the construction of local environmental problems and to evaluate a particular analytical approach in environmental sociology to study this phenomenon. The paper is based on an interview study with a sample of local residents. The analysis demonstrates how the local residents attempt to construct a local environmental problem. In particular, the study focuses on how involved actors are positioned, how different sorts of knowledge claims are used, and how the neglect the residents perceive from the authorities affects the attempt to construct a local environmental problem. The study shows that the local residents play a central role in the construction of the situation and that the evaluated model could be very helpful as an analytical tool in the investigation of local residents' participation in the construction of environmental problems.     

Water quality and restoration in a coastal subdivision stormwater pond

Stormwater ponds are commonly used in residential and commercial areas to control flooding. The accumulation of urban contaminants in stormwater ponds can lead to a number of water quality problems including high nutrient, chemical contaminant, and bacterial levels. This study examined the interaction between land use and coastal pond water quality in a South Carolina residential subdivision pond. Eutrophic levels of chlorophyll and phosphorus were present in all seasons. Harmful cyanobacterial blooms were prevalent during the summer months. Microcystin toxin and fecal coliform bacteria levels were measured that exceeded health and safety standards. Low concentrations of herbicides (atrazine and 2,4-D) were also detected during summer months. Drainage from the stormwater pond may transport contaminants into the adjacent tidal creek and estuary. A survey of residents within the pond's watershed indicated poor pet waste management and frequent use of fertilizers and pesticides as possible contamination sources. Educational and outreach activities were provided to community members to create an awareness of the water quality conditions in the pond. Pond management strategies were then recommended, and selected mitigation actions were implemented. Water quality problems identified in this study have been observed in other coastal stormwater ponds of varying size and salinity, leading this project to serve as a potential model for coastal stormwater pond management.     

Use of Microbial Community to Evaluate Performance of a Wetland System in Treating Pb/Zn Mine Drainage

The performance of a wetland system in treating lead (Pb)/zinc (Zn) mine drainage was evaluated by using the polyurethane foam unit (PFU) microbial community (method), which has been adopted by China as a standardized procedure for monitoring water quality. The wetland system consisted of four cells with three dominant plants: Typha latifolia, Phragmites australis and Paspalum distichum. Physicochemical characteristics [pH, EC, content of total suspended solid (TSS) and metals (Pb, Zn, Cd, and Cu)] and PFU microbial community in water samples had been investigated from seven sampling sites. The results indicated that the concentrations of Pb, Zn, Cd, Cu, and TSS in the mine drainage were gradually reduced from the inlet to the outlet of the wetland system and 99%, 98%, 75%, 83%, and 68% of these metals and TSS respectively, had been reduced in concentration after the drainage passed through the wetland system. A total of 105 protozoan species were identified, the number of protozoa species and the diversity index (DI) gradually increased, while the heterotrophic index (HI) gradually decreased from the inlet to the outlet of the wetland system. The results indicated that DI, HI, and total number species of protozoa could be used as biological indicators indicating the improvement of water quality.     

Ecological Impacts of Revegetation and Management Practices of Ski Slopes in Northern Finland

Outdoor recreation and nature-based tourism represent an increasingly intensive form of land use that has considerable impacts on native ecosystems. The aim of this paper is to investigate how revegetation and management of ski runs influence soil nutrients, vegetation characteristics, and the possible invasion of nonnative plant species used in revegetation into native ecosystems. A soil and vegetation survey at ski runs and nearby forests, and a factorial experiment simulating ski run construction and management (factors: soil removal, fertilization, and seed sowing) were conducted at Ruka ski resort, in northern Finland, during 2003–2008. According to the survey, management practices had caused considerable changes in the vegetation structure and increased soil nutrient concentrations, pH, and conductivity on the ski runs relative to nearby forests. Seed mixture species sown during the revegetation of ski runs had not spread to adjacent forests. The experimental study showed that the germination of seed mixture species was favored by treatments simulating the management of ski runs, but none of them could eventually establish in the study forest. As nutrient leaching causes both environmental deterioration and changes in vegetation structure, it may eventually pose a greater environmental risk than the spread of seed mixture species alone. Machine grading and fertilization, which have the most drastic effects on soils and vegetation, should, therefore, be minimized when constructing and managing ski runs.     

WATER BUDGET ANALYSIS FOR THE EVERGLADES AGRICULTURAL AREA DRAINAGE BASIN1

ABSTRACT: Water budget studies are essential for water resources and environmental management. In this study, a water budget analysis is presented for the Everglades Agricultural Area (EAA) in South Florida for the period from 1973 to 1991. The EAA is a highly productive irrigation/drainage basin that has a high water table and organic soils. Water quality problems are associated with the drainage discharge from the basin. During dry periods, supplemental water is used for irrigation and in rainy periods excess water with relatively higher phosphorus content is pumped out of the basin to Lake Okeechobee and the Everglades ecosystem. Elevated concentrations of phosphorus in the runoff/drainage that is discharged from the EAA basin have created water quality problems. The mean surface water inflow to the basin was 63,990 ha-m, and the outflow was 131,447 ha-m per year. On the average, supplemental surface water use was 47,411 ha-m, and runoff/drainage was 114,816 ha-m per year. The mean annual basin rainfall was 120.9 cm. A general trend in the decline of the wet season rainfall is observed.     

AN APPLICATION OF THE ANALYTIC ELEMENT METHOD IN MODELING FLORIDA EVERGLADES HYDROLOGY1

ABSTRACT: The large volumes of ground water that are discharged from the Everglades toward the Miami metropolitan area have historically posed a significant environmental water supply problem. In order to analyze the effects of seepage barriers on these subsurface outflows, the analytic element modeling code GFLOW was used to construct a ground water flow model of a region that includes a portion of the Everglades along with adjacent developed areas. The hydrology of this region can be characterized by a highly transmissive surficial aquifer in hydraulic contact with wetlands and canals. Calibration of the model to both wet and dry season conditions yielded satisfactory results, and it was concluded that the analytic element method is a suitable technique for modeling ground water flow in the Everglades environment. Finally, the model was used to evaluate the potential effectiveness of a subsurface barrier approximately two miles long for increasing water levels within the adjacent fringes of the Everglades National Park. It was found that the barrier had a negligible effect on water levels due to both its relatively short length and the high transmissivity of the surficial aquifer.     

Toward Reversal of Eutrophic Conditions in a Subtropical Estuary: Water Quality and Seagrass Response to Nitrogen Loading Reductions in Tampa Bay, Florida, USA

Coastal waters have been significantly influenced by increased inputs of nutrients that have accompanied population growth in adjacent drainage basins. In Tampa Bay, Florida, USA, the population has quadrupled since 1950. By the late 1970s, eutrophic conditions including phytoplankton and macroalgal blooms and seagrass losses were evident. The focus of improving Tampa Bay is centered on obtaining sufficient water quality necessary for restoring seagrass habitat, estimated to have been 16,400 ha in 1950 but reduced to 8800 ha by 1982. To address these problems, targets for nutrient load reductions along with seagrass restoration goals were developed and actions were implemented to reach adopted targets. Empirical regression models were developed to determine relationships between chlorophyll a concentrations and light attenuation adequate for sustainable seagrass growth. Additional empirical relationships between nitrogen loading and chlorophyll a concentrations were developed to determine how Tampa Bay responds to changes in loads. Data show that when nitrogen load reduction and chlorophyll a targets are met, seagrass cover increases. After nitrogen load reductions and maintenance of chlorophyll a at target levels, seagrass acreage has increased 25% since 1982, although more than 5000 ha of seagrass still require recovery. The cooperation of scientists, managers, and decision makers participating in the Tampa Bay Estuary Program’s Nitrogen Management Strategy allows the Tampa Bay estuary to continue to show progress towards reversing many of the problems that once plagued its waters. These results also highlight the importance of a multi-entity watershed management process in maintaining progress towards science-based natural resource goals.     

The use of constructed wetlands in the treatment of acid mine drainage

US government regulations require that all effluents from industrial operations, including mining, meet certain water quality standards. Constructed wetlands have proven to be useful in helping to attain those standards. Application of this biotechnology to mine water drainage can reduce water treatment costs and improve water quality in streams and rivers adversely affected by acidic mine water drainage from abandoned mines. Over 400 constructed wetland water treatment systems have been built on mined lands largely as a result of research by the US Bureau of Mines. Wetlands are passive biological treatment systems that are relatively inexpensive to construct and require minimal maintenance. Chemical treatment costs are reduced sufficiently to repay the cost of construction in less than a year. The mine waste water is typically treated in a series of excavated ponds that resemble small marsh areas. The ponds are engineered to facilitate bacterial oxidation of iron. Ideally, the water then flows through a composted organic substrate supporting a population of sulphate-reducing bacteria which raises the pH. Constructed wetlands in the USA are described - their history, functions, construction methodologies, applicabilities, limitations and costs.     

环境保护领域地方市级首次立法进展研究

为调研设区的市立法权放开后各地立法进展,通过全国各省市政府网站(除港澳台外)等公开渠道收集整理的各设区的市"首次立法"(第一部实体法,简称"首法")立法情况,发现截至2017年7月,全国89%新获立法权设区的市已完成"首法"立项,超一半新获立法权设区的市已顺利出台"首法"。从"首法"立项类型来看,约40%设区的市"首法"关注环境保护,仅次于城乡建设与管理类立法,表明环境保护是各地"首法"立法关注的重点领域之一。从地方环境"首法"立项类型来看,水环境保护领域条例立项数最多,其次是生态保护领域和大气污染防治领域;从地方环境"首法"立项分布来看,水环境保护类条例多分布于位于水系末端的沿海各省,大气污染防治条例则主要集中于京津冀及其周边空气质量较差的区域。当前国家高度重视生态文明建设,各地有必要抓住地方立法这一机遇,研究出台地方环境条例,助力地方环境管理水平的提升。     

农村工业化进程中的土地资源优化配置研究——以浙江永康市为例

在阐述农村工业化与土地资源优化配置关系问题的基础上，以浙江永康市为例，对当前我国农村工业化过程中土地资源优化配置问题进行了研究。研究表明，永康目前处于工业化中期阶段，工业用地扩张趋势明显，但同时也存在用地结构布局不甚合理、集约利用程度较低以及环境影响等问题。解决这些问题可通过切实保护耕地，合理安排建设用地规模与布局，提高土地集约利用率和控制环境污染等有效途径。     

新乡市环境质量变化原因及应对措施

通过对比分析新乡市2011年与2010年的监测数据,发现：环境空气质量、地表水河流控制断面有污染加重的趋势;气象条件、经济形势低迷、机动车尾气排放、交通干道堵塞是引起空气质量变化的原因;引起地表水质量变化的原因包括没有新鲜水源补给、结构性污染严重、其他城市来水污染、污水处理厂没有脱氮除磷设施。由此,提出了严格实行总量预算管理、转变经济增长方式、加强政府干预、加大环境监管、加强基础设施建设、河渠综合整治的改善环境质量的对策建议。     

An Overall Index of Environmental Quality in Coal Mining Areas and Energy Facilities

An approach to measuring environmental quality and trends in coal mining and industrial areas was attempted in this work. For this purpose, the establishment of a reference scale characterizing the status of environmental quality is proposed by developing an Environmental Quality Index (EQI). The methodology involves three main components: social research, the opinion of environmental experts, and the combination of new or existing indices. A survey of public opinion was carried out to identify the main environmental problems in the region of interest. Environmental experts carried out a survey, and the weights of specific environmental problems were obtained through a fuzzy Delphi method and pairwise comparison. The weight attributed to each environmental problem was computed, using new or existing indices (subindices) in the relevant literature. The EQI comprises a combination of the subindices with their own weights. The methodology was applied to a heavily industrialized coal basin in northwestern Macedonia, Greece. The results show that the new index may be used as a reliable tool for evaluating environmental quality in different areas. In addition, the study of EQI trends on an interannual basis can provide useful information on the efficiency of environmental policies already implemented by the responsible authorities.     

COST ANALYSIS OF WATER AND WASTE WATER TREATMENT PROCESSES IN DEVELOPING COUNTRIES1

ABSTRACT: Mathematical modeling techniques are used to develop predictive equations for cost of water and waste water treatment processes in developing countries utilizing socioeconomic, environmental, and technological indicators. Predictive equations are developed for each of the three regions (Africa, Asia, and Latin America) for construction, operation, and maintenance costs of slow sand filter, rapid sand filter, stabilization lagoon, aerated lagoon, activated sludge, and trickling filter. Data analysis indicated that cost of water treatment processes is a function of technological indicator (percentage of imported materials), population, and the design capacity. The variables which gave the best correlation for waste water treatment cost were population, design flow, and the percentage of imported waste water disposal materials.     

重庆市河堰村景观改变对水环境的影响

为了研究农村景观改变对水环境的影响,选取重庆市河堰村为研究对象,运用SWMM水文模拟软件,分析了研究区域的景观变迁与水量、水质变化的相互关系;通过访谈当地居民,分析了土地利用与景观变化对水环境的影响机制。认为(1)散点状的居民点分布模式与"村村通公路,户户通水泥"的农村道路建设以及庭院硬质化导致农村不透水表面面积迅速增加,缩短了雨水汇流时间并加速了污染物向水体的转移。(2)山体开发和现代农田水利工程的建设,如水库、山坪塘和排灌沟渠等的建设导致水体自净能力降低,加重了水体污染。(3)地表硬质化与河床沟渠化加速了水过程从而加速水环境的破坏。(4)人水关系由"我"、"你"变成"我"、"它",农民在卫生意识上升的同时缺乏相应的环保意识。