普光气田开发对地下水环境的影响分析

为最大程度缓解工程实施对当地地下水环境的破坏,文章在综合分析普光气田地质和水文地质特征的基础上,开展现场水质监测工作,选用内梅罗指数法评价区域地下水质量现状。结果表明:普光气田开发建设工程对区域地下水环境质量影响较小,地下水水质良好。在此基础上,探讨项目建设过程中的地下水环境影响因素,据此提出针对性的环境保护措施,以期为研究区地下水环境保护提供科学参考依据。     

油气田开发地下水环境监管面临的形势及对策

根据国家相继出台的《全国地下水污染防治规划(2011—2020年)》、《水污染防治行动计划》等地下水环境监管的法律法规和标准规范要求,分析了油气田开发存在的主要地下水环境风险:采油污水回注/回灌风险,油水井固井中套管损坏等造成的对地下水和土壤的污染,油水管道泄漏风险,固体废物处置设施渗漏风险。提出了在面临新的地下水环境监管形势下,油气田开发应采取的对策与建议:应进行地下水环境质量调查,并将其纳入HSE信息系统管理;建立健全地下水环境监管控制体系;在油气勘探开发中,防范地下水污染;加强开发项目前期地下水环境保护管理工作;开展地下水污染修复与防控试点工作。     

绵竹市地表水环境质量现状及水环境容量分析

本文通过对绵竹市污染源现状调查及地表水环境现状评价,计算并分析了境内主要河流的水环境容量。绵竹市地表水环境污染较为严重,水环境容量短缺已成为绵竹市主要环境制约因素。为实现绵竹市水环境保护与经济社会的可持续发展,需及时采取污染物总量控制、工业污染防治、生活污水处理、控制农村面源污染等一系列措施。     

浅谈地下水污染调查方法

地下水污染调查,是环境水文地质工作的一个中心内容。调查的主要目的是:以保护地下水供水水源为前提,查明地下水的污染状况,有害物质污染类别,污染过程和污染规律;确定地下水的污染源,判断地下水污染发展的趋势;为控制和消除污染,保护水源提出治理规划和防治措施;为完善水源地卫生防护带,为工业布局合理性提供依据,所以调查方法的科学性、综合性和逻辑性,是正确认识和查明地下水遭受各种因质污染的重要手段,是制定地下水水质改良方案,采取防御污染措施的先行步骤。鉴于地     

资阳市大气污染源排放清单研究

采用实地调研、资料收集等方式获得了2017年资阳市典型污染源的活动水平数据,参照城市大气污染物排放清单编制技术手册建立了基于排放因子法和物料衡算法的资阳市大气污染源排放清单,分析了主要污染物的行业排放特征和空间分布特征。结果表明,2017年资阳市SO₂、NO_X、CO、PM₁₀、PM_2.5、VOCs、NH₃总排放量分别为3.58kt、13.91kt、94.91kt、25.51kt、8.67kt、23.84kt和46.44kt。SO₂排放主要来自工业源;NOX排放主要来自移动源;CO排放主要来自工业过程及移动源;PM₁₀和PM_2.5、排放来自扬尘源和露天秸秆焚烧;VOCs主要来自溶剂使用源;NH₃主要来自农业活动。资阳市主要污染物排放分布在工业点源较为集中的雁江区和安岳县,乐至县污染物排放量相对较小。     

国土空间规划视角下流域水环境改善潜力——以长春市第二松花江流域为例

国土空间规划对新时期流域水环境保护意义重大。本文结合国土空间规划对流域水环境影响的全过程(污染产生—污染排放—污染入河)机制,构建了国土空间规划视角下流域水环境变化评估指标体系和框架。以长春市第二松花江流域为例,利用系统动力学模型和一维水动力模型QUAL2K量化了国土空间规划对流域水环境的影响。结果表明,到国土空间规划近期目标年(2025年),流域水环境状况良好,体现为流域大部分河段COD和NH₃-N达标,水环境容量最小为44.96 kg/d和5.10 kg/d。国土空间规划中的总量目标、环保设施建设和相关布局的实施将会使COD和NH₃-N污染产生量降低52.61%和14.16%;污染排放量降低26.45%和59.09%;水环境容量增加10.68%和57.17%。总体而言,国土空间规划对流域水环境改善潜力巨大,同时改善潜力因不同区域、污染源、污染物而异。本研究提出的评估框架为国土空间规划背景下流域水环境保护提供了思路。     

四川天府新区地下水污染源荷载评估

地下水污染源荷载评估是地下水污染防治中一项重要内容,能为地下水污染防治提供污染危害等级数据。以四川天府新区为例,在收集污染源统计资料并开展地下水污染源调查基础上,筛选单个污染源的污染物的毒性(T)、污染的可能性(L)、污染物从污染源可能释放到地下水体的量(Q)3个定量指标,利用评分指数法获得单个污染源荷载风险等级值。利用GIS软件插值法编制8种类型污染源荷载等级分区图,根据各类污染源权重指标分区计算,最终得到地下水污染源荷载评估综合分区图,并将天府新区地下水污染源荷载分为5级。研究表明集中式工业园区对污染源荷载等级的贡献最大,二者具有高度的耦合性。     

特大城市河流水环境质量时空变化特征及污染源分析：以成都市为例

以成都市主要流域为例,阐明和辨析其河流水环境质量时空变化趋势和污染特征,为特大城市的生态环境保护决策提供依据。基于2011～2020年成都市河流75个监测断面22项指标的逐月数据,采用内梅罗污染指数法和SOM聚类法,通过多元统计分析手段,研究成都市河流水质状况和时空变化特征,并分析其潜在的污染来源。结果表明,75个监测断面中45个“清洁”,5个“较清洁”,1个“轻污染”,21个“中污染”,无“重污染”;“十二五”期间污染断面比例为～36.9%,“十三五”期间污染断面比例由43.0%大幅度下降至2.7%,说明成都市水环境管理与治理措施卓有成效;610个断面年均数据可分为8组,中下游水质普遍较差且差异大,COD_Mn、COD_Cr、BOD₅、NH₃-N和TP是研究区域主要污染因子。成都市河流水质深受人类活动干扰,农业面源、生活污水和畜禽养殖废水污染问题是持续改善成都市水环境的重要任务。     

油气钻井作业对地下水污染治理研究＊

分析了钻井作业对地下水污染的特点、污染途径,针对性地提出了钻井作业对地下水污染的预防措施,以及污染物处理技术,其中氧化还原技术、气体抽取技术、环境生物技术主要用于有机物污染治理,SRB技术、废弃钻井液固化技术、钻井液转换为水泥浆(MTC)的固井技术可用于处理废弃钻井液。钻井引起的污染治理应以"预防为主,防治结合",切实推行清洁生产和HSE管理。     

峨眉河乐山市中区段水环境污染及防治对策

为了确保峨眉河乐山市中区段水环境质量满足社会经济的发展,在全面调查峨眉河流域污染现状的基础上,对该流域水环境进行系统的分析和评价,得出乐山市中区段水环境质量达到国家《地表水环境质量标准》（GB3838—2002）中Ⅱ类水质标准,流域的主要污染为城镇生活污染源。同时,计算出峨眉河的水环境容量,提出对污染源施行总量控制方案。并根据峨眉河流域污染源的实际情况,针对城镇生活污染源、工业污染源和面源的不同特点提出具体的防治对策。     

Conversion of temperate forests into heaths: Role of ecosystem disturbance and ericaceous plants

Fire and logging in nutrient-poor temperate forests with certain ericaceous understory plants may convert the forests into heaths. The process of disturbance-induced heath formation is documented by using examples ofCalluna in western Europe,Kalmia in Newfoundland, andGaultheria (salal) in coastal British Columbia. In a cool, temperate climate, rapid vegetative growth ofCalluna, Kalmia, and salal following disturbance results in increasing organic accumulation (paludification), nutrient sequestration, soil acidification, and allelochemicals. These are thought to be the main reasons to conifer regeneration failure in disturbed habitats. If continuation in forest is a land-use objective, then temperate forests with an ericaceous understory should not be logged unless effective silvicultural methods are devised to control the ericaceous plants and restore forest regeneration. Preharvest vegetation control may be considered as an option. Failure to control the understory plants may lead to a long-term vegetation shift, from forest to heathland, particularly in nutrient-poor sites. Successful methods of controllingKalmia andGaultheria, however, have yet to be developed. While theKalmia- andGaultheria- dominated heathlands are undesirable in Canada and the Pacific Northwest, a wide range ofCalluna heathlands of western Europe are being conserved as natural and seminatural vegetation.     

Urban ecological systems: scientific foundations and a decade of progress

Urban ecological studies, including focus on cities, suburbs, and exurbs, while having deep roots in the early to mid 20th century, have burgeoned in the last several decades. We use the state factor approach to highlight the role of important aspects of climate, substrate, organisms, relief, and time in differentiating urban from non-urban areas, and for determining heterogeneity within spatially extensive metropolitan areas. In addition to reviewing key findings relevant to each state factor, we note the emergence of tentative "urban syndromes" concerning soils, streams, wildlife and plants, and homogenization of certain ecosystem functions, such as soil organic carbon dynamics. We note the utility of the ecosystem approach, the human ecosystem framework, and watersheds as integrative tools to tie information about multiple state factors together. The organismal component of urban complexes includes the social organization of the human population, and we review key modes by which human populations within urban areas are differentiated, and how such differentiation affects environmentally relevant actions. Emerging syntheses in land change science and ecological urban design are also summarized. The multifaceted frameworks and the growing urban knowledge base do however identify some pressing research needs.     

AN APPLICATION RUNOFF MODEL STRATEGY FOR UNGAGED WATERSHEDS1

ABSTRACT: Mathematical models for predicting watershed surface flow responses are available, most of which are elaborate nonlinear numerical surface and channel flow models linked with infiltration models. Such models may be used to make predictions for ungaged areas, assuming an acceptable fitting of the model to the topography and roughness of the real system. For some application purposes, these models are impractical because of their complexity and expensive computer solutions. A procedure is developed that uses a complex model of an ungaged area to derive a simpler parametric nonlinear system model for repetitious simulation with input sequences. The predicted flow outputs are obtained with the simpler model at significant savings of money and time. The procedures for constructing a complex kinematic model of a 40 acre (161,880 m²) reference watershed and deriving the simpler system model are outlined. The results of predictions from both models are compared with a selected set of measured events, all having essentially the same initial conditions. Peak discharges ranged from 3 to 118 ft³/sec (0.085 to 3.34 m³/sec), which includes the largest event of record. The inherent limitations of lumped systems models are demonstrated, including the bias caused by their inability to model infiltration losses after rainfall ceases. Computer costs and times for the models were compared. The derived simple model has a cost advantage when repeated use of a model is required. Such an applications hydrologic model has an engineering tradeoff of reduced accuracy, and lumping bias, but is more economical for certain design purposes.     

Neighbourhood characteristics and urban gardens in the Toledo metropolitan area: staffing and voluntarism,food production,infrastructure, and sustainability practices

Urban gardens are important sources of sustenance for communities with limited access to food. Hence, this study focuses on food production in gardens in the Toledo metropolitan area in Northwest Ohio. We administered surveys to 150 garden managers from November 2014 to February 2015 in our attempt to better understand how neighbourhood racial composition and poverty levels are related to staffing and voluntarism, food production and distribution, the development of infrastructure, and the adoption of sustainability practices in urban gardens. The results from 30 gardens are presented in this paper. We used Geographic Information Systems to map the gardens and overlay the map with 2010 census data so that we could conduct demographic analyses of the neighbourhoods in which the gardens were located. Though the gardens were small – two acres or less – up to 46 varieties of food were grown in a single garden. Gardens also operated on small budgets. Food from the gardens was gifted or shared with friends, family, and neighbourhood residents. Gardens in predominantly minority neighbourhoods tended to have fewer institutional partners, less garden infrastructure, and had adopted fewer sustainable practices than gardens in predominantly White neighbourhoods. Nonetheless, residents of predominantly minority and high-poverty neighbourhoods participated in garden activities and influenced garden operations. Volunteering and staffing were racialised and gendered.     

Using Paleo Reconstructions to Improve Streamflow Forecast Lead Time in the Western United States

In water stressed regions, water managers are exploring new horizons that would help in long‐range streamflow forecasts. Oceanic‐atmospheric oscillations have been shown to influence streamflow variability. In this study, long‐lead time streamflow forecasts are made using a multiclass kernel‐based data‐driven support vector machine (SVM) model. The extended streamflow records based on tree ring reconstructions were used to provide a longer time series data. Reconstructed data were used from 1658 to 1952 and the instrumental record was used from 1953 to 2007. Reconstructions for oceanic‐atmospheric oscillations included the El Niño‐Southern Oscillation, Pacific Decadal Oscillation, Atlantic Multidecadal Oscillation, and North Atlantic Oscillation. Streamflow forecasts using all four oscillations were made with one‐year to five‐year lead times for 21 gages in the western United States. This is the first study that uses both instrumental and reconstructed data of oscillations in SVM model to improve streamflow forecast lead time. SVM model was able to provide “satisfactory” to “very good” forecasts with one‐ to five‐year lead time for the selected gages. The use of all the oscillation indices helped in achieving better predictability compared to using individual oscillations. The SVM modeling results are better when compared with multiple linear regression model forecasts. The findings are statistical in nature and are expected to be useful for long‐term water resources planning and management.     

Predicting deer-vehicle collisions in an urban area

Collisions with deer and other large animals are increasing, and the resulting economic costs and risks to public safety have made mitigation measures a priority for both city and wildlife managers. We created landscape models to describe and predict deer-vehicle collision (DVCs) within the City of Edmonton, Alberta. Models based on roadside characteristics revealed that DVCs occurred frequently where roadside vegetation was both denser and more diverse, and that DVCs were more likely to occur when the groomed width of roadside right-of-ways was smaller. No DVCs occurred where the width of the vegetation-free or manicured roadside buffer was greater than 40 m. Landscape-based models showed that DVCs were more likely in more heterogeneous landscapes where road densities were lower and speed limits were higher, and where non-forested vegetation such as farmland was in closer proximity to larger tracts of forest. These models can help wildlife and transportation managers to identify locations of high collision frequency for mitigation. Modifying certain landscape and roadside habitats can be an effective way to reduce deer-vehicle collisions.     

MANGANESE CYCLE IN IMPOUNDMENT WATER

Manganese entering impounded water will undergo a cyclic transformation. Oxidation precipitates manganese from top waters. At the bottom of the lake, biological activity will render manganese soluble by both intracellular as well as extracellular activity. The study was made to demonstrate that biological reduction and transformation, organometallic complexation, together with the presence of carbon dioxide and the lowering of pH all have some effect on the solubility of manganese. Dissolved manganese may be brought back to top waters during the lake overturn and therefore deteriorates the water quality.     

Biodiversity and biotechnology

The maintenance of biodiversity is urged from many quarters and on grounds ranging from aesthetic considerations to its usefulness, particularly for biotechnology. But regardless of the grounds for preserving biodiversity, writers are generally in agreement that it should be preserved. But, in examining the various references biodiversity, such as species diversity, genetic diversity, and habitat diversity, it is apparent that we cannot aim to preserve biodiversityas such, since there are a number of conflicts in any such undertaking. In preserving one aspect of biodiversity, we damage another aspect. Five arguments which attempt to ground our moral concern for biodiversity are reviewed and critiqued, not only for their consistency but also for their power to move us to action. The final section of the paper shows how conflicts in the values of personal and environmental health can impair ethical action and especially policy formation.An earlier version of this paper was read at the conference on Agriculture, Food, and Human Values: Tradition and Change, Orlando, Florida, October 7–9, 1987.     

Surface applied water treatment residuals affect bioavailable phosphorus losses in Florida sands

Water treatment residuals (WTR) can reduce runoff P loss and surface co-application of P-sources and WTR is a practical way of land applying the residuals. In a rainfall simulation study, we evaluated the effects of surface co-applied P-sources and an Al-WTR on runoff and leacheate bioavailable P (BAP) losses from a Florida sand. Four P-sources, namely poultry manure, Boca Raton biosolids (high water-soluble P), Pompano biosolids (moderate water-soluble P), and triple super phosphate (TSP) were surface applied at 56 and 224kgPha(-1) (by weight) to represent low and high soil P loads typical of P- and N-based amendments rates. The treatments further received surface applied WTR at 0 or 10gWTRkg(-1) soil. BAP loss masses were greater in leachate (16.4-536mg) than in runoff (0.91-46mg), but were reduced in runoff and leachate by surface applied WTR. Masses of total BAP lost in the presence of surface applied WTR were less than approximately 75% of BAP losses in the absence of WTR. Total BAP losses from each of the organic sources applied at N-based rates were not greater than P loss from TSP applied at a P-based rate. The BAP loss at the N-based rate of moderate water-soluble P-source (Pompano biosolids) was not greater than BAP losses at the P-based rates of other organic sources tested. The hazards of excess P from applying organic P-sources at N-based rates are not greater than observed at P-based rates of mineral fertilizer. Results suggest that management of the environmental P hazards associated with N-based rates of organic materials in Florida sands is possible by either applying P-sources with WTR or using a moderate water-soluble P-source.     

Sources and Transport of Phosphorus to Rivers in California and Adjacent States,U.S., as Determined by SPARROW Modeling

The SPARROW (SPAtially Referenced Regression on Watershed attributes) model was used to simulate annual phosphorus loads and concentrations in unmonitored stream reaches in California, U.S., and portions of Nevada and Oregon. The model was calibrated using de‐trended streamflow and phosphorus concentration data at 80 locations. The model explained 91% of the variability in loads and 51% of the variability in yields for a base year of 2002. Point sources, geological background, and cultivated land were significant sources. Variables used to explain delivery of phosphorus from land to water were precipitation and soil clay content. Aquatic loss of phosphorus was significant in streams of all sizes, with the greatest decay predicted in small‐ and intermediate‐sized streams. Geological sources, including volcanic rocks and shales, were the principal control on concentrations and loads in many regions. Some localized formations such as the Monterey shale of southern California are important sources of phosphorus and may contribute to elevated stream concentrations. Many of the larger point source facilities were located in downstream areas, near the ocean, and do not affect inland streams except for a few locations. Large areas of cultivated land result in phosphorus load increases, but do not necessarily increase the loads above those of geological background in some cases because of local hydrology, which limits the potential of phosphorus transport from land to streams.