Projected Changes in Discharge in an Agricultural Watershed in Iowa

Our improved capability to adapt to the future changes in discharge is linked to our capability to predict the magnitude or at least the direction of these changes. For the agricultural United States Midwest, too much or too little water has severe socioeconomic impacts. Here, we focus on the Raccoon River at Van Meter, Iowa, and use a statistical approach to examine projected changes in discharge. We build on statistical models using rainfall and harvested corn and soybean acreage to explain the observed discharge variability. We then use projections of these two predictors to examine the projected discharge response. Results are based on seven global climate models part of the Coupled Model Intercomparison Project Phase 5 and two representative concentration pathways (RCPs 4.5 and 8.5). There is not a strong signal of change in the discharge projections under the RCP 4.5. However, the results for the RCP 8.5 point to a stronger changing signal related to larger projected increases in rainfall, resulting in increased trends, in particular, in the upper part of the discharge distribution (i.e., 60th percentile and above). Examination of two hypothetical agricultural scenarios indicates that these increasing trends could be alleviated by decreasing the extent of the agricultural production. We also discuss how the methodology presented in this study represents a viable approach to move forward with the concept of return period for engineering design and management in a nonstationary world.     

Pesticides in rain in four agricultural watersheds in the United States

Rainfall samples were collected during the 2003 and 2004 growing seasons at four agricultural locales across the USA in Maryland, Indiana, Nebraska, and California. The samples were analyzed for 21 insecticides, 18 herbicides, three fungicides, and 40 pesticide degradates. Data from all sites combined show that 7 of the 10 most frequently detected pesticides were herbicides, with atrazine (70%) and metolachlor (83%) detected at every site. Dacthal, acetochlor, simazine, alachlor, and pendimethalin were detected in more than 50% of the samples. Chlorpyrifos, carbaryl, and diazinon were the only insecticides among the 10 most frequently detected compounds. Of the remaining pesticide parent compounds, 18 were detected in fewer than 30% of the samples, and 13 were not detected. The most frequently detected degradates were deethylatrazine; the oxygen analogs (OAs) of the organophosphorus insecticides chlorpyrifos, diazinon, and malathion; and 1-napthol (degradate of carbaryl). Deethylatrazine was detected in nearly 70% of the samples collected in Maryland, Indiana, and Nebraska but was detected only once in California. The OAs of chlorpyrifos and diazinon were detected primarily in California. Degradates of the acetanilide herbicides were rarely detected in rain, indicating that they are not formed in the atmosphere or readily volatilized from soils. Herbicides accounted for 91 to 98% of the total pesticide mass deposited by rain except in California, where insecticides accounted for 61% in 2004. The mass of pesticides deposited by rainfall was estimated to be less than 2% of the total applied in these agricultural areas.     

Investment in human capital in Africa

Summary The author analyses the problems currently faced by the African continent, recognises six factors which he believes are important in influencing the analysis, and argues that the only secure, renewable asset any country or continent has, is its people. He maintains that people development, rather than the classical economic forms of encouraging development, offers Africa a viable way forward. He then identifies a number of specific issues within such a strategy of investment in human capital.Brian Walker is the President of the International Institute for Environment and Development (IIED), and this address was given at the inaugural meeting of the International Year of Shelter for the Homeless, in London, on 18th April, 1985. A second, earlier, associated address was published inThe Environmentalist 5(3) 167–170.     

Environmental assessment in countries in transition: evolution in a changing context

Over the last fifteen years, Environmental Assessment systems of transitional societies of Central and Eastern Europe and Central Asia have undergone dramatic change from appraisals integrated into centrally planned economies to formal procedures aimed to ensure interdisciplinary analysis of environmental impacts and linked to publicly accountable decision-making. In most Central European nations, EA systems have been radically reformed to approximate the procedures used in developed countries, particularly in the European Union. In contrast, EA in most of the former Soviet republics has been reformed more gradually and is still based on the so-called State Environmental Review procedure inherited from the USSR and substantially different from 'Western' EA. About one-third of the transitional countries (in the Balkans, the Caucasus and Central Asia) have, so far, failed to establish functioning EA systems. Throughout the region, there has been a gap between EA legislation and practice, especially concerning interdisciplinary analysis of environmental impacts, public participation, and utilisation of EA findings in decision-making. A key driving force in the reform of EA systems has been the change in their societal context, the so-called 'process of transition'. Three main policy agendas--environmental protection, reforms of decision-making, and conforming to international requirements--along with the institutional context of EA regulations and practice have influenced both the change of EA systems over time and the regional variations in the patterns of their evolution. This study suggests that an effective reform of an EA system should be context-sensitive, or be 'in gear' with the political and economic transition. Future EA research should consider their changing societal contexts and focused on practical effects of applying EA procedures.     

Community-company relations in gold mining in Ghana

As a result of Structural Adjustment Programme from the 1980s, many developing countries have experienced an increase in resource extraction activities by international and transnational corporations. The work reported here examines the perceived impacts of gold mining at the community level in the Wassa West District of Ghana, Africa and discusses those perceived impacts in the context of globalization processes and growing multinational corporate interest in Corporate Social Responsibility (CSR). Interview data compared community members' perceptions with those of company representatives in three communities. The results indicate that communities held companies responsible for a series of economic, social, and environmental changes. While recognizing some of the benefits brought by the mines, communities felt that the companies did not live up to their responsibility to support local development. Companies responded by denying, dismissing concerns, or shifting blame. Findings from this work show that lack of engagement and action by government agencies at all levels resulted in companies acting in a surrogate governmental capacity. In such situations, managing expectations is key to community-company relations.     

电催化氧化处理难降解废水技术研究进展

电催化氧化处理难降解废水技术已得到了广泛关注.本文从电极材料与应用,电极结构及反应器形状,以及与其它处理方法联用等综述了最新研究进展,并在此基础上总结出了电催化氧化技术今后的发展方向.     

Water management problems in economies in transition

Ambitious programmes of reform in Central and Eastern Europe (CEE) are threatened by a serious deterioration of the environment. Large-scale damage of the natural environment in many forms, including water pollution has created development barriers which adversely affect the living conditions of current and future generations. Despite similar patterns of environmental policy in the CEE countries compared with their Western counterparts, neither environmental legislation nor economic incentives have produced any significant improvement in water quality over the last 10–20 years. For that very reason in the transition period, it is necessary to identify existing deficiencies in the system and to build up a mixed system of new institutions of water management, more realistic legislation with a strong enforcement system, and market based incentives for water conservation and protection against pollution.     

Sustainability Appraisal in neighbourhood planning in England

The preparation of strategic environmental assessment (SEA) inclusive sustainability appraisals (SAs) for neighbourhood plans (NPs) in England may be required when significant environmental effects are expected to arise from an NP. In this paper, we report on the result of a Ph.D. project, conducted between 2012 and 2015, in which all 15 NP SEA inclusive SAs that had been completed at the time were evaluated. In this context, the quality of SA practice was found to differ substantially. SAs were prepared either ‘in-house’ (i.e. by neighbourhood planning steering groups) or by consultants. The quality of SAs was found to be associated with their overall perceived degree of influence on the underlying NPs. Whilst the focus of this paper is on practice in England, findings are expected to be of interest to a wider international audience, in particular to those experimenting with voluntary neighbourhood/local level plan SA/SEA.     

我国城市生态评价研究进展

城市建设带来了越来越多的生态环境问题，生态城市建设是解决这些问题的良好途径。生态城市的建设要有一定的评价体系作为支撑，本文综述了国内基于AHP方法建立的应用较为广泛的城市生态评价体系和方法，并对国内城市生态评价的现状做了分析。     

Private participation in isolated grids in Mozambique

This article presents a case study from Mozambique of the electrification of two selected towns under a World Bank financed project. Low-cost electricity services were extended to the two isolated areas after an enabling framework had been created for private sector participation. The World Bank project also demonstrates that the private sector can be attracted to participate in rural electrification schemes even in a poor country. The example shown in this article is one of the few of its kind in SubSaharan Africa.     

Status and trends in EFlows in southern Africa

Environmental Flows (EFlows) are defined as the quantity, timing and quality of the flow of water, sediment and biota necessary to sustain freshwater and estuarine ecosystems, and the human livelihoods and well-being that depend on these ecosystems. As such they are a vital component of Integrated Water Resource Management (IWRM). A recent survey found that, in general, Africa lags behind schedule with respect to the global SDG Target 6.5 to implement IWRM at all levels, including through transboundary cooperation as appropriate. This web-based review explores progress made in EFlows Assessments and implementing their outcomes in southern Africa. It outlines the apparent impetus to the uptake of EFlows provided by legislation, common funding mechanisms for EFlows assessment and evolving trends in EFlows assessment. It also highlights instances of implementation of EFlows in both in-country and transboundary settings.     

Issues in natural resources management in developing countries

Recognizing the steady depletion of natural resources in developing countries, this study analyses its causes by focusing on the ownership of such resources. Resource degradation was found associated with an array of individual, socioeconomic, politicoeconomic and institutional factors. In the pursuit of sustainable regional resources management and conservation, it is necessary to analyse and incorporate these multifarious factors into the design of a comprehensive strategy. While local government should be responsible for devising management strategies, their implementation requires the interfacing of field agencies with local communities that are to be assisted in the short term and instructed in depth; their performance should be closely monitored over the long term.     

Denitrification in alluvial wetlands in an urban landscape

Riparian wetlands have been shown to be effective "sinks" for nitrate N (NO3-), minimizing the downstream export of N to streams and coastal water bodies. However, the vast majority of riparian denitrification research has been in agricultural and forested watersheds, with relatively little work on riparian wetland function in urban watersheds. We investigated the variation and magnitude of denitrification in three constructed and two relict oxbow urban wetlands, and in two forested reference wetlands in the Baltimore metropolitan area. Denitrification rates in wetland sediments were measured with a 15N-enriched NO3- "push-pull" groundwater tracer method during the summer and winter of 2008. Mean denitrification rates did not differ among the wetland types and ranged from 147 +/- 29 microg N kg soil(-1) d(-1) in constructed stormwater wetlands to 100 +/- 11 microg N kg soil(-1) d(-1) in relict oxbows to 106 +/- 32 microg N kg soil(-1) d(-1) in forested reference wetlands. High denitrification rates were observed in both summer and winter, suggesting that these wetlands are sinks for NO3- year round. Comparison of denitrification rates with NO3- standing stocks in the wetland water column and stream NO3- loads indicated that mass removal of NO3- in urban wetland sediments by denitrification could be substantial. Our results suggest that urban wetlands have the potential to reduce NO3- in urban landscapes and should be considered as a means to manage N in urban watersheds.     

Evaluating changes in matrix-based, recovery-adjusted concentrations in paired data for pesticides in groundwater

Pesticide concentration data for waters from selected carbonate-rock aquifers in agricultural areas of Pennsylvania were collected in 1993-2009 for occurrence and distribution assessments. A set of 30 wells was visited once in 1993-1995 and again in 2008-2009 to assess concentration changes. The data include censored matched pairs (nondetections of a compound in one or both samples of a pair). A potentially improved approach for assessing concentration changes is presented where (i) concentrations are adjusted with models of matrix-spike recovery and (ii) area-wide temporal change is tested by use of the paired Prentice-Wilcoxon (PPW) statistical test. The PPW results for atrazine, simazine, metolachlor, prometon, and an atrazine degradate, deethylatrazine (DEA), are compared using recovery-adjusted and unadjusted concentrations. Results for adjusted compared with unadjusted concentrations in 2008-2009 compared with 1993-1995 were similar for atrazine and simazine (significant decrease; 95% confidence level) and metolachlor (no change) but differed for DEA (adjusted, decrease; unadjusted, increase) and prometon (adjusted, decrease; unadjusted, no change). The PPW results were different on recovery-adjusted compared with unadjusted concentrations. Not accounting for variability in recovery can mask a true change, misidentify a change when no true change exists, or assign a direction opposite of the true change in concentration that resulted from matrix influences on extraction and laboratory method performance. However, matrix-based models of recovery derived from a laboratory performance dataset from multiple studies for national assessment, as used herein, rather than time- and study-specific recoveries may introduce uncertainty in recovery adjustments for individual samples that should be considered in assessing change.     

Recent progress in coal bioprocessing research in Europe

European work on the application of biotechnology to processing various coals is reviewed and set within a wider context. Both U.S. and European work are discussed. In connection with work on microbial desulphurisation, European effort, particularly that centred on Delft University in the Netherlands, has concentrated on looking towards practical plant designs based on kinetic reaction data obtained in the laboratory. The question of desulphurisation looks rather different from a European (and world) perspective, compared with the situation in the U.S. There are, for example, several countries with high sulphur, low rank coals, where a higher proportion of the sulphur is present in organic form.While the work on pyrite removal has been well documented and has been replicated by different workers, that on organic sulphur removal is at a much earlier stage. In the U.K., work is going on to enhance the physical separation processes currently used in coal cleaning, using micro-organisms to alter the surface properties of various particles during flotation. This approach has the possibility of relatively short-term application and low capital costSome fundamental studies looking for organisms to attack and degrade the coal molecule, particularly in the F.R.G., have been based on bituminous coal. This contrasts with U.S. work which has met with some success with lignites and weathered lignite in the form of leonardite.The use of biotechnology in connection with coal must be looked at principally as a potential long-term development. The inherent problems associated with the nature of coal must be recognised but research work is already demonstrating possibilities that even 5 or 10 years ago would have been discounted. With advances in analytical techniques, one of the first benefits to be gained may well be a better knowledge and understanding of coal structure from looking at its degradation products.     

生物体内有机氯农药的研究进展

有机氯农药是高残留农药，进入生物体后会长期残留，对生物体产生危害。近年来，生物体中的有机氯农药的研究越来越引起各国环境化学家、生态学家的重视，渐渐成为环境化学、生态毒理学研究的热点之一。本文总结了近年来国际上有关生物体内有机氯农药的研究进展情况，以及所取得的主要研究成果。     

Changes in water resources administration in Latin America

Traditionally, in most countries of Latin America, the management of water and water based services has been highly centralized in the public sector. Recently, as the role of government has been reconsidered, many services have been transferred to lower levels of government or to the private sector. At the same time, the emphasis given to water projects as basic development tools has given way to the environmental significance of good water management. Consequently, the approach to water resources management has been modified and space created for the adoption of some of the basic precepts enunciated in the Mar del Plata Action Plan and Agenda 21. In particular, in various countries consideration is being given to water management through river basin institutions .     

壬基酚的土壤残留及其行为研究进展

壬基酚（NP）是类环境激素物质,具有生物致毒性,在水体、污泥、沉积物中存在普遍,且对食品安全构成威胁,但国内对土壤中壬基酚的残留水平知之甚少。本文对国内外土壤等环境中壬基酚的残留现状及其来源进行总结,综述了土壤环境中残留壬基酚的吸附解吸、淋溶迁移、降解代谢等环境行为及其影响因素,并对未来工作提出展望,以期为进一步开展土壤环境壬基酚的污染调查及其评价研究提供借鉴。