A regional environmental information system for analyzing and predicting the impacts of nonferrous mining on an agricultural environment

Mineral exploitation is a necessary component of China's economic development goals. Such exploitation brings with it the potential for serious environmental degradation. Careful environmental impact assessments of mining projects are required in order to implement China's environmental protection law and identify measures for protecting surrounding agricultural environments. This article describes an environmental information system that has been developed for the purpose of assisting with the environmental impact assessment of nonferrous mining operations with a particular focus on agricultural impacts. An application of the environmental information system to the Yongping copper mine, located in Jiangxi Province, is discussed. The role of the environmental information system is analyzing and predicting soil contamination from heavy metals and other types of impacts from this mining operation is described. The environmental information system is designed for implementation on an IBM PC/XT microcomputer. The experience gained from the Yongping copper mine application and the growing popularity of microcomputers in China indicate a significant potential for the effective use of a microcomputer-based environmental information system in other parts of China.     

Forests and competing land uses in Kenya

Indigenous forests in Kenya, as in other developing countries, are under heavy pressure from competing agricultural land uses and from unsustainable cutting. The problem in Kenya is compounded by high population growth rates and an agriculturally based economy, which, even with efforts to control birth rates and industrialize, will persist into the next century. Both ecological and economic consequences of these pressures need to be considered in land-use decision making for land and forest management to be effective. This paper presents one way to combine ecological and economic considerations. The status of principal forest areas in Kenya is summarized and competing land uses compared on the basis of ecological functions and economic analysis. Replacement uses do not match the ecological functions of forest, although established stands of tree crops (forest plantations, fuel wood, tea) can have roughly comparable effects on soil and water resources. Indigenous forests have high, although difficult to estimate, economic benefits from tourism and protection of downstream agricultural productivity. Economic returns from competing land uses range widely, with tea having the highest and fuel wood plantations having returns comparable to some annual crops and dairying. Consideration of ecological and economic factors together suggests some trade-offs for improving land allocation decisions and several management opportunities for increasing benefits or reducing costs from particular land uses. The evaluation also suggests a general strategy for forest land management in Kenya.The views and interpretations expressed in this article are those of the authors and should not be attributed to the World Bank, its affiliated organizations, or any individual acting on their behalf.     

Minimizing contamination hazards to waterbirds using agricultural drainage evaporation ponds

In much of the San Joaquin Valley, California, USA, inadequate drainage of applied irrigation water and accumulating salts in the soil have necessitated the installation of subsurface tile drainage systems to preserve crop productivity. At present, these subsurface drainage waters are disposed of by means of evaporation ponds or discharges into the San Joaquin River. Unfortunately, most of these agricultural drainage waters contain high concentrations of salts and naturally occurring trace elements, such as selenium, and recent evidence indicates that substantial numbers of waterbirds are exposed to contamination by selenium in the evaporation ponds. In order to avoid, minimize, or mitigate the adverse impacts on wildlife using the ponds, alternative pond management methods must be identified and evaluated for implementation. A number of methods have the potential to be cost-effective in significantly reducing the contamination hazard to birds using agricultural evaporation ponds. Twenty general methods were evaluated in this study, and four methods are recommended for implementation: remove levee vegetation, remove windbreaks, deepen the ponds, and haze birds. A number of other methods are recommended for further consideration because they appear to have good prospects for reducing the contamination hazard: steepen interior levee slopes, apply herbicides and insecticides, place netting on pond shorelines, and provide freshwater habitat adjacent to evaporation ponds. It may be necessary to use a combination of methods to effectively control selenium contamination of aquatic birds because it is unlikely that a single affordable pond management method will be able to entirely eliminate the contamination hazard.     

Pesticide residues in biological waste

The aim of this study was to detect crop protection products (CPP) in single fractions of biological waste and to estimate pesticide concentrations in biological waste, depending on its composition. The composition of biological waste was determined from the literature, which provided information on its local and seasonal variability. The residue analysis included 17 pesticides for the analysis of tropical fruit peels and 48 pesticides for other fractions, e.g. vegetables, other fruits and ornamental flowers. The freeze-dried samples were extracted ultrasonically and purified by means of gel permeation chromatography. The analysis was carried out using gas chromatography with a mass selective detector in the selected ion monitoring mode. All tropical fruit peels contained CPP-residues. Thiabendazole was the most important contaminant with respect to the concentration and frequency of occurrence. The vegetables, other fruits and flowers also contained CPP-residues, such as the fungicides captan and dodemorph and the insecticide endosulfan. Based on import data and the composition of biological waste, the CPP-content of biological waste was estimated for rural and urban areas in summer and winter. Due to the higher percentage of tropical fruit peels, thiabendazole was the main contaminant in winter. The total concentration of CPP, summed up over all substances, ranged between 828 and 1829 μg (kg ww)⁻¹.     

农业面源污染模型研究进展

综述了农业面源污染模型国内外研究进展,介绍了常用的面源污染模型概念与适用范围,明确"3S"技术与SWAT、AGNPS等模型有机结合是当今面源污染模型的研究热点。提出我国面源污染模型未来研究的重点是围绕水质改善目标,建立面向全流域尺度的面源污染负荷估算方法,构建完整的基础监测数据网络,为建立符合我国流域特性的面源污染模型提供支撑。     

“新三农”视域下中国耕地利用的可持续集约化：概念认知与研究框架

耕地利用的可持续集约化为保障粮食安全、农业绿色发展和资源永续利用提供了新思路,对于深化农民主体地位、夯实农业发展的现代化导向、破解“新三农”复杂的问题集合具有重要的现实意义。系统梳理国外可持续集约化的思想缘起,辨析可持续集约化的内涵差异,厘清“新三农”视域下中国耕地利用可持续集约化的逻辑本源;基于要素融合—结构重整—功能优化的运行轨迹,遵循耕地利用系统过程—格局—机制—效应的逻辑进路,尝试从学理辨析、水平测度、演化机理和优化调控等方面厘清耕地利用系统基本问题域并阐释其研究主题,构建耕地利用可持续集约化的研究框架。探索性提出未来研究需重点关注的农业生态空间—人地关系—耕地利用可持续集约化等科学问题,探讨因素+机理、功能+系统、过程+格局、尺度+界面的关键路径。     

Panel heterogeneous distribution analysis of trade and modernized agriculture on CO2 emissions: The role of renewable and fossil fuel energy consumption

In line with the global target of reducing climate change and its impact, this study explored the causal relationship between CO₂ emissions, modernized agriculture, trade openness, aggregate and disaggregate energy consumption in 14 African countries from 1990–2013 using a panel quantile estimation procedure. The empirical results showed that value addition to agricultural commodities declines CO₂ emissions in countries with high pollution levels. The study revealed a positive nexus between CO₂ emissions and energy consumption homogeneously distributed across quantiles. Trade openness was found to lower CO₂ emissions in countries with lower and higher levels of environmental pollution. While fossil fuel energy consumption was found to exacerbate CO₂ emissions, renewable energy consumption confirmed its mitigating effect on environmental pollution. The institution of climate‐smart agricultural options will sustainably increase productivity and income while adapting to climate change by reducing greenhouse gas emissions. Diversification of energy technologies with clean and modern energy sources like renewables avoid the over‐dependence on fossil fuels for agricultural purposes. Trade policies can stimulate flows of technology and investment opportunities for specialization in production and economies of scale. Hence, the consideration of policies that boost agricultural sector productivity and create an efficient market for international trade in Africa will help in improving livelihoods.     

Nikinake: the mobilization of labour and skill development in rural Ethiopia

A public mobilization approach known as nikinake drives implementation and technology upscaling in Ethiopia's agricultural extension. This study investigates and describes the processes and effectiveness of nikinake as an extension method used for natural resource management (NRM). The paper draws on empirical field research conducted in Oromia and the southern region of Ethiopia by looking at nikinake in the context of a watershed management campaign in 2015 and 2016. Nikinake is used as an approach to mobilize the public and to promote the skills of farmers and development actors. In principle, the implementation of NRM is voluntary; however, it is largely planned top‐down and enforced through state actors and informal institutions. This study suggests effective integration of social mobilization with reliable extension and a paradigm shift in emphasis from spatial coverage to an effective outcome. Additionally, sustainability and scalability of NRM interventions could be ameliorated by improving experts’ technical skills, raising farmers’ awareness, improving an incentive system, building trust, and better integrating past watershed management and future planning activities. We reflect on the significance of the nikinake experience in Ethiopia for a broader theory of extension‐as‐mobilization for rural development. From the Ethiopian case, a more general recommendation emerges for extension‐as‐mobilization schemes. For long‐term development, it is worthwhile to consider the fit between yearly campaigns as ad hoc project organizations and the existing pattern of actors and institutions responsible for rural development.     

重庆市农业环境质量安全现状与防治对策

对重庆市农业环境质量安全现状进行了研究分析，提出了充分利用环境资源比较优势，进行农业生产布局和农业结构调整；加强城郊区农业生态环境保护和污染的治理；合理施用农药化肥，防止农产品农药残留和硝酸盐污染；加强全市农业环境与农产品质量安全监测体系建设，开展预警监测；加强三峡库区农业面源污染防治；进一步开展农业环境优先污染物的控制研究等防治对策。     

Irrigated Agriculture and Wildlife Conservation: Conflict on a Global Scale

/ The demand for water to support irrigated agriculture has led to the demise of wetlands and their associated wildlife for decades. This thirst for water is so pervasive that many wetlands considered to be hemispheric reserves for waterbirds have been heavily affected; for example, the California and Nevada wetlands in North America, the Macquarie Marshes in Australia, and the Aral Sea in central Asia. These and other major wetlands have lost most of their historic supplies of water and some have also experienced serious impacts from contaminated subsurface irrigation drainage. Now mere shadows of what they once were in terms of biodiversity and wildlife production, many of the so-called "wetlands of international importance" are no longer the key conservation strongholds they were in the past. The conflict between irrigated agriculture and wildlife conservation has reached a critical point on a global scale. Not only has local wildlife suffered, including the extinction of highly insular species, but a ripple effect has impacted migratory birds worldwide. Human societies reliant on wetlands for their livelihoods are also bearing the cost. Ironically, most of the degradation of these key wetlands occurred during a period of time when public environmental awareness and scientific assertion of the need for wildlife conservation was at an all-time high. However, designation of certain wetlands as "reserves for wildlife" by international review boards has not slowed their continued degradation. To reverse this trend, land and water managers and policy makers must assess the true economic costs of wetland loss and, depending on the outcome of the assessment, use the information as a basis for establishing legally enforceable water rights that protect wetlands from agricultural development.