Soil erosion in developing countries: A politicoeconomic explanation

Soil erosion is accelerating in developing countries of Asia, Africa, and Latin America. It has threatened the livelihood of millions of peasants, for agriculture is their economic mainstay. A probe into the forces causing erosion reveals that the elite’s resolve to accumulate ever more wealth and to maintain, consolidate, or expand their sociopolitical power and the necessity of the poor to fulfill their requirements of food, fuelwood, and fodder are the two major factors accelerating soil erosion. Unless the vast masses of poor people are integrated into the national mainstream through the implementation of equitable and redistributive development policies, it is impossible to control the accelerating rate of soil erosion and thus to achieve the objective of sustainable development. In this article, the phenomenon “soil erosion” is studied with the sol e focus on causation through anthropogenic factors.     

Ethics,ecology and development: Styles of ethics and styles of agriculture

This paper proposes to test the ethical acceptability of four styles of agricultural resource management: (1) contemporary industrial integrated systems agriculture, (2) modern industrial input dependent agriculture, (3) continuous traditional agriculture and (4) non-continuous (or swidden) traditional agriculture. The test of ethical acceptability is whether or not these styles of agricultural resource management embrace or are even compatible with that pattern of practical reasoning and interaction among ethical agents which we have independent theoretic grounds for preferring. The preferred sorts of practical reasoning and interaction are those which we find operating in ethical theories which are strongly committed to letting the discretion of ethical agents construct what is right for them to do. Thus the discussion distinguishes several different strengths of constructivist ethics relating them to the work of John Rawls, Immanuel Kant and Onora O'Neill. Then it argues for the theoretic preferability of one particular strength of constructivist ethic. The paper winds up by arguing that only traditional continuous agriculture embodies the preferred sort of practical reasoning and interaction among ethical agents. Further, I argue that this is the only style of agriculture which can embody such reasoning and patterns of interaction. Thus, as we consider the role of agriculture in our plans of international development, we have one reason to try to favor traditional continuous agriculture. To do otherwise would ignore the ethical superiority of the practical reasoning and patterns of interaction of traditional agriculturalists.     

LOW-INPUT AGRICULTURE AS A GROUND WATER PROTECTION STRATEGY1

ABSTRACT: Protection of ground water quality is of considerable importance to local, state, and federal governments. This study uses a 15-year mathematical programming model to evaluate the effectiveness of low-input agriculture, under alternative policy scenarios, as a strategy to protect ground water quality in Richmond County, Virginia. The analysis considers eight policy alternatives: cost-sharing for green manures, two restrictions on atrazine applications levels, chemical taxation, a restriction on potential chemical and nitrogen levels in ground water only and in surface and ground water, and two types of land retirement programs. The CREAMS and GLEAMS models were used to estimate nitrate and chemical leaching from the crop root zone. The economic model evaluates production practices, policy constraints, and water quality given a long-term profit maximizing objective. The results indicate that low-input agriculture alone may not be an effective ground water protection strategy. The policy impacts include partial adoption of low-input practices, land retirement, and the substitution of chemicals. Only mandatory land retirement policies reduced all chemical and nutrient loadings of ground water; however, they did not promote the use of low-input agricultural practices.     

充分利用平行岭谷区光热资源发展立体农业

本文通过对川东平行岭谷区光、热、水分资源的立体特性分析，提出调整农业结构和作物布局，发展立体农业的几点建议。     

Clarifying the definition ofSustainable agriculture

A number of distinct definitions ofsustainable agriculture have been proposed. In this paper we criticize two such definitions, primarily for conflating sustainability with other objectives such as economic viability and ecological integrity. Finally, we propose and defend a definition which avoids our objections to the other definitions.     

硝化抑制剂硝基吡啶在农业和环境保护中的应用

讨论了硝化抑制剂硝基吡啶的作用机理,综述了硝基吡啶对农作物营养元素吸收、作物品质、作物产量、植物病害和毒害的影响,以及该硝化抑制剂对氮肥的淋溶损失和气态损失的影响.     

QUANTIFICATION OF THE WATER BUDGET AND NUTRIENT LOADING IN A SMALL PEATLAND1

ABSTRACT: Few water budgets exist for specific types of wetlands such as peatlands, even though such information provides the basis from which to investigate linkages between wetlands and upland ecosystems. In this study, we first determined the water budget and then estimated nutrient loading from an upland farm field into a 1.5 ha, kettle-block peatland. The wetland contains highly anisotropic peat and has no distinct, active layer of groundwater flow. We estimated the depth of the active layer using Fick's law of diffusion and quantified groundwater flow using a chemical mass balance model. Evapotranspiration was determined using MORECS, a semi-physical model based on the Penman-Monteith approach. Precipitation and surface outflow were measured using physical means. Groundwater provided the major inflow, 84 percent (44,418 m³) in 1993 and 88 percent (68,311 m³) in 1994. Surface outflow represented 54 percent (28,763 m³) of total outflows in 1993 and 48 percent (37,078 m³) in 1994. A comparison of several published water budgets for wetlands and lakes showed that error estimates for hydrologic components in this study are well within the range of error estimates calculated in other studies. Groundwater inflow estimates and nutrient concentrations of three springs were used to estimate agricultural nutrient loading to the site. During the study period, nutrient loading into the peatland via groundwater discharge averaged 24.74 kg K ha^-1, 1.83 kg total inorganic P ha^d, and 21.81 kg NO₃-N ha^-1.     

A role-playing game as a tool to facilitate social learning and collective action towards Climate Smart Agriculture: Lessons learned from Apuí, Brazil

Addressing the global challenges of climate change (CC), food security and poverty alleviation requires enhancing the adaptive capacity and mitigation potential of land use systems. To this end, Climate Smart Agriculture (CSA) aims to identify land use practices that sustainably increase productivity, enhance climate change (CC) adaptation and contribute to CC mitigation. A transition towards CSA requires technical, but also socio-institutional changes, for improved smallholder agricultural systems. Such changes may be triggered by stakeholder participation processes that stimulate social learning and collective action. This article evaluates whether a role-playing game (RPG) is an effective participatory tool to encourage social learning and collective action among local stakeholders towards adoption of CSA strategies. We designed and implemented an RPG with three groups of farmers in Apuí (Southern Amazonas), evaluating the game’s impact on social learning by interviewing each farmer before and after the RPG. Our findings show that the RPG induced not only technical learning, but also socio-institutional learning and engagement for collective action, though outcomes varied between different RPG sessions and among farmer participants.     

洞庭湖区农业环境与湖垸农业可持续发展模式

围湖垦殖形成了洞庭湖区湖垸农业形式,湖垸农业的形成加速了湖区人口的增长,人口的压力也促进了围垦。不断的围湖垦殖使耕地面积迅速增加。由于湖泊面积减少,湖垸农业处于外洪内涝的环境中。归纳了洞庭湖区的农业环境问题：洪涝灾害发生频率加大;水面减少,生物多样性降低;环境污染严重,湿地生态功能衰退;土壤退化和潜育化严重;血吸虫病死灰复燃等。结合已有经验,提出了湖垸农业可持续发展模式：认真实施生态保护工程,减少泥沙淤积;调整湖垸农业结构,建立可持续发展生态农业模式：避灾、减灾模式、水生经济植物模式、工业原料作物模式、林农复合经营模式、湖洲草地草食畜禽模式、麻基（油菜）渔塘农业模式等。     

我国现代农业发展路线与发展战略

在当前,我国现代农业发展背负着重大包袱,面临着日益激烈的国际竞争,大力发展现代农业成为迫切需要.世界农业形势出现了新的变化,集中体现在理念创新、科技创新和制度创新.结合我围发展现代农业的国情,构建一个以产业理念创新为核心,以科技创新为动力,以组织保障制度创新为支撑的现代农业发展战略框架,描绘一个30年跨度的我国农业发展路线图,具有积极的理论意义与现实意义.