江苏太湖地区农业耕作制度变化及其对地表水土环境的影响

农业耕作制度变化及其环境效应是国内外广泛关注的学术前沿问题。近60 a来,江苏太湖地区农业耕作制度发生较大变化,主要表现在种植制度从偏重粮食生产转向粮经作物协调发展,用地作物增多而养地作物减少,作物品种经历了改进与优化过程,作物熟制经历了从“双三制”恢复到两熟制。施肥种类从有机肥为主转变为完全施用化肥,氮磷钾肥投入比例从长期严重失调发展到逐渐趋于协调。在总结近60 a来江苏太湖地区农业耕作制度变化特征的基础上,〖JP2〗分析了农业耕作制度变化对地表水土环境的影响,并提出了今后需要进一步关注的研究方向     

Impact of policies favouring organic inputs on small farms in Karnataka, India: a multicriteria approach

Over 56% of the population of Karnataka state in India depends on agriculture for its livelihood. A majority of these are small and marginal farmers, with land under 2?ha, responsible for nearly half the food production in the state. The increasing rate of farmers’ suicides in the state is reportedly fuelled among others, by increasing input costs, crop failure and accumulating debt. This triggered several policy measures, intended to improve the sustainability of farm livelihoods including those promoting organic practices in farming. The paper presents the results of a multicriteria analysis conducted to comprehend the effects of two different practice–policy scenarios on smallholders in Karnataka—one scenario ‘with policy’ (WP) to support organic agricultural practices and the other a ‘business as usual’ (BAU) scenario that continues to stress on market-based, synthetic inputs for cultivation. The paper integrates results from quantitative and participatory techniques to compare and project effects on ecological, economic and socio-cultural indicators. Ecological and economic indicators in WP are projected to be significantly higher than BAU in a majority of the study sites, while socio-cultural indicators show mixed outcomes, depending on regional and social characteristics. Across the study sites, small and rain-fed farms are benefitted better in WP compared to large and irrigated farms, respectively. Among small and rain-fed farms, soil fertility, water quality, agro-diversity, net income and freedom from indebtedness improve considerably, while there is slight reduction in collective activities and no perceivable change in land-based subsistence.     

Social and environmental trade-offs in tree species selection: a methodology for identifying niche incompatibilities in agroforestry

Natural resource degradation in highland regions is of increasing concern to the global community due to its role in aggravating poverty and the loss of environmental services to local and downstream users. The integration of trees into smallholder farming systems has been promoted as a means to enhance rural livelihoods while reversing the degradation of soil, water, biodiversity and related environmental services. Yet in addition to these benefits, negative impacts of trees on certain stakeholders or system components have also accompanied such efforts—suggesting that important trade-offs accompany afforestation. This paper presents a methodology for diagnosing problems stemming from cultivation of certain tree species in specific landscape niches. Data derived from the application of this methodology in two sites in the eastern African highlands are presented. Participatory diagnoses of landscape-level problems suggest that the negative impact of trees on water resource availability and crop yield are of critical concern to smallholder farmers. Ethnoecological data highlight the properties of different tree species that determine their suitability to specific farm and landscape niches. These data point to important opportunities for more socially- and environmentally-optimal integration of indigenous and exotic tree species into agricultural landscapes, and highlight the critical importance of local knowledge in forging solutions appropriate to contemporary realities.     

“Organic is More of an American Term … We Are Traditional Farmers”: Discourses of Place-based Organic Farming,Community, Heritage,and Sustainability

The following study looks at how traditional, organic, cooperative farmers starting a new farming cooperative in the US Southwest communicate about their farming as a set of (sustainable) cultural practices. The study draws on environmental communication theory, the theory of the coordinated management of meaning, and Vandana Shiva’s three-tiered economic model to construct a communication-based framework through which to view farmers’ stories about sustainability. This framework is productive, showing how some Nuevo Mexicano farmers (and others) orient toward farming, sustenance, and human-nature relationships through community, family, heritage, and education. Moreover, in addition to a conceptualization of sustainability as specific practices for nurturing and enduring in environments, communities, and organizations/institutions, sustainability can be understood as embedded ecocultural and historical experience with cross-cultural parallels in land-based communities. This study advances the ethical duty of environmental communication to better understand the ways in which environmental discourse and ecocultural and material realities are imbricated, as well as the call for such discursive study to be grounded in phenomenological experience of the natural world.     

长江三角洲水田保护性耕作制度的碳收集效应估算

耕作制度对农田土壤有机碳的稳定和积累作用显著,探讨耕作制度演变下农田土壤碳库动态,将有助于农田土壤碳收集的技术选择及政策制定。利用已发表的田间定位试验数据,构建不同耕作制度下长江三角洲水田耕层土壤有机碳密度的估算模型。依据该区近20多年来耕作制度演变动态,对保护性耕作制度的土壤碳收集效应进行了初步估算。结果表明,油菜面积的扩大、小麦的少免耕和作物秸秆的还田分别约增加土壤耕层有机碳0.94 Tg、2.76 Tg和3.95 Tg,其中以麦稻复种转向油稻复种的单位面积碳收集效应为最高。最后,就碳收集效应估算的方法进行了相关讨论,并就土壤碳收集研究和如何提高土壤碳收集潜力提出了一些建议。     

Decision support model to select crop pattern for sustainable agricultural practices using fuzzy MCDM

The crop pattern has a significant impact on the feasibility of sustainable agricultural practices. Selected crop pattern influences environmental and economic condition and affects sustainability profoundly in agricultural practices. Hence, a careful intervention is required in the selection of an optimal crop pattern for sustainable agricultural practices. Selection of a particular set of crop pattern depends on many criteria that may vary from place to place thus pose challenges in deciding an optimum crop pattern. The present research focuses on the crop selection pattern in Indian environment that considers comprehensive criteria related to sustainable farming practices. Based on the in-depth review of the literature and experts opinion, comprehensive criteria related to sustainable farming practices for Ravi season crop are identified. Total twelve criteria covering socioeconomic conditions, soil and water conditions, environmental and climatic conditions are earmarked and taken into account for eight most commonly grown crops in Ravi season and later on modeled to determine the crop pattern for most needed sustainability. A fuzzy-based multi-criteria decision-making model has been developed considering the Indian farming system. The scarce resources availability to Indian farmers poses many challenges to practice farming with most needed sustainability. The present research will be useful in the area of Indian farming practices in particular and global farming practices in general. It will also help stakeholders in their cost effective decision making for better crop productivity leading to sustainable farming practices. Additionally, the state policy makers will be able to formulate effective state driven sustainable farming policy to enhance its stake in gross domestic product to become self-reliance.     

Assessing the impact of policy-driven agricultural practices in Karnataka, India

The classical approach of assessing sustainability with respect to its three underlying pillars, ecological, economic, and social, is adopted in this paper, with an added emphasis on estimating the simultaneous effects of each pillar on the other two. The paper assesses the impact of policy-driven changes in cultivation practices in five districts in the south-western Indian state of Karnataka. A comparative statics analysis using a simultaneous equations model is developed to capture the stability of each pillar into the future and their concurrent interactive impacts and trade-offs. Ecological and economic impacts of policies favoring organic farming are estimated to be uniformly significant and positive in the study districts. However, the impact on socio-cultural criteria is subjective to the eco-regional context. Cost savings, through producing organic inputs on-farm, maximizes synchrony among the three pillars vis-à-vis sourcing these inputs from the market. With more reliance on organic inputs, better prospects are estimated for small and rain-fed farms compared to large and irrigated farms.     

Treatment of olive mill effluents Part I. Organic matter degradation by chemical and biological processes--an overview

Olive mill effluents constitute a serious environmental problem in the Mediterranean Sea region due to the unique features associated with this type of agro-waste (i.e. seasonal and localized production, high and diverse organic load, low flow rates). Therefore, it is not surprising that research efforts have been directed towards the development of efficient treatment technologies including various physico-chemical and biological processes. This work reviews recent advances regarding olive mill effluent treatment with emphasis given on biological and chemical degradation processes.     

Environmental Implication of Intensive Farming Practices on North China Plain

1 INTRODUCTION Growing pressure on the land of North China Plain (NCP - a food bowl of the country, has made many of th traditional farming practices increasingly difficult to sustain such as manuring, composting, mulching, legume-based rotations, field levelling and fertilizing with mud from rivers and canals. The pressure on the farmlands has also led to a decrease in farm sizes and shortened fallow periods To cope with this pressure on the land and to maintain its fertility, farmers …     

转型期中国耕地非农化与土地退化的实证分析

改革开放以来．伴随着国民经济的快速发展．中国的耕地非农化速度也在不断加快。并由此产生了大量的社会和环境问题。本文从人类土地利用行为变化的角度提出了分析耕地非农化对土地退化影响的基本思路：然后基于这一思路．并结合对全国层面统计数据的计量分析．深入探讨了转型期中国的耕地非农化对土地退化的影响：研究表明由耕地非农化所引致的耕地开垦、耕地集约利用以及非农建设用地扩张等人们土地利用行为的变化会最终引起土地资源的退化：包括水土流失和土地沙化的加剧、土壤质量的退化以及土地污染的加剧等。     

Economic potential for conversion to organic farming: a net present value analysis in the East Mau Catchment,Nakuru, Kenya

This paper discusses the economic potential in terms of income changes that may result from conversion to low-external-input agriculture (LEIA) organic farming in a Kenya’s catchment area. A spreadsheet model applying the gross margin and net present value analysis was developed to estimate economic returns to labour and land of alternative smallholder cropping systems in the East Mau Catchment. The income and costs over a 10-year horizon associated with current cropping practices of a typical farm household cultivating 1.12 hectares of maize–bean intercrop, Irish potato, carrots, tomatoes, cabbages and kales mix were characterized based on field work conducted in 2008–2010. An “average” smallholder LEIA organic farm was simulated based on the conventional one, and its income discounted. A comparison was then made of the two farm types. Results indicate annual net present value returns to cropped land average Ksh 21,878/ha ($ 267/ha) and Kshs 22,561/ha (€ 275/ha) in 2010 values for conventional and prototype LEIA organic farming systems, respectively. Net returns are particularly sensitive to crop yields and price and cost of fertilizers and seeds. Further efforts should be made to provide an economic analysis of other LEIA organic farming practices such as composting, double digging and agroforestry in terms of additional labour costs resultant. The model can be extended to build more scenarios on the role of price premiums. Additionally, further research should be done to exploit the socio-demographic factors affecting the adoption of low-external-input systems.     

Environmental Implication of Intensive Farming Practices on North China Plain

Abstract

The current pressure on production resources of North China Plain, such as land and water to feed the growing population, necessitates the assessment of the sustainability of farming practices. This study focuses on the sustainability of farming practices related to groundwater and soil fertility management. The assessment is based on selected site-specific key indicators and their established threshold limits. The current farming practices in the study area are clearly unsustainable. Only about 6% of the surveyed farm households practice sustainable farming. The study stresses that farming practice, which is economically sustainable, should not be promoted at the cost of environment. Holistic strategies need to be developed and implemented that aim at balanced use of inputs, which satisfy both productivity and environmental concerns.     

Motivations for organic farming in tourist regions: a case study in Nepal

An increasing number of individuals and businesses involved in the tourism industry have begun activities related to organic farming and organic agro-products not only in Europe and North America but also in developing countries in Asia. Both organic farming and rural tourism are considered important to socially and economically sustainable rural development. The influences on the establishment of or conversion to organic farming have been much discussed in Europe but not in developing countries. This study focuses on Nepal, where small-scale organic farming occurs in tourism areas, and qualitatively reveals the motivations for organic farming and other factors related to its adoption. It was found that the reasons for introducing organic farming practices varied with the timing of their adoption. Additionally, the kinds of organic-related activities adopted varied depending on how the individual adopter first encountered the term “organic farming.” However, all individuals involved in organic farming shared some common motivations, such as desires for personal health, quality produce and rural development.     

农业贸易政策环境影响评价的案例研究

随着国际贸易自由化程度的提高,贸易与环境问题越来越引起人们的重视。对贸易政策进行环境影响评价。指导贸易政策的制定。是解决贸易所带来的环境问题的重要途径。了解中国入世后一系列的农业政策调整会在多大程度上影响环境。对于新的政策决策具有指导意义。本文在总结贸易政策环境影响评价研究步骤和方法的基础上。对农业贸易政策环境影响评价的特点进行讨论,并以河北省迁安市小麦种植业为例,进行农业贸易政策环境影响评价的案例研究。由于农业贸易政策直接作用于农业生产经营活动。再通过农业生产经营等活动间接地影响环境质量状况。本文借助转移矩阵方法进行分析评价。     

Tools to study the degradation and loss of the N-phenyl carbamate chlorpropham — A comprehensive review

Chlorpropham (CIPC) was introduced in 1951 and is a primary N-phenyl carbamate belonging to a group of pesticides known as carbamates which are estimated to account for 11% of the total insecticide sales worldwide. They were considered less toxic than organochlorines due to their easier breakdown but, subsequent concerns regarding the environmental impact and their breakdown products have shown them to be environmental toxins and toxic and/or carcinogenic for humans. CIPC is used in growing crops to control weeds and also as a sprout suppressant on crops during long-term storage and while its degradation has been studied and rates quoted these vary greatly. Here published rates of degradation by hydrolysis, biolysis, photolysis and thermal processes are reviewed as well as data on partitioning in air, water and soil. In addition the details of the experimental procedures are reviewed and compared showing how the half-lives and partitioning coefficients have been calculated leading to an understanding of how such vastly different values are achieved. The legislation regarding the use of CIPC and its maximum residue level is also discussed particularly in reference to recent European Commission (EC) legislation. In view of the fact that analytical data on the breakdown of CIPC play an important role in decision-making by regulatory agencies, the authors feel that it is time for an up-to-date review of the data available, including very recent developments in methodology.     

Markets and climate are driving rapid change in farming practices in Savannah West Africa

Agricultural practices have constantly changed in West Africa, and understanding the factors that have driven the changes may help guide strategies to promote sustainable agriculture in the region. To contribute to such efforts, this paper analyzes drivers of change in farming practices in the region using data obtained from surveys of 700 farming households in five countries (Burkina Faso, Ghana, Mali, Niger and Senegal). The results showed that farmers have adopted various practices in response to the challenges they have faced during the last decade. A series of logit models showed that most changes farmers made to their practices are undertaken for multiple reasons. Land use and management changes including expanding farmed areas and using mineral fertilization and manure are positively related to perceived changes in the climate, such as more erratic rainfall. Planting new varieties, introducing new crops, crop rotation, expanding farmed area and using pesticides are positively associated with new market opportunities. Farm practices that require relatively high financial investment such as use of pesticides, drought-tolerant varieties and improved seeds were positively associated with the provision of technical and financial support for farmers through development projects and policies. Changes in markets and climate are both helping to promote needed changes in farming practices in West Africa. Therefore, policies that foster the development of markets for agricultural products, and improved weather- and climate-related information linked to knowledge of appropriate agricultural innovations in different environments are needed.     

长期施肥对小麦—玉米轮作红壤抗蚀性的影响

为探讨不同施肥处理对红壤旱地土壤理化性状和抗蚀性影响,以长期定位施肥试验小区为研究对象,研究了CK（荒草地）、T1（不施肥）、T2（施有机肥）、T3（施氮磷钾肥）和T4（氮磷钾肥与秸秆配施）5种处理的土壤理化性状及土壤抗蚀性。结果表明：（1）荒草地开垦后,土壤容重降低,土壤孔隙度和含水量升高;相较于不施肥,施肥提高土壤有机质含量、改善土壤物理性质作用更为明显;（2）衡量不同施肥处理土壤抗蚀性的2个最佳指标为>0.25 mm水稳性团聚体含量和结构破坏率;（3）使用主成分分析综合指数表示不同处理土壤抗蚀性依次为：T2>CK>T3>T4>T1,荒草地开垦后,耕种会降低土壤抗蚀性,但施肥能略微提升土壤抗蚀性,而施有机肥提升最为明显。研究结果可为区域内农业生态系统持续发展及农田水土保持工作提供依据。     

Land treatment: A viable and successful method of treating petroleum industry wastes

Land treatment is an environmentally attractive alternative for the disposal of petroleum refinery wastes. Diverse populations of soil microorganisms degrade waste oil and other organic compounds through a series of complex reactions to yield carbon dioxide, water, and innocuous byproducts. Approximately one-half of the disposable volume of oily sludges are currently land treated at more than 100 sites across the United States under a variety of soil and climatic conditions. Maximization of biodegration rates requires an optimization of management practices which stimulate aerobic microbial populations in the soil. These management practices include addition of fertilizer, judicious waste application, and frequent cultivation. Off-site migration of oily waste constituents that would endanger groundwater quality has not been observed in several field and laboratory studies. The leached residuals are apparently adsorbed, assimilated, or inactivated in the upper soil horizons. A prudent management system, however, requires an individually tailored monitoring system with dual objectives for an early detection of off-site waste constituent transport and for evaluating the performance of waste biodegradation processes. A cost comparison for the disposal of oily wastes by currently available technologies indicates that land treatment is the most economical option.     

The effect of fire on soil organic matter--a review

The extent of the soil organic carbon pool doubles that present in the atmosphere and is about two to three times greater than that accumulated in living organisms in all Earth's terrestrial ecosystems. In such a scenario, one of the several ecological and environmental impacts of fires is that biomass burning is a significant source of greenhouse gases responsible for global warming. Nevertheless, the oxidation of biomass is usually incomplete and a range of pyrolysis compounds and particulate organic matter (OM) in aerosols are produced simultaneously to the thermal modification of pre-existing C forms in soil. These changes lead to the evolution of the OM to "pyromorphic humus", composed by rearranged macromolecular substances of weak colloidal properties and an enhanced resistance against chemical and biological degradation. Hence the occurrence of fires in both undisturbed and agricultural ecosystems may produce long-lasting effects on soils' OM composition and dynamics. Due to the large extent of the C pool in soils, small deviations in the different C forms may also have a significant effect in the global C balance and consequently on climate change. This paper reviews the effect of forest fires on the quantity and quality of soils' OM. It is focused mainly on the most stable pool of soil C; i.e., that having a large residence time, composed of free lipids, colloidal fractions, including humic acids (HA) and fulvic acids (FA), and other resilient forms. The main transformations exerted by fire on soil humus include the accumulation of new particulate C forms highly resistant to oxidation and biological degradation including the so-called "black carbon" (BC). Controversial environmental implications of such processes, specifically in the stabilisation of C in soil and their bearing on the global C cycle are discussed.     

Agronomic adaptation strategies under climate change for winter durum wheat and tomato in southern Italy: irrigation and nitrogen fertilization

Agricultural crops are affected by climate change due to the relationship between crop development, growth, yield, CO₂ atmospheric concentration and climate conditions. In particular, the further reduction in existing limited water resources combined with an increase in temperature may result in higher impacts on agricultural crops in the Mediterranean area than in other regions. In this study, the cropping system models CERES-Wheat and CROPGRO-Tomato of the Decision Support System for Agrotechnology Transfer (DSSAT) were used to analyse the response of winter durum wheat (Triticum aestivum L.) and tomato (Lycopersicon esculentum Mill.) crops to climate change, irrigation and nitrogen fertilizer managements in one of most productive areas of Italy (i.e. Capitanata, Puglia). For this analysis, three climatic datasets were used: (1) a single dataset (50?km?×?50?km) provided by the JRC European centre for the period 1975–2005; two datasets from HadCM3 for the IPCC A2 GHG scenario for time slices with +2°C (centred over 2030–2060) and +5°C (centred over 2070–2099), respectively. All three datasets were used to generate synthetic climate series using a weather simulator (model LARS-WG). Adaptation strategies, such as irrigation and N fertilizer managements, have been investigated to either avoid or at least reduce the negative impacts induced by climate change impacts for both crops. Warmer temperatures were primarily shown to accelerate wheat and tomato phenology, thereby resulting in decreased total dry matter accumulation for both tomato and wheat under the +5°C future climate scenario. Under the +2°C scenario, dry matter accumulation and resulting yield were also reduced for tomato, whereas no negative yield effects were observed for winter durum wheat. In general, limiting the global mean temperature change of 2°C, the application of adaptation strategies (irrigation and nitrogen fertilization) showed a positive effect in minimizing the negative impacts of climate change on productivity of tomato cultivated in southern Italy.