FSWM: A hybrid fuzzy-stochastic water-management model for agricultural sustainability under uncertainty

A hybrid fuzzy-stochastic water-management (FSWM) model is developed for agricultural sustainability under uncertainty, based on advancement of a multistage fuzzy-stochastic quadratic programming (MFSQP) approach. In MFSQP, uncertainties presented in terms of fuzziness and randomness can be incorporated within a multilayer scenario tree, such that revised decisions are permitted in each time period based on the realized values of the uncertain events. Moreover, fuzzy quadratic terms are used in the objective function to minimize the variation of satisfaction degrees among the constraints; it allows an increased flexibility in controlling the system risk in the optimization process. Results of the case study indicate that useful solutions for the planning of agricultural water management have been obtained. In the FSWM model, a number of policies for agricultural water supply are conducted. The results obtained can help decision makers to identify desired water-allocation schemes for agricultural sustainability under uncertainty, particularly when limited water resources are available for multiple competing users.     

A field practical approach for assessing biophysical sustainability of alternative agricultural systems

Participatory research and farmer-led extension principles are employed to conduct meaningful monitoring and evaluation while working within the constraints encountered in the field by farmers and rural agents. This assessment method is characterized as Field Practical, that is, it is (1) quick, (2) inexpensive, (3) easily applied, (4) of direct and immediate relevance, and (5) a tool for stimulating project productivity. It harmonizes external expertise with local experience for biophysical sustainability assessment of proposed production alternatives in the context of the local agricultural system. This is accomplished via a Likert rating survey based on locally defined criteria and indicators and has two outputs: (1) a Summary Measure based on weighted average ratings giving indication of overall patterns of contributions to the biophysical sustainability of the agricultural system and (2) Frequency Distribution Matrices for more detailed analyses of the data. Statistical tests for differences add discriminatory power. This assessment was applied in northern Ecuador, but could be adapted to other locations.     

The impact of water and agriculture policy scenarios on irrigated farming systems in Italy: An analysis based on farm level multi-attribute linear programming models

The objective of this paper is to evaluate the impacts of agriculture and water policy scenarios on the sustainability of selected irrigated farming systems in Italy, in the context of the forthcoming implementation of the directive EC 60/2000. Directive EC 60/2000 (Water Framework Directive) is intended to represent the reference norm regulating water use throughout Europe. Five main scenarios were developed reflecting aspects of agricultural policy, markets and technologies: Agenda 2000, world market, global sustainability, provincial agriculture and local community. These were combined with two water price levels, representing stylised scenarios for water policy. The effects of the scenarios on irrigated systems were simulated using multi-attribute linear programming models representing the reactions of the farms to external variables defined by each scenario. The output of the models consists of economic, social and environmental indicators aimed at quantifying the impact of the scenarios on different aspects of sustainability relevant for irrigated farming systems. Five Italian irrigated farming systems were considered: cereal, rice, fruit, vegetables and citrus. The results show the diversity of irrigated systems and the different effects that water pricing policy may produce depending on the agricultural policy, market and technological scenarios. They also highlight a clear trade-off between socio-economic sustainability and environmental (water, nitrogen, pesticide) sustainability. Water pricing will have, in most cases, less impact than agricultural markets and policy scenarios, though it appears to be an effective instrument for water regulation in the least intensive irrigated systems considered. This emphasises the need for a differentiated application of the Water Framework Directive at the local level as well as a more careful balance of water conservation, agricultural policy and rural development objectives.     

不同生计策略选择对农户多维贫困的影响研究

探讨生计策略选择对降低农户多维贫困有重要意义。基于2019年新疆维吾尔自治区塔城市额敏县305户农户的调查数据,分析不同生计策略选择对农户多维贫困的影响。首先基于可行能力理论,运用A-F方法测算出多维贫困指数,识别脱贫农户的多维贫困。其次,采用倾向得分匹配法,分析不同生计策略对多维贫困的缓解效应。最后基于生计可持续框架,采用Probit回归模型,探讨选择不同生计策略的农户所拥有的生计资本对农户多维贫困的影响。实证结果表明,选择非农主导型生计策略的农户更能缓解农户的多维贫困,平均处理效应为-18.07%。此外人力资本对选择3个不同的生计策略农户的多维贫困均有缓解,金融资本有利于缓解农业型农户和非农业型农户的多维贫困,物质资本不利于缓解兼业型农户的多维贫困。     

冯家山水库供水持续性评价

结合可持续发展理念与风险分析的理论和方法,选取可靠性、弹性、脆弱性、均方差及最大缺水率等5个性能指标为持续性指标,以冯家山水库为研究对象,针对生活、工业、生态环境、农业灌溉等水库用水户,合理选取性能指标构建持续性指标,对其持续性进行了评价;并用这4个用水户作为用水群的组成构建群持续性指标对水库供水持续性进行了评价.冯家山水库供水持续性评价结果表明,在现状情形下,水库供水持续性为35%,持续性较低;尤其农业灌溉供水持续性仅为29%.减少农业灌溉对水库需水要求的30%时,生活、工业、生态环境、农业灌溉用水户的可靠性及持续性都得到提高,此时,农业灌溉供水持续性为40%,水库供水持续性为45%,水库供水持续性得到提高.可在灌区采取一定的节水措施,以减少农业灌溉对水库的需水,提高农业灌溉用水户的持续性和水库供水持续性,降低缺水风险,促进水库的可持续发展.     

基于复合多目标方法的灌区水资源优化配置

针对传统灌区水资源多目标模型求解过程中难以兼顾多维配置要求的问题,基于目标协调度、可持续发展指数、目标实现度3个指标提出了一种复合多目标方法。为验证该方法有效性,以甘肃省黑河中游17个灌区间水资源优化配置为例,以经济效益、社会效益、生态效益为目标函数构建多目标优化模型,并分别使用传统方法与复合多目标方法进行求解。结果表明,使用复合多目标方法所获得的优化配置方案可以将灌溉水利用系数提高5.42%~7.57%。结果验证了传统多目标模型在协调多个冲突目标方面较单目标模型有显著优势,而复合多目标方法所获得的优化方案更能体现决策者对研究区域种植业发展与灌区水资源配置的多元要求。     

Prospects and problems of irrigation development in Sahelian and sub-Saharan Africa

Although many different definitions of irrigation are being used, the need for this way of agricultural intensification is rapidly increasing as the population dependent on agriculture has in many countries largely surpassed the carrying capacity of rainfed systems. However, unfortunately many donor-sponsored irrigation projects in Africa disappoint because they are generally conceived with a too short time perspective and they suffer from a series of negative characteristics. Generally there is insufficient farmer involvement in all phases of the projects, which are formulated in isolation from existing farming systems, are capital-intensive and require high-input levels (from elsewhere), focus on the hardware, neglect agricultural production and institutional weaknesses, and cannot put up the money needed to be run. Therefore, sustainability should be the main point of orientation. Important steps towards it consist in choosing activities and forms of irrigation that fit well in the farming systems, are attractive to farmers, and can be run to a very large extent by themselves without external assistance. Marketing and production support services should be included in analysis and programmes of assistance, together with institutional strengthening and adequate land tenure arrangements. Governments' involvement in operation and management can often be reduced, and the same goes for the role of the irrigation organisations. Donor involvement should be more flexible, have a longer time-perspective, be less guided by expected economic rates of return and concentrate more on how to ensure increased sustainability of irrigation projects for both the country and the farmers.     

基于三维小波变换的农机CAD模型特征提取与评价方法

为提高三维CAD模型特征提取准确度,满足农业机械制造领域CAD模型智能化检索需求,提出一种三维CAD模型的特征提取与评价方法。首先对农业机械模型库中三维模型进行平移归一化、旋转归一化、尺度归一化处理,规范化后的CAD模型进行三维离散小波变换,CAD模型经过单层三维小波变换后被表示为8个维度的频域系数子空间;然后对低频子空间LxLyLz进行二次小波变换,二层级小波变换后单个CAD模型被分解为15个特征量,采用AHP层次分析法确定不同频域空间特征量权重,以距离度量法定义含有权重系数的相似性度量值,完成不同模型间特征提取及相似性比较,计算并建立三维CAD模型频域特征索引表;最后以VS2010与Matlab 2016b为开发环境,以Open Cascade为几何造型平台,使用ESB通用模型库及农业机械零部件参数化模型库验证算法有效性。在ESB模型库中T型零件检索结果表明,在保持相同查准率条件下,本文小波变换算法排序误差更小。拨禾轮CAD模型检索结果显示,相似性评价度量方法不仅考虑模型的形态相似性,同时兼顾了应用领域语义相似性,算法实用性高。农机装配体检索实例应用结果表明,借助本文检索算法,可从海量模型库中检索出所需模型,根据实际设计要求对检索出的相似模型进行编辑和修改,可快速完成零部件模块化设计。三维小波变换检索算法查准率受小波函数性质影响,coif类小波函数具有较强的检索适用性,层次分析法能有效区分不同分解层权重,二层级小波变换能够达到现阶段机械零件模型检索精度要求。小波变换设计重用检索算法可满足模型检索设计需求,拓宽设计者设计思路,促进智能化设计。     

灌区灌溉用水时空优化配置方法

将传统的灌溉水量在作物间的优化分配模型和建立的渠系工作制度多目标优化模型与地理信息系统相集成,提出了基于空间决策支持系统的灌区灌溉用水优化配置的新方法.综合考虑了灌区内作物、土壤、气象站点、渠系布置的空间差异、年季间气象以及作物不同生育阶段对应参数的时间差异.与传统优化方法相比,该方法可根据管理者对优化精度的要求,灵活选择优化尺度,同时,简化了求解时空优化配水问题的繁琐程度,结果表现形式更加丰富.在此基础上建立的空间决策支持系统界面友好,运行效率高,可移植性和通用性强.经实例验证,优化后的配水方案与原配水方案相比较,灌溉总用水量减少296％,产量增加243％,水分生产率提高05 kg／m3,灌溉净效益增加168％.优化后配水方案具有将有限的水资源向经济价值较高作物转移的趋势.该方法为灌区灌溉用水优化配置提供了新思路.     

山西省农业机械化水平评价及空间分异

科学的对山西省不同地区农业机械化发展水平进行测度及空间差异分析,对促进全省农业机械化整体协调快速发展具有重要意义.分别采用加权综合法和改进多边形面积法对山西省及所辖11个地级市20172019年的综合机械化率进行测算,采用聚类分析的方法对各地级市进行分类,运用泰尔指数分析不同区域机械化发展水平的差异,利用ArcGIS软...     

Co-effects of climate policy and agricultural policy on regional agricultural viability in Finland

The agricultural sector has potentially a significant role in reducing greenhouse gases (GHGs). Besides providing public goods, GHG reduction offers farmers new alternatives for income generation. This is especially interesting in marginal agricultural areas, e.g., in less-favoured areas (LFA) of the European Union (EU), where significant GHG reduction potential coincides with low productivity in the production of agricultural commodities.In this study, the effects of peatland cultivation restrictions were evaluated, where the objective was to decrease GHG fluxes deriving from agricultural production. The regional role of peatlands in GHG reduction and agricultural production is also evaluated. Ceasing the agricultural use of peatlands altogether could decrease Finnish agricultural sector carbon effluents by up to 10% according to a dynamic regional sector model of the Finnish agriculture (DREMFIA). Accompanying decreases in national and even in regional agricultural incomes do not appear drastic, but locally, in some municipalities and on individual farms they may be devastating. In an alternative scenario, where perennial grass production is allowed to continue and only cultivation of annual crops is forbidden, the (negative) income effects are very low. The most notable result is that significant GHG reductions can be reached with little decrease in national agricultural incomes.The two forms of restrictions were tested in two alternative agricultural policy settings: Agenda 2000 and the EU Common Agricultural Policy (CAP) reform agreed in Luxembourg on 26th June 2003. These two agricultural policy alternatives are connected with both of the aforementioned climate policy alternatives and resulting scenarios are evaluated in the simulation. The simulation provides the second main result, which says that it is not so much the climate policy which determines aggregate agricultural production and income, but rather it is the general agricultural policy framework setting the stage.     

深圳不同植被类型城市土壤团聚体组成与分形特征

采用干筛法和湿筛法测定了深圳市乔木、灌木、草地植被绿地土壤团聚体粒径质量分布,并基于分形理论研究了土壤团聚体分形特征。结果表明,①乔木、灌木、草地之间土壤>0.25mm粒级团聚体、平均质量直径及土壤分形维数均差异显著;土壤团聚体稳定性总体表现为草坪绿地>乔木绿地>灌木绿地。②土壤非稳性团聚体分形维数、>0.25mm粒级团聚体以及平均质量直径之间均极显著相关;水稳性团聚体分形维数、>0.25mm粒级团聚体、破坏率以及平均质量直径之间均极显著相关。植被类型显著影响城市绿地土壤团聚体分布及其分形特征。     

Integrated agricultural research and crop breeding: Allelopathic weed control in cereals and long-term productivity in perennial biomass crops

Future agricultural research will need to increasingly integrate ecological, physiological and molecular methods, in order to understand agricultural crops in situ and their interaction with the environment as well as organisms impacting on their long-term health and productivity (‘agricultural eco-genomics’). The need for integration will increasingly implicate on crop breeding strategies for most agricultural systems. In this paper, implications are highlighted for two contrasting areas of agricultural research related to sustainable crop production: first, the possibilities to utilize crop allelopathic activity to suppress weeds as an alternative to chemical weed control; and second the increasing interest to environmentally friendly and sustainable produce perennial energy crops on agricultural land. ‘Sustainability’ in agriculture is difficult to define unequivocally, but frequently implies the increased utilization of ecological processes. Breeding strategies towards increased utilization of allelopathic crops require initially the integration and verification of allelopathic processes in various agricultural contexts, because there is currently great uncertainty about the predictable operation of allelopathic activity in different ecological contexts. Breeding programs for future biomass crops, most promising are perennials such as Salix, would greatly benefit from the integration of ecological information affecting long-term productivity, e.g., eco-physiological growth determinants at stand level and the biological control of pests. Agricultural eco-genomics could facilitate a compromise between intensive agriculture and the frequently expressed demand for greater sustainability in agriculture.     

土地利用方式对喀斯特峡谷区土壤水稳性团聚体的影响

【目的】全面评价土地利用方式对喀斯特峡谷区土壤结构退化的影响。【方法】采用空间代替时间的方法,开展了不同土地利用方式对土壤水稳性团聚体分布特征及稳定性的研究。【结果】①不同土地利用方式均以>0.25 mm粒径水稳性团聚体为主,其量变化、MWD、GMD均表现为林草间作地>荒草地>退耕还草地>耕地;②在不同土层中,不同土地利用方式土壤水稳性团聚体量总体上随粒径的减小呈先增加后减少再增加的变化趋势,其中0~20 cm土层,土壤各粒级水稳性团聚体量分布及稳定性差异具有一定显著相关性,20 cm至母质层差异不显著;③5 mm粒径团聚体成为土壤团聚体从微团聚体向大粒径团聚体团聚化过程中关键的临界点;④GMD可以作为喀斯特峡谷区整个剖面土壤水稳性团聚体稳定性评价指标。【结论】林草间作模式能够增强喀斯特峡谷区土壤结构的稳定性,对防止土壤结构退化具有重要作用。     

Can irrigation be sustainable?

Globally, about 10 Mha of agricultural land is lost annually due to salinisation, of which about 1.5 Mha is in irrigated areas. While some climate and management aspects are common to semi-arid regions, the detailed mechanisms and options to secure ecological sustainability and economic viability may vary considerably from case to case. This paper applies a whole of system-water balance to compare irrigation in three semi-arid regions suffering from similar sustainability issues: Rechna Doab (RD), Pakistan; the Liuyuankou irrigation system (LIS), China; and Murrumbidgee irrigation area (MIA), Australia. Soil salinity, lack of adequate water resources and groundwater management are major issues in these areas. The MIA and LIS irrigation systems also suffer from soil salinity and low water-use efficiency issues. These similarities occur in spite of very different climatic and underlying hydrogeological conditions. The key data used to compare these different regions are climate and soils, available water resources and their use, as well as components of the water balance. In addition, the history of water resource development in these areas is examined to understand how salinity problems emerge in semi-arid regions and the consequences for production. Based on the efficiency parameters and the definitions of sustainability, approaches are explored to solve common environmental problems while maintaining economic viability and environmental sustainability for irrigation systems.     

Modelling worker physical health and societal sustainability at farm level: An application to conventional and organic dairy farming

Farm-level modelling can be used to determine how farming systems and individual farm-management measures influence different sustainability indicators. Until now however, worker physical health and societal sustainability have been lacking in farm models. For this paper, we first selected attributes of physical health (working conditions) and societal sustainability (food safety, animal welfare and health, and landscape quality). Second, possible sustainability indicators for these attributes were identified, and those selected were included in an existing dairy farm LP-model that was subsequently used to analyse possible differences in societal sustainability within and between a conventional and organic dairy farming system. Results for physical health and societal sustainability were similar for conventional and organic dairy farming systems in the basis situation, as well as in the situation where additional management measures were applied to improve societal sustainability, but improved animal welfare did result in the organic system due to prescribed grazing, and due to assumed summer feeding in the conventional system. Results show that additional management measures considerably improved societal sustainability of the conventional as well as the organic system. LP-modelling appeared to be a suitable method for comparing farming systems and determining the effect of management measures on physical health and societal sustainability. The level of societal sustainability is determined mainly by applied management measures, and is related to the particular farming system in only a very limited way. This implies that societal sustainability is mainly dependent on the cost-effectiveness of management measures and on the attitude of the dairy farmer.     

新疆节水农业区划及分区对策研究

新疆全区地貌与气候差异性大,造成农业结构及发展在区域上也存在较大差异,因此有必要对节水农业进行分区规划以指导新疆节水农业的发展.运用主成分分析和模糊ISODATA聚类分析相结合的数学方法,以县为单位,对新疆86个县(市)进行了节水农业区划,将其划分为10个节水农业类型区,并针对各分区提出了相应的节水农业发展模式.     

An integrated sustainability assessment of mediterranean sheep farms with different degrees of intensification

In the European Mediterranean basin, pasture-based sheep farming systems are mostly located in marginal/High Nature Value areas. These production systems are multifunctional, and their economic, environmental and social roles are equally important and recognised by policy makers and by society. However, the number of animals and holdings is decreasing, and there is great uncertainty regarding the reproducibility of these farming systems, which depends on many internal and external farm factors and their interactions. The aim of this paper was to perform a comprehensive assessment of sustainability in different sheep farming systems in north eastern Spain using the MESMIS framework. We followed a case-study approach to perform an in-depth investigation of 4 sheep meat and dairy farms with different intensities of reproduction management. Critical points of sustainability, including weaknesses and opportunities, were obtained using a participatory process with stakeholders (farmers and technical advisers) that resulted in the selection of 37 sustainability indicators that were classified according to the systemic attributes defined by MESMIS (productivity, stability, self-reliance, adaptability, equity) and according to the classical sustainability pillars (social, economic and environmental). Some underlying patterns could be observed when analysing sustainability pillars, attributes and indicators. A positive relationship between productivity and intensification level in meat farms was observed; however, economic sustainability was determined not only by on-farm but also by off-farm activities. The economic efficiency of farming (without considering subsidies) was mainly explained by the capture of added value in the dairy systems and the combination of high animal productivity as well as high forage and feed self-sufficiency in the meat systems. Social issues were also central to explaining sustainability at the farm level, including the prospects of generational turnover and the manner in which farmers perceive and rate their activity. A clear trade-off between economic and environmental indicators was observed, i.e., the higher the economic sustainability, the lower the environmental sustainability. Each farm scored differently for diverse attributes, pillars and individual indicators. The scores differed according to size, structure, resource availability and managerial skills, which implies that it would be difficult to apply a holistic sustainability analysis to farming systems instead of individual farms. A number of methodological questions arose during the evaluation process relative to the stakeholders perception of these indicators, their relevance and meaning, the reference values for comparison, or their validity to assess sustainability across spatial and temporal scales. These questions are discussed in the paper.     

Distribution of soil water-stable aggrega-tes and organic carbon content affectedby tillage systems: a meta analysis

A better understanding of soil carbon( C) distribution within aggregate fractions is essential to evaluating the potential of no-till for sustaining productivity and protecting the environment. A metaanalysis on 744 comparisons from 34 studies was conducted to determine the effects of three different tillage treatments( conventional mouldbould ploughing tillage( CT),reduced tillage( RT) and no tillage( NT)) on water-stable aggregate size distribution,soil C concentration in aggregate fractions.The meta-analysis indicates that compared with CT treatment, NT/RT significantly( P 0. 05)increases macro-aggregate above 20 cm by 20. 9%-82. 2%( 2. 00 mm) and 5. 9%-19. 1%( 0. 25-2.00 mm),whereas NT/RT significantly reduces micro-aggregate and silt clay fractions above 20 cm.NT/RT significantly( P 0. 05) increases the SOC in macro-aggregate( 0. 25 mm) and microaggregate( 0. 25 mm) size classes above 20 cm soil depth compared with CT. The results suggest that soil sampling depth should be considered to evaluate the influence of tillage systems on the distribution of soil aggregate,and the content of aggregate-associated C content.     

湖南省农业机械化技术推广可持续性探讨

湖南是中国的农业大省,文章尝试对湖南农业机械化技术推广的现状进行分析,以期建立起适合湖南基层农业的农业机械化技术推广模式。文章认为,实现湖南农业机械化技术推广的可持续性,应优化农业机械化技术推广的政策环境、加大扶持力度和经费投入、完善管理体制和运行机制、构建可持续发展的农机技术推广人才培养模式、开发新型农机化装备、调整农机产业区域布局、发展生态农业。