Soil degradation and agricultural sustainability: an overview from Iran

During the past six decades, agriculture as a main sector in Iran’s economy has been affected by economic development, land-use policies, and population growth and its pressures. From the 1940s until 2010, the percentage of the total urban population of Iran increased from about 21?% to around 72?%. Urbanization, industrialization, and intensive cultivation have dramatically affected soil and water resources. The exploitation of groundwater has been increased around fourfold from the 1970s to the mid-2000s. Total water resources per capita reduced around 23?% from 1956 to 2008. The average annual decrease in the groundwater table in Iran during the last two decades is 0.51?m. In 2008, the groundwater table fell around ?1.14?m in average in Iran. The average use of chemical fertilizers increased from around 2.1?million tons in 1990s to about 3.7?million tons in 2009. During that period, fertilizer use efficiency decreased from around 28?% to around 21?%. Approximately 77?% of the agricultural land under irrigation suffers from different levels of salinity. According to the quantification of four indices, such as soil erosion, fall in groundwater levels, salinity, and use of chemical fertilizer, that are directly related to agricultural land use, the results show that agricultural management in Iran needs special attention to reach sustainable conditions. The total cost of soil and water degradation and use of fertilizers in agriculture are estimated around than US $12.8?billion (about 157,000?billion IRRials)—approximately 4?% of the total gross domestic product (GDP) and approximately 35?% of the GDP of the agricultural sector in Iran.     

Developing a sustainability assessment framework for integrated management of water resources systems using distributed zoning and system dynamics approaches

The management of large-scale water resources systems requires including of different stakeholders and users from municipal, agricultural, industrial and environmental sectors. This has baffled the process of decision making for integrated water resource systems. In such systems, the interactions between various stakeholders must be carefully taken into account with the goal of aggregating interests around the sustainability concept. In this study, first, the integrated water resources systems of Big Karun Watershed, Iran, have been modeled using the system dynamics approach. The system dynamics model represents the interactions between different components of the system, including water transfer projects, dams, urban, industry, agriculture and fish farming, and environmental demands. Vensim software has been used for the system dynamics modeling. Vensim simulates the dynamics behavior of the sub-systems and overall performance of the system by comparing the current operation policies with the future management scenarios. A wide range of performance indices, such as quantitative and qualitative water stress, income, cost, and productivity, have been used here to represent different aspects of sustainability goals. Finally, the performance of the systems has been evaluated by developing a sustainability index using distributed zoning model in order to identify proper management policies for this watershed. The results indicate that downstream users demand cannot be fully met by solely considering inter-basin water transfer and agricultural development projects. The sustainable and integrated management of the whole system ties into enhancement in both infrastructure systems and the operation of the whole system. It is expected that the sustainability of the basin improves if a water market schema exists and the gained money would be used to enhance the efficiency of existing irrigation networks.

     

A quantitative water resource planning and management model for an industrial park level

This paper introduces an integrated water management model at the industrial park level. It suggests four approaches to water management: first, direct water reuse among users; second, water reuse among users by blending with freshwater; third, water reuse between users and a wastewater treatment plant; and fourth, groundwater recharge by reclaimed wastewater or other feasible applications in order to optimize the overall water efficiency. The model results in a comprehensive management methodology for optimizing water resources within an industrial park, seeking potential water reuse among industries, and incorporating the size and cost of reclaimed wastewater delivery systems. A case study is employed to test the model’s feasibility. An economic analysis of the optimized water use network is also carried out, showing the potential water and cost savings.     

Factors affecting incentive dependency of residents to participate in e-waste recycling: a case study on adoption of e-waste reverse supply chain in Iran

Modern societies face a dilemma called electronic waste (e-waste). This waste, which may contaminate the soil or cause unwanted impacts on human health when treated improperly, is one of the fastest growing waste streams in developed as well as developing countries and has brought great environmental impacts. Developing countries like Iran also face this modern waste management challenge. In order for more appropriate disposal or, if possible, recycling of this waste, more attention has been paid to reverse logistics as the most appropriate way to manage them. The first and most important action to address e-waste and implementation of reverse logistics is to persuade residents to bring back their obsolete electronic products. This paper attempts to understand significant factors affecting residents’ incentive dependency to participate in e-waste recycling program. Socioeconomic and demographic information of different residents is discussed by means of logistic regression for the first time in Iran. The results show that about 58.7 % of residents will participate even if no incentive is given. Household income, household size, education, e-waste concern level, and marital status are the significant factors affecting the incentive dependency of respondents.     

Sustaining water supply through a phased community management approach: lessons from Ghana’s “oats” water supply scheme

Water sector reforms in Ghana and in other developing countries resulted in the adoption of the community management approach for water systems in an effort to ensure better management and service delivery. However, community management is also plagued internal differences, paucity of technical skills, and insufficient management experience. This article presents a case study of a successful community management system in Ghana that utilized a two-phase comanagement period before a full transfer of management responsibilities to the four communities. The first phase of 3 months was a more intensive comanagement system under which the communities teamed up with public agencies and a private firm to manage the water system. This enabled the communities to acquire hands-on management experience and also tap needed skills from external agencies before a second phase of 3 months characterized by gradual withdrawal of private agency support, and a simultaneous measured assumption of higher responsibilities by the communities. Communities thereafter assumed full management responsibility of the water system and have since then posted significant successes in financial management and operations of the system such that some profits have been generated, there is regular water supply and the system operates without major technical hitches. This strategy illustrates the fact that successful community management system is possible if local capacity is adequately strengthened with external support prior to assumption of full community control of water supply systems, and if assumption of responsibilities is pursued gradually.     

长江流域节水前景与措施浅析

长江流域涉及19个省、市、自治区，面积180万km^2，人均水资源量2288m^3，略高于全国平均水平，属水资源相对丰富地区。但水资源时空分布不均衡、水污染日趋严重、浪费水现象十分突出等问题．导致流域内资源型缺水、水质型缺水和工程管理型缺水均存在。通过对长江流域节水必要性的论述，对流域内落后的农业灌溉方式和用水管理模式以及落后的生活和工业供用水设施等导致的水利用效率低下现状与先进水平的比较，分析了流域内节水的广阔前景，同时针对目前认识观念和投入不足、机制不力、法制不强等节水工作软环境存在的问题，提出了节流优先、治污为本、多渠道开源、加强水管理和提高水效率、政府引导和市场推动相结合的重点解决措施。     

Discovering and characterizing farm households’ resilience under water scarcity

Water scarcity at an alarming rate has been a limiting factor for sustainable agriculture in arid and semi-arid environments of the world. It has resulted in a number of problems such as poverty and food insecurity among farm households. Therefore, building and improving resilience, as a way to mitigate the impacts of water scarcity, is important for farm households. But one of the significant steps for planning to improve farm households’ resilience under water scarcity is investigation of the current level of resilience of these households and understanding their variances. Therefore, this study offers a classification of farm households’ diversity based on resilience. Primary data were collected from 260 randomly selected farm households in 21 villages around Parishan wetland, Iran. Farm Household Resilience Scale was used to measure resilience. Cluster analysis suggested three groups: highly, medium-, and low-resilient farm households. The results of comparing three groups revealed that highly resilient farm households characterize with higher risk management, more agricultural water security, more positive psychological traits, and better knowledge management. Also, they had better water quality, attended more agricultural extension activities, and used modern irrigation systems. Farm households’ resilience map using GIS software illustrated that there is a relationship between resilience and farm location from the wetland. The findings of this study could be used by planner and policy-makers to improve farm households’ resilience in arid and semi-arid environments. Improvement in knowledge management system is recommended as one of the most effective policy instruments in building resilience.     

Rethinking assessment of drought impacts: a systemic approach towards sustainability

Although impacting primarily economic sectors, droughts may also initiate dynamic mechanisms that have socio-environmental consequences on sustainability of the impacted areas. To date, most research has dealt with the economic impacts of droughts, with minimal attention being paid to the dynamics of damaging mechanisms associated with socio-environmental impacts. Using a systemic approach, this paper develops a method of identifying the dynamic structures responsible for the consequences of drought. Considering the impacts of recent droughts in Iran, the paper presents a conceptual model, underpinned by a Limits to Growth archetype to explain how different drought impacts are triggered. Moreover, adopting the Viability Loops concept, a range of strategies and indices are suggested as monitoring tools to sustain socio-economic life in a drought-impacted area. The provinces of Hamadan (with water abundance), and Yazd and Isfahan (with water scarcity) in Iran have been selected to illustrate the proposed methodology. Results show a higher vulnerability to droughts in the water-rich region due to dependence on water abundance as opposed to the water-poor regions, which are well adapted to water scarcity conditions.     

环境约束下中国省际水资源两阶段效率及影响因素研究

本文把水资源利用系统分为水资源利用阶段和污染物处理阶段,在环境规制下采用考虑非期望产出的两阶段SBM模型,对2001—2014年中国31个省级行政区的水资源利用整体效率和各阶段效率进行测度,并利用空间自相关分析方法对中国各地区水资源利用整体效率的时空特征进行分析,然后运用考虑空间效应因素的空间滞后计量模型和空间误差计量模型从人均水资源量、工业用水量、生活用水量、人均GDP、对外开放程度、产业结构、技术进步等方面对各地区水资源利用整体效率的影响因素进行分析。结果表明:(1)整体上看水资源利用第一阶段效率明显高于第二阶段效率,而整体效率接近于第二阶段效率,第二阶段效率决定了水资源利用整体有效性。(2)通过各阶段投入产出冗余来看,水资源污染物产出过多和处理不足是导致第二阶段效率不高的原因。(3)水资源利用整体效率的空间自相关强度显著大于0,在空间上呈现集聚分布特征,东部沿海地区为H-H集聚类型,中部和西部为L-L集聚类型。(4)各地区水资源利用整体效率存在空间溢出效应,一个地区的整体效率不仅受本地区因素影响,还受临近地区整体效率的影响。(5)在考虑和不考虑空间效应的计量估计结果中,工业用水量对整体效率产生显著的负向影响,而人均GDP、对外开放程度对整体效率产生显著的正向影响。根据实证结果,得出以下结论:一是加强水资源污染物排放管理,增强污水处理能力;二是实现高效工业用水,减少工业用水量;三是发挥各地区水资源禀赋优势,加强区域合作,优化水资源区域配置,促进经济-环境协调可持续发展。     

Indoor radon monitoring in Northern Iran using passive and active measurements

In this work we present the results of a 2-year survey of indoor radon variations in four cities of Lahijan, Ardabil, Sar-Ein and Namin in North and Northwest Iran. We used both passive and active measurements by solid state nuclear track detectors (SSNTDs) with CR-39 polycarbonate and PRASSI Portable radon Gas Surveyor. A total of 1124 samplers in Lahijan, Ardabil, Sar-Ein and Namin were installed. Sampling frequency was seasonal and sampling locations were randomly chosen based on dwelling structures, floors, geological formations, elevation and temperature variation parameters. For quality assurance, 281 active measurements and double sampling were carried out. Based on our results and the results of previous surveys, Ardabil and Lahijan have the second and third highest radon concentration in Iran, respectively (Ramsar is first). The average radon concentration during the year in Lahijan, Ardabil, Sar-Ein and Namin were 163, 240, 160 and 144 Bq/m(3) with medians of 160, 168, 124 and 133 Bq/m(3), respectively. These concentrations give rise to annual effective doses of 3.43 mSv/y for Lahijan and 5.00 mSv/y for Ardabil. The maximum recorded concentration was 2386 Bq/m(3) during winter in Ardabil and the minimum concentration was 55 Bq/m(3) during spring in Lahijan. Relationships between radon concentration and building materials and room ventilation were also studied. The dosimetry calculations showed that these four cities could be categorized as average natural radiation zones. The correlation coefficients relating warm and cold season radon variation data were obtained.     

基于最严格水资源管理制度的初始水权分配研究

实行最严格水资源管理制度是2011年中央一号文件明确要求的内容。在分析最严格水资源管理初始水权分配内涵的基础上,首次以水资源管理“三条红线”为准则,构建了包含目标层、准则层、指标层及方案层4个层次结构的初始水权分配指标体系,建立了最严格水资源管理初始水权分配的投影寻踪模型,并采用量子遗传算法优化投影指标函数,以模型计算出的最佳投影值作为初始水权分配的分水比例。最后,以南水北调东线一期工程为例,将本文所建立的模型用来分配该工程净增加供水量的初始调水量。结果表明:该指标体系和模型具有一定的可操作性及有效性。     

多瑙河国际水争端仲裁案对我国国际河流开发的启示

多瑙河水争端仲裁案是国际法庭首例仲裁解决的生态环境案例。在对该案的产生、发展及仲裁结论的分析与总结基础上,结合当今淡水资源日趋紧张,国际河流水资源的合理利用与管理已成为国际社会广泛关注的重要问题的现状,认为该案将对我国未来国际河流水资源的开发利用带来启示：加强对我国境内国际河流水资源的“国际”法制化管理;协调国家与地方、国家间的水资源利用目标,促进国际河流水资源的公平合理利用与保护;认识与了解我国国际河流水资源开发利用中的国际责任与义务;认识国际河流水资源的有限利用权与使用权;国际河流水资源公平合理利用权利受限于流域国家的合作基础;参与制定并实施国际河流区域性开发协定是实现国际河流管理与保护的重要条件等。     

丹江口水源区水生态功能一二级分区研究

水生态功能分区是实现流域水环境"分区、分级、分类、分期"管理的基础。以高程、干燥度及年均径流深为一级分区指标,土地利用、土壤类型、坡度、人均GDP为二级分区指标,将丹江口水源区分为6个一级水生态功能区和19个二级水生态功能区。比较不同分区的水生境状况及底栖动物种群结构特征,发现一级分区间的水生境状况与底栖动物种群结构均存在差异,二级分区之间虽然有部分生境指标较为接近,但底栖动物种群结构差异明显,证明了分区方案的科学性和合理性,为水源区的生态系统保护和水资源管理提供了依据。     

Parametric uncertainty analysis on hydrodynamic coefficients in groundwater numerical models using Monte Carlo method and RPEM

Groundwater resources are the only source of water in many arid and semi-arid regions. It is important to manage these resources to have a sustainable development. However, there are many factors influencing the accuracy of the results in groundwater modeling. In this research, the uncertainty of two important groundwater model parameters (hydraulic conductivity and specific yield) were considered as the main sources of uncertainty in estimating water level in an unconfined aquifer, in Iran. For this purpose, a simple method called Rosenblueth Point Estimate Method (RPEM) was used to assess groundwater modeling parametric uncertainty, and its performance was compared with Monte Carlo method as a very complicated and time-consuming method. According to calibrated values of hydraulic conductivity and specific yield, several uncertainty intervals were considered to analyze uncertainty. The results showed that the optimum interval for hydraulic conductivity was 40% increase–30% decrease of the calibrated values in both Monte Carlo and RPEM methods. This interval for specific yield was 200% increase–90% decrease of the calibrated values. RPEM showed better performance using the evaluating indices in comparison with Monte Carlo method for both hydraulic conductivity and specific yield with 43% and 17% higher index values, respectively. These results can be used in groundwater management and future prediction of groundwater level.

     

Response curves of seventeen woody species to soil factors along a riparian forest in northern Iran

The aim of this study was to determine type of response curves for seventeen woody species (10 tree and 7 shrub species) to soil factors in an intact riparian forest in Safaroud River in northern Iran using HOF function. Data were collected along transects established perpendicular to the water flow on both sides of the river. Results indicated different responses for different woody species. The most common were symmetricunimodal response curves and curves showing an increase in occurrence probability after a certain value in form of a plateau. Bimodal curves were four times more frequent in riverside than forest interior area. It seems that river flow disturbances through frequent floods effect on species tolerance and optimum in riversides.     

我国流域水资源管理模式理论创新初探

在以水资源过度开发、水环境污染、水资源短缺及用水效率和效益低下为主要标志的水危机日益凸显的今天,探寻和构建与中国国情相适应、并能反映先进生态水文化的现代水资源管理模式,是解决我国流域目前面临的水问题、应对未来不断加剧的水危机、实现区域经济与社会可持续发展的必由之路和战略抉择.在对国内外水资源管理模式的发展动态及研究进展系统评述的基础上,本文提出从传统的以行政区域为单元、以政府为主导、以供水管理为核心的水资源管理模式向以流域为单元、以市场为主导、以需水管理为基础的水资源综合管理模式的转变,是未来我国流域水资源管理模式理论创新的重要发展方向,并从流域水资源的管理制度、文化体系、管理模式、法律及政策体系方面进行详细论述.     

基于DEMATEL的区域洪涝灾害恢复力影响因素及评价指标体系研究——以巢湖流域为例

影响洪涝灾害恢复力的因素众多且相互关联,识别和区分这些影响因素,找到因素间互相影响程度和因果关系,对于明确洪涝灾害恢复力关键因素,快速找到需要改善的因素具有重要意义。通过分析灾害恢复力的内涵,从自然维、社会维、经济维、技术维、管理维5个维度构建区域洪涝灾害恢复力的影响因素指标体系,应用DEMATEL方法分析区域洪涝灾害恢复力影响因素之间的关系,并以巢湖流域为例凝练出适合该区域的洪涝灾害恢复力评价指标体系,结果表明,一级指标中自然维、经济维对其他因素影响最为显著,二级指标中政府财政支撑能力、土地因子、地形因子对其他影响因素的影响最大;而一级指标中经济维和社会维与其他因素关系最为密切,二级指标中政府财政支撑能力、区域经济实力、土地因子处于核心的位置。从整体影响输出上看,一级指标中原因因素共有2个,分别为自然维、经济维,且以经济维为最,二级指标中原因因素有11个,涉及五个维度,包括所有自然维中因素,并以地形因子、政府财政支撑能力、灾害政策法规为重。一级指标中结果因素有3个,分别为管理维、技术维、社会维;二级指标中共有12个,以管理维中的因素为主,相比于原因因素,通过改善结果因素可以更直接的提高区域洪涝灾害恢复力的水平。     

湖泊型水源地管理研究——以苏州市太湖水源地为例

饮用水安全是最大的民生工程,也是自然资源管理研究的热点。基于实地调研、部门访谈和制度条文的梳理与分析,以苏州市太湖水源地为例研究湖泊型水源地管理体制。研究表明：我国水源地管理由国家、省、市、县的法律法规、规章和规范性文件构成相对完善的制度体系,具有水资源和水环境分割管理、流域管理和行政区管理交错的制度特征,初步具备了综合管理的架构;水源保护缺乏流域管治的思维,农村面源污染治理制度支撑不足;在管理手段上以命令控制型手段为主,经济激励与公众参与不足。建立水源地综合管理协调机制,完善经济激励手段,推进公众参与,实施水源地管理共同责任机制将有利于提高水源地管理效率     

A multiple criteria evaluation of sustainable agricultural development models using AHP

Selection of the appropriate agricultural development model has become an important issue in Iran. Using data from Fars province of Iran, the purpose of this paper is to use analytic hierarchy process (AHP) for selecting between the two competing sustainable agricultural development models, which have been developed based on the general tenets of Ecological Modernization (EM) and De-Modernization (DM) theories. Farmers, environmentalists, board members of rural cooperative, rural women and experts from Fars Agricultural (Jehad-e-Keshavarzi) Organization participated in application of AHP to this study. They applied AHP to determine the priority of DM and EM based sustainable agricultural development models. Each group determined the priority of the two models for sustainable agricultural development. The findings indicated that ecological criteria i.e. wise use of resources, environmental protection and product quality are the most important criteria for sustainable agriculture of Iran, followed by economic criterion employment and social criterion participation. A sensitivity analysis was carried out to determine the critical factors that affected the priority of alternatives. The results indicated that EM-based sustainable agricultural development model has a higher priority as the theoretical base of agricultural development of Iran. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue     

元谋干热河谷民营水土保持发展的驱动力研究

民营水土保持是当今水土保持生态建设中出现的一种新模式。以元谋干热河谷区为研究范围，通过对农户调查资料的分析，确定民营水土保持发展的驱动力因子为农户经济发展水平、农户兼业经济行为、农户家庭劳动力状况、农户经营规模、政府行为5大类，并对5大指标进行细化、量化，运用相关分析、因子分析等定量统计分析方法对元谋干热河谷区的民营水土保持发展的驱动力因子进行定量分析，结果表明，经济因子是影响民营水土保持发展的第一因子。