干旱区绿洲农业生态系统特征及持续发展关键问题

干旱区绿洲农业生态系统特征及持续发展关键问题袁国映（新疆环境保护科学研究所乌鲁木齐８３００１１）干旱区绿洲大农业生态系统是在原有的自然绿洲荒漠戈壁上，经过人类开垦和长期的灌溉耕作形成的。绿洲农业在我国已有二、三千年以上的历史，随着历史上经济的发展，已...     

新疆南部河水中微量元素的初步探索

水在新疆是十分宝贵的,在南疆更是如此。新疆南部有径流统计的河流约有九十五条,年径流量387.59亿方,占全疆的49.9％。如何合理地开发利用这些水资源,从古到今,都是南疆各族人民十分关切的问题。在河流等天然水中溶解的化学物质,对工业生产、农业灌溉、生活用水及渔业养殖     

新疆山地垂直自然带的地区差异及经济意义

新疆地貌大体由“三山两盆”组成。由北到南纬度约相差5—6℃的阿尔泰山、天山、昆仑山及阿尔金山,其山地垂直自然景观带也有着规律的变化;自然带谱由北向南和由西到东逐渐单调,且表现出越加干旱,森林带树木种类减少,雪线上升约差1000m;各自然带的高度也随纬度减低而升高。三大山系均为新疆灌溉农业的支柱,是畜牧业的靠山,是野生动植物的摇蓝,也是矿业的集中区。阿尔泰山和天山还是新疆优质木材的主要基地。因此,山地垂直自然带在新疆经济发展中起着决定作用。     

土地处理系统在新疆城镇废水治理中应用的探讨

一、概述新疆是我国典型的干旱和半干旱地区,年蒸发量远远大于降水量,因而使全区百分之九十五的农业依靠灌溉。由于水资源的缺乏限制了农牧业生产的发展。而城镇废水这一比较稳定的水、肥资源在我区或者没有充分利用,或者因不合理的污灌方法而造成程度不同的环境污染。因此发展土地处理系统合理利用城镇污水,使污水回用以增加部分水、肥资源是我     

痕量灌溉水分运移调控与水分分布过程实验研究

新疆属典型干旱区,水资源严重缺乏,这决定了在新疆任何生产与生活活动都与水资源息息相关。如何在保持经济发展的前提下提高水资源利用效率,同时兼顾生态用水成为当下研究热点。本文以新兴节水灌溉技术痕量灌溉技术为研究对象,通过试验,研究痕量灌溉技术在新疆不同土质与不同工程参数下的水分运移分布规律。同时结合保水剂的使用,研究痕量灌溉技术在与保水剂联合使用条件下的水分运移规律。结果表明:1土壤土质主要影响湿润体的大小及形状,土质由粘土向沙土过渡,湿润体表现出水平长度减少而垂直向下长度增加的趋势,不同土质中的含水率由土壤物理结构与测点距灌水中心距离决定;2埋深因素主要影响湿润体垂直长度,对含水率变化影响不明显;3保水剂不同施用方式对湿润体的影响不同。     

新疆水资源开发利用与生态问题

新疆作为干旱区的典型省区,其气候条件、水分等自然因素决定了该省区是以内陆河流域为特征的生态系统。本文论述了该省区的自然生态条件及发展绿洲灌溉农业的生态变化,并陈述了生态变化导致的土地荒漠化为特征的生态问题。     

关于世行贷款农业灌溉项目环境影响评价问题的讨论

农业灌溉工程建设是我国第十二个五年规划纲要中提出的全面加强农田水利建设工作的重要组成部分。随着越来越多农业灌溉项目的兴建及我国环境影响评价制度的发展,农业灌溉项目的环境影响评价也在不断发展和完善中。本文根据世行贷款项目——中国四川武都农业灌溉项目环境影响评价实践和工作经验,分析总结了世界银行及我国在农业灌溉项目环境影响评价工作方面的特点和要求,其中世界银行在有些方面,如评价等级、公众参与等与国内环评要求基本一致,而有些方面,如回顾性评价、替代方案分析、累积性影响分析、环境管理计划、移民安置行动计划、病虫害管理计划等在国内环境影响评价中尚未引起足够的关注或与世界银行要求存在较大差异,值得我国环评工作参考和借鉴。     

引草入田,发展新疆的草地农业

引草入田，发展新疆的草地农业王博，于振田，安瑞麟（新疆畜牧科学院草原研究所乌鲁木齐８３００００）我国农业面临着进入以调整结构、提高效益为主要特征的新阶段“’，而技术进步则是迈上新台阶最重要的手段。引草入田，发展新疆的草地农业应是推进农业产业技术进步的...     

新疆农业生态环境面临的问题与保护措施

新疆农业生态环境面临的主要问题有两大类:一类问题为生态问题;另一类问题为环境污染问题。简要介绍了新疆农业生态环境面临的生态问题,重点介绍了新疆农业生态环境面临的环境污染问题。针对新疆农业生态环境存在的问题,提出了相应的保护措施。     

试论新疆土地退化对生态环境和国民经济发展的影响

新疆土地退化严重,对生态环境的危害日益加深,其中草地退化导致畜牧业长期不能很快发展,林地萎缩严重危及绿洲灌溉农业,耕地衰退造成粮食单产长期不能很快提高.遏制并逆转土地退化是当前发展农业生产的重大课题,其主要措施是:1.以治水改土为中心,搞好流域规划,建立绿洲生态系统的良性循环,2.以植树种草为基础,建立绿洲林网结构,逆转耕地沙化,3.以农田基本建设为前提,综合治理盐碱地,改造低产田.     

提高农业用水效率促进农业可持续性发展

乐亭县地处滨海,农业用水效率低,加之上游连年缺水,造成田间荒芜撂荒现象严重.乐亭县是农业大县,工业相对薄弱,掀起一场提高农业用水效率的革命势在必行.主要途径:大力推进节水灌溉制度,调整农业种植结构,积极引进、开发、培育节水高产品种,减少无效蒸发,节水高产施肥、培肥技术.     

新疆水土流失及防治对策

新疆生态环境脆弱，水土流失严重，治理任务艰巨，近年来，随着新疆大开发建设，水土流失有加剧的态势，为保护人们居住的生存环境，治理水土流失已显得刻不容缓，为防治我区水土流失，首先应根据新疆水土流失的特点和目前水土保持工作中存在的主要问题，研究和提出水土流失防治的对策。     

Surface Water Seepage Effects on Shallow Ground‐Water Quality Along the Rio Grande in Northern New Mexico1

Abstract: Interactions between surface irrigation water, shallow ground water, and river water may have effects on water quality that are important for both drinking water supplies and the ecological function of rivers and floodplains. We investigated water quality in surface water and ground water, and how water quality is influenced by surface water inputs from an unlined irrigation system in the Alcalde Valley of the Rio Grande in northern New Mexico. From August 2005 to July 2006, we sampled ground water and surface water monthly and analyzed for concentrations of major cations and anions, specific conductance, pH, dissolved oxygen, and water levels. Results indicate that irrigation ditch seepage caused an increase in ground water levels and that the Rio Grande is a gaining stream in this region. Temporal and spatial differences were found in ion concentrations in shallow ground water as it flowed from under the ditch toward the river. Ground‐water ion concentrations were higher when the ditch was not flowing compared with periods during peak irrigation season when the ditch was flowing. Ditch inputs diluted ion concentrations in shallow ground water at well positions near the ditch. Specifically, lower ion concentrations were detected in ground water at well positions located near the ditch and river compared with well positions located in the middle of an agricultural field. Results from this project showed that ditch inputs influenced ion concentrations and were associated with ground‐water recharge. In arid region river valleys, careful consideration should be given to management scenarios that change seepage from irrigation systems, because in some situations reduced seepage could negatively affect ground‐water recharge and water quality.     

Water quality management for sustainable agricultural development

This paper presents an analysis of water quality management in the context of increased and sustainable agricultural production through irrigation. Irrigation practices for optimum yield and sustainability are examined as are the environmental and health aspects of irrigation farming.     

A Framework for Incorporating the Impact of Water Quality on Water Supply Stress: An Example from Louisiana,USA

Water of poor quality can directly impact the budget of water available for key user groups. Despite this importance, methods for quantifying the impact of water quality on water availability remain elusive. Here, we develop a new framework for incorporating the impact of water quality on water supply by modifying the Water Supply Stress Index (WaSSI). We demonstrate the usefulness of the framework by investigating the impact of high salinity waters on the availability of irrigation water for agriculture in Louisiana. The WaSSI was deconstructed into sectoral components such that the total available water supply could be reduced for a particular demand sector (agricultural irrigation in this example) based on available water quality information. The results for Louisiana highlight substantial impacts on water supply stress for farmers attributable to the landward encroachment of saline surface water and groundwater near the coast. Areas of high salinity near the coast also increased the competition for freshwater resources among the industrial, municipal, and agricultural demand sectors in the vicinities of the municipal areas of Lake Charles, Lafayette, and Baton Rouge, Louisiana. The framework developed here is easily adaptable for other water quality concerns and for other demand sectors, and as such can serve as a useful tool for water managers.     

农业水资源价值计算方法研究

农业水资源价值的计算对灌区农业用水价格的制定具有重要的意义,同时也可用于对农业用水向其它类型用水转移时所受的经济损失进行估算。因此,当前将农业用水当作商品并计算其价值逐渐成为热点,尤其是在发展中国家的大型灌区和干旱、半干旱地区。对农业水资源价值的计算方法进行了综述,总结了农业水资源价值计算的两种方法,并列举了具体的计算模型和公式,提出了农业水资源价值计算中应考虑的问题,为进一步研究农业水资源价值提供参考。     

Emergy Assessment of a Wheat-Maize Rotation System with Different Water Assignments in the North China Plain

Sustainable water use is seriously compromised in the North China Plain (NCP) due to the huge water requirements of agriculture, the largest use of water resources. An integrated approach which combines the ecosystem model with emergy analysis is presented to determine the optimum quantity of irrigation for sustainable development in irrigated cropping systems. Since the traditional emergy method pays little attention to the dynamic interaction among components of the ecological system and dynamic emergy accounting is in its infancy, it is hard to evaluate the cropping system in hypothetical situations or in response to specific changes. In order to solve this problem, an ecosystem model (Vegetation Interface Processes (VIP) model) is introduced for emergy analysis to describe the production processes. Some raw data, collected by investigating or observing in conventional emergy analysis, may be calculated by the VIP model in the new approach. To demonstrate the advantage of this new approach, we use it to assess the wheat-maize rotation cropping system at different irrigation levels and derive the optimum quantity of irrigation according to the index of ecosystem sustainable development in NCP. The results show, the optimum quantity of irrigation in this region should be 240–330 mm per year in the wheat system and no irrigation in the maize system, because with this quantity of irrigation the rotation crop system reveals: best efficiency in energy transformation (transformity = 6.05E + 4 sej/J); highest sustainability (renewability = 25%); lowest environmental impact (environmental loading ratio = 3.5) and the greatest sustainability index (Emergy Sustainability Index = 0.47) compared with the system in other irrigation amounts. This study demonstrates that application of the new approach is broader than the conventional emergy analysis and the new approach is helpful in optimizing resources allocation, resource-savings and maintaining agricultural sustainability.     

Planning Agricultural Water Resources System Associated With Fuzzy and Random Features1

Li, Y.P. and G.H. Huang, 2011. Planning Agricultural Water Resources System Associated With Fuzzy and Random Features. Journal of the American Water Resources Association (JAWRA) 47(4):841‐860. DOI: 10.1111/j.1752‐1688.2011.00558.x Abstract: More and more regions where demand outstrips water resources availability have suffered from chronic severe shortages. It is particularly aggravated for agricultural irrigation systems where more water is necessary to support the rapidly increasing population and speedily developing economy. In this study, a two‐stage fuzzy‐stochastic programming (TFSP) method is developed for planning agricultural water resources management system in more efficient and sustainable ways. The developed method can address uncertain parameters described as probability distributions and fuzzy sets. It can also be used for analyzing various policy scenarios that are associated with different levels of economic consequences since penalties are exercised with recourse actions against any infeasibility. The developed method is applied to agricultural water‐resources management planning of the Zhangweinan River Basin, China. Solutions under various α‐cut levels and fuzzy dominance indices can be generated by solving a series of deterministic submodels, which can help determine optimized crop‐target values that could hedge appropriately against future available water levels. The results are helpful for water resources managers in not only making decisions of crop irrigation but also gaining insight into the tradeoffs between economic objective and system‐failure risk.     

Water stress, water transfer and social equity in Northern China--implications for policy reforms

Water stress in Northern China is characterized with major, inefficient irrigation water use and rapidly growing non-agricultural water demands, as well as limited water quantity and declining water quality. Water use in the region is undergoing transfer from agricultural to municipal and industrial sectors. Currently, part of the economic loss and environmental damage due to water stress can be considered as a consequence of water transfer failures, including the current transfers, which hurt farmers' livelihood and income, and the needed transfers, which industry and cities have been waiting for but have not received. This paper starts with a discussion of the causes of water stress in Northern China, which is fundamental to understand the necessity and complexity of agricultural water transfers. Following that, it reviews water transfers in Northern China as a cause for concern over the social stability, economy and environment of the region. Based on an integrated analysis of economic, environmental, fiscal and social implications, this paper begins by identifying critical barriers to smooth water redistribution; and ends with implications for policy reforms, ensuring that farmers can and will save water. It is concluded that the decisions of water reallocation under water stress should be shared by communities at all levels, from the local to the national, to ensure equal access of water, especially the availability of the basic water need for all groups.     

OPTIMIZATION OF WATER RESOURCES FOR IRRIGATION IN EAST JORDAN1

The paper describes an approach towards optimal allocation of surface and ground water resources to three agricultural areas in the Jordan Valley under conditions of scarce water supply. The optimizing model allocates water from three main rivers, each with reservoir storage, and from two ground water sources to three irrigation regions. Productivity of irrigation water, expressed as the net present value of the regional agricultural output, but allowing for crop water deficits, is first maximized using nonlinear programming. The allocation process then adopts techniques of linear programming to determine the least cost alternative based on the unit cost of water from each resource at each destination, as it varies with time.