【作者】 陈兆波；

【导师】 洪绂曾；

【作者基本信息】 中国农业科学院 ， 农业资源与利用， 2008， 博士

【摘要】 塔里木河流域地处我国西北内陆干旱地区,当前日趋紧张的水资源与持续恶化的生态环境已经成为制约流域社会经济可持续发展的瓶颈。流域农业用水比重约占总用水量的95%,严重挤占生态用水,且农业用水效率较低。因此,在保证流域粮食安全、生态安全和战略水安全的前提下,提高农业用水效率,减少农业用水量,成为解决流域农业用水与生态环境用水矛盾,缓解流域水资源紧缺与生态环境恶化局面的关键所在。本研究针对该流域农业用水效率偏低,种植结构不尽合理,耗用水量过大等问题,在对流域水资源、农业用水和种植业结构分析的基础上,建立基于水资源高效利用的农业种植结构多目标优化模型及其优化评价指标体系,并探讨流域农业种植结构优化宏观调控机制,以期为今后流域乃至干旱荒漠绿洲区农业种植结构规划和政策分析提供理论依据。1、通过对塔里木河流域相关水行政管理部门、基层技术人员及农户半结构访谈、问卷调查和现场勘察等方式,获得了流域种植结构、农业用水及生态环境等方面的基础数据、流域发展规划及其统计资料。调查结果表明:塔里木河流域粮、经、饲种植面积比例不够协调,饲料作物种植面积过小;高耗水作物种植面积偏大,水分生产效益较低;以往种植结构调整时对种植业的社会效益及其生态效益考虑不够,更未针对流域极度干旱的气候特点,从提高水分生产效益出发,建立基于水资源高效利用的农业种植结构。2、借鉴可持续发展理论、系统工程理论等种植业结构优化理论,以水资源高效利用为核心,以总净产值最大、粮食产量最大、生态效益最大及水分生产效益最大为目标,以耕地面积、可利用农业水资源量、社会需求、种植业净产值等5个方面的8个条件为约束,建立了基于水资源高效利用的塔里木河流域种植结构多目标优化模型。并选取流域重要的农牧业县—温宿县为例,采用能快速、直接求得全局非劣解集的粒子群算法对模型进行了求解。结果表明:通过作物种植结构的合理优化,在保证种植业总净产值、粮食总产量、生态效益及水分生产效益均得到一定程度提高的情况下,仍能获得比较显著的节水效益;2005年流域种植业灌溉用水总量为245.43亿m3,利用温宿县的优化计算成果,若不进行种植结构优化,预计流域2010年和2015年种植业灌溉水量分别需要241.25亿m3和225.49亿m3,而通过种植结构优化,种植业灌溉用水量可大幅消减,2005年实际只需要208.29亿m3,而2010年和2015年分别下降为192.60亿m3和181.29亿m3。节约的水资源量在满足快速增长的工业用水和生活用水需求的同时,也可为持续恶化的流域生态环境提供一定的生态环境用水量。3、作物种植结构优化调整的后效性评价是种植结构优化调整的重要组成部分,论文建立了由目标层、准则层、指标层3个层次所组成的评价指标体系。评价指标体系以流域种植结构优化合理度为目标层,设置了水资源利用高效性、社会公平性、经济合理性及生态安全性4个准则层,共计24项基础性指标。利用改进的层次分析法,采用MATLAB编程对建立的评价模型进行了求解。评价结果表明,通过作物种植结构优化,2005年、2010年和2015年优化后的种植结构合理程度分别较优化前提高了24.8%、23.2%和26.3%。因此,所采用的种植结构优化方案使种植业获得了一定的经济、社会和生态环境效益,并大大提高了水资源利用率和利用效率,证明种植结构优化结果是合理的、可行的。4、在分析塔里木河流域种植结构优化调整的阻碍因素,如农村土地生产经营分散、流域各行政区域存在用水利益冲突、农业用水水价低与用水户科技文化水平低下等基础上,提出只有探索并逐步建立健全市场与计划相结合机制、农业有机补偿与激励机制、农业科技投入机制、社会参与机制、土地流转机制以及以销定产等优化机制,才能保证农业种植结构优化调整方案的有效实施。更多还原

【Abstract】 The Tarim Watershed is located in the inland arid regions of Northwest China. The water scarcity and continuing deterioration of ecology have recently become the main restricting factors to sustainable socio-economic development in this area. Agricultural water accounts for about 95% of total water consumption, which lead to a shortage of ecological water, and the water use efficiency was quite low. So, based on ensuring food security, ecological security and water security, increasing efficiency of agricultural water use and decreasing consumption of agricultural water became the key factors to solve conflict between agricultural and ecological water consumption and alleviate the water shortage and ecological deterioration in the basin. In this study, for important issues of low efficiency of agricultural water use, unreasonable planting structure and excessive water consumption, a multi-objective optimization model based on the high water utilization efficiency and its corresponding evaluation system were built by analyzing the water resources, agriculture water consumption and planting structures in Tarim watershed. The macro-control mechanism of agro-planting structures optimization was addressed to provide theoretical basis for planning and policy analysis of future agro-planting structures in the basin, even in the arid desert oasis area.1. Through semi-structure interview, questionnaire investigation and on-site investigation among water administrative departments, technicians and farmers, a large number of information and data such as planting structures, agricultural water consumption, environment, developing planning and statistical data in the basin were collected. The survey results showed that the panting ratio of grain, economic crops and forage crops lack of coordination. The forage crops cultivation proportion was too small and the cultivation area of high water consuming crops was too large and so the water production efficiency was too low. The social and ecological benefits were hardly considered, and the agricultural planting structures based on high efficient water resource utilization were not founded to counter the problems of the extremely dry climate and increase the water-use production.2. Draw on the theories of sustainable development, system engineering and crop planting structure optimization, taking high efficient water resource use as core aim, considering the largest net output, the heaviest food yield, the biggest ecological benefits and the highest water production, a multi-objective model based on high water use efficiency and planting structure optimization in Tarim watershed was built, in which eight constraint conditions were selected from five aspects such as farmland area, the amount of water resources useable for agriculture, social demand, the net output of planting industry. Taking Wensu, an important agricultural county in this basin, for example, the solution was got by using PSO (particle swarm optimization) method of the whole set non-inferior solution model. The results showed that optimizing the agricultural planting structure can still lead to high water-saving benefits, while the net output of planting industry, total grain yield, ecological efficiency and water use production were increased to some extent. The total amount of water consumption for planting industry was 24.543 billion cubic meters in 2005. According to the results of optimizing simulation of Wensu, if the planting structure was not optimized, the planting industry will consumpt 24.125 billion cubic meters water in 2010 and 22.549 billion cubic meters water in 2015. Otherwise, after optimization, the total water consumption amount for planting industry could be reduced to 20.829 billion cubic meters in 2005, 19.260 billion cubic meters in 2010 and 18.129 billion cubic meters in 2015. The saved water could not only meet the rapid growth in the water use for industry and daily life, but also provide some water for the ecology which are suffering continued deterioration in the basin.3. The benefits assessment was an important part for optimizing the planting structure. A 3-layer evaluation system was set up, including the target layer, rule layer and index layer. The target layer was the planting structures rationality. There are 4 aspects in rule layer, such as the high use efficiency of water resources, social equality, economic rationality and ecological security. The index layer contains 24 basic indexes. Using the methods of AHP (improved analytic hierarchy process) and MATLAB procedure to solve the evaluation model, the results showed that after the optimization for the planting structure, the rationality of planting structure increased by 24.8% in 2005, 23.2% in 2010 and 26.3% in 2015 respectively compared to those before. At the same time, by optimizing the planting structure, the economic, social and ecological benefits of the planting industry were increased to some extent, and the utilization efficiency of water resources was improved significantly. Tanking together, it was feasible to make planting structure optimized. The results of optimizing the planting structure were proved to be reasonable and feasible.4. Base on analyzing the obstacles for optimizing the planting structure in Tarim watershed, such as the dispersion of rural production, conflict among different administrative regions, low price of agricultural water and low literacy levels of local farmers, we proposed that if only gradually establishing and improving mechanism of plan and market combination, compensation and motivation for agriculture, sci-tech investment in agriculture, land transferring, social participation and optimal sale-order-production et al., the optimization of planting structure could be effectively implemented.更多还原