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题名	塔里木河下游铁干里克绿洲水土生态安全及可持续性研究
作者	周洪华
学位类别	博士
答辩日期	2009
授予单位	中国科学院．新疆生态与地理研究所
导师	陈亚宁，新疆生态与地理研究所
关键词	绿洲
其他题名	The study on ecological security of water and soil and their sustainable development of Tikanlik Oasis in the lower Tarim River
中文摘要	绿洲是干旱区人类安身立命的场所、生存繁衍的基地，绿洲的水土生态安全是干旱区可持续发展的关键。本论文针对绿洲生态系统的特点以及其发展过程中日益突出的生态与经济矛盾，以塔里木河下游铁干里克绿洲为例，结合野外调查和室内分析，利用多样性指数、格局分布指数、经典统计方法、聚类分析、地统计方法、Kriging和IDW插值法、土地潜力衰减法、多目标规划模型以及能值分析等数理方法分析了绿洲-荒漠过渡带水-土-植被的关系和绿洲地下水、土壤特性时空动态演变过程，解析了土地利用方式、灌溉方式和种植年限对土壤特性的影响，计算了土壤生产潜力、生态需水量，探讨了绿洲水盐运移规律，确定了维持绿洲-荒漠过渡带稳定和绿洲水土生态安全的合理地下水埋深，提出了保证绿洲外围稳定和绿洲水土生态安全的水资源优化配置方案及可持续发展对策。主要研究结论如下：（1）绿洲-荒漠过渡带植物群落结构简单，物种多样性低，优势种群均呈聚集分布。受地下水埋深的影响，群落结构和物种多样性随着地下水埋深变化呈梯度变化，<4m是维持绿洲－荒漠过渡带群落物种多样性、保护绿洲稳定的合理地下水埋深，9m是绿洲－荒漠带植被生存的极限埋深。（2）利用地统计学和Kriging、IDW插值法等分析发现：绿洲土壤水分含量整体上较低，空间分布不均，土壤盐分含量普遍较高，空间分布格局明显，盐分由深层向表层积聚，具有极强的表聚性，表层土壤盐渍化程度较重。棉田、梨园和人工林地有利于提高土壤水分和养分，改善土壤质量，特别是对表层土壤影响最大；滴灌有助于改善土壤养分条件，有效减轻土壤盐碱化程度，但滴灌后水分携盐扩散将加剧灌溉地周围的非灌溉地表层积盐；种植年限的延长可显著提高10-80cm土壤含水量，减轻0-30cm土壤盐渍化程度，缓解30cm以下土层的碱化程度，增加表层土壤的粘粒含量，但延长种植年限会显著减少土壤碳氮比。（3）研究区土地生产潜力处于较低水平，从空间分布来看，表层土壤水分含量低、盐分含量高的土地生产潜力低于土壤水分含量高和盐分含量少的土地生产潜力。因此，地表水资源缺乏，土壤盐渍化程度较高、土壤水肥较差是造成土壤生产潜力低下的主要原因。（4）受地表水灌溉和地下水大量开采的影响，绿洲地下水埋深较深、矿化度较高的区域主要分布在建筑用地和靠近过渡带的绿洲边缘，地下水埋深较浅、矿化度较低的区域主要分布在灌溉干渠附近的农业耕地，其空间相关性随季节变化逐渐增加。绿洲平均地下水埋深未达到潜水蒸发极限埋深，地下水的强烈蒸发加剧了土壤盐渍化的程度；地下水为中咸水，部分为咸水，不宜饮用和灌溉。因此，铁干里克绿洲不论是潜水位还是水质都处于不安全状态。（5））绿洲土壤水盐运动规律表现为：在水平运动上，土壤盐分向棉田周围扩散、积累，使得棉田周围的荒草地变成干排盐地；在垂直运动上，地下水埋深均在潜水蒸发极限埋深以上，地表蒸发强烈，土壤水分向表层的迁移过程始终存在，因此土壤盐份表聚性强，且花铃期和吐絮期的土壤积盐程度比苗期强烈。水盐过程分析表明，当地下水埋深<6m时，0-50cm土壤盐分含量高，呈T型分布，由地下水通过毛细管作用携带的盐分解释了土壤盐分增加量的90%以上；地下水埋深>6m时，0-50cm土壤盐分急剧下降，呈菱形分布，地表灌溉水的矿化度大小对土壤盐分的积累效应起着决定作用。可见6m是绿洲土壤表层积盐过程停止的临界埋深。（6）不考虑渠道渗漏和蒸发以及生态水文过程等条件下，维持铁干里克绿洲现状的最低生态用水量为129.11×106m3/a；若按目前人口和耕地的变化趋势，要维持绿洲外围稳定和绿洲内水土生态安全，保证绿洲可持续性发展，则在2009年、2015年及2016年恰拉水库必须为铁干里克绿洲下泄水量154.32×106m3、156.64×106m3和180.97×106m3。（7）多目标优化模型和能值分析表明：铁干里克绿洲目前的发展主要依赖不可更新资源，处在以经济发展为主，环境效益次之的结构下，属于消费型经济系统。为实现经济、环境和社会效益的协调发展，必须大力降低社会经济投入，努力提高绿洲本身的自然资源投入，优先保障生态环境的建设，把天然植被的生态用水放在可持续发展的战略高度。其中天然植被的生态用水应占到总耗水量的64%以上，农业耕地灌溉耗水不能超过25%，果园灌溉用水量应保持在11.43%左右，在农业发展上需优先发展林果业等生态环境效益明显的产业。Oasis is the basis of the arid zone. The ecological security of water and soil and sustainable development of oasis is the key of sustainable development of the arid area. Aiming at the characteristics of oasis ecology system and the contradiction between ecology and economy in the oasis development, based on field investigation and laboratory ananlysis, using plant diversity index, parttern index, classical statistical methods, clustering analysis, geo-statistical analysis, Kriging and IDW, the law of potential weaken, mult-objective programming model and emergy, this paper studies the relationship between oasis-desert ecotone water, soil and plant in the Tikanlik oasis of the lower Tarim River, analyzes the spatiotemporal dynamic development of groundwater and soil in the oasis and the effects of land use types, irrigation methods and planting years on soil properties, calculates land potential productivity and water demand, discusses the movement of water and salt in soil, concludes the rational groundwater depth to maintain ecological security of water and soil of oasis and oasis-desert ecotone, puts forward countermeasures for optimizing allotment of water resources and sustainable development of the Tikanlik oasis in the lower Tarim River. The results are as follows: （1）The structure and composition of plant communities were simple and the species diversity of all communities was low in the oasis-desert ecotone. Due to the groundwater depth, all of the dominance population in the study area was aggregation distribution, and the structure, composition and species diversity of all communities showed gradient changes. <4m was the rational groundwater depth to maintain species diversity in oasis-desert ecotone and oasis stability, and 9m was the utmost groundwater depth. （2）the results from the geo-statistics and Krging, IDW ananlysis showed there were low soil moisture and high soil salt in the Tikanlik oasis. The spatiotemporal distribution of soil moisture and soil salt were different with the change in micro-environment. Due to the soil salt accumulating from deep layers to lower layers, soil salinization of the surface soil was severe. Comparative analysis of effects of land use types, irrigation methods and planting years on soil properties showed: cotton land, orchard land and plantation land significantly increased the soil moisture, nutrients, improved the soil structure and quality, especially for the surface soil; drip irrigation was more helpful to improve soil nutrients through decreasing nutrient leaching and significantly alleviated the degree of soil salinization than flood irrigation and non-irrigation, however, the soil salt carried by irrigation water diffused to near non-irrigation land to aggravate the degree of surface soil salinization; prolonged planting years significantly increased the soil moisture of 10-80cm, alleviated the degree of soil salinization of 0-30cm and the degree of soil alkalization of more than 30cm, increased the clay particles in surface soil, however, it would significantly reduces the value of soil C/N ratio. （3） The results calculated from land potential poductivity using the law of potential weaken showed that the land potential productivity was lower in the study area than other areas. The spatial distribution of land potential productivity was consistent with soil moisture and soil salt in the 0-20cm, that was the lower land potential productivity accompanied lower soil moisture and higher soil salt and the higher land potential productivity accompanied higher soil moisture and lower soil salt. Therefore, water scarcity, severe salinization and low soil nutrient were the main factors that led to low land potential productivity in the study area. （4） Due to the effects of surface water irrigation and exploitation of groundwater, the area with deeper groundwater depth and higher mineralization were mainly distributed in the construction land and the edge of oasis, and the area with shallower groundwater depth and lower mineralization were mainly distributed in the cultivated lands, and their spatial dependence increased with the change in seasons. The average groundwater depth in the study area was shallower than the limited depth of groundwater phreatic evaporation which aggravated the soil salinization through the strong evaporation. Moreover, groundwater in the study area was moderate salt water or salt water which was not safe for drinking and irrigating. So, the depth and quality of groundwater in the study area showed an unsafe state. （5） The movement of water and salt in soil showd: soil salt diffused from planting land to around area which became salt deposition lands in the horizontal movement; the average groundwater depth was shallower than limited depth of groundwater phreatic evaporation which aggravated the surface soil salinization through the strong evaporation in the vertical movement. Moreover, the degree of surface soil salinization of flowering and boll-setting period and boll opening stage were more serious than seeding stage of cotton in the Tikanli oasis. Analysis of the process of water- salt movement showed: soil salt of 0-50cm was high and its distribution mainly presented T-type, and the salt carried by groundwater through capillarity explained more than 90% of increasing amount of the surface soil salt when the groundwater depth was less than 6m; soil salt of 0-50cm was significantly decrease and its distribution mainly presented rhombus-type, moreover, mineralization of groundwater decided the salt accumulation in the surface soil when the groundwater depth was more than 6m. So, 6m was the critical groundwater depth which led to stopping surface soil salt accumulation. （6） The lowest ecological water demand from the Qiala reservoir keeping the present state of the Tikanlik oasis was 129.11×106m3/a without involving canal seepage, evaporation and eco-hydrological process; the lowest ecological water demand keeping oasis peripheral stability and ecological safety and sustainable development within oasis in 2009, 2015 and 2016 was 154.32×106m3、156.64×106m3 and 180.97×106m3, respectively, in the Tikanlik oasis. （7） Analyses of multi-goal programming model and emergy ananlysis showed: present development of the Tikanlik oasis mainly depended on non-renewal resources which was belong to a consumptive economy system, that was the top priority development was economy, then was the environment protection. In order to realize the harmonious development of economic benefit, environmental protection and social stability, social economy investment should be reduced, and natural investment of the oasis should be increased, and ecological protection should be developed as a priority to ensure sustainable development in oasis. According to the above, the top priority was ecological water demand of natural plants which was more than 64% of total water consumption in the oasis, and irrigation water demand of cultivated land was less than 25% of total water consumption, and irrigation water demand of forestry and fruit industry kept about 11.43% of total water consumption in the oasis.
语种	中文
学科主题	生态风险评价
公开日期	2010-11-12
页码	共244页
内容类型	学位论文
源URL	[http://ir.xjlas.org/handle/365004/8452]
专题	新疆生态与地理研究所_中国科学院新疆生态与地理研究所(2010年以前数据)
推荐引用方式 GB/T 7714	周洪华. 塔里木河下游铁干里克绿洲水土生态安全及可持续性研究[D]. 中国科学院．新疆生态与地理研究所. 2009.

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