KMS XINJIANG INSTITUTE OF ECOLOGY AND GEOGRAPHY，CAS
| 焉耆盆地土壤水盐分布及灌田水盐动态过程模拟 | |
| 李海霞 | |
| Subtype | 硕士 |
| Thesis Advisor | 杨井 ; 陈亚宁 |
| 2017-05-01 | |
| Degree Grantor | 中国科学院大学 |
| Place of Conferral | 新疆乌鲁木齐 |
| Degree Discipline | 理学硕士 |
| Keyword | 焉耆盆地 土壤水盐 空间变异 Hydrus-1D模型 Yanqi basin soil water soil salt spatial variability Hydrus model |
| Abstract | The Yanqi basin, located in the arid area of Northwest China oasis, includes four county and a number of agricultural farms. The groundwater and surface water resources in the Yanqi basin provide a solid base for the economic development of Southern Xinjiang. In the Yanqi basin, the rainfall is low, the evaporation is large, and the unreasonable irrigation leads to the accumulation of salt on the soil surface. Soil salinization has seriously threatened the sustainable economic development and ecological security of the Yanqi basin.This paper takes Yanqi County thoroughbred field and the Yanqi basin as an example, to study the temporal changes of soil moisture and soil salinity and their spatial variabilities and distributions. This was done by combining field measurement campaign, lab analysis and soil water and salt modelling with Hydrus-1D. The Hydrus-1D model was used to simulate soil moisture and salinity transport for two irrigation scenarios. We get the best irrigation scheme. The main conclusions include: (1) Soil sample analysis shows that sulfate chloride is the main component of the soil salinity in the Yanqi basin.The total salt and Cl-, SO42-, Na+, K+, Ca2+ are positively correlated, the first principal component represents the soil structure and salt composition, and the second principal component represents the pH of the soil.(2) The spatial variability analysis shows that the soil salt content of each layer was more consistent with the Gauss model, and the spatial correlation of surface soil salinity was weak. The spatial variability of surface soil moisture was moderate, and the spatial variability of soil moisture in the other layers was very weak. (3) The soil salinity increases gradually from the west to the east, and gradually increases from the north to the south of Kaidu river. The range of non-salinization increased with the increaseing soil thickness, Soil moisture shows a trend of increasing from the west to the east. (4) The soil salinity concentrates in the boundary of the oasis and in the drainage area. (5) For soil temperature with a film and without a film: at 0~70cm it varies like a cosine function. The soil temperatures of a film is higher than without a film. (6) For soil water content with a film and without a film: at 0~50cm it varies like a cosine function; The soil water content in upper soil layer is greatly affected by root system, at 0~50cm soil salt varies like a cosine function, it is relatively stable at 50~70cm for both with a film and without a film.(7) There is a positive relationship between soil temperature and air temperature, and the influence of atmospheric temperature on soil temperature is weakened with the increase of soil depth. Overall, with the increase of temperature, the water content with a film and without film gradually decreases, and the salt content with a film and without a film decreases. (8) The study area was set up with Hydrus-1D model, then calibrated and validated with the measured soil water and salt of July 1, 2016 to September 9, 2016. In addition, based on the developed irrigation scenarios, the study compared the effects of different irrigation scenarios on the soil moisture and salility, and recommended the suitable irrigation schemem. |
| Other Abstract | 焉耆盆地属于西北干旱区绿洲的一部分，含有四县及多个农、团场。焉耆盆地内地下水和地表水资源比较多，为南疆的粮食发展提供了坚实的后盾。焉耆盆地降雨稀少、蒸发量大、不合理的灌溉等都会导致盐分积聚在绿洲表层，土壤盐渍化已经严重威胁了焉耆盆地经济可持续发展以及生态安全。本研究以焉耆盆地和焉耆县的灌田为研究对象，讨论焉耆盆地土壤水盐的空间分布和灌田土壤水盐的动态变化，通过对土壤水盐的研究，构建适合焉耆盆地灌田土壤水盐的Hydrus-1D模型，将验证好的模型进行土壤水盐模拟，并用模型对制定的2种灌溉方案进行土壤水盐比较，得出适合该灌田的灌溉方案。本次研究得出的主要结论：(1) 焉耆盆地的土壤盐分类型主要为硫酸盐-氯化物，总盐与Cl-、SO42-、Na+、K+、Ca2+、Mg2+呈正相关，经过主成分分析可知，第一主成分代表了土壤结构与盐分组成，第二主成分代表了土壤的酸碱性。(2) 空间变异性分析发现，每层土壤盐分都比较符合高斯模型，表层土壤盐分空间相关性弱，其余层的空间相关性呈中等。表层土壤水分的空间变异为中等，其余各层土壤含水量的空间变异非常弱。(3) 土壤盐分由西向东逐渐增多，从开都河北岸向开都河南岸呈现逐渐增多的规律。随土壤深度的加深，非盐化面积增多；土壤水从焉耆盆地的西部向东部逐渐增多。(4) 土壤盐分在绿洲边缘和排碱渠内聚集，没在绿洲内聚集。(5) 从土壤的温度日变化趋势中可以看出：有膜和无膜0~70cm表现形式近似为余弦函数，有膜土壤温度比无膜土壤温度要高。(6) 有膜和无膜0~50cm土壤水分呈现余弦函数的变化趋势，上层土壤水含量受根系影响很大，有膜和无膜0~50cm土层盐分随时间的变化呈余弦函数变化，有膜和无膜50~70cm盐分的变化相对其他土层变化相对平缓。(7) 土壤温度与大气温度呈正相关，随着土壤深度的加深，大气温度对土壤温度的影响减弱，各层土壤温度之间的差距逐渐减小。在整体上无膜、有膜土壤含水率随温度逐渐上升而逐渐下降，在整体上无膜、有膜土壤盐分随温度随逐渐上升而下降。(8) 建立了研究区Hydrus-1D模型，并应用2016年7月1日~9月9日的土壤水盐的实测结果对模型进行校准和验证，并确立了研究区的Hydrus-1D模型，另外，以焉耆盆地的典型农作物辣椒为例，就辣椒生育期需水量和当地农户实际的灌溉，通过模型对这两种灌溉方案进行比较，得出比较合适的灌溉方案。 |
| Subject Area | 自然地理学 |
| Language | 中文 |
| Document Type | 学位论文 |
| Identifier | http://ir.xjlas.org/handle/365004/14881 |
| Collection | 研究系统_荒漠环境研究室 |
| Affiliation | 中国科学院新疆生态与地理研究所 |
| First Author Affilication | 中国科学院新疆生态与地理研究所 |
| Recommended Citation GB/T 7714 | 李海霞. 焉耆盆地土壤水盐分布及灌田水盐动态过程模拟[D]. 新疆乌鲁木齐. 中国科学院大学,2017. |
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