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题名	塔里木沙漠公路防护林带土壤水热盐动态及模型模拟
作者	刘海东
答辩日期	2017-05-01
文献子类	硕士
授予单位	中国科学院大学
授予地点	新疆乌鲁木齐
导师	赵英 ; 李生宇
关键词	塔克拉玛干沙漠 咸水滴灌 土壤水热盐动态 数值模拟 Taklimakan Desert Dynamics of soil water and salt Saline water drip-irrigation Numerical simulation
学位专业	农学硕士
英文摘要	In the desert area of Xinjiang, it has a potential to irrigate the shelterbelt using theunderground saline water, however, drought and salt stress could influence the plantgrowth and development. Therefore, understanding of soil water and salt dynamics, as wellas the plant response to the stress is a basis to design the reasonable irrigation schedule.With the field investigation, control experiment and model work together, to analyze thespatial and temporal dynamics of soil heat and salt and the tolerant mechanism of typicaldesert plants under different soil types and water salinities in Taklimakan Desert artificialshelterbelt, HYDRUS-1D is used to simulated soil moisture movement and salt. Mainresults for this study are as follows:The difference of soil water characteristic curve of each soil layer in the test areacorresponds to the difference of physical properties, that is, the features of curve of the soillayer with less content of the slits and clays and the bulk density larger is lower, theopposite is higher. Soil water retention capacity was stronger, which were related to thehigher content of clay particles and the smaller soil bulk density. Two models can be usedto test the soil water characteristic curve fitted, Van Genuchten model has more parameters,the fitting accuracy is higher in low suction less than 1.0×105 Pa, the fitted precision ofGardner model in the suction from 1.0×105 Pa to 15.0×105 Pa is slightly higher, on thewhole, Van Genuchten model fitted effect is better than that of Gardner model.Mean monthly soil temperature under the conditions of different depth of theTaklimakan desert shelterbelt approximate sine curve, and the seasonal alternation effecton temperature in the deeper soil layer is smaller than that of the shallow. The soiltemperature diurnal variation curve of 10~50 cm significantly dynamic than the others, thehighest temperature and the minimum temperature are gradually decline at the beginningof September. The soil temperature was affected by precipitation, 10 cm soil layer has mostsignificant response to rainfall. Compared with the sunny day, there is a significantdifference with change process, but the other layer features of the soil temperature is not obvious difference with sunny days, rainfall directly influenced the daily variationcharacteristics of shallow soil temperature.the soil temperature was basically consistent under different plant types, and the airtemperature was significantly correlated with soil temperature (p<0.01). Meanwhile, thecorrelation of soil temperatures in different soil layers decreased as the soil depth increased.In the soil of artificial shelterbelt, the dynamics of soil water and salt displayed an obviousperiodic rule. With respect to Haloxylon ammodendron, the distribution of soil water andsalt displayed a single-peak curve with the peak appeared at 30 cm in soil depth, while thedistribution of soil water and salt to Calligonum mongolicum showed a single-peak curvewith the peak occurred at 10 cm in soil depth. In the 0~200 cm soil profiles, the soilmoisture is divided into active layer, weak layer, and stable layer in Haloxylonammodendron, but active layer and weak layer in Calligonum mongolicum. The soilwetting front was a semi-ellipsoid shape after drip irrigation. The affected depth ofirrigation water was 0.6 m in Haloxylon ammodendron, while 1.5 m in Calligonummongolicum. The soil salt was concentrated in the upper layer. However, soil salinizationdid not exist due to less than 1.0 mS/cm. The growing season of soil pondage is 116.34 mmin Haloxylon ammodendron, but 100.99 mm in Calligonum mongolicum. All the soil waterdeficit ullage reached more than 270 mm. The plant types had few influences on soiltemperature. The irrigation of Calligonum mongolicum should be properly increased formaintaining the health of shelterbelt system.Hydrus-1D model was used to simulate the dynamics of soil water, heat and salt, thesimulated values of soil water, heat and salt transport were obtained, which can basicallyreflect the time variation law of growing season soil water heat salt. Among them, thewhole simulation of soil temperature in the process of simulation effect is better, the soilmoisture is the second, and the soil salt movement simulation effect is relatively poor. ingeneral, the simulated values can reflect the dynamic changes of soil water and salt indifferent soil layers. Our study is beneficial to provide a suitable irrigation system andapproach, which can ensure the sustainable development of shelterbelt system in Taklimakan Desert.
语种	中文
学科主题	水土保持与荒漠化防治
内容类型	学位论文
源URL	[http://ir.xjlas.org/handle/365004/14886]
专题	新疆生态与地理研究所_研究系统_荒漠环境研究室
作者单位	中国科学院新疆生态与地理研究所
推荐引用方式 GB/T 7714	刘海东. 塔里木沙漠公路防护林带土壤水热盐动态及模型模拟[D]. 新疆乌鲁木齐. 中国科学院大学. 2017.

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