Subjects: Geosciences >> Geography submitted time 2023-11-13 Cooperative journals: 《干旱区地理》
Abstract：作物水分生产率的准确和定量化评价是提高干旱区作物产量的基础，对缓解水资源短缺和农业可持续发展具有重要意义。以塔里木盆地北岸的渭干河-库车河绿洲（渭库绿洲）为典型区域，基于Google Earth Engine（GEE）云平台，通过建立20092020年流域SEBAL遥感蒸散发模型、棉花分布识别模型及估产模型，对流域棉花水分生产率进行评价。结果表明：（1） 渭库绿洲棉花产量从2009年的1610.10 kghm-2增长到2020年的1855.05 kghm-2，增长率为13.20%，棉花种植面积逐年向绿洲边缘延伸，棉花产量重心整体自西向东移动2485 m。（2） 棉花生长期2009年蒸散发均值为686.80 mm，2020年为738.66 mm，整体呈上升趋势，其增长率为7.02%，棉花生长期蒸散发最大值为花铃期和吐絮期，蒸散发较高值主要分布在绿洲内部与塔里木河北岸边缘。（3） 2009年水分生产率均值为0.21 kgm-3，2020年均值为0.25 kgm-3，12 a间水分生产率均值增长率为16%。在空间上，渭库绿洲水分生产率重心在红旗镇自东北向西南移动1832 m，年均移动速度为152.67 ma-1。绿洲棉花水分生产率呈现东西方向大于南北方向扩张趋势，空间分布方向趋势增强，空间格局趋向集聚化。（4） 12 a间产量的增长速度超过了蒸散发的上升速度，促使水分生产率提高。其次，水分生产率与棉花种植面积和合理的水量灌溉技术密切相关，水分生产率高值主要分布于沙雅县新垦农场和新和县桑塔木农场，由于农场规模化种植和集约化管理，促进了棉花增产、农业水资源的稳定分配和高效利用。
Subjects: Geosciences >> Hydrology submitted time 2023-03-14 Cooperative journals: 《干旱区地理》
Abstract： Groundwater is important for regulating the water cycle and ecosystem in arid areas. Understanding and managing groundwater resources is the key to preventing the reduction of river baseflow, ground subsidence and water quality degradation. Therefore, this study analyzed the groundwater chemical parameters and hydrogenoxygen stable isotope characteristics of the Ebinur Lake Basin, Xinjiang, China, and explored the sources of groundwater recharge, dynamic changes of water chemical components in different regions by combining linear regression, two-terminal mixed model and GIS spatial analysis. The results showed that: (1) Different circulation processes of groundwater existed in different areas of the Ebinur Lake Basin, with the largest of hydrogen and oxygen isotopes (δ2 H and δ18O) in the middle and lower reaches of the Bortala and Jing Rivers, followed by the area around Lake Ebinur Basin, and the smallest in the upper Bortala River area. (2) Deuterium excess parameter (d-excess) parameter and hydrochemical composition of groundwater reflected different groundwater recharge mechanisms and influencing factors. Groundwater in the upper Bortala River area was mainly recharged by glacial snow melt water. The main sources of groundwater in the middle and lower reaches of the Bortala and Jing Rivers were surface water and precipitation, which were also greatly influenced by the nature of rock formations, farmland development and irrigation measures. Groundwater around Lake Ebinur Basin mainly came from snow and ice melt and precipitation. The middle and lower reaches and groundwater in the river and lake confluence areas are the key areas for pollution prevention and control and management. (3) Different hydraulic connections existed in underground aquifers. The electrical conductance (EC) of flow system I ranged from 210.00 μS·cm-1 to 2500.00 μS·cm-1 , and the d-excess ranged from 6.47‰ to 9.70‰. The EC of flow system II ranged from 141.60 μS·cm-1 to 5260.00 μS·cm-1 , and the d-excess ranged from 9.61‰ to 17.45‰. In conclusion, this study investigated the driving mechanisms of hydrogen and oxygen isotopes and water chemistry in groundwater in the Lake Ebinur Basin, which provided some theoretical reference for the rational use and scientific development of groundwater resources in the basin.
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2018-09-03 Cooperative journals: 《干旱区研究》
Abstract：水是植物的主要限制性因子之一，不同生活型植物水分来源不同。运用稳定同位素示踪技术，对准东荒漠区5种典型植物梭梭(Haloxylon ammodendron)、白梭梭(H.persicum)、刺旋花(Convolvulus tragacanthoides)、琵琶柴(Reaumuria soongonica)和盐生假木贼(Anabasil salsa)的小枝木质部水及其潜在水源的氧稳定同位素(δ18O)的组成进行测定，采用IsoSource模型分析这5种植物对各潜在水源的利用比例，相似性比例指数定量分析不同植物间水分利用关系。结果表明：5种植物均主要利用土壤水，但其吸水层位不同，梭梭和白梭梭主要利用深层土壤水(140~200 cm)，利用比例分别为73%~87%和43%~74%，吸水层位于140~160 cm；琵琶柴主要利用浅层土壤水(0~80 cm)，利用比例为49%~85%，吸水层位于60~80 cm；盐生假木贼和刺旋花主要利用浅层土壤水(0~60 cm)，利用比例分别为80%~91%和24%~79%，盐生假木贼吸水层位于20~40 cm，刺旋花吸水层位于40~60 cm。梭梭和白梭梭、盐生假木贼和刺旋花两两存在水源竞争的现象。此研究为荒漠地区生态恢复与重建以及对植物在干旱环境下的适应性探索提供参考依据。
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