基于稳定同位素技术的果草吸水深度研究:以洛川塬不同果−草复合系统为例  

Study of the water absorption depth of fruit trees based on stable isotope technology:Using the different fruit-grass complex systems in Luochuan Loess Tableland as an example

作　　者：张露[1] 赵妮 戈建珍 程积民[1,3,4] 金晶炜[1,3,4] ZHANG Lu;ZHAO Ni;GE Jianzhen;CHENG Jimin;JIN Jingwei(College of Grassland Agriculture,Northwest Agriculture and Forestry University,Yangling 712100,Shaanxi,China;LICA United Technology Limited,Beijing 100085,China;Institute of Soil and Water Conservation,Northwest Agriculture and Forestry University,Yangling 712100,Shaanxi,China;Institute of Soil and Water Conservation,Chinese Academy of Science and Ministry of Water Resources,Yangling 712100,Shaanxi,China)

机构地区：[1]西北农林科技大学草业与草原学院,陕西杨凌712100 [2]北京理加联合科技有限公司,北京100085 [3]西北农林科技大学水土保持研究所,陕西杨凌712100 [4]中国科学院水利部水土保持研究所,陕西杨凌712100

出　　处：《草业科学》2021年第4期726-737,共12页Pratacultural Science

基　　金：国家自然科学基金项目(31601987);国家现代农业产业技术体系(CARS-34);陕西省自然科学基础研究计划项目(2016JM3019、2013JQ3013);国家重点研发计划项目(2016YFC0500704)。

摘　　要：洛川塬水资源短缺、水分利用效率低,因而水分已成为洛川塬果业可持续发展的瓶颈。因此,精确测量植物的吸水深度,分析植物对不同深度土层的水分利用情况,对改进、推广果园土壤管理具有重要意义。本研究利用稳定氢氧同位素技术,研究洛川塬不同果−草复合系统[苹果(Malus domestica)−白三叶(Trifolium repens)和苹果−黑麦草(Lolium perenne)]中果树木质部水以及白三叶、黑麦草茎部水与不同层位土壤水氢同位素比率δD值特征,分析探讨不同果−草复合系统对果树水分来源及对不同层位土壤水分利用的影响。结果表明:在5月,白三叶和黑麦草分别提高0−50和50−100 cm土层的土壤含水量,且水分均来源于10−20 cm土层,与果树不存在水分竞争,同时白三叶和黑麦草均提高果树对40 cm以下土壤水的利用率,增幅分别为27%和9%;在7月,白三叶、黑麦草的水分主要来源于浅层和深层土壤,与果树存在水分竞争,但白三叶与果树的竞争效应小于黑麦草。同时,白三叶和黑麦草分别提高果树对40 cm以下土壤水和0−20 cm土壤水的利用;在8月和10月白三叶提高0−50 cm土层的土壤含水量,以及果树对0−40 cm土壤水的利用率。结果说明,种植白三叶比黑麦草能更好地调节果树水分利用层位及各土壤层位的利用率,使果树最大程度吸收水分。研究结果为揭示土壤−植物系统水分循环的驱动机制奠定基础,也为洛川塬果−草复合系统林下间作牧草品种的选择、果园水分优化管理提供科学依据。Water resource shortage and low water use efficiency are the limiting factors of sustainable development of the fruit industry in the Luochuan Loess Tableland. Therefore, it is important to accurately measure the water absorption depth of plants and analyze their water utilization at different soil depths to improve and promote soil management in orchards. In this study, the stable hydrogen and oxygen isotope technique was used to study the characteristics of δD values(hydrogen isotope ratio) of the xylem water of apple trees, stem water of white clover and ryegrass, and soil water under different depths in different apple trees–grass intercropping systems(apple–white clover and apple–ryegrass) in the Luochuan Loess Tableland and to explore the effects of apple trees–grass intercropping systems on the water sources of apple trees and soil water use in different depths. The results showed that in May, white clover and ryegrass increased the water content in the 0-50 cm and 50-100 cm soil depths, respectively, with water originating from the 10-20 cm soil depths, and there was no water competition with fruit trees. White clover and ryegrass increased the water use efficiency of fruit trees in the soil below 40 cm by 27% and 9%, respectively. In July, the main water of the white clover and ryegrass originated from shallow and deep soils, with water competition with fruit trees. However, white clover experienced less competition with fruit trees than with ryegrass. White clover and ryegrass improved soil water use below 40 cm and 0-20 cm by fruit trees, respectively. In August and October, white clover increased the water content of the 0-50 cm soil depths and the utilization rate of the 0-40 cm soil water by fruit trees. Therefore, planting white clover could better adjust the water utilization level of fruit trees and the utilization rate of each soil level than ryegrass. Thus, fruit trees could absorb water to a greater extent. Results from this study provide a basis for understanding the driving mechanis

关 键 词：稳定氢氧同位素 水分来源 白三叶 黑麦草 苹果园 洛川塬 

分 类 号：S66[农业科学—果树学] S54[农业科学—园艺学]