柠条锦鸡儿是宁夏干旱风沙区生态重建的主要树种，为明确宁夏干旱风沙区不同季节柠条锦鸡儿在干旱严苛环境条件下的用水策略，该研究采用稳定同位素技术，通过测定柠条锦鸡儿可利用的水源和枝条木质部水分的同位素特征比率，应用 IsoSource模型，从定性和定量角度出发，对比研究不同季节柠条锦鸡儿主要利用水分来源及各水源的贡献率，同时结合土壤水分的补给特征，综合分析柠条锦鸡儿应对干旱严苛环境的适应机制。结果表明:在 0～60 cm 土层，不同季节柠条锦鸡儿土壤含水量差异显著，雨季的土壤含水量均值为14。66%，而旱季的土壤含水量仅为 9。69%。在 80～200 cm 土层，不同季节柠条锦鸡儿土壤含水量差异不显著。不同季节柠条锦鸡儿各水分来源贡献率均不同。在雨季，雨水的贡献率高达 93。00%，而土壤水分贡献率仅为7。00%。在旱季，80～200 cm土层的土壤水，水分贡献率达到 64。10%，0～60 cm 土层土壤水分有部分利用。可见，一定降雨事件影响浅层土壤水分含量，对深层土壤水分影响不显著。不同季节柠条用水策略与各土层土壤含水量的高低有直接关系。雨季，柠条锦鸡儿利用雨水;旱季，柠条锦鸡儿主要利用深层土壤水分，对浅层水分也有一定利用。柠条锦鸡儿在不同季节能通过转化不同水源利用来应对干旱严苛的环境，从而维持自身生长。
Study on water use characteristics of Caragana korshinskii in different seasons in arid sandy area of Ningxia
Caragana korshinskii is the main tree species for ecological reconstruction in arid sandy areas of Ningxia.In order to clarify the water use strategy of Caragana korshinskii in different seasons under drought and harsh environmental conditions in arid sandy areas of Ningxia,this study used stable isotope technology to determine the available water source and the isotope characteristic ratio of xylem water in branches.The IsoSource model was used to compare the main water sources and the contribution rate of each water source in different seasons from a qualitative and quantitative point of view.At the same time,combined with the characteristics of soil water recharge,the adaptation mechanism of Caragana korshinskii to drought and harsh environment was comprehensively analyzed.The results showed that the soil water content of Caragana korshinskii was significantly different in different seasons in the 0-60 cm soil layer.The average soil water content in the rainy season was 14.66%,while the soil water content in the dry season was only 9.69%.In the 80-200 cm soil layer,there was no significant difference in soil water content in different seasons.The contribution rate of each water source of Caragana korshinskii was different in different seasons.In the rainy season,the contribution rate of rainwater was as high as 93.00%,while the contribution rate of soil moisture was only 7.00%.In the dry season,the contribution rate of soil water in the 80-200 cm soil layer reached 64.10%,and the soil water in the 0-60 cm soil layer was partially utilized.It could be seen that a certain rainfall event affects the shallow soil moisture content,but has no significant effect on the deep soil moisture.The water use strategy of Caragana korshinskii in different seasons had a direct relationship with the soil water content in each soil layer.In the rainy season,Caragana korshinskii used rainwater,while in the dry season,Caragana korshinskii mainly used deep soil moisture and also used shallow soil moisture.
water sourcestable isotopeseasonCaragana korshinskiiarid sandy area
万方数据
维普
