晋西黄土区不同土壤水分条件下刺槐和侧柏人工林的水分利用来源  

Water source of Robinia pseudoacacia and Platycladus orientalis plantations under different soil moisture conditions in the Loess Plateau of Western Shanxi,China

作　　者：吴应明 韩璐 刘柯言 胡旭 付照琦 陈立欣[1,2] WU Yingming;HAN Lu;LIU Keyan;HU Xu;FU Zhaoqi;CHEN Lixin(Collge of Water and Soil Conseration,Beijing Forestry University,Beijing 100083,China;National Station for Forest Ecosystem Research in Jixian County,Linfen 042200,Shanxi,China)

机构地区：[1]北京林业大学水土保持学院,北京100083 [2]山西吉县森林生态系统国家野外科学观测研究站,山西临汾042200

出　　处：《应用生态学报》2023年第3期588-596,共9页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(41977149)资助。

摘　　要：水分是黄土地区限制植物生长的关键因子,研究不同造林树种在不同水分条件下的水分利用来源对理解干旱半干旱区植物的抗旱机制至关重要。本研究以黄土区主要造林树种刺槐和侧柏为对象,利用稳定同位素(δ^(18)O、δ^(2)H)分析两树种在干旱处理(100%无穿透雨,DT)和自然降雨(CK)下的水分利用深度,探究两树种的干旱适应性。结果表明:在CK中,刺槐在雨月(6、9月)主要利用0~40 cm土壤水,利用率达68.0%±2.4%,旱月(7、8月)均匀利用4层(0~10、10~40、40~60、60~120 cm)土壤水分。而侧柏在雨月和旱月均主要利用0~40 cm土壤水,利用率分别为77.0%±2.4%和57.4%±3.0%。在DT中,随着土壤含水量降低,刺槐和侧柏的水分利用深度下移,其中,刺槐的水分利用深度从0~40 cm转为60~120 cm,侧柏从0~40 cm转为均匀利用4层土壤水。综上,刺槐和侧柏均能在不同水分条件下适应性调整水分利用深度,具有较强的干旱适应性,这对评估当地人工林干旱抗逆性和稳定性具有重要意义。Water is a key factor limiting plant growth in loess regions.Studying water use by different afforestation species under different water conditions is crucial to understand the drought resistance mechanisms of plants in arid and semi-arid regions.We analyzed water use at different depths by the afforestation species Robinia pseudoacacia and Platycladus orientalis under the drought treatment(100%no throughfall,DT)and the natural rainfall(control,CK)by stable isotope(δ^(18)O、δ^(2)H)technique and explored their drought adaptability.The results showed that R.pseudoacacia mainly absorbed soil water at 0-40 cm soil layer in the wet months(June and September),with a contribution rate of 68.0%±2.4%,and at four layers(0-10,10-40,40-60,and 60-120 cm)evenly in the dry months(July and August)in the CK.In contrast,P.orientalis mainly absorbed soil water at 0-40 cm layer in both the wet and dry months,with the contribution rate being 77.0%±2.4%and 57.4%±3.0%,respectively.In the DT,the water-use depths of R.pseudoacacia and P.orientalis tended to move downward with the decreases of soil water content.The water-use depths of R.pseudoacacia changed from 0-40 cm to 60-120 cm,while that of P.orientalis changed from 0-40 cm to the four layers mentioned evenly.R.pseudoacacia and P.orientalis could adjust water-use depths under different water conditions and showed strong drought adaptability,a feature of great significance for evaluating the stress resistance and stability of local plantations.

关 键 词：水分利用来源 氢氧稳定同位素 干旱处理 黄土高原 

分 类 号：S714.2[农业科学—林学] S792.27S791.38