摘要
探讨浑善达克沙地典型乔木青杨和灌木黄柳不同季节的水分利用特征,可为沙地人工防护林生态系统的结构优化提供理论依据。采集研究区大气降水、土壤水、地下水和典型人工固沙植被的茎干水,利用氢氧稳定同位素技术,揭示不同水源δD-δ^(18)O值的分布特征,运用多源线性混合模型计算出各潜在水源对2种植被水的贡献率。结果表明:研究区大气降水方程线为δD=7.84δ^(18)O+9.12,旱季土壤水分线和雨季土壤水分线分别为δD=3.56δ^(18)O-41.28和δD=4.30δ^(18)O-42.02,旱季、雨季土壤水和2种植物茎干水δD-δ^(18)O值均在大气降水δD-δ^(18)O值下方,表明土壤水和茎干水受到二次蒸发的影响较强烈。2种植物浅层土壤含水量受降雨和蒸发的影响强烈,变化幅度较大,随着土壤深度的增加,土壤含水量趋于稳定,且各层土壤水氢氧同位素值表现出显著差异。在旱季,青杨主要吸收利用0~40 cm和120~200 cm土层的土壤水,贡献率分别为50.2%和31.5%;黄柳主要吸收利用20~40 cm和60~100 cm土层的土壤水,贡献率分别为53.2%和22.9%;在雨季,对青杨贡献最大的土壤水主要集中在0~40 cm土层,为72.8%,黄柳除了利用大量0~20 cm土壤水分外,还利用了深层土壤水和地下水。该地区由于乔木青杨和灌木黄柳的根系埋深和分布不同,导致两者在不同季节的水分利用策略存在差异。这有利于浑善达克沙地地区防护林群落稳定和各树种的共存。建议在浑善达克沙地人工防护林种植中,应考虑选择根系埋深和分布不同的植被混种,以合理利用当地水资源,维持沙地生态系统的稳定性。
We examined the characteristics of water use in typical tree species of arbor and shrub in Hunshandake Sandy Land,Populus cathayana and Salix gordejevii,in the different seasons,with the aim to provide theoretical basis for the structural optimization of the artificial shelterbelt.Samples of precipitation,soil water,groundwater and stem water of the two vegetation were collected,and their distribution characteristics ofδD-δ^(18)O were analyzed by hydrogen and oxygen stable isotope technology.The contribution rate of these potential water source to the arbor and shrub species were calculated using multi-source linear mixing model.The precipitation equation line in the study area wasδD=7.84δ^(18)O+9.12,while soil moisture lines in the dry and wet season wereδD=3.56δ^(18)O-41.28 andδD=4.30δ^(18)O-42.02,respectively.TheδD-δ^(18)O of soil water and stem water in the two seasons were lower than the precipitationδD-δ^(18)O,indicating that both of them were strongly affected by the evaporation.Soil water contents in the shallow layer were strongly affected by rainfall and evaporation,with substantial fluctuation.With the increases of soil depth,soil water content tended to be stable,and the hydrogen and oxygen isotope in each soil layer showed significant differences.In the dry season,P.cathayana mainly utilized soil water in 0-40 cm and 120-200 cm layers,with contribution rates of 50.2%and 31.5%,respectively.S.gordejevii mainly absorbed soil water in 20-40 cm and 60-100 cm layers,and the contribution rates were 53.2%and 22.9%,respectively.In the wet season,the greatest contribution of soil water to P.cathayana was mainly in the 0-40 cm soil layer,accounting for 72.8%.S.gordejevii was mainly in the 0-20 cm soil water,evenly utilized the deeper soil water and groundwater.Due to the differences in root depth and distribution of the arbor and shrub,their water use strategies differed in different seasons,which was conducive to the stability of the shelterbelt community and tree species coexistence in Hunshandake
作者
苏文旭
贾德彬
高瑞忠
卢俊平
卢方园
赵航
王芳
SU Wen-xu;JIA De-bin;GAO Rui-zhong;LU Jun-ping;LU Fang-yuan;ZHAO Hang;WANG Fang(Institute of Water Conservancy and Civil Engineering,Inner Mongolia Agricultural University,Hohhot 010018,China;Inner Mongolia Key Laboratory of Water Resources Protection and Utilization,Hohhot 010010,China)
出处
《应用生态学报》
CAS
CSCD
北大核心
2021年第6期1980-1988,共9页
Chinese Journal of Applied Ecology
基金
国家自然科学基金项目(51869018)
内蒙古自治区自然科学基金项目(2017MS0513)资助。
关键词
浑善达克沙地
青杨
黄柳
同位素
水分来源
Hunshandake Sandy Land
Populus cathayana
Salix gordejevii
isotope
water source
