中国水土保持科学2024，Vol.22Issue(3)：162-168,7.DOI:10.16843/j.sswc.2022167
基于能量平衡原理的栓皮栎幼苗土壤水分胁迫指数下基线研究
Study on base line of CWSI for Quercus variabilis seedlings based on energy balance principle
摘要
Abstract
[Background]In order to accurately determine the linear regression relationship between leaf temperature difference and atmospheric vapor pressure difference(VPD)of Quercus variabilis seedlings under the condition of adequate water supply,and to optimize the crop water stress index(CWSI)empirical model established by predecessors,Zhengzhou city in Henan province,where plant drought is a significant problem,was selected as the main research area,aiming to analyze and understand the dynamic change of soil water and the response degree of plants in a more representative way,so as to build a more applicable CWSI model and soil water diagnosis model.[Methods]The temperature,solar radiation,leaf temperature difference and atmospheric vapor pressure difference of Q.variabilis seedlings in the pot experiment were measured by dry-wet reference surface method in research base of College of Forestry,Henan Agricultural University.The reasonable upper and lower baselines of CWSI model of Q.variabilis seedlings were determined by theoretical analysis and calculation of energy balance principle.[Results]Under dry reference plane condition,the leaf temperature difference △t干 of Q.variabilis seedlings was significantly positively correlated with solar radiation Q,and the upper baseline of CWSI empirical model was determined as a straight line:△t干=0.007Q+1.621.Under the wet reference plane,there was a negative correlation between leaf temperature difference △t湿 and V(VPD)of atmospheric saturated water vapor pressure difference,and the linear regression relationship was significant.The optimized lower baseline of CWSI empirical model was obtained:△t湿=-1.218 V+1.987.Thus,the CWSI empirical model after optimizing the lower baseline is I=tca-(-1.218V+1.987)/(0.007Q+1.621)-(1.218V+1.987),tca is the measured leaf-air temperature difference.The CWSI value of Q.variabilis seedlings was calculated by using the optimized CWSI model with the obtained upper and lower baseline.The linear relationship between CWSI value I and soil moisture θ was significant.The diagnostic formula is θ=-24.65I+27.91.The relationship between CWSI and soil moisture content was as follows:12％soil moisture corresponded to mild drought,and CWSI was about 0.65.The soil moisture of 8％-10％corresponded to moderate drought,and the CWSI was 0.75-0.8.Soil moisture of 5％-8％corresponds to severe drought and CWSI is 0.8-0.95.When soil moisture was lower than 5％and CWSI was greater than 0.95,the seedling stress was fatal.[Conclusions]The relationship between leaf temperature difference and VPD can be more accurately determined by the heat budget calculation method of energy balance equation,so as to optimize the CWSI model,and then calculate the linear relationship between CWSI of different crops and soil moisture according to this model,and obtain the soil moisture diagnosis model.The soil moisture of different crops or forest plants can be diagnosed according to the solar radiation and air temperature and humidity of remote sensing leaves and weather stations.关键词
叶温/干湿参考面/下基线/CWSI/栓皮栎Key words
leaf temperature/wet and dry reference surface/louer baseline/CWSI/Quercus variabilis分类
农业科技引用本文复制引用
王谦,解英超,李明蔚,李强,陈景玲,寇渊博..基于能量平衡原理的栓皮栎幼苗土壤水分胁迫指数下基线研究[J].中国水土保持科学,2024,22(3):162-168,7.基金项目
国家自然科学基金"基于气候空间上限列线的栓皮栎幼苗高温叠加干旱胁迫机制研究"(31370621) （31370621）
