摘要
Land desertification severely compromises the core function of ecosystem and significantly disrupts biodiversity.Caragana korshinskii Kom.plays a pivotal role as a critical plant resource in the restoration and ecological reconstruction of desertified areas in Northwest China.Kytorhinus immixtus Motschulsky is the primary pest responsible for causing substantial damage to the seeds of C.korshinskii.In this study,field surveys were utilized in three distinct desertified types(lightly,moderately,and severely desertified areas)in north central Ningxia Hui Autonomous Region,Northwest China.This research was focused on investigating the population dynamics and damage rates of K.immixtus,with an emphasis on examining the relationships among K.immixtus distribution,levels of soil desertification,and associated environmental factors.The results revealed marked variations in the population distribution and abundance of K.immixtus across habitats with different degrees of desertification.Due to the sand-fixing ability of C.korshinskii,the severity of soil desertification decreased progressively from severe to moderate and light with C.korshinskii establishment.This reduction in desertification,along with habitat restoration and an increase in plant diversity,was correlated with a gradual increase in K.immixtus population size and damage rate.Generalized linear mixed model analysis revealed significantly positive correlations of soil total potassium,C.korshinskii height,maximum temperature during the survey,precipitation,and the plant species richness index with K.immixtus population.In contrast,the soil total phosphorus content,organic matter content,minimum temperature during the survey,C.korshinskii canopy width,and branch number were significantly and negatively correlated with K.immixtus population.Due to the sand-fixing capacity of C.korshinskii,the plant mitigated soil desertification,but as desertification severity decreased,habitat restoration and increased plant diversity drove a gradual increase in the population and damage rate of K.immixtus.Both biotic and abiotic factors in the habitat significantly influenced K.immixtus occurrence.To achieve the sustainable restoration of desert ecosystem,optimization of plant community structure with soil nutrient management in ecological rehabilitation is necessary to balance the benefits of sand fixation with pest risks.
基金
funded by the National Natural Science Foundation of China(31860619,31560611)
the Natural Science Foundation of Ningxia Hui Autonomous Region,China(2021AAC02009).
作者简介
Corresponding author:ZHANG Dazhi,E-mail:zdz313@nxu.edu.cn。
