平陆运河沿岸荔枝古树健康评价及其土壤影响因素研究OA

To address the conservation needs of ancient and notable trees in the context of the Pinglu Canal construction,this study assessed the health status and soil nutrient conditions of ancient lychee trees(Litchi chinensis Sonn.)in the Qinzhou section along the canal.The objective was to provide a scientific basis for the in-situ protection and maintenance management of these trees during canal development.Taking 59 ancient lychee trees within the in-situ protection zone of the Pinglu Canal as research subjects,the study employed field surveys and principal component analysis(PCA)to determine tree health grades.Rhizosphere soil samples were collected for chemical property testing,and correlation analysis and redundancy analysis(RDA)were used to explore the asso-ciations between soil nutrients and tree health indicators.The results indicated that:(1)the overall health of the ancient lychee trees in the study area was generally poor,with only 28.81%of the individuals classified as healthy;(2)tree vigor,crown shape,pests and diseases,and leaf color were critical factors influencing the healthy growth of the trees;(3)soil nutrient status,particularly soil or-ganic matter(SOM),total nitrogen(TN),and ammonium nitrogen(AN),showed significant correlations with tree health grades;and(4)according to the standards of the Second National Soil Survey,soil carbon and potassium levels in the study area were moderate,while nitrogen content was generally low.The severely damaged trees exhibited the lowest levels of SOM and nitrogen.Consequent-ly,future maintenance and management should prioritize targeted fertilization to address soil nutrient deficiencies and improve soil nutrient status.