马尾松特用林10年土壤肥力演变及特征OA

To compare the changes in soil fertility quality of Pinus massoniana special use forest from pure forest to P.massoniana-Camellia oleifera mixed forest,as well as the application of organic-inorganic compound fertilizer between 2014 and 2024,this study explores the soil chemical indicators that occupy a core position in the soil fertility evaluation model,analyzes the evolution and characteristics of soil fertility,and investigates the effects of mixed forest and organic-inorganic compound fertilizer application on soil fertility.Taking the second-generation seed orchard of P.massoniana in the germplasm gene conservation forest of the state-owned Paiyangshan Forest Farm in Guangxi as an example,the differences in eight soil chemical property indicators,including soil pH,organic matter,total nutrients,and available nutrients,from 2014 to 2024 were analyzed.Two different evaluation methods,the Technique for Order Preference by Similarity to Ideal Solution(TOPSIS)and the Compromise Programming(CP)method,were used for a comprehensive evaluation of soil fertility.The weights of the indicators were determined to construct the evaluation system,and the evolution characteristics of soil fertility were analyzed.The results showed that after the application of organic-inorganic compound fertilizer and the conversion to P.massoniana-C.oleifera mixed forest,the eight soil chemical property indicators improved to varying degrees:soil acidification was alleviated,soil nutrient content increased,supply capacity improved,and soil fertility quality was significantly enhanced.For different mixing ratios of coniferous and broad-leaved trees,the soil fertility quality of the 7∶3 mixing ratio was better than that of the 5∶5 mixing ratio.From 2014 to 2024,the available phosphorus content in the soil increased by 4-8 times,and its grade was raised from level 5 to level 2;the pH value,organic matter,total nitrogen,total phosphorus,total potassium and available potassium content increased to varying degrees,with some grades being raised to level 1;the alkali-hydrolyzable nitrogen content increased,but its grade remained unchanged.The weight distribution of soil chemical indi-cators showed that the four indicators of total phosphorus,available phosphorus,available potassium,and total potassium occupied a central position in the soil fertility evaluation,with prominent weights for potassium and phosphorus.The combination of P.massoniana-C.oleifera mixed forest and organic-inorganic compound fertilizer application can improve soil structure,promote the decomposition and mineralization of nutrients,enhance nutrient utilization efficiency,and optimize soil fertility and water retention capacity,thus forming a virtuous cycle.This is conducive to improving forest land productivity and achieving sustainable develop-ment of the P.massoniana germplasm gene conservation forest.