Background Soil and understory vegetation are vital components of forest ecosystems. Identifying the interaction of plantation management to vegetation and soil is crucial for developing sustainable plantation ecosystem management strategies. As one of the main measures of close-to-nature management of forest plantation, few studies have paid attention to the effect of crop tree management on the soil properties and understory vegetation. Methods A 36-year-old Pinus massoniana plantation in Huaying city, Sichuan Province was taken as the research object to analyse the changes in undergrowth plant diversity and soil physicochemical properties under three different crop tree densities (100, 150, and 200 N/ha). Results Our results showed that the contents of available phosphorus, organic matter and hydrolysable nitrogen in the topsoil increased significantly after crop tree management, while content of available potassium decreased. The composition of shrub and herb layer was richer, and the dominant species were obviously replaced after crop tree management. The Shannon–Wiener index and Richness index of shrub layer, and the diversity of herb layer increased significantly after crop tree management. Herb layer diversity indexes and Richness index of shrub layer were closely related to soil organic matter, available phosphorus, hydrolysable nitrogen, available potassium, soil moisture and bulk density. As the main limiting factors for plant growth, nitrogen, phosphorus and potassium were closely related to plant diversity and to the distribution of the dominant species. At the initial stage of crop tree management, each treatment significantly improved the soil physicochemical properties and plant diversity of Pinus massoniana plantation, and the comprehensive evaluation was 200 N/ha >100 N/ha >150 N/ha >CK. Compared with other treatments, 200 N/ha had the best effect on improving the undergrowth environment of the Pinus massoniana plantation in the initial stage of crop tree management.

中文翻译：

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马尾松人工林作物树管理对林下植物多样性和土壤理化性质的早期影响

背景 土壤和林下植被是森林生态系统的重要组成部分。确定种植园管理与植被和土壤的相互作用对于制定可持续种植园生态系统管理战略至关重要。作为人工林贴近自然管理的主要措施之一，很少有研究关注作物林木管理对土壤性质和林下植被的影响。方法以四川省华营市36年生马尾松人工林为研究对象，分析三种不同种植密度（100、150、200 N/ha）下林下植物多样性和土壤理化性质的变化。 ）。结果 我们的结果表明，有效磷含量、农作物管理后表层土壤有机质和可水解氮显着增加，而速效钾含量下降。灌木和草本层的组成更加丰富，作物林管理后优势种明显被取代。作物树管理后灌木层的香农-维纳指数和丰富度指数以及草本层的多样性显着增加。草本层多样性指数和灌木层丰富度指数与土壤有机质、速效磷、水解氮、速效钾、土壤水分和容重密切相关。氮、磷、钾作为植物生长的主要限制因子，与植物多样性和优势种的分布密切相关。在作物树木管理的初始阶段，各处理显着改善马尾松人工林土壤理化性质和植物多样性，综合评价为200 N/ha >100 N/ha >150 N/ha >CK。与其他处理相比，200 N/ha对改善马尾松人工林林木林下生长环境的效果最好。