秦岭山区不同种植年限核桃园土壤养分变化特征研究

Changes of Soil Nutrients in Walnut Orchard with Different Planting Years in Qinling Mountain Area

摘要: 为评估秦岭山区长期种植核桃后土壤质量变化特征和土壤养分含量水平，取不同种植年限(5，11，18，20年以上)核桃林土样为研究对象，通过分析土壤肥力主要指标，揭示商洛主要核桃种植区土壤养分演化特征。结果分析表明，核桃园土壤有机质的变化规律为先增加、后降低、再增加。20年以上的核桃种植园土壤有机质含量最高，达到26.04 g/kg。商洛核桃种植园土壤有机质平均含量属于高水平。土壤全氮、全磷变化规律一致，都为先增加、后降低、再增加的趋势，11年种植园的土壤全氮、全磷含量达到最高，分别为1.75、0.91 g/kg，土壤全氮和全磷平均含量均属于高水平。土壤碱解氮含量变化规律为先降低后升高，18年种植园的土壤碱解氮含量最低，为57.97 mg/kg，土壤碱解氮平均含量属于中水平。土壤速效钾含量处于94.22~541.17 mg/kg 之间，变异系数较高，达到48.78%，整体含量处于高水平以上。研究结果可对商洛核桃产业发展提供一定的数据支撑和参考依据。

Abstract: In order to evaluate the change characteristics of soil quality and the level of soil nutrient content after long-term walnut planting in Qinling mountain area, walnut forest soil samples with different planting years (5, 11, 18 and 20 years) were taken as the research object. By analyzing the main indicators of soil fertility, the evolution characteristics of soil nutrient in the main walnut planting areas of Shangluo were revealed. The results showed that the change law of soil organic matter in walnut orchard was first increased, then decreased, and then increased. The content of soil organic matter in walnut Plantation for more than 20 years was the highest, reaching 26.04 g/kg. The average content of soil organic matter in Shangluo walnut plantation is high. The change laws of soil total nitrogen and total phosphorus are the same, which are the trend of first increasing, then decreasing and then increasing. In 11 years, the contents of soil total nitrogen (TN) and total phosphorus (TP) in the plantation reached the highest, which are 1.75 and 0.91 g/kg respectively. The average contents of soil TN and TP belong to a high level. The change law of soil alkali hydrolyzable nitrogen content is first decreased and then increased. The soil alkali hydrolyzable nitrogen content of the plantation in 18 years is the lowest, which is 57.97 mg/kg. The average content of soil alkali hydrolyzable nitrogen belongs to the medium level. The content of soil available potassium is 94.22~541.17 mg/kg, the coefficient of variation is high, reaching 48.78%, and the overall content is above the high level. The results can provide some data support and reference for the development of Shangluo walnut industry.