黄土高原不同年限刺槐土壤化学计量特征分析

发布时间：2018-06-30 04:13

本文选题：黄土高原 + 刺槐人工林　；参考：《水土保持学报》2017年02期

【摘要】：通过对陕北黄土高原4种不同年限(10,15,25,40年)刺槐林地0—200cm土壤的采集与分析,研究不同刺槐种植时间对土壤营养元素及化学计量比的影响。在每个林龄的林地内设3个小区,每个小区采用随机采样法选取3个采样点分层采集土壤样品,进行土壤碳、氮、磷、钾测定,计算化学计量比。结果表明:(1)有机碳和全氮、全钾含量随刺槐年限增加呈基本增大的趋势,全磷随刺槐年限的增长变化不大;有机碳、全氮和全磷呈极显著的正相关关系;(2)在0—200cm土层,有机碳、全氮空间分布基本一致,随土层深度增加均呈先减少后趋于稳定的变化趋势;全磷在整个空间中的分布较为均匀,其空间变异性低于有机碳和全氮;全钾含量高于碳氮磷含量,且随土壤深度变化不大;(3)土壤C∶N比,C∶P比,N∶P比和C∶N∶P比均随刺槐年限的增长呈先降低后升高的趋势,都在15年处有最低值;(4)土壤C∶N比随土层深度在一定范围波动,C∶P和N∶P比均随土层深度的增加呈先减少后趋于稳定的变化趋势。
[Abstract]:The effects of different planting time of Robinia pseudoacacia on soil nutrient elements and stoichiometric ratio were studied by collecting and analyzing the 0-200cm soil of four different years (10 ~ 15 ~ 25, 40 years) in Loess Plateau of Northern Shaanxi. Three plots were set up in each woodland of forest age, and three sampling points were selected to collect soil samples by random sampling method. The soil carbon, nitrogen, phosphorus and potassium were measured and the stoichiometric ratio was calculated. The results showed that: (1) the contents of organic carbon and total nitrogen, total potassium and total potassium increased with the years of Robinia pseudoacacia, but the total phosphorus changed little with the increase of the number of years of Robinia pseudoacacia, organic carbon, total nitrogen and total phosphorus showed a very significant positive correlation, (2) in the soil layer of 0-200cm, there was a significant positive correlation between total phosphorus and organic carbon. The spatial distribution of organic carbon and total nitrogen was basically the same, and the spatial variability of total phosphorus was lower than that of organic carbon and total nitrogen. The content of total potassium was higher than that of carbon, nitrogen and phosphorus, and there was little change with the soil depth. (3) the ratio of C: n to C: P and C: n to P were decreased first and then increased with the increase of the years of Robinia pseudoacacia. (4) soil C: n ratio fluctuated in a certain range with the depth of soil layer. Both C: P and N: P ratios decreased first and then tended to stable with the increase of soil depth.
【作者单位】：西北农林科技大学资源环境学院;西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室;
【基金】：国家自然科学基金项目(41471437) 国家重点研发计划项目(2016YFA0600801) 科技基础性工作专项(2014FY210130) 西北农林科技大学基本科研业务项目(Z109021429)
【分类号】：S714.2

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