黄土区不同退耕方式下土壤碳氮的差异及其影响因素

发布时间：2018-05-17 22:27

本文选题：土壤全氮 + 土壤有机碳　；参考：《应用生态学报》2016年03期

【摘要】：研究植被恢复对土壤碳氮动态的影响,对了解陆地生态系统碳氮循环,应对全球温室效应具有重要意义.本研究以黄土丘陵区不同人工恢复植被为对象,以农田为参照,分析了不同人工植被恢复方式对0~100 cm剖面土壤有机碳(SOC)和全氮(TN)含量影响的差异及其影响因素.结果表明:退耕还林还草显著提高了土壤的SOC和TN含量.退耕后,SOC和TN含量均较农田明显提高.0~100 cm土层SOC平均含量人工乔木林为农田的1.43倍,增幅最大;其次是人工灌木,为1.36倍;最后是人工草地,为1.21倍.0~100 cm土层TN平均含量人工乔木林增幅最大,是农田的1.30倍;其次是人工草地,为1.21倍;而人工灌木增幅最小,为1.13倍.与农田相比,人工恢复植被类型间SOC和TN含量及细根密度的差异在土壤剖面深度上表现出不同,人工乔木和灌木最明显,影响深度100 cm;草地最小,仅为60 cm.恢复植被的细根密度、C∶N和凋落物量显著高于农作物,细根密度与SOC、TN呈显著线性相关(P0.01).细根的质和量以及凋落物量是不同人工恢复植被下SOC和TN含量差异的重要影响因素.
[Abstract]:It is of great significance to study the effect of vegetation restoration on soil carbon and nitrogen dynamics and to understand the carbon and nitrogen cycle in terrestrial ecosystems and to deal with global Greenhouse Effect. In this study, the effects of different artificial vegetation restoration methods on soil organic carbon (SOC) and total nitrogen (TNN) contents in 0 ~ 100cm profile in loess hilly region were analyzed and their influencing factors were analyzed. The results showed that the contents of SOC and TN in soil were significantly increased by returning cropland to forest and grassland. The contents of SOC and TN in artificial Arbor forest were 1.43 times higher than those in farmland, followed by artificial shrubs (1.36 times), artificial grassland (1.36 times) and artificial grassland (P < 0.05). The average TN content of 100 cm soil layer was 1.21 times, which was 1.30 times higher than that of farmland, followed by artificial grassland (1.21 times) and artificial shrub (1.13 times). The differences of SOC, TN content and fine root density between artificial restoration vegetation types and farmland were different in soil profile depth. Artificial trees and shrubs were the most obvious, affecting depth 100 cm, and grassland was the smallest, only 60 cm. The fine root density (C _ (1) N) and litter amount were significantly higher than that of crops, and there was a significant linear correlation between the fine root density and SOCTN (P _ (0.01). The quality and quantity of fine roots and the amount of litter were the important factors influencing the difference of SOC and TN contents in different artificial restoration vegetation.
【作者单位】：西北农林科技大学水土保持研究所;西北农林科技大学资源与环境学院;中国科学院水利部水土保持研究所;
【基金】：国家自然科学基金项目(41371279,41071338)资助~~
【分类号】：S158

【相似文献】