摘要
川西北沙化草地在围栏禁牧生态恢复过程中,土壤中有机质、全氮、水解性氮变化特征,研究对象为:未修复沙化草地、围栏禁牧生态恢复时间分别为5年、10年的沙化草地,研究其不同围栏禁牧时间沙化草地0~40 cm土层土壤中有机质、全氮、水解性氮的变化。其结果表明,随着围栏禁牧时间的增长,各土层土壤有机质、全氮含量均增加,植被盖度、高度均极显著提高,其中,增加幅度较大的是0~20 cm土层。围栏禁牧10年,沙化草地土壤有机质、全氮含量比未修复沙化草地分别增长34.05%、27.89%,均显著高于未修复沙化草地;各土层土壤水解性氮含量却呈现先减少后增加的特征,其中,0~20 cm土层,围栏禁牧5年沙化草地较未修复沙化草地水解性氮含量减少了23.80%,围栏禁牧10年沙化草地较围栏禁牧5年沙化草地水解性氮含量增加了24.19%;20~40 cm土层,围栏禁牧5年沙化草地较未修复沙化草地水解性氮含量减少了31.49%,围栏禁牧10年沙化草地较围栏禁牧5年沙化草地水解性氮含量增加了1.13%。
In the process of ecological restoration of grazing exclusion desertification grassland in northest Sichuan,the variation characteristics of soil organic matter,total nitrogen and hydrolytic nitrogen in 0−40 cm soil layer of unrestored sandy land,and grazing exclusion grassland with ecological restoration time of 5 and 10 years respectively were studied.The results showed that with the increase of grazing exclusion time,the vegetation coverage and height increased significantly,and the contents of soil organic matter and total nitrogen in each soil layer increased,especially in 0−20 cm soil layer.After 10 years of grazing exclusion,the contents of soil organic matter and total nitrogen in sandy land increased by 34.05%and 27.89%respectively,which were significantly higher than those in unrestored desertification grassland.However,the content of soil hydrolytic nitrogen in each soil layer decreased at first and then increased.In 0−20 cm soil layer,the hydrolytic nitrogen content of the fenced desertification grassland with 5-year grazing exclusion decreased by 23.80%compared with that of the unrestored desertification grassland.Compared with 5-year grazing exclusion sandy grassland,the hydrolytic nitrogen increases by 24.19%in 10-year grazing exclusion sandy grassland.In the soil layer of 20−40 cm,the hydrolytic nitrogen content of sandy grassland with 5-year grazing exclusion decreased by 31.49%compared with that of the unrestored desertification grassland,and the hydrolytic nitrogen content of desertification grassland with 10-year grazing exclusion increased by 1.13%compared with that of the 5-year grazing exclusion desertification grassland.
作者
黄怡
赵聪
杨洋
刘轲
牟秋雨
杨林
胡进耀
HUANG Yi;ZHAO Cong;YANG Yang;LIU Ke;MOU Qiuyu;YANG Lin;HU Jinyao(College of Life Science&Biotechnology,Mianyang Normal University,Mianyang 621000,China;Faculty of Geosciences and Environmental Engineering,Southwest Jiaotong University,Chengdu 611756,China;Sichuan Forest and Grassland Disaster Prevention and Mitigation Engineering Research Center,Mianyang 621000,China)
出处
《四川林业科技》
2021年第1期60-64,共5页
Journal of Sichuan Forestry Science and Technology
基金
四川省教育厅重点项目(18ZA0266)
四川省科技厅项目(2019YFS0167)
东西部大学环境教育类慕课建设比较研究(17YC141)
2018年四川省大学生创新创业训练计划项目(201810639040)。
关键词
有机质
全氮
水解性氮
围栏禁牧
沙化草地
Organic matter
Total nitrogen
Hydrolytic nitrogen
Grazing exclusion
Desertification grassland