摘要
不合理的垦殖是造成土壤退化的主要原因之一。为了揭示垦殖对高寒草地土壤有机氮组分变化特征的影响,以垦殖1,3,10,16,27,40年后的川西北高寒草地为研究对象,以未垦殖的天然草地为对照,通过土壤采样与分析,研究了垦殖对川西北高寒草地酸解性全氮、酸解铵态氮、氨基糖态氮、氨基酸态氮、酸解未知氮和酸不溶性氮变化特征的影响。结果表明:在川西北高寒草地垦殖过程中,随着垦殖年限的增加,引起了酸解性全氮、酸解铵态氮、氨基糖态氮、氨基酸态氮、酸解未知氮和酸不溶性氮含量的显著下降(P<0.05),特别是在0—20cm土层,分别降低了72.15%,62.72%,66.08%,63.44%,94.00%,51.78%。有机氮组分中下降程度最大的是酸解未知氮。从不同垦殖年限看,酸解性全氮、酸解铵态氮、氨基糖态氮、氨基酸态氮、酸解未知氮和酸不溶性氮含量下降主要发生在垦殖前10年,随着垦殖年限的增加年平均减少率逐渐降低。因此,减少高寒草地垦殖对于促进川西北高原生态系统平衡和高寒草地可持续发展具有重要意义。
Unreasonable cultivation is one of the main causes of soil degradation.In order to reveal the effect of cultivation on the change characteristics of soil organic nitrogen in alpine grassland,this study took alpine meadows of northwestern Sichuan after cultivation for 1,3,10,16,27 and 40 years as research objects and the uncultivated natural grassland as the control.The effects of cultivation on total acid hydrolysable nitrogen(TAHN),acid solution of ammonium nitrogen(ASAN),amino sugar nitrogen(ASN),amino acid nitrogen(AAN),acid hydrolysable unknown nitrogen(AHUN)and acid insoluble nitrogen(NAHN)were studied through soil sampling and analysis.The results showed that the contents of TAHN,ASAN,ASN,AAN,AHUN and NAHN decreased significantly(P<0.05)with the increasing of cultivation years in the alpine grassland in northwestern Sichuan,especially in 0-20 cm soil layer,which decreased by 72.15%,62.72%,66.08%,63.44%,94.00%and 51.78%,respectively.The AHUN was the most significant decrease among the organic nitrogen components.The decrease of TAHN,ASAN,ASN,AAN,AHUN and NAHN mainly occurred in the first ten years of cultivation,and the annual average reduce rate decreased with the increasing of reclamation years.Therefore,reducing the reclamation of alpine grassland is important to promote the ecosystem balance and sustainable development of alpine grassland in the northwest Sichuan Plateau.
作者
何剑锋
胡玉福
杨泽鹏
段皓
凌静
肖海华
舒向阳
李正青
阳帆
李玥萩
HE Jianfeng;HU Yufu;YANG Zepeng;DUAN Hao;LING Jing;XIAO Haihua;SHU Xiangyang;LI Zhengqing;YANG Fan;LI Yueqiu(College of Resources,Sichuan Agricultural University,Chengdu 611130)
出处
《水土保持学报》
CSCD
北大核心
2018年第5期246-251,261,共7页
Journal of Soil and Water Conservation
基金
国家科技支撑计划项目(2015BAC05B01
2015BAC05B02)
国家自然科学基金项目(41771552)
关键词
垦殖
高寒草地
土壤有机氮组分
continuous cultivation
alpine-cold grassland
soil organic nitrogen components
