干旱地区农业研究2017，Vol.35Issue(3)：272-277,6.DOI:10.7606/j.issn.1000-7601.2017.03.42
三江源区土地利用方式对土壤氮素特征的影响
Effect of land use patterns on soil nitrogen characteristics in Three-river Headwater Area
摘要
Abstract
Four land use pattems,i.e.,alpine meadow steppe,degraded alpine meadow steppe,degraded alpine steppe and artificial grassland,were selected to study effect of land use patterns on the soil nitrogen characteristics.Soil total nitrogen,available nitrogen,ammonium nitrogen,nitrate nitrogen,total inorganic nitrogen (TIN) and its percentage were determined.The results showed that soil nitrogen content of four land use types were all at a lower level.Soil total and available nitrogen of four land use patterns changed similarly in 0 ～ 10 cm soil depth,and the artificial grassland was the highest,the degraded alpine meadow steppe was the lowest.Soil total and available nitrogen in 0 ～ 10 cm soil depth for the degraded alpine meadow steppe decreased 52.4％ and 76.2％ respectively,but those in 10 ～ 40 cm soil increased significantly compared with the alpine meadow steppe.The results of soil ammonium and nitrate nitrogen showed that nitrate nitrogen was the main inorganic nitrogen in soil.Degradation caused both ammonium nitrogen and nitrate nitrogen in 0 ～ 10 cm soil depth decreasing.Both degradation and artificial planting caused nitrate nitrogen decreased in 0 ～ 10 cm soil depth,but increased in 10 ～ 20 cm and 20 ～ 40 cm soil depth,and there was no significant difference between the two soil depth,while soil nitrate nitrogen decreased in 40 ～ 60 cm soil depth.There were no significant differences for both ammonium nitrogen and nitrate nitrogen in 40 ～ 60 cm soil among four land use patterns.Therefore,both degradation and artificial planting caused nitrate nitrogen leaching down in soil profile,and the leaching mainly happened in 0 ～ 40 cm soil depth.Soil total inorganic nitrogen showed a similar trend with soil nitrate nitrogen.The results of total inorganic nitrogen content and the percentage showed that degradation process increased soil nitrogen mineralization.关键词
土地利用方式/高寒草甸/土壤全氮/土壤有效氮/土壤铵态氮/土壤硝态氮Key words
land use patterns/alpine meadow/total soil nitrogen/available soil nitrogen/soil ammonium nitrogen/soil nitrate nitrogen分类
农业科技引用本文复制引用
李亚娟,王亚亚,曹广民,龙瑞军,姚拓..三江源区土地利用方式对土壤氮素特征的影响[J].干旱地区农业研究,2017,35(3):272-277,6.基金项目
国家自然科学基金项目(31360584) （31360584）
甘肃省青年科学基金(1506RJYA027) （1506RJYA027）
