气候变化对草甸草原土壤氮素矿化作用影响的实验研究  

FIELD EXPERIMENTAL STUDIES ON THE EFFECTS OF CLIMATE CHANGE ON NITROGEN MINERALIZATION OF MEADOW STEPPE SOIL

作　　者：王其兵[1] 李凌浩[1] 白永飞[1] 邢雪荣 

机构地区：[1]中国科学院植物研究所植被数量生态学开放研究实验室，北京 100093

出　　处：《植物生态学报》2000年第6期687-692,共6页Chinese Journal of Plant Ecology

基　　金：国家重大基础研究项目(G1999043407);国家自然科学基金重点项目(39730110);中国科学院内蒙古草原生态系统定位研究站开放基金(9806)

摘　　要：用盖顶 PVC管法 ,将锡林河流域中 146 9m高海拔处的草甸草原原状土柱分别移植到海拔 1187m、96 0 m的低海拔处培养 ,用以研究温度变化对土壤氮素的净氨化速率、净硝化速率和净矿化速率的可能影响。经过一个生长季培养后的测定结果表明 :从高海拔到低海拔 ,实验所选择的 3个地点的年均气温分别为 - 0 .5℃、2 .2℃和 4.4℃ ,受此不同气温的影响 ,移植到这 3个地点的草甸草原土壤氮素的净氨化速率分别为 0 .0 5 mg N.kg- 1 .m- 1 ,0 .13mg N.kg- 1 .m- 1和 1.0 9mg N.kg- 1 .m- 1 ;净硝化速率分别为 0 .0 5 mg N.kg- 1 .m- 1 ,0 .76 mg N.kg- 1 .m- 1和 0 .2 6 mg N.kg- 1 N.m- 1 ;净矿化速率分别为 0 .10 m g N.kg- 1 .m- 1 ,0 .89mg N.kg- 1 .m- 1和 1.35 mg N.kg- 1 .m- 1。We assessed the potential impact of global warming on rates of net ammonification, net nitrification and net mineralization of soil nitrogen by transferring intact soil cores (0 15 cm) from 1469 m higher elevation meadow steppe to 1187 m and 960 m lower elevation sites respectively in the Xilin River Basin of Inner Mongolia. After incubation for one growing season, ammonium nitrogen and nitrate nitrogen (including nitrite nitrogen) of the soil samples were determined.The annual mean air temperature at the three selected study sites during the field study was, from higher to lower elevation, -0.5°C, 2.2°C and 4.4°C respectively.Affected by these different air temperature regimes, the net ammonification rate was 0.05 mgN·kg -1 ·m -1 ,0.13 mgN·kg -1 ·m -1 ,1 09mgN·kg -1 ·m -1 .Correspondingly,the net nitrification rate was respectively 0.05mgN·kg -1 ·m -1 ,0.76 mgN·kg -1 ·m -1 and 0.26mgN·kg -1 ·m -1 ,and the net mineralization rate was 0.10mgN·kg -1 ·m -1 , 0.89mgN·kg -1 ·m -1 and 1.35 mg N·kg -1 ·m -1 in the soil transferred to the three sites. Hence we conclude that increasing air temperature will enhance soil N mineralization.

关 键 词：草甸草原 温度变化 土壤移植 土壤氮素 矿化作用 

分 类 号：S812.2[农业科学—草业科学]