摘要
在半干旱地区采集7个不同利用方式的土样,利用干筛法获得不同粒径的团聚体,并分析其有机碳、微生物量碳和K_2SO_4浸提碳含量。结果显示,有机碳含量最高的土壤其大团聚体占的比例也最高;未筛分土壤的微生物量碳以灌溉耕地最高、油菜-土豆轮作旱地最低,分别为336和189mg·kg-1。团聚体微生物量碳含量为153～324mg·kg-1。灌溉耕地土壤>5mm团聚体最高,草地土壤<0.25mm团聚体最低。土壤有机碳和微生物量碳在大团聚体(>2mm)中的含量相对都高于小团聚体。微生物量碳与土壤有机碳极显著相关,与K2SO4浸提碳不相关。与微生物量碳相反,K_2SO_4浸提碳含量在<1mm的团聚体中相对较高。
Seven soil samples under different managements were collected from semi-arid area of Inner Mongolia. Soil aggregates were obtained with dry sieving method. The contents of organic C and microbial biomass C were analyzed. The results showed that the soil with highest content of organic C had the highest proportion of large soil aggregates. The content of microbial biomass C in whole soil was highest in irrigated soil and was lowest in cole-potato rotation soil,and the amounts were 336 and 189 mg·kg-1, respectively. Soil microbial biomass C in aggregates ranged from 153 to 324 mg·kg-1, and it was highest in the >5 mm fraction of irrigated soil but lowest in the <0.25 mm fraction of grassland soil. There was a close correlation between soil organic C and microbial biomass C. The large aggregates (>2 mm) contained more higher amounts of both the soil organic C and microbial biomass C than the small aggregates. No significant correlation was found between soil microbial biomass C and K2SO4-extracable C. The small aggregates contained much higher K2SO4-extracable C than the large aggregates. No significant correlation was found between soil microbial biomass C and K2SO4-extracable C.
出处
《中国农业科学》
CAS
CSCD
北大核心
2004年第10期1504-1509,共6页
Scientia Agricultura Sinica
基金
国家"十五"科技攻关资助项目(2001BA508B12)
