土壤学报2012，Vol.49Issue(1)：77-85,9.
15N标记秸秆在太湖地区水稻土上的氮素矿化特征研究
NITROGEN MINERALIZATION OF APPLIED 15N LABELED STRAW IN PADDY SOILS IN THE TAIHU LAKE REGION
摘要
Abstract
An incubation experiment was conducted to study the distribution of N in mineral nitrogen, microbial bi-omass nitrogen and soil different size fractions after 15N labeled rice straw was added into the wushan and huangni soil. Cross nitrogen mineralization rates of rice straw in the two soils were also measured using 15N isotopic pool dilution technique. Results showed that soil mineral nitrogen decreased between 7 days and 28 days after straw was added into soils. Microbial biomass nitrogen increased before 7 days and changed less after 7 days. Mineral N was the highest at 7 days and accounted for 9. 24% ~ 12. 3% of added straw N. Microbial biomass N was the highest at 14 days and accounted for 21. 3% ~40. 5% of added straw 15N. Mineral "N and microbial biomass 15N decreased between 7 days and 28 days after straw addition, which suggested that straw nitrogen was possibly lost at this time. At 56 days after straw addition, 10. 5% ~ 13. 3% of added straw 15N existed in soil 53 μm -2 mm fraction, 24. 5% -26. 5% was in soil 2-53 μm fraction, and 30% was in <2 μm fraction. 5. 7% ~ 14. 9% of added straw N was lost at 56 days. Straw decomposed more rapidly in the wushan soil than that in the huangni soil, and more straw N was lost in the wushan soil. Cross nitrogen mineralization rates of rice straw in the wushan and huangni soils were 1. 61 and 1. 48 mg kg-1 d-1 at 0. 5 days and were 0. 26 and 0. 36 mg kg-1 d-1 at 56 d after straw addition, respectively.关键词
水稻土/水稻秸秆/15N/微生物生物量氮/土壤颗粒态组分/总矿化Key words
Paddy soil/ Rice straw/ Nitrogen isotope/ Microbial biomass nitrogen/ Soil size fractions/ Cross nitrogen mineralization分类
农业科技引用本文复制引用
闫德智,王德建,张刚,查书平..15N标记秸秆在太湖地区水稻土上的氮素矿化特征研究[J].土壤学报,2012,49(1):77-85,9.基金项目
国家自然科学基金项目(40901140)、中国科学院知识创新工程项目(KZCX2-YW-440)和南通市科技计划项目(BK2011018)资助 （40901140）
