摘要
长期施肥引起表层和深层土壤水、热、养分和微生物活性的分异,进而影响秸秆碳在土壤中的分解和周转过程。本研究基于沈阳农业大学长期定位实验站,分别将不同施肥处理表层(0~20 cm)和深层(40~60 cm)土壤与;C标记秸秆混合进行田间试验,通过分析团聚体中有机碳含量和δ^(13)C值,对比秸秆碳在表层和深层土壤团聚体中分配的差异,探讨施肥对秸秆碳在土壤团聚体中固定的影响。结果表明:与施肥(包括单施氮肥和有机肥配施氮肥)处理相比,不施肥处理分别使表层土壤<0.053 mm和深层土壤>0.25 mm团聚体中秸秆碳含量增加了106.7%和34.2%;秸秆碳对深层土壤>0.053 mm团聚体有机碳的贡献率约为表层土壤的2.0倍;秸秆碳分配到表层土壤>0.25 mm和<0.25 mm团聚体的比例平均分别为22.6%和11.4%,分配到深层土壤的相应比例分别为29.4%和8.8%。总之,秸秆添加促进了深层土壤大团聚体碳源的更新和固存,提高了深层土壤的固碳潜力。
Long-term fertilization causes the differences in water,heat,nutrients and microbial activities between topsoil and deep soil,with consequences on the decomposition and turnover of straw carbon(C)in soils.At a long-term positioning experimental station in Shenyang Agricultural University,we mixed the topsoil(0-20 cm)and deep soil(40-60 cm)samples from different fertilization treatments with;C-labeled straw for in-situ incubation.We analyzed the content of organic C and itsδ^(13)C value in soil aggregates,compared the difference in the distribution of straw C between topsoil and deep soil aggregates,and explored the effects of fertilization on the sequestration of straw C in soil aggregates.Compared with fertilization treatments(i.e.,single chemical nitrogen fertilizer application and combination of organic manure with nitrogen fertilizer application),the treatment without fertilization increased the content of straw C of<0.053 mm aggregate in the topsoil by 106.7%and that of>0.25 mm aggregate in the deep soil by 34.2%.The contribution percentage of straw C to organic C of>0.053 mm aggregate in the deep soil was about two times of that in the topsoil.About 22.6%and 11.4%of straw C was distributed into the>0.25 mm and<0.25 mm aggregates of topsoil,and about 29.4%and 8.8%of straw C was distributed into the>0.25 mm and<0.25 mm aggregates of deep soil,respectively.In conclusion,straw addition promoted the regeneration and sequestration of carbon in deep soil macroaggregates and increased the carbon sequestration potential of deep soil.
作者
段佳茹
王淑颖
李小红
徐香茹
梅秀文
安婷婷
汪景宽
DUAN Jia-ru;WANG Shu-ying;LI Xiao-hong;XU Xiang-ru;MEI Xiu-wen;AN Ting-ting;WANG Jing-kuan(College of Land and Environment,Shenyang Agricultural University/Key Laboratory of Northeast Arable Land Conservation,Ministry of Agriculture and Rural Affair/National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources,Shenyang 110866,China;College of Agricultural Engineering,Jiangsu University,Zhenjiang 212013,Jiangsu,China)
出处
《应用生态学报》
CAS
CSCD
北大核心
2022年第6期1475-1481,共7页
Chinese Journal of Applied Ecology
基金
辽宁省科学研究经费(LSNQN202008)
国家自然科学基金项目(41977086)
中国博士后科学基金项目(2021M691316)资助。
关键词
团聚体
秸秆碳
深层土壤
C标记
施肥
aggregate
straw carbon
deep soil
13C-labeling
fertilization
