土壤学报2023，Vol.60Issue(5)：1430-1441,12.DOI:10.11766/trxb202203030009
稻秆碳氮在黑土种稻土壤颗粒有机质中的分配特征
Incorporation of Carbon and Nitrogen from Rice Straw into Particulate Organic Matter in Black Soil with Rice Planting
摘要
Abstract
[Objective]Particulate organic matter is an important component of soil labile organic matter and a sensitive index to evaluate a change of the soil organic matter.The climate in Northeast China is very cold,so,paddy fields therein have a short flooding period and a long non-flooding period since the soil is frozen for most of the time.However,little research has been carried out on the incorporation of exogenous rice straw carbon(C)and nitrogen(N)into particulate organic matter in black soil with different rice planting years.[Methods]A 300-day incubation experiment was conducted,in which dual-isotope-labeled(13C/15N)rice straw was added to a cultivation chronosequence of paddy soils ranging from 0 to 85 years(0 a,12 a,35 a,62 a and 85 a).Flooding incubation experiments were conducted at a temperature of 20 ℃ and a 1 cm water-flooded layer in a laboratory for 150 days while the freezing incubation experiments were also carried out for 150 days under a soil temperature of-15 ℃ and water-saturated.[Result]Throughout the entire incubation period,the contents of particulate organic carbon(POC)and particulate organic nitrogen(PON)in all paddy soils from the samples with and without rice straw were lower than that in the control soil(0 a).The contents of POC and PON in all soils from the samples with rice straw increased after 5 days of flooding incubation,but they did not show a consistently increasing trend in the subsequent incubation period.For paddy soils of different rice planting years,the relative contribution of the added rice straw C(N)to POC(PON)was 0.2％-13.9％(0.4％-3.8％).0.7％-13.8％(1.4％-9.9％).At the end of freezing incubation,incorporation of the rice straw C into POC in control soil(0 a)and 12-year paddy soil(12 a)decreased significantly compared with that at the end of flooding incubation.Also,the added rice straw N into PON in control soil(0 a)and 85-years paddy soil(85 a)decreased while the added rice straw C(N)into POC(PON)in other rice cultivating years was still increasing.The incorporation of the added rice straw C into POC was significantly negatively correlated with soil organic C,total N and alkaline N,and significantly positively correlated with soil C/N,available phosphorus and microbial biomass C.In addition,the incorporation of straw N into soil PON showed a significant negative correlation with soil organic C content.[Conclusion]The study showed that the longer the years of rice planting in a typical black soil of northeast China,the contents of soil organic C,total N and alkaline N were relatively low,while the soil C/N,available phosphorus and microbial biomass C contents were relatively high.The greater the incorporation of straw C and N into soil particulate organic matter,the more the response of soil particulate organic matter to rice straw addition.关键词
双标记(13C/15N)水稻秸秆/颗粒有机碳(氮)/稻田土壤/黑土Key words
Double labeled(13C/15N)rice straw/Particulate organic carbon(nitrogen)/Paddy soil/Black soil分类
农业科技引用本文复制引用
吴怡慧,王鸿飞,张瑞,安晶,张玉玲,虞娜,邹洪涛..稻秆碳氮在黑土种稻土壤颗粒有机质中的分配特征[J].土壤学报,2023,60(5):1430-1441,12.基金项目
国家重点研发计划项目(2017YFD0300707-A04)和国家自然科学基金项目(41571280、41101276、41907005)共同资助 Supported by the National Key Research and Development Program(No.2017YFD0300707-A04)and the National Natural Science Foundation of China(Nos.41571280,41101276,41907005) （2017YFD0300707-A04）
