生态学报2018，Vol.38Issue(11)：3848-3858,11.DOI:10.5846/stxb201705311002
长期施肥下农田土壤-有机质-微生物的碳氮磷化学计量学特征
Carbon, nitrogen, and phosphorus stoichiometry characteristics of bulk soil,organic matter, and soil microbial biomass under long-term fertilization in cropland
摘要
Abstract
Investigating the impact of exogenous input of nutrients on the stoichiometric ratio of carbon (C),nitrogen (N),and phosphorus (P) in arable soil is of significance for better understanding of the cycling and interaction of C and N in agroecosystems.Based on a 26-years fertilization experiment in a cropland,we analyzed content and stoichiometric ratio of C,N,and P in bulk soil,soil organic matter,and microbial biomass under various fertilization treatments.The regulation coefficient,H was calculated according to the model y =c x1/H,where y is consumer stoichiometry,x is resource stoichiometry,c is a constant and H is regulation coefficient.Results showed that,compared with fallow (CK0),soil microbial biomass nitrogen under the manure treatments (MNPK and 1.5MNPK) with cropping,significantly decreased,but soil microbial biomass phosphorus was significantly increased (P ＜ 0.05).Long-term application of chemical fertilizers significantly decreased organic P.The C ∶ N ratio in bulk soil,soil organic matter,and soil microbial biomass under treatments with organic amendments (maize straw and livestock manure) was significantly lower than that of the chemical fertilization treatments (N,NP,PK,and NPK).Compared with CK0 treatment,application of P (chemical P fertilizer or organic amendments) significantly reduced C ∶P ratio in bulk soil and soil microbial biomass,but no fertilization (CK) and unbalanced fertilization treatments (N,NP,and PK) significantly decreased C ∶P ratio of soil organic matter.The N ∶P ratio under CK0 treatment was the highest of all treatments.Moreover,N ∶P ratio of soil organic matter under CK0 treatment was higher than that of the CK and the chemical fertilization treatments,indicating the N depletion in soil organic matter under CK and chemical fertilization treatments.The homeostatic regulation coefficient H of C ∶N,C ∶P,N ∶P was 0.24,0.75,0.64,respectively,indicating no stoichiometric homeostatic characteristic.There were significant positive correlations of C ∶N,C ∶P,and N ∶P ratios between bulk soil and soil microbial biomass.However,there was no significant relationship of C ∶N,C ∶P,and N ∶P ratios between soil organic matter and soil microbial biomass.Our results indicated that change in soil carbon,nitrogen,and phosphorus can directly affect the stoichiometric ratio in soil microbial biomass.The stoichiometric ratio of soil organic matter might be influenced by cropping and nutrients management practices,other than the stoichiometric ratio in soil microbial biomass.关键词
化学计量学/长期施肥/黑土/土壤有机质/微生物生物量/内稳性Key words
stoichiometry/long-term fertilization/black soil/soil organic matter/microbial biomass/homeostasis引用本文复制引用
王传杰,王齐齐,徐虎,高洪军,朱平,徐明岗,张文菊..长期施肥下农田土壤-有机质-微生物的碳氮磷化学计量学特征[J].生态学报,2018,38(11):3848-3858,11.基金项目
国家自然科学基金项目(41371247) （41371247）
中国农业科学院创新工程协同创新行动(CAAS-XTCX2016008) （CAAS-XTCX2016008）
国家公益性行业(农业)科研专项(201303126) （农业）
