水土保持学报2026，Vol.40Issue(2)：242-252,11.DOI:10.13870/j.cnki.stbcxb.2026.02.015
滇中华山松林不同季节土壤微生物碳利用效率对氮沉降的响应
Soil Microbial Carbon Use Efficiency in Pinus armandii Forests in Central Yunnan Responds to Nitrogen Deposition in Different Seasons
摘要
Abstract
[Objective]This study aims to reveal the characteristics of soil nutrients,microbial biomass,enzyme activities,soil microbial carbon use efficiency(CUE),and their seasonal variations in Pinus armandii forests in central Yunnan under nitrogen deposition,as well as to explore the key influencing factors of CUE.[Methods]Taking the soil of Pinus armandii forests in central Yunnan as the research object,six nitrogen deposition treatments were set up:control CK[0 g/(m²·a)],N5[5 g/(m²·a)],N10[10 g/(m²·a)],N15[15 g/(m²·a)],N20[20 g/(m²·a)],and N25[25 g/(m²·a)].The effects of soil nutrients,microbial biomass,enzyme activities,and their ecological stoichiometric characteristics on microbial CUE were determined and analyzed.Combined with partial least squares path modeling(PLS-PM)analysis,the response mechanism of soil microbial CUE to nitrogen deposition was clarified.[Results]Under different seasons,soil nitrate nitrogen(NO3--N),soil organic carbon(SOC),microbial biomass carbon,nitrogen,and phosphorus(MBC,MBN,MBP),β-glucosidase(BG),β-N-acetylglucosaminidase(NAG),cellulase(CL),EEAC:P((BG+CL)/ACP),EEAC:N((BG+CL)/NAG),and soil microbial carbon use efficiency(CUE)all showed a trend of first increasing and then decreasing with the increase of nitrogen deposition concentration.Among them,under the N10 treatment,NO3--N,MBC,MBP,and CUE were significantly higher than those in CK,increasing by 204.77%,35.00%,22.85%,and 68.68%,respectively.Soil nutrients,microbial biomass,stoichiometric ratios,and CUE were generally higher in the rainy season than in the dry season.Mantel analysis showed that CUE was significantly positively correlated with MBC,MBN,CL,NAG,and EEAN:P(NAG/ACP)in both dry and rainy seasons.Random forest analysis revealed that MBP,NAG,CL,ammonium nitrogen(NH4+-N),and EEAN:P contributed more to CUE.PLS-PM path model identifies nitrogen deposition as a key factor affecting CUE.Nitrogen deposition indirectly promotes CUE by altering nutrient availability and microbial biomass.[Conclusion]The research findings can provide a theoretical basis for exploring the response mechanisms of CUE to nitrogen deposition across different seasons in the region.关键词
土壤微生物碳利用效率/微生物生物量/土壤酶活性/化学计量特征/华山松林Key words
soil microbial carbon use efficiency/microbial biomass/soil enzyme activity/stoichiometric characteristics/Pinus armandii forest分类
农业科技引用本文复制引用
梁小玲,张龙,王克勤,宋娅丽,舒海苑,周玉玺,张茜..滇中华山松林不同季节土壤微生物碳利用效率对氮沉降的响应[J].水土保持学报,2026,40(2):242-252,11.基金项目
云南省科技厅面上项目(202401AT070262) （202401AT070262）
云南省农业基础研究联合专项(202301BD070001-059) （202301BD070001-059）
