长期施用沼液对杨树人工林土壤碳氮磷及其计量比的影响  

Effects of long-term application of biogas slurry on soil carbon,nitrogen,phosphorus and their metering ratio in poplar plantations

作　　者：张苗[1] 阮宏华[1] 沈彩芹 丁学农 曹国华 ZHANG Miao;RUAN Honghua;SHEN Caiqin;DING Xuenong;CAO Guohua(College of Ecology and Environment,Co-Innovation Center for Sustainable Forestry in Southern China,Nanjing Forestry University,Nanjing 210037,China;Dongtai State Forest Farm,Dongtai 224237,China)

机构地区：[1]南京林业大学生态与环境学院,南方现代林业协同创新中心,江苏南京210037 [2]江苏省东台市林场,江苏东台224237

出　　处：《南京林业大学学报(自然科学版)》2024年第6期102-110,共9页Journal of Nanjing Forestry University:Natural Sciences Edition

基　　金：国家重点研发计划(2021YFD02200403);江苏省林业局“揭榜挂帅”项目(LYKJ【2022】01);江苏省林业局造林专项【2021-2022】

摘　　要：【目的】探讨长期施用不同浓度沼液对杨树(Populus spp.)人工林土壤碳、氮、磷组分含量的影响,为科学施用沼液,改善杨树人工林土壤质量,促进杨树人工林可持续发展提供理论依据。【方法】以苏北沿海地区杨树人工林为研究对象,试验采用随机区组设计,设置了4种沼液施用处理,分别为对照(0 m^(3)/hm^(2),CK)、低浓度(125 m^(3)/hm^(2),L)、中浓度(250 m^(3)/hm^(2),M)和高浓度(375 m^(3)/hm^(2),H),自2012年开始每年定期在杨树人工林中施用。采用连续土钻法采集不同土壤深度0~20 cm(表层),≥20~40 cm(中层)和≥40~60 cm(深层)土壤样品,研究施用不同浓度沼液对杨树人工林不同土层土壤碳、氮、磷主要组分含量及其计量比的影响。【结果】施用沼液显著增加了表层土壤(0~20 cm)有机碳(SOC)、可溶性有机碳(DOC)、土壤微生物生物量碳(MBC)、土壤总氮(TN)、土壤微生物生物量氮(MBN)、土壤全磷(TP)、土壤有效磷(AP)含量,显著降低了表层土壤碳氮质量比(C/N)和土壤微生物生物量碳氮比(MBC/MBN);同时施加沼液也显著增加了≥20~40 cm土层土壤DOC、TP含量。而在深层土壤(≥40~60 cm)中,施加沼液对土壤C、N、P各项指标均无显著影响。沼液显著降低了各土层土壤pH。【结论】沼液作为一种优质的速效有机肥料,能显著增加表层土壤C、N、P等速效养分,对深层土壤无显著影响。同时,施用适量沼液也可以降低沿海盐碱地土壤pH,以及土壤C/N,对改善土壤肥力有一定的作用,但过度施加是否会引起土壤磷素淋洗、氮淋溶风险而造成生态环境污染还有待进一步研究。【Objective】The effects of biogas slurry on soil carbon(C),nitrogen(N),and phosphorus(P)contents were studied in poplar plantations in coastal areas of northern Jiangsu,China.This research aims to provide a theoretical basis for the scientific utilization of biogas slurry,the optimization of fertilization technology,and the promotion of sustainable development in poplar plantations.【Method】The experiment employed a randomized block design with four levels of biogas slurry application:CK(0 m^(3)/hm^(2)),L(125 m^(3)/hm^(2)),M(250 m^(3)/hm^(2))and H(375 m^(3)/hm^(2)).Soil samples were collected from different depths:0-20 cm(surface layer),≥20-40 cm(middle layer),and≥40-60 cm(deep layer)using a continuous soil coring method.The study examined the effects of various biogas slurry concentrations on soil C,N and P contents across different soil layers and growing seasons in the poplar plantations.【Result】Biogas slurry application significantly increased the soil organic carbon(SOC),dissolved organic carbon(DOC),microbial biomass carbon(MBC),microbial biomass nitrogen(MBN),total phosphorus(TP),and available phosphorus(AP)in the topsoil(0-20 cm).It also significantly decreased the C/N ratio(mass fraction ratio,the same below)and MBC/MBN ratio in the topsoil.Additionally,biogas slurry significantly increased DOC and TP in the≥20-40 cm soil layer.However,in the deep soil(≥40-60 cm),biogas slurry had no significant effect on soil C,N,and P levels.Biogas slurry application also significantly reduced soil pH across all layers.【Conclusion】Our research indicates that biogas slurry,as a high-quality,quick-acting organic fertilizer,significantly increases nutrients such as C,N,and P in surface soil but does not affect deep soil.It also reduces soil pH and C/N ratio in coastal saline-alkali soil,improving soil fertility.However,further research is needed to determine whether excessive application could risk phosphorus and nitrogen leaching and potential ecological pollution.

关 键 词：杨树人工林 沼液 土壤碳、氮、磷 土壤微生物生物量 土壤碳氮比 土壤微生物生物量碳氮比 

分 类 号：S714.2[农业科学—林学]