不同植被覆盖方式对土壤活性有机碳及腐殖质的影响  

Effect of different vegetation cover types on soil active organic carbon and humus

作　　者：杨满元[1] 李娟 杨宁[1] 刘慧娟 黄雯 魏甲彬 梁忠厚 YANG Manyuan;LI Juan;YANG Ning;LIU Huijuan;HUANG Wen;WEI Jiabin;LIANG Zhonghou(College of Landscape Architecture,Hunan Environmental-Biological Polytechnic College,Hengyang,Hunan 421005,China)

机构地区：[1]湖南环境生物职业技术学院园林学院,湖南衡阳421005

出　　处：《西北农林科技大学学报（自然科学版）》2023年第9期92-100,共9页Journal of Northwest A&F University(Natural Science Edition)

基　　金：湖南省科技厅项目(S2006N332);湖南省自然科学基金项目(2018JJ5027);衡阳市科技计划项目(202150083609);湖南环境生物职业技术学院南岳学者基金项目(N2021-03)。

摘　　要：【目的】探讨不同植被覆盖方式对土壤有机碳和腐殖质组分的影响,为湖南衡阳不同植被恢复措施的生态效益评价提供依据。【方法】以研究区不同植被覆盖模式(自然恢复草地、人工恢复草地、灌丛草本混交地、灌丛地和乔木灌丛混交地)土壤作为研究对象,分析表层(0~10 cm)与亚表层(10~20 cm)土壤理化性质、土壤活性有机碳组分和土壤腐殖质组分的特征。【结果】①自然恢复草地土壤pH显著高于其他植被覆盖方式,自然恢复草地和灌丛地土壤体积质量显著高于其他植被覆盖方式,土壤有机碳、碱解氮和速效磷含量则以人工恢复草地和灌丛草本混交地显著高于其他植被覆盖方式,速效钾含量在不同植被覆盖方式间差异不显著。②人工恢复草地与灌丛草本混交地的土壤微生物生物量碳、胡敏酸、富里酸、胡敏素含量及胡敏酸/土壤有机碳、胡敏酸/富里酸显著高于其他植被覆盖方式(P<0.05)。③人工恢复草地与灌丛草本混交地的土壤易氧化有机碳、土壤微生物熵与土壤有机碳活度显著低于其他植被覆盖方式(P<0.05)。④除速效钾外,土壤微生物生物量碳、土壤易氧化有机碳、土壤微生物熵和土壤有机碳活度均与土壤腐殖质组分以及土壤理化性质存在密切的相关性。【结论】人工恢复草地与灌丛草本混交地的土壤有机碳稳定性较强,土壤腐殖化度和腐殖质聚合度更高,更有利于土壤碳的积累与土壤肥力的提高。【Objective】This study explored the influence of different vegetation cover types on soil organic carbon(SOC)and humus compositions to provide basis for evaluating ecological benefits of different vegetation restoration measures in Hengyang.【Method】The study focused on surface(0-10 cm)and subsurface(10-20 cm)soil samples under different vegetation cover types including natural restoration grassland(NRG),restoration of artificial grassland(RAG),shrub-herb mixed land(SHML),shrub land(SL)and mixed land of trees and shrubs(MLTS)in Hengyang,China.Soil physico-chemical properties,fractions of soil active organic carbon(SAOC)including soil microbial biomass carbon(SMBC),soil easily oxidizable organic carbon (SEOC) and composition of soil humic substance (SHS) including humic acid (HA),fulvic acid (FA) and humin (HM) were analyzed.【Result】 ① Soil pH in NRG was significantly higher than other vegetation cover types (P <0.05),soil bulk density (SBD) in NRG and SL were signifi-cantly higher than other three vegetation cover types (P <0.05),contents of SOC,alkali-hydrolyzable ni-trogen (AN) and available phosphorus (AP) in RAG and SHML were significantly higher than other vege-tation cover types(P <0.05),while there was no significant difference in available potassium (AK) among vegetation cover types (P >0.05).② Contents of SMBC,HA,FA and HM and ratios of HA/SOC and HA/FA in RAG and SHML were significantly higher than other three vegetation cover types (P <0.05). ③ SEOC content,qMB(SMBC/SOC) and SOCA [SEOC/(SOC-SEOC)] in RAG and SHML were signifi-cantly lower than other three vegetation cover types (P <0.05).④ SMBC,SEOC,qMB and SOCA were closely related to SHS composition and soil physico-chemical properties apart from AK.【Conclusion】 RAG (Melilotus albus-Crotalaria pallid) and SHML(Amorpha fruticosa +Melilotus albus) with stronger SOC stabilization and higher soil humification degree and humus polymerization were most beneficial to soil carbon accumulation and fertility improvement.

关 键 词：植被覆盖方式 土壤有机碳 植被恢复 腐殖化度 紫色土 

分 类 号：S153.62[农业科学—土壤学]