林下植被管理对杨树人工林土壤性质及有机碳组成的影响  

Effects of understory vegetation management on soil properties and organic carbon composition in poplar plantations

作　　者：石尚 于水强[1,2] 喻曼曼 黄越 王国兵[1,2] SHI Shang;YU Shuiqiang;YU Manman;HUANG Yue;WANG Guobing(College of Ecology and Environment,Nanjing Forestry University,Nanjing,Jiangsu 210037,China;Co-Innovation Center for Sustainable Forestry in Southern China,Nanjing Forestry University,Nanjing,Jiangsu 210037,China)

机构地区：[1]南京林业大学生态与环境学院,江苏南京210037 [2]南京林业大学南方现代林业协同创新中心,江苏南京210037

出　　处：《森林与环境学报》2025年第3期254-263,共10页Journal of Forest and Environment

基　　金：科技部国家“十四五”重点研发计划项目“森林经营措施对南方杨树人工林碳储量及其组成的影响机制”(2021YFD220040203)。

摘　　要：为探明不同林下植被管理模式对杨树人工林土壤性质、有机碳组分的影响,并筛选出杨树人工林有效的林下植被管理模式,以多年生杨树人工林为研究对象,设置保留林下植被、清除林下植被、保留单一植物和种植固氮植物4种林下植被管理模式,采集0~20 cm表层土壤样品并测定土壤理化性质、水解酶活性、有机碳组分含量。结果表明:与保留林下植被相比,清除林下植被显著降低土壤含水量、铵态氮(NH_(4)^(+)-N)、硝态氮(NO_(3)^(-)-N)和微生物量氮(MBN)含量(P<0.05);种植固氮植物能使土壤表现出较高的NH_(4)^(+)-N和NO_(3)^(-)-N含量、较低的土壤含水量并显著提高土壤有效磷含量(P<0.05);保留单一植物可保持中等的土壤水分和养分含量,但MBN含量显著低于保留林下植被(P<0.05)。清除林下植被的土壤酶活性较低,β-1,4-葡聚糖苷酶(BG)活性显著低于种植固氮植物,β-N-乙酰氨基葡萄糖苷酶(NAG)+亮氨酸氨基肽酶(LAP)活性显著低于保留林下植被;保留单一植物和种植固氮植物均显著提高了酸性磷酸酶(AcP)活性(P<0.05)。与保留林下植被相比,种植固氮植物可显著提高土壤有机碳和易氧化有机碳含量(P<0.05),清除林下植被的土壤有机碳和微生物量碳(MBC)含量最低(P<0.05)。土壤有机碳组分与土壤含水量、pH值、NH_(4)^(+)-N、NO_(3)^(-)-N、MBN含量、BG、BX和AcP活性之间存在显著相关关系(P<0.05);BG和MBN是土壤有机碳组分变化的主要影响因子。综上所述,保留林下植被和种植固氮植物可以保持较高的土壤养分含量和酶活性,并提高土壤总有机碳含量,有利于提高土壤质量并增强土壤的固碳能力;清除林下植被则与之相反。This study aims to investigate the effects of different understory vegetation management models on the soil properties and organic carbon components and screen the effective understory vegetation management model of poplar plantations.The multi-year poplar plantations were treated with four understory vegetation management models:retaining understory vegetation,removing understory vegetation,retaining a single plant species,and planting nitrogen-fixing plants.The surface soil(0-20 cm)was collected for determination of soil physicochemical properties,hydrolase activities,and content of organic carbon components.The results indicated that compared with retaining understory vegetation,removing understory vegetation reduced the content of soil water content,ammonium nitrogen(NH_(4)^(+)-N),nitrate nitrogen(NO_(3)^(-)-N),and microbial biomass nitrogen(MBN,P<0.05).The model of planting nitrogen-fixing plants showed higher NH_(4)^(+)-N and NO_(3)^(-)-N content,lower soil water content,and increased available phosphorus content(P<0.05).Retaining a single plant species maintained moderate water and nutrient content,with MBN content lower than that under retaining understory vegetation(P<0.05).The model of removing understory vegetation showcased lower enzyme activities,withβ-1,4-glucosidase(BG)activity significantly lower than that under planting nitrogen-fixing plants andβ-N-acetylglucosaminidase(NAG)+leucine aminptidase(LAP)activity significantly lower than that under retaining understory vegetation.Retaining a single plant species and planting nitrogen-fixing plants increased the acid phosphatase(AcP)activity(P<0.05).Compared with retaining understory vegetation,planting nitrogen-fixing plants increased the content of soil organic carbon and easily oxidizable organic carbon(P<0.05),while removing understory vegetation had the lowest content of soil organic carbon and microbial biomass carbon(MBC,P<0.05).The soil organic carbon components were correlated with soil water content,pH value,content of NH_(4)^(+)-N,NO_(3)^(

关 键 词：杨树人工林 林下植被 土壤有机碳 酶活性 土壤质量 

分 类 号：S714.6[农业科学—林学]