林火干扰后大兴安岭多年冻土区土壤胞外酶活性变化特征及其影响因素  

Post-fire changes in soil extracellular enzyme activities and their influencing factors in the permafrost region of the Da Xing'anling Mountains, Northeast China

作　　者：沈阳 李晓英 蔡慧颖[1] 许涛 李景涛 陈魁 SHEN Yang;LI Xiaoying;CAI Huiying;XU Tao;LI Jingtao;CHEN Kui(Key Laboratory of Sustainable Forest Ecosystem Management of Ministry of Education,College of Forestry,Northeast Forestry University,Harbin 150040,China;State Key Laboratory of Cryospheric Science and Frozen Soil Engineering,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China)

机构地区：[1]东北林业大学林学院森林生态系统可持续经营教育部重点实验室,哈尔滨150040 [2]中国科学院西北生态环境资源研究院冰冻圈科学与冻土工程全国重点实验室,兰州730000

出　　处：《应用生态学报》2025年第2期497-503,共7页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(42471166,32241032);冰冻圈科学与冻土工程全国重点实验室自主部署项目(CSFSE-ZQ-2407);黑龙江省优秀青年基金项目(YQ2022D002)资助。

摘　　要：探究火后多年冻土区土壤酶活性的变化特征及其影响因素有助于预测和评估气候变暖对多年冻土区生态系统的影响。本研究选取大兴安岭北部多年冻土区2015年火烧迹地分析未火烧、轻度火烧、重度火烧区0~60 cm深度土壤中的脲酶(UR)、酸性磷酸酶(AP)、乙酰基葡萄糖苷酶(NAG)、β-葡萄糖苷酶(βG)和亮氨酸氨基肽酶(LAP)等胞外酶活性变化特征及其影响因素。结果表明:火烧强度、土壤深度和土壤理化性质对土壤胞外酶活性均有显著影响。与未火烧点相比,轻度火烧点土壤的UR、AP、βG和LAP活性升高了59.8%~241.7%,NAG活性降低了35.5%;重度火烧点所有土壤酶活性均升高,增幅为26.0%~206.0%。随土壤深度增加,土壤酶活性逐渐降低。冗余分析表明,土壤温度(ST)、全磷(TP)、C∶P、C∶N、土壤深度和土壤含水量(SWC)是土壤酶活性的重要影响因子,贡献率分别为70.9%、12.2%、4.7%、3.6%、2.9%和1.9%;土壤酶活性与ST、TP、C∶P、C∶N和SWC呈显著正相关,与土壤深度呈显著负相关。林火及其诱发的土壤理化性质变化共同影响土壤胞外酶活性,且火烧强度越大影响越显著。Understanding the changes in soil enzyme activities and the influencing factors after forest fire distur-bances can help assess and predict the impacts of climate warming on permafrost ecosystems. We analyzed the acti-vities of extracellular enzyme, including urease(UR), acid phosphatase(AP), acetyl-glucosidase(NAG), β-glucosidase(βG), and leucine aminopeptidase(LAP), in soils(0-60 cm depth) across unburned, lightly burned and severely burned sites within the 2015 burned area in the northern Da Xing'anling Monntains. The results showed that fire intensity, soil depth, and soil physicochemical properties significantly influenced extracellular enzyme activities. Compared to that in unburned site, the activities of UR, AP, βG, and LAP increased by 59.8%-241.7%, while NAG decreased by 35.5% at lightly burned site. The activities of all soil enzymes increased, with the magnitidues ranging from 26.0% to 206.0% at severely burned site. Soil enzyme activities gra-dually decreased with increasing soil depth. Redundancy analysis identified soil temperature(ST), total phosphorus(TP), C:P, C:N, soil depth and soil water content(SWC) as important influencing factors of soil enzyme activities, contributing 70.9%, 12.2%, 4.7%, 3.6%, 2.9%, and 1.9%, respectively. Soil enzyme activities were signifi-cantly positively correlated with ST, TP, C:P, C:N, and SWC, but significantly negatively correlated with soil depth. Forest fires and the resultant changes in soil physicochemical properties jointly affected soil extracellular enzyme activities, with the effects intensifying with increasing fire intensity.

关 键 词：林火 多年冻土 大兴安岭 土壤胞外酶活性 火烧强度 

分 类 号：S714.3[农业科学—林学]