河北平泉油松林火烧迹地土壤氮变化特征  

Characteristics of soil nitrogen change in the burned area of Pinus tabuliformis forest in Pingquan County,Hebei Province of northern China

作　　者：李炳怡 刘冠宏 顾泽 李伟克 田野[2] 王博[2] 刘晓东[2] 舒立福[1] Li Bingyi;Liu Guanhong;Gu Ze;Li Weike;Tian Ye;Wang Bo;Liu Xiaodong;Shu Lifu(Key Laboratory of Forest Protection of National Forestry and Grassland Administration,Ecology and Nature Conservation Institute,Chinese Academy of Forestry,Beijing 100091,China;School of Ecology and Nature Reserves,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]中国林业科学研究院森林生态环境与自然保护研究所,国家林业和草原局森林保护学重点实验室,北京100091 [2]北京林业大学生态与自然保护学院,北京100083

出　　处：《北京林业大学学报》2023年第3期1-10,共10页Journal of Beijing Forestry University

基　　金：国家重点研发计划重点专项的子课题(2020YFC1511601)。

摘　　要：【目的】分析河北省平泉县火烧迹地油松天然次生林的土壤氮在火后不同年份的变化特征,结合林分因子、立地因子和可燃物因子,研究土壤氮变化的影响因素,为火烧迹地养分循环研究及恢复提供科学依据。【方法】选取河北平泉县柳溪镇油松林火烧迹地为研究对象,分别于2015年(火后当年)、2016年(火后1年)、2021年(火后6年)采集土壤样品,测定土壤全氮(TN)、碱解氮(AN)、铵态氮(NH_(4)^(+)-N)和硝态氮(NO_(3)^(-)-N)含量,比较和分析上述4种氮含量在不同火强度(轻度火烧、中度火烧、重度火烧、对照样地)、不同土层深度(0~10 cm和10~20 cm)在不同年份(2015、2016、2021年)的变化趋势。使用相关性分析和冗余分析探究林分因子(树高、胸径、郁闭度)、立地因子(坡度、坡向)和可燃物因子(1、10、100时滞可燃物载量、1、10、100时滞可燃物含水率)对土壤氮元素的影响。【结果】(1)整体而言,火强度、土层深度、年份对4种土壤氮含量具有显著影响(P<0.05),火强度和土层深度对2015年的4种土壤氮含量存在交互作用(P<0.05),火强度和年份对4种土壤氮含量存在交互作用(P<0.05),火强度、土层深度和年份对土壤氮含量不具有三因素交互影响(P>0.05);(2)火后1年(2016)土壤全氮、铵态氮、硝态氮含量回升,以重度火烧样地最为明显,增幅分别为464.67%、397.97%、185.63%,碱解氮含量降低,中度样地降幅为52.48%。火后6年(2021)土壤全氮、铵态氮、碱解氮含量在中度样地回升明显,增幅分别为368.78%、209.00%、427.51%,硝态氮含量在中、低强度下降,降幅为14.31%、14.34%;(3)RDA结果表明,可燃物含水率对土壤氮含量的变化贡献最多解释度:1时滞可燃物含水率影响碱解氮含量,并与其成正比关系;100时滞可燃物含水率影响硝态氮含量,并与其呈正比关系。林分因子和立地因子对土壤氮含量变化解释度较小,主要是间接作用�[Objective]The variation characteristics of soil nitrogen of Pinus tabuliformis natural secondary forest in Pingquan County,Hebei Province of northern China were analyzed in different years after fire,and the influencing factors of soil nitrogen were explored in combination with stand factors,site factors and fue factors,so as to provide a scientific basis for nutrient circulation and vegetation restoration after fire[Method]Study sites were burnt areas located in Liuxi Town of Pingquan County.Soil samples were collected in 2015(the year after the fire,0 year),2016 (1 year after the fire,1 year) and 2021 (6 years after the fire,6 years),respectively.We analyzed the tendency of content of soil total nitrogen (TN),alkalihydrolysable nitrogen (AN),ammonium nitrogen (NH_4~+-N) and nitrate nitrogen (NO_3^(-)-N) under differen years (0 year,1 year and 6 years),different fire intensities (CK,control test plots which is unburnt area;L low intensity burnt area;M,moderate intensity burnt area;H,heavy intensity burnt area),and different soi layers (0-10 cm and 10-20 cm).Correlation analysis (Pearson) and redundancy analysis (RDA) were used to explore the potential impact of stand factors (tree height,DBH,canopy density),site factors (slope position and slope gradient) and fuel factors (1 h,10 h,100 h fuel load,1 h,10 h,100 h fuel water content) on soil nitrogen.[Result](1) Fire intensity,soil layer and years had significant influence on 4 types of soi nitrogen (P<0.05).Fire intensity and soil layer had an interaction with all kinds of soil nitrogen (P<0.05)in 2015.Fire intensity and years had an interaction with all kinds of soil nitrogen (P<0.05).Fire intensity soil layer and years showed no three-factor interaction with all kinds of soil nitrogen (P>0.05).(2) Tota nitrogen content,ammonium nitrogen content and nitrate nitrogen content increased in 2016 (1 year)especially in heavy intensity areas (H),and the amplification was 464.67%,397.97%,185.63%,respectively But alkali-hydrolysable nitrogen content decreased in each sa

关 键 词：土壤养分配置 土壤氮元素 火烧迹地恢复 油松林 

分 类 号：S791.254[农业科学—林木遗传育种]