摘要
北方针叶林长期受到不同程度的林火干扰,这对于森林土壤养分循环起到关键作用。为探究不同立地条件下林火发生后的土壤养分特征,以大兴安岭呼中地区火烧迹地土壤为研究对象,选取林龄、坡位相近和立地条件不同的4块样地采集土样,测定并分析火烧迹地不同区域(核心区、边缘区和未过火林分)土壤pH、全碳(Total carbon,TC)、全氮(Total nitrogen,TN)、全磷(Total phosphorus,TP)和有机碳(Soil organic carbon,SOC)等主要化学性质以及2种土壤酶活性(纤维素酶(CBH)、β-葡萄糖苷酶(βG))。结果表明,落叶松-白桦混交林土壤养分条件最为丰富,且火后土壤养分含量仍优于其余3组样地。相较于未过火区,各林型边缘区TC和SOC含量显著降低,土壤水解酶CBH、βG活性总体呈显著上升的趋势(P<0.05)。而相较于边缘区,以落叶松为主的落叶松-偃松混交林核心区TC、TN和SOC显著降低(P<0.05),落叶松-白桦混交林核心区土壤TC、TN和SOC含量显著升高(P<0.05),核心区土壤CBH和βG活性相较于边缘区主要呈显著下降趋势,而落叶松-白桦混交林核心区酶活性相较于边缘区显著回升(P<0.05)。火干扰对各林型土壤pH均未造成显著影响(P>0.05)。判别分析表明,以过火区域为因变量比以林型为因变量建立的判别函数整体区分度差。综上所述,林火可以显著影响当地4种林型(以偃松为主的落叶松-偃松混交林、以落叶松为主的落叶松-偃松混交林、塔头-落叶松林、落叶松-白桦混交林)中土壤主要养分含量及相关土壤酶活性,而对土壤pH影响较小,林型间的土壤养分差异大于不同火烧区域土壤养分差异,在火后恢复初期应结合火烧迹地养分情况及立地条件分别施策人工促进恢复。该研究可为评估火干扰对寒温带兴安落叶松林土壤养分变化的影响提供理论支撑,为北方针叶林火后恢复营林方案的制定提供参考。
The Boreal forest has been disturbed by forest fire in different degrees for a long time,which plays a key role in nutrient cycling in forest soil.In order to explore the soil nutrient characteristics after forest fire under different site conditions,the soil of burned area in Huzhong forestry bureau of Greater Khingan Mountains was selected as the research object,soil samples were collected from four plots with similar forest age,slope location and different site conditions.Main chemical properties of soil pH,soil total carbon(TC),soil total nitrogen(TN),soil total phosphorus(TP),soil organic carbon(SOC)as well as two soil enzyme activities(cellulase(CBH)andβ-glucosidase(βG))in different areas(interior area,edge area,and unburned area)were measured and analyzed.The result showed that the Larix gmelinii-Betula platyphylla mixed forest had the most abundant soil nutrient conditions,and the soil nutrient content after a fire was still better than the other three sample sites.Compared to the unburned area,TC and SOC in the edge area of each forest type decreased significantly,the activity of soil enzyme CBH andβG showed a significant upward trend(P<0.05).Compared with the edge area,TC,TN and SOC were significantly decreased(P<0.05)in the interior area of Larix gmelinii-Pinus pumila forest mixed forest dominated by Larix gmelinii,while the contents of TC,TN and SOC were significantly increased(P<0.05)in the Larix gmelinii-Betula platyphylla mixed forest,and the activities of CBH andβG in the interior area were significantly decreased compared with the edge area,while the enzyme activity in the interior area of the Larix gmelinii-Betula platyphylla mixed forest was significantly higher than that in the edge area(P<0.05).Fire disturbance had no significant effect on soil pH in these forest types(P>0.05).Fisher discriminant analysis showed that the overall differentiation of sample distribution was worse when the burned area was taken as the dependent variable than when Pinus pumila-Larix gmelinii forest mixed fores
作者
郑鑫
丛日征
王剑南
张吉利
ZHENG Xin;CONG Rizheng;WANG Jiannan;ZHANG Jili(Research Center of Cold Temperate Forestry,Chinese Academy of Forestry,Harbin 150086,China)
出处
《森林工程》
北大核心
2023年第5期74-84,共11页
Forest Engineering
基金
中国林业科学研究院中央级公益性科研院所基本科研业务费专项资金(CAFYBB2019MA007)。
关键词
兴安落叶松
林火
土壤养分
土壤酶活性
森林类型
Larix gmelinii
forest fire
soil nutrient
soil enzyme activity
forest type
