摘要
【目的】气候变化对人类社会发展产生的影响受到了世界各国的广泛关注,提高森林生态系统的固碳潜力被认为是经济可行且有效减缓大气二氧化碳(CO2)浓度的重要途径之一,大兴安岭地区森林生态系统的黑碳储量在全球碳循环和碳汇方面具有重要的作用。研究大兴安岭不同地形因子条件下土壤黑碳的储藏分布特征,为区域森林土壤黑碳储量准确估算和森林土壤固碳功能的定量评估提供参考依据。【方法】在大兴安岭北端寒温带针叶林区,按照坡位、坡向差异,对称设置20块样地,采集1 m剖面内不同发生层土样。采用氢氟酸(HF)和盐酸(HCl)处理的重铬酸盐氧化方法对土壤黑碳进行分离,探讨了地形因子(坡位、坡向和坡度)对黑碳(BC)分布的影响,并借助逐步回归分析量化各因子对土壤黑碳密度变异的相对影响程度。【结果】①研究区土壤黑碳密度(面密度)范围为0.02~3.64 kg/m2,腐殖质层密度最大,占全剖面的50.3%,具有明显的表层集聚效应;黑碳占有机碳的比例范围为3.7%~42.5%,除凋落物层外随深度增加呈不断增加的趋势,说明黑碳含量依土层减小的程度比有机碳含量依土层减少的程度小,对比非黑碳成分黑碳向下迁移的程度更大,其稳定性更强;各土层黑碳含量变化范围为0.24~59.13 g/kg,空间变异性较大。②坡位显著影响土壤黑碳含量和密度的分布,不同土层之间下坡位的黑碳含量均显示高于上坡位,下坡腐殖质层黑碳密度是上坡的2.21倍,其1 m剖面黑碳密度是上坡的1.91倍;不同土层间黑碳占有机碳比例均显示下坡位高于上坡位,而差异未达到显著水平;逐步回归显示,坡位对土壤黑碳数量分异的影响较大,可独立解释腐殖质层黑碳密度空间变异的42.1%、1 m剖面黑碳密度空间变异的46.0%。③坡向通过光照和温度的不同影响黑碳储量分布,总体看来,BC含量(除凋落物层和母质层)和
【Objective】The impact of climate change on the development of human society has attracted extensive attention all over the world.Improving the carbon sequestration potential of forest ecosystems is considered to be one of the important ways to reduce atmospheric CO2 concentration economically and effectively.The black carbon(BC)reserves of forest ecosystems in the Greater Khingan Mountains area play an important role in the global carbon cycle and carbon sequestration.The storage and distribution characteristics of soil BC under different topographical factors were studied in order to provide basic parameters for the accurate estimation of BC storage in regional forest soil and for the quantitative evaluation of forest soil carbon sequestration.【Method】Based on differences in slope positions and slope aspects,20 sample plots were set up symmetrically in the cold temperate conifer forest area at the northern end of the Greater Khingan Mountains,and soil samples from different occurrence layers in 1 m sections were collected.Soil BC was separated by the oxidation of dichromate treated with HF/HCl.The effects of topographical factors(the position,aspect and gradient of slope)on the distribution of soil BC were investigated.The relative influence of each factor on the variation in soil BC density was quantified by the stepwise regression analysis.【Result】①The soil BC density in this area ranges from 0.02 to 3.64 kg/m2.The density of the humus layer was the highest,accounting for 50.3%of the total,which had an obvious surface agglomeration effect.The BC contributions ranged from 3.7%to 42.5%of the organic carbon.With increasing depth,there was an increasing trend(except for the litter layer).The results showed that the degree of decrease of the BC content in the soil layer was smaller than that of the organic carbon content,according to the soil layer.Compared with the non-BC composition,the downward migration of BC was greater,and its stability was stronger.The variation range of the BC content in each
作者
王明哲
崔晓阳
李斯雯
张伟波
赵华晨
WANG Mingzhe;CUI Xiaoyang;LI Siwen;ZHANG Weibo;ZHAO Huachen(School of Forestry,Northeast Forestry University,Harbin 150040,China)
出处
《南京林业大学学报（自然科学版）》
CAS
CSCD
北大核心
2021年第1期151-158,共8页
Journal of Nanjing Forestry University：Natural Sciences Edition
基金
国家重点研发计划(2016YFA0600803)
国家自然科学基金项目(41330530)。
关键词
针叶林
土壤黑碳
有机碳
地形因子
空间变异
大兴安岭
coniferous forest
soil black carbon
organic carbon
topography factor
spatial variability
Greater Khingan Mountains
