摘要
以亚热带天然阔叶林和由其转换而来的针阔混交人工林和杉木人工林为研究对象,探讨森林转换对土壤有机碳(Soilorganiccarbon,SOC)含量和分布格局的影响。选取不同土层(0~20cm、20~40cm、40~60cm)土壤作为样本,运用物理分组方法研究森林转换对土壤粗颗粒有机碳(Coarse particulate organic carbon,CPOC)、细颗粒有机碳(Fine particulate organic carbon,FPOC)、矿物结合态有机碳(Mineral-associatedorganiccarbon,MOC)含量及其分配比例的影响。结果表明:天然林转换为人工林后(1)各土层土壤有机碳含量均呈下降趋势;(2)0~20cm土层土壤粗颗粒有机碳含量和分配比例均显著降低,土壤细颗粒有机碳含量和比例呈增加趋势;矿物结合态有机碳含量呈减少趋势,比例呈增加趋势;(3)各土层土壤颗粒有机碳/矿物结合态有机碳(POC/MOC)和矿物结合态有机碳/土壤有机碳(MOC/SOC)比值均呈下降趋势,0~20 cm土层土壤CPOC与SOC相关性最好,40~60cm土层MOC与SOC相关性最好。因此,亚热带天然阔叶林转换为针阔混交人工林和杉木人工林,土壤总有机碳含量降低,土壤有机碳的稳定性增强;土壤CPOC更能反映森林转换对表层土壤有机碳的影响;而MOC更能反映森林转换对深层土壤有机碳的影响。
【Objective】Any changes, even minor ones, in forest soil carbon pool would have profound effects on atmospheric CO2 concentration and global climate change. Particulate organic carbon is mainly of semi-decomposed plant residues and very high in biological activity and short in turnover cycle, so it can be used as an indicator of changes in soil organic carbon. Change in forest type or forest conversion is an important pattern of changes in land use, and affects storage and transformation of soil organic carbon through increasing or reducing biomass of the plants and litter on the ground. So, it is an important driving force of soil organic carbon(SOC) dynamics. This paper focused on conversion of natural broad-leaved forest to mixed coniferous-broad-leaved forest or Chinese fir plantations(Cunninghamia lanceolata [Lamb.]Hook) in subtropical China to explore effects of the conversion on content of SOC and its distribution in the forestland. Therefore, three tracts of forests were selected as subjects of the study, i.e., a 28-years-old natural broad-leaved forest, a Chinese fir plantation and an artificial mixed coniferous broad-leaved forest converted from natural broad-leaved forest in November 2016. 【Method】Soil samples were collected from different soil layers(0~20 cm, 20~40 cm, and 40~60 cm) in the forestlands for analysis of effects of the conversion on contents of soil coarse particulate organic carbon(CPOC), soil fine particulate organic carbon(FPOC), and mineral-associated organic carbon(MOC) and their ratio.【Result】Results show that once natural forest was converted into artificial ones,(1) content of soil organic carbon in various soil layers and stock of litter on the surface decreased significantly;(2) CPOC decreased in content by 60.0% and 54.6% in the mixed coniferous broad-leaved forest and Chinese fir plantation, respectively and in proportion, too in the 0~20 cm soil layer, while FPOC did reversely in both content and proportion; however, MOC declined in content, but rose in proportion,
作者
胡雪寒
刘娟
姜培坤
周国模
李永夫
吴家森
HuXuehan;LIUJuan;JIANGPeikun;ZHOUGuomo;LIYongfu;WUJiasen(State Key Laboratory of Subtropical Silviculture,Zhejiang A&F University,Lin'an,Zhejiang 311300,China;Zhejiang Provincial Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration,Zhejiang A&F University,Lin'an,Zhejiang 311300,China)
出处
《土壤学报》
CAS
CSCD
北大核心
2018年第6期1485-1493,共9页
Acta Pedologica Sinica
基金
国家自然科学基金项目(31700540)
浙江省自然科学基金项目(LY15C160004)资助~~
关键词
林分转换
颗粒态有机碳
土壤粒径
天然林
人工林
Forest conversion
Particulate organic carbon
Particle size of soil
Natural forest
Plantations