滨海滩涂不同土地利用类型土壤活性有机碳含量与垂直分布  

Content and vertical distribution of soil labile organic carbons in different land use types in the tidal flat area

作　　者：许梦璐 吴炜 颜铮明 曹国华 沈彩芹 阮宏华 XU Menglu;WU Wei;YAN Zhengming;CAO Guohua;SHEN Caiqin;RUAN Honghua(Co-Innovation Center for the Sustainable Forestry in Southem China,College of Biology and the Environment,Nanjing Forestry University,Nanjing 210037,China;DongtaiCity Forest Farm of Jiangsu Province,Dongtai 224200,China)

机构地区：[1]南京林业大学生物与环境学院,南方现代林业协同创新中心,江苏南京210037 [2]江苏省东台市林场,江苏东台224200

出　　处：《南京林业大学学报（自然科学版）》2020年第4期167-175,共9页Journal of Nanjing Forestry University：Natural Sciences Edition

基　　金：国家重点研发计划(2016YFD0600204);江苏高校优势学科建设工程资助项目(PAPD)。

摘　　要：【目的】近年来,滨海滩涂已成为人类围垦开发的主要区域。围垦,一方面改变了土壤基本的理化性质,另一方面也加速了土壤有机碳库的变化,特别是对围垦活动比较敏感的活性有机碳,因此研究围垦区不同土地利用类型下土壤有机碳及其活性组分的含量与差异,能够为合理开发利用滨海湿地,了解围垦区的土壤碳循环特征提供参考。【方法】选择江苏东台沿海滩涂围垦区林地、旱地及水田土壤作为研究对象,并以光滩土壤作为对照,分层采集不同剖面的土壤样品,分析不同土地利用类型下可溶性有机碳(dissolved organic carbon,DOC)、微生物生物量碳(microbial biomass carbon,MBC)和易氧化碳(easily oxidized carbon,EOC)含量的变化特征及与土壤基本理化指标间的相关性。【结果】①随着土层深度的增加,各土地利用类型土壤DOC含量呈先增(0~40 cm)后减(≥40~100 cm)的趋势;土壤MBC和EOC含量均随土层深度呈现显著阶梯式下降。不同土地利用类型同一土层,除了DOC含量表现为光滩显著大于林地、旱地和水田外,MBC和EOC的含量由大到小顺序依次为林地、水田、旱地、光滩。②随土层深度的增加,DOC和MBC分配比例的变化趋势一致,即光滩中无明显变化规律,林地、旱地和水田均先增后减,EOC分配比例随着土层深度的增加则没有表现出一致的变化趋势。0~40 cm土层,林地、旱地和水田的有机碳活性组分分配比例均显著低于光滩,40cm以下,各分配比例没有呈现一致的规律。③土壤MBC和EOC含量之间存在极显著相关关系,且二者均与土壤总有机碳(soil organic carbon,SOC)、总氮(total nitrogen,TN)含量呈极显著正相关,与p H呈极显著负相关,但与电导率(electric conductivity,EC)和总磷(total phosphorus,TP)含量之间不存在相关关系。而土壤DOC含量则与各指标间均不存在相关性。【结论】人为的农业耕种措施显著增加了土壤有�【Objective】Coastal tidal flats have a high carbon sequestration potential,which may contribute to alleviating the global greenhouse effect.However,they are being reclaimed at an increasing rate because they provide important land for relieving population pressure,promoting regional economic growth,and ensuring food safety.With the largest area of tidal flats in China,a long history of coastal reclamation activities has been existed in Jiangsu Province.Tidal flat reclamation practices change the basic physical and chemical properties of soil,and accelerate changes in the soil organic carbon pool,especially the active organic carbon,which is sensitive to reclamation activities.Meanwhile,the active organic carbon components can be used to characterize the short term changes in the soil organic carbon pool.As such,studying the differences in soil organic carbon and its active components under different land use types in reclamation areas may provide a reference for the rational development and utilization of coastal wetlands.It is also important to elucidate the role of soil carbon in coastal reclamation areas.【Method】A bare tidal flat,paddy field,and area of upland and forest land in the reclamation area in Dongtai,Jiangsu were selected as research sites.At each site,soil samples were collected from different soil depth layers in order to analyze the variations in dissolved organic carbon(DOC),microbial biomass carbon(MBC)and easily oxidized carbon(EOC)under the different land use types.【Result】①With the increase of soil depth,the DOC content increased in soil depths of 0—40 cm soils,but decreased in soil depths of 40—100 cm.Furthermore,the MBC and EOC content decreased significantly in soil depths of 0—100 cm across the four land use types.When tested in the same soil layer,the DOC content of the bared tidal flat soil was significantly larger than that of the soil in the other three land use types.However,the MBC and EOC content descended in the following order:forest land,paddy field,upland,bar

关 键 词：可溶性有机碳 微生物生物量碳 易氧化碳 土地利用类型 滩涂围垦 

分 类 号：S154.1[农业科学—土壤学] S714[农业科学—农业基础科学]