土壤增温对杉木幼苗细根生长量及形态特征的影响  

Effects of soil warming on fine root growth and morphology of Chinese fir (Cunninghamia lanceolata) seedlings

作　　者：陈望远 熊德成[1,2] 史顺增 宋涛涛 蔡瑛莹 郭润泉 陈廷廷 郑欣[1,2] 陈光水 CHEN Wangyuan1,2, XIONG Decheng1,2, SHI Shunzeng1,2, SONG Taotao1,2, CAI Yingying1,2, GUORunquan 1,2, CHEN Tingting1,2, ZHENG Xin1,2, CHEN Gunagshui1,2(1. State Key Laboratory of Subtropical Mountain Ecology（ Funded by Ministry of Science and Technology and Fujian Province） , Fujian Normal University Fuzhou 350007, China; 2. School of Geographical Sciences, Fujian Normal University, Fuzhou 350007, China)

机构地区：[1]福建师范大学湿润亚热带山地生态国家重点实验室培育基地,福州350007 [2]福建师范大学地理研究所,福州350007

出　　处：《生态学报》2018年第15期5305-5314,共10页Acta Ecologica Sinica

基　　金：国家自然科学基金优秀青年基金项目(31422012);福建省杰出青年基金项目滚动资助项目(2014J07005);福建师范大学"大学生创新创业训练计划"(创新训练类)项目(201610394066)

摘　　要：为了揭示杉木人工林对全球变暖的地下响应,在福建省三明市陈大国有林场开展杉木(Cunninghamia lanceolata)幼苗土壤增温试验,采用内生长环法探讨增温实验开始后第2年(2015年1月、7月取样)和第3年(2016年1月、7月取样)杉木幼苗细根生长量和形态特征(比根长,SRL;比表面积,SRA;组织密度,RTD)的变化。结果表明:(1)随着苗木的生长,土壤增温对细根生长量的影响趋势是先抑制,再无显著影响,最后促进。(2)土壤增温对细根形态特征的影响在不同取样时间有差异:土壤增温对7月份(夏季)取样的细根SRL或SRA有显著促进作用,对1月份(冬季)取样的细根SRL、SRA均无显著影响。(3)土壤增温对第二、第三次取样的1—2 mm细根RTD有促进作用。表明土壤增温对杉木幼苗细根生长量的影响与苗木生长阶段有关;同时苗木可通过细根形态的调整(增大SRL和RTD)以适应土壤增温引起的土壤资源变化和环境胁迫,维持自身的生长。Currently, there is large quantity of research on the responses of fine roots to warming, but there are still some controversies. Fine root growth has a direct effect on fine root biomass, and thus affects the plants＇ abilities to acquire soil resources and resist environmental stresses such as drought. Fine root morphology is an important feature of root function, and directly affects the ability of fine roots to absorb and transport water and nutrients, yet how root growth and morphology respond to soil warming is not clearly understood. In the present study, a simulated soil warming experiment was carried out in the Chenda State-owned Forest Farm in Sanming City, Fujian Province, China, to investigate the effect on fine root growth and morphology of Chinese fir （ Cunninghamia lanceolata） seedlings. Both the soil warming treatment and the control （non-warming） had five replicated 2 × 2 plots, and four 1-year-old Chinese fir seedlings were planted in each plot before beginning of the experiment. Soil warming was accomplished with buried heating cable technology, and soil temperature was elevated to 5℃ above ambient. Other plants that naturally sprouted in the plots were removed at regular intervals. Fine roots were sampled at the second （in January and July 2015） and third （in January and July 2016） years of soil warming using the in-growth donut method. Root samples were scanned with an Epson scanner at 300 dpi, and root morphology, including specific root length （SRL）, specific root area （SRA）, and root tissue density （RTD）, was analyzed with WinRHIZO Pro2009b software. Fine root growth was measured by the fine root dry mass obtained from the in-growth donut every half-year. The results showed that： （1） with the growth of Chinese fir seedlings, the effect of soil warming on fine root growth was initially inhibited, then no significant effect, and finally promoted. （2） The soil warming effect on root morphological characteristics varied at different sampling times： s

关 键 词：土壤增温 细根 内生长环 细根生长量 细根形态 

分 类 号：S791.27[农业科学—林木遗传育种]