中亚热带植被恢复对土壤有机碳含量、碳密度的影响  

Effects of vegetation restoration on soil organic carbon concentration and density in the mid-subtropical region of China

作　　者：辜翔[1] 张仕吉[1] 刘兆丹 李雷达[1] 陈金磊 王留芳 方晰[1,2,3] GU Xiang;ZHANG Shi-Ji;LIU Zhao-Dan;LI Lei-Da;CHEN Jin-Lei;WANG Liu-Fang;FANG Xi(School of Life Science and Technology, Central South University of Forestry and Technology, Changsha 410004, China;National Engineering Laboratory of South China Forestry Ecology Applicable Technologies, Changsha 410004, China;Huitong National Field Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystem of Hunan Province, Huitong, Hunan 438107, China)

机构地区：[1]中南林业科技大学生命科学与技术学院,长沙410004 [2]南方林业生态应用技术国家工程实验室,长沙410004 [3]湖南会同杉木林生态系统国家野外科学观测研究站,湖南会同438107

出　　处：《植物生态学报》2018年第5期595-608,共14页Chinese Journal of Plant Ecology

基　　金：国家林业公益性行业科研专项(201504411);国家自然科学基金项目(30771720和31170426)~~

摘　　要：为揭示植被恢复对土壤有机碳(SOC)库的影响机制,采用空间代替时间的方法,以湘中丘陵区地域相邻、环境条件基本一致的檵木(Loropetalum chinense)-南烛(Vaccinium bracteatum)-杜鹃(Rhododendron simsii)灌草丛(LVR)、檵木-杉木(Cunninghamia lanceolata)-白栎(Quercus fabri)灌木林(LCQ)、马尾松(Pinus massoniana)-柯(又名石栎)(Lithocarpus glaber)-檵木针阔混交林(PLL)和柯-红淡比(Cleyera japonica)-青冈(Cyclobalanopsis glauca)常绿阔叶林(LAG)作为一个恢复演替序列,设置固定样地,采集0–10、10–20、20–30、30–40 cm土层土壤样品,测定不同恢复阶段SOC含量(CSOC)和SOC密度(DSOC),通过主成分分析方法和逐步回归分析方法分析影响CSOC、DSOC变化的主要因子。结果表明:(1)各土层CSOC、DSOC随着植被恢复呈增加趋势,且LAG显著高于其他3个恢复阶段。LAG 0–40 cm土层CSOC分别比LVR、LCQ、PLL增加12.5、9.3和4.7 g·kg–1,分别提高了248.5%、113.1%和58.5%;DSOC分别增加67.1、46.1和32.5 t C·hm–2,分别提高了182.0%、79.7%和45.6%。(2)CSOC、DSOC与群落植物多样性指数、群落总生物量、地上部分生物量、根系生物量、凋落物层现存量、凋落物层全氮(N)含量、凋落物层全磷(P)含量、土壤全磷(TP)、土壤有效磷(AP)含量、土壤C/N(除CSOC外)、C/P、N/P、<0.002 mm黏粒百分含量呈显著或极显著正相关关系,与凋落物层C/N(除DSOC外)、凋落物层C/P、土壤p H值和土壤容重呈极显著负相关关系,表明CSOC、DSOC随着植被恢复的变化受到植被因子和土壤因子诸多因子的影响。其中,土壤C/P、土壤p H值和凋落物层C/P对CSOC、DSOC影响显著;此外,<0.002 mm黏粒百分含量也显著影响着DSOC,而土壤C/P对CSOC和DSOC影响最显著。植被恢复过程中,凋落物层C/P和土壤C/P、p H值、质地的变化是影响SOC库变化的重要因素。Aims Vegetation restoration plays an important role in the accumulation and storage of soil organic carbon （SOC）. Our objectives were to investigate the effects of vegetation restoration on SOC and to explain the underlying mechanisms of carbon sequestration during vegetation restoration in the mid-subtropical China. Methods According to the disturbance intensity and the degree of restoration, we used the space-for-time sub- stitution method by selecting four different types of vegetation communities, composed of Loropetalum chinense-Vaccinium bracteatum-Rhododendron simsii scrub-grass-land （LVR）, Loropetalum ehinense-Cunninghamia lanceolata-Quereus fabri shrubbery （LCQ）, Pinus massoniana-Lithocarpus glaber-Loropetalum chinense conif- erous-broad leaved mixed forest （PLL）, and Lithocarpus glaber-Cleyera japonica-Cyclobalanopsis glauca evergreen broad-leaved forest （LAG） to represent the successional sequence in the secondary forests in Changsha County, Hunan Province, China. Permanent plots were established in each vegetation communities. Soil samples （0-40 cm） were collected and divided into four layers （0-10, 10-20, 20-30 and 30-40 cm）. Soil organic carbon concentration （Csoc） and soil organic carbon density （Dsoc） were measured. The main influencing factors on Csoc and Dsoc were analyzed with Principal Component Analysis and Stepwise Regressions Analysis. Important findings 1） Along vegetation restoration, Csoc and Dsoc increased dramatically. The Csoc was the highest in LAG, which was 12.5, 9.3 and 4.7 g·kg-1 higher than in LVR, LCQ and PLL in 0-40 cm soil depth, in- creasing by 248.5%, 113.1% and 58.5%, respectively. The increments of Dsoc in LAG at 0-40 cm soil depth were 67.1, 46.1 and 32.5 t C.hm2, and increased by 182.0%, 79.7% and 45.6% compared to Dsoc in LVR, LCQ and PLL, respectively. 2） Correlation analysis showed that Csoc and Dsoc were strongly and positively correlated with species diversity index, community total biomass, aboveground biomass, root biomass

关 键 词：湘中丘陵区 植被恢复 灌草丛 灌木林 针阔混交林 常绿阔叶林 植被因子 土壤因子 

分 类 号：S714.2[农业科学—林学]