摘要
细根对植物群落功能的发挥和土壤碳库及全球碳循环具有重要意义。采用土柱法和分解袋法,于2010年5—10月整个生长季内,对三工河流域梭梭(Haloxylon ammodendron)群落的细根生物量以及分解和周转规律进行研究。结果表明,梭梭群落细根生物量呈现明显的季节变化,5—8月逐渐增加,8月达到最大,9—10月逐渐下降。细根生物量月平均值为183.76 g·m-2。活细根和死细根生物量分别占细根总生物量的72.59%和27.41%。梭梭群落细根生物量表现出明显的垂直变化,随土壤深度的增加而呈现先增加后逐渐降低的趋势,其中51.36%的活细根和51.81%的死细根生物量分布在>10～30 cm土层。梭梭群落细根年分解率为58.76%,达到50%和95%分解率所需时间为279和1 302 d。梭梭群落细根净生产力为110.73 g·m-2·a-1,年周转速率为1.25次。
Fine root plays a significant role in plant community performance of functions,soil carbon pool and global carbon recycling.Observation was done of biomass,decomposition and turnover of the fine roots of Haloxylon ammodendron communities in the Sanjiang River Valley throughout the whole growing season from May to October in 2010,using soil column method and litter bag method.Results show that fine root biomass of the H.ammodendron communities varied significantly with seasons.It increased gradually in the period from May to August,peaked in August,and then declined gradually in September and October,and its monthly average reached 183.76 g · m-2,of which live fine root accounted for 72.59％ and dead one for 27.41％.And its distribution varied with soil depth,showing a trend of increasing first and then declining,with a major portion distributed in ＞ 10-30 cm soil layer,accounting for 51.36％ of the live fine root and 51.81％ of the dead one.The annual decomposition rate of the fine root was 58.76％.It took 279 and 1 302 days for the decomposition rate to reach 50％ and 95％,respectively.The net productivity of the fine root was 110.73 g · m-2 · a-1,and its annual turnover rate was 1.25 times · a-1.In conclusion,the fine root production of H.ammodendron communities varied significantly with season and soil depth.These findings suggest that the fine roots of H.ammodendron communities are of great significance for underground carbon recycling in the arid area.
出处
《生态与农村环境学报》
CAS
CSSCI
CSCD
北大核心
2013年第5期666-670,共5页
Journal of Ecology and Rural Environment
基金
国家重点基础研究发展计划(2009CB825103)
关键词
梭梭
细根周转
生物量
土壤有机碳
Haloxylon ammodendron
fine root turnover
biomass
soil organic carbon
