干旱区骆驼刺群落细根生产与周转  

Fine root production and turnover of Alhagi sparsifolia community in arid area of Xin jiang,Northwest China

作　　者：冀卫萍[1] 王健健[2,3] 赵学春[2,3] 来利明[2] 王永吉[2,3] 马远见 赵春强 郑元润[2] 

机构地区：[1]山西大学环境与资源学院,太原030006 [2]中国科学院植物研究所,北京100093 [3]中国科学院大学,北京100049 [4]青城山-都江堰旅游景区管理局,四川都江堰611843

出　　处：《生态学杂志》2013年第10期2635-2640,共6页Chinese Journal of Ecology

基　　金：国家重点基础研究发展计划项目(2009CB825103)资助

摘　　要：准确理解不同生态系统植物细根的生产、周转与分解对研究陆地生态系统碳收支具有重要意义。在2010年整个生长季节内(5—10月),采用土柱法和分解袋法,对新疆干旱区骆驼刺群落的细根生物量、季节动态、分解与周转规律进行了研究。结果表明:骆驼刺群落平均月细根生物量为93.10 g·m^(-2),活细根和死细根分别占总细根生物量的72.72%和27.28%。细根生物量表现出明显的季节变化,在5—8月逐渐增加,8月达到最大值,9—10月逐渐下降。在土壤剖面垂直变化上,72.22%的活细根生物量和76.66%的死细根生物量分布在0~30 cm土层中,13.82%的活细根生物量和13.39%的死细根生物量分布在30~40 cm土层中,40 cm以下的细根生物量所占比例很小。双因素方差分析表明,不同取样时间、不同土层之间的活细根生物量、死细根生物量以及细根生产量均差异显著(P<0.05)。骆驼刺群落细根年分解率为64.52%,当细根分解量达到50%和95%时,分别需要228和1152 d。细根年净生产量为118.81 g·m^(-2),细根年周转率为1.75次。以上研究表明:骆驼刺群落的细根生产量随季节以及土壤剖面垂直变化差异显著,由于具有较慢的分解率和较高的周转率,骆驼刺群落细根对干旱区生态系统地下碳循环的分配格局具有重要意义。Fine root plays a key role in the water and nutrient uptake by plants. To accurately understand the fine root production, turnover, and decomposition is crucial for studying the carbon budget in terrestrial ecosystem. Taking the Alhagi sparsifolia community, a typical plant community in arid area of Xinjiang, as test object, and by using soil core sampling and fine root litterbags, this paper studied the fine root amount, its spatiotemporal variation, and decomposition and turnover patterns in the growth period （from May to October, 2010） of the A. sparsifolia. The monthly average fine root biomass of the community was 93.10 g·m-2, of which, live and dead ones accounted for 72.72% and 27.28%, respectively. The fine root biomass showed an obvious seasonal variation trend, i.e., increased from May, peaked in late August, and declined gradually from September to October. 72.22% of live roots and 76.66% of dead ones were distributed in 0-30 cm soil layer, 13.82% of live roots and 13.39% of dead ones were distributed in 30-40 cm soil layer, and a little proportion of live roots were in the soil layers below 40 cm. The annual decomposition rate of fine roots was 64.52%, and it took 228 days and 916 days to decompose 50% and 95% of the total fine roots, respectively. The annual net production of fine roots was 118.81 g·m-2·a-1, and the annual turnover rate of fine roots was 1.75 cycles·a-1. All the results showed that the fine root production of the A. sparsifolia community varied significantly with season and soil depth, and, due to the lower decomposition rate but higher turnover rate, the fine roots of A. sparsifolia community had great significance in the distribution pattern of underground carbon cycling in arid area ecosystem.

关 键 词：骆驼刺群落 细根生物量 细根分解 细根周转 

分 类 号：Q948.11[生物学—植物学]