红壤丘陵区典型植被群落根系生物量及碳储量研究

采用标准地法和"WinRhizo根系分析系统"平面扫描,研究了红壤丘陵区六种典型植被群落的根系特征、生物量、固碳量及土壤碳储量.结果表明:(1)根系特征值随土壤深度增加呈递减趋势,马尾松、杉木混交林和马尾松、木荷混交林土壤表层根系分布密集,特征值较大,马尾松低效林根系分布稀疏,特征值最小;(2)不同植被群落,0-40 cm土层的根系生物量所占比例在58.89%～84.88%.0-20 cm土层的土壤碳储量所占比例在35.89%～48.67%;(3)该区乔木混交林的根系生物量大于纯林和火烧迹地,植被群落的灌草覆盖度是影响根系生物量的主要因素.马尾松、木荷混交林根系净生产力最大,为6.74 t/(hm~2·a),马尾松低效林最小,为1.28t/(hm~2·a);(4)马尾松、木荷混交林的根系固碳量和土壤碳储量最大,分别为60.66 t/hm~2和9086.32 t/hm~2,马尾松低效林最小,分别为15.97 t/hm~2和1 683.75 t/hm~2,根系固碳量只占土壤碳储量的极少部分,但根系通过改良土壤结构,对增强碳源汇集和贮存、积累碳素具有重要的影响.

Study on Root Biomass and Carbon Storage of Different Vegetation Communities in Hilly Red Soil Region

With standard plots sampling method and scanning of"WinRhizo root analyzed system",root characteristics,root biomass,root carbon storage and soil carbon storage in six vegetation communities were studied in Hilly Red Soil Region.The results indicated that:(1)Root eigenvalue decrease following soil depth,there is dense root and high eigenvalue in soil surface layer of PSMF and PCMF,contrarily,sparse root and low eigenvalue in soil surface layer of PLF.(2)For 6 studied vegetation communities.the proportion of root biomass in the top 40 cm of soil varied from 58.89%to 84.88%;the proportion of soil carbon storage in the top 20cm of soil varied from 35.89%to 48.67%.(3)Root biomass of mixed forest of arbores is higher than pure forest and forest burned areas,root biomass is influenced mostly by shrub-grass cover;mean annual net productivity of root of PSMF is the best(6.74 t/hm~2·a)and that of PLF is the worst(1.28t/hm~2·a).(4)Root and soil of PSMF hold the largest carbon storage,accounting for 60.66 t/hm~2 and 9086.32 t/hm~2 respectively,and the smallest is those of PLF,for 15.97 t/hm~2and 1683.75 t/hm~2 respectively;the proportion of root carbon storage to soil carbon storage is extremely small,however,root make a great impact on carbon sequestration,reservation and accumulation by improving soil structure.