苦竹林植硅体碳与硅的研究  

Study on Phytolith-occluded Organic Carbon and Silicon in a Pleioblastus amarus Forest

作　　者：杨杰[1] 吴家森[1,2] 姜培坤[1,2] 赵培平 

机构地区：[1]浙江农林大学环境与资源学院,浙江临安311300 [2]浙江农林大学浙江省森林生态系统碳循环与固碳减排重点实验室,浙江临安311300

出　　处：《自然资源学报》2016年第2期299-309,共11页Journal of Natural Resources

基　　金：国家自然科学基金项目(31270667;41471197);浙江省林业碳汇与计量科技创新团队(2012R50030)~~

摘　　要：植硅体碳(phytolith-occluded organic carbon,PhytOC)具有很强的抗风化能力,能存在于土壤中达数千年之久,成为陆地土壤长期固碳的重要机制。论文以中国亚热带地区苦竹(Pleioblastus amarus)林生态系统为对象,探究硅、植硅体及植硅体碳在竹林生态系统中的分布特征。研究结果表明,植硅体碳广泛分布于苦竹地上部分各器官中,植硅体和植硅体碳含量均为叶>枝>秆。被传统植硅体研究所忽略的竹枝和竹秆中的植硅体碳储量占到地上部分植硅体碳总储量的7.2%和51.1%。植硅体碳占总有机碳的比例在叶、枝、秆中分别为0.59%、0.21%和0.28%,植硅体碳占总有机碳的比例因积累器官的不同而存在明显的差异。植物体内植硅体的含量与土壤中植物可利用硅的含量之间存在显著的线性相关关系(R2=0.91,P<0.05),而与土壤中总硅无相关性(R2=0.16,P>0.05)。苦竹林植硅体碳封存速率为40.2 kg·hm-2·a-1。Phytolith-occluded organic carbon （PhytOC） can exist in the soil for thousand years, thus it is an important mechanism of long-term carbon sequestration in soils. In this study, Pleioblastus amarus forest in subtropical China was selected as experimental materials to discuss the distribution of silicon, phytolith, and PhytOC in a Pleioblastus amarus forest system. A microwave digestion method was used in this study to isolate phytolith from plant material and soil samples, and the PhytOC were determined by alkali dissolution- spectrophotometry method. The results showed that the contents of phytolith and PhytOC in a Pleioblastus amarus forest system decreased in the order： leaf 〉 branch 〉 culms. For different organs, there was significant linear correlation between Si content and phytolith content （R2 =0.98, P〈 0.01）, and between phytolith content and PhytOC content （R 2= 0.52, P〈 0.01）, and there was significant negative linear correlation between total organic carbon content and PhytOC content （R2 = 0.57, P 〈 0.01）, and between organic carbon content in phytolith and phytolith content （R2 = 0.17, P〈 0.01）. The PhytOC stocked in branches and culms accounted for 17.2% and 51.1% of total PhytOC stock in above-ground part, respectively. PhytOC stocked in leaves, branches and culms accounted for 0.59%, 0.21% and 0.28% of total organic carbon stock, respectively. The ratios of PhytOC/total organic carbon greatly varied in different organs. The phytolith contents in bamboo plants were linearly correlated with plant-available Si contents in the soil （R2 = 0.91, P〈 0.05）, but poorly correlated with total Si contents in the soil （R2 = 0.16, P〉 0.05）. The PhytOC production rate in the Pleioblastus amarus forest system studied was 40.2 kg· hm-2· a-1.

关 键 词：苦竹 器官 硅 植硅体 植硅体碳 

分 类 号：S795[农业科学—林木遗传育种]