Characteristics of decomposition of dissolved organic carbon by microbes in water of forest ecosystems

森林生态系统水中微生物分解溶解有机碳的特征

基本信息

批准号：
14560116
负责人：
TODA Hiroto
金额：
$ 2.24万
依托单位：
National University Corporation Tokyo University of Agriculture and Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

项目摘要

A flow-through bioreactor method is useful for measurement of biodegradable dissolved organic carbon(BDOC) in water of forest ecosystems. We determined the condition of BDOC measurement as follows ; over 20℃ for air temperature, 0.25 ml/min for solution flow rate and 10 mg/L for DOC concentration of samples. The percentages of BDOC on DOC(BDOC%) in percolated water of organic layer were 20-30% in Japanese cedar (Cryptomeria japonica), Japanese cypress (Chamecyparis obutsa) and red pine (Pinus densiflora) stand, while 50% in mizunara (Quercus mongolica var.grosseserrata) stand. This result suggested that the large amount of nitrogen influenced the BDOC% in mizunara stand.In a small watershed of aged Japanese cedar and cypress plantation, DOC in order of high concentrations were organic layer percolation > through fall > precipitation, and was rapidly low in soil water. The DOC annual discharge in steam water was small (6.4 kg/ha), suggesting the DOC in soil water was consumed by soil microbes and adsorbed on soil colloid. The amount of consumption of water soluble organic carbon (WSOC) had positive correlations with the rate of carbon mineralization in surface soil. Therefore, DOC and WSOC amounts were important indicators for microbe activities. However, these amounts were remarkably smaller than mineralized carbon, so we considered that determination of available organic carbon was necessary.The percentages of lignin on humus increased with increases of decomposition class in forest floor of six species. Especially, the organic carbon in the humus class insoluble by alkaline solution had 70% of carbon in lignin. On the other hand, the amounts of lignin decreased with decreases of mass weight due to decomposition of the leaf litter of six deciduous broad-leaved trees species. We need to make more detailed classification of organic matter, such as easily or hard decomposed lignin.

流通生物反应器方法是在森林水中使用可生物降解的有机碳（BDOC），以下是BDOC测量的状况，如下20°C，温度为0.25 ml/min用于样品的文件。 Mongolica var.Grosssseserata）表明，大量的llogen在Mizunara Stand中封闭了BDOC％。土壤中的水很小（6.4 kg/ha），这表明土壤中的DOC被土壤微生物消耗掉，并在土壤胶体上吸附因此，土壤中的碳化量在六个物种的森林地板上，腐殖质的有机碳在木质素中的碳含量为70％需要对有机物或硬分解木质素进行更详细的分类。