%0 Journal Article %T 极端暴雨下裸地坡面径流及壤中流中碳素输移特征 %T Carbon Loss with Slope Surface Runoff and Interflow on Bare Slopes as Affected by Severe Rainstorm %A 费 凯 %A 张丽萍 %A 邓龙洲 %A 孙天宇 %A 范晓娟 %A FEI,Kai %A ZHANG,Liping %A DENG,Longzhou %A SUN,Tianyu %A FAN,Xiaojuan %J 土壤学报 %J ACTA PEDOLOGICA SINICA %@ 0564-3929 %V 57 %N 3 %D 2020 %P 623-635 %K 浙闽丘陵;风化花岗岩母质土壤;红土层;土壤总碳流失浓度;模拟降雨 %K Zhejiang-Fujian hilly region; Soil derived from weathered granite; Laterite layer; Total carbon loss mass concentration; Rainfall simulation %X 采用人工模拟降雨的方法,研究了不同雨强(90、120、150 mm•h-1)和坡度(5°、8°、15°、25°)条件下,南方风化花岗岩母质土壤红土层裸地降雨坡面径流和壤中流中总碳(Total carbon,TC)的流失量及流失过程,并分析了雨强和坡度对TC流失量的影响。结果表明,在坡面径流中,坡度和雨强的增大对碳素质量浓度变化过程影响较小,且流失率曲线与质量浓度曲线呈极显著相关关系,TC流失率变化主要受质量浓度的影响;在壤中流中,TC质量浓度曲线呈现出迅速上升达到最大值后缓慢下降直至平稳的趋势;在试验条件范围内,各坡度条件下,随着雨强的增大,坡面径流中TC流失量增大,而壤中流中TC流失量减小;在大雨强下,坡面径流中TC流失量与坡度没有明显的线性关系,而随着雨强的增大,坡度与壤中流中TC流失量线性关系明显增加;在试验雨强和坡度下,雨强对TC流失总量和坡面径流中TC流失量的影响较坡度更显著,而在壤中流中坡度的影响则更显著。径流中碳素流失量与雨强、坡度及场降雨径流总量之间均有明显的线性关系, R2>0.800。结果可为我国南方风化花岗岩母质土壤裸坡径流中TC单位面积流失量的估算提供依据。 %X 【Objective】According to the International Plant Protection Convention (IPPC), it is estimated that soil carbon loss contributes to the global atmospheric CO2 concentration by about 30%~50%, and about 50%~70% of the loss is caused by soil erosion. Therefore, the loss of soil carbon through soil erosion has an important impact on carbon recycling and exchanging between terrestrial ecosystems and the atmosphere, and it plays a significant role in balancing the global CO2 concentration and climate warming. Most studies on nutrient loss in China focus mainly on that in the loess plateau region and the purple soil region and pay attention mainly to nitrogen and phosphorous loss or TC loss with slope surface runoff, but almost neglect effects of the two factors, slope gradient and rainfall intensity, on TC loss with interflow in soil, let alone dynamic process of TC loss distribution in slope surface runoff and interflow. Therefore, this study was done to explore characteristics of soil total carbon (TC) loss with slope surface runoff and interflow on bare slopes of the soil derived from weathered granite in the Zhejiang-Fujian hilly region, China.【Method】 In this study an artificial rainfall simulation experiment was carried out to explore TC loss with slope surface runoff and interflow and its processes as affected by slope gradient and rainfall intensity and to analyze effects of the two on TC loss. So it was designed tot have 3 levels of rainfall intensity (60, 90 and 150 mm•h-1) and four levels of slope gradient (5, 8, 15 and 25°), performed on two three-dimensional monitoring simulator runoff flumes, arranged in parallel. TC loss from each flume was monitored and calcuated.【Result】Results show that variation of the TC loss process with slope surface runoff was not much affected by slope gradient or rainfall intensity, and the TC loss rate variation curve was extra-significantly correlated with the mass concentration curve. That is to say, TC loss rate was affected mainly by TC mass concentration. In soil interflow, TC mass concentration curve peaked up rapidly and then declined and leveled off. In the experiment, TC loss with runoff increased with rising rainfall intensity, regardless of slope gradient, while TC loss with interflow decreased. No apparent linear relationship was found between TC loss with runoff and slope gradient under high rainfall intensities, while a linear relationship was looming between slope gradient and TC loss in the interflow. The influence of rainfall intensity on total TC loss and TC loss with runoff was more significant than that of slope gradient, but a reverse trend was observed in interflow. TC loss with runoff was found to be significantly and linearly related to rainfall intensity, slope gradient and runoff volume per rainfall event, with R2 being higher than 0.800. 【Conclusion】In summary, TC loss increases gradually with rising slope gradient and rainfall intensity. Slope surface runoff is the main factor affecting TC loss, but interflow is one that can not be ignored. This study provides a calculation method for estimating TC losses with surface runoff on bare slopes of the soil derived from weathered granite in the Zhejiang-Fujian hilly region, China. %R 10.11766/trxb201812150531 %U http://pedologica.issas.ac.cn/trxb/home %1 JIS Version 3.0.0