CAJ | 학술논문

土壤侵蚀条件下的碳流失问题是目前全球碳循环研究中的新点,也是土壤侵蚀基础性研究中的弱点.目前对于土壤侵蚀的研究多侧重于侵蚀造成养分流失及土地退化方面,关于土壤侵蚀对碳循环的影响研究较少.针对华南红壤侵蚀区的碳流失问题,采用室内人工模拟降雨的方法,探讨了华南典型侵蚀区两种土壤类型(林地、弃耕荒地)的有机碳流失过程,主要取得以下一些成果,(1)土壤有机碳的流失主要以侵蚀泥沙为载体,两种土壤(林地、弃耕荒地)坡面的泥沙有机碳含量均表现出随降雨历时逐渐减小的趋势,但雨强和坡度对侵蚀泥沙中有机碳含量的影响没有明显规律;林地土壤坡面的侵蚀泥沙中有机碳含量明显高于弃耕荒地土壤坡面的侵蚀泥沙中有机碳含量.(2)林地土壤的泥沙有机碳富集比大于弃耕荒地的泥沙有机碳富集比,林地土壤有机碳富集比变化范围为0.99~1.65,而弃耕荒地土壤有机碳富集比变化范围为0.86~1.07;林地土壤的有机碳流失率大于弃耕荒地的有机碳流失率.林地土壤的有机碳流失率变化范围为 1.6%~18.9%,弃耕荒地土壤的为2.2%~10.4%.土壤有机碳流失率随降雨雨强的增加而增大,坡度对土壤有机碳流失率的影响不显著.(3)土壤有机碳流失强度与侵蚀强度呈明显的线性正相关关系,试验条件下(不同地类土壤、雨强、坡度)土壤有机碳流失强度与侵蚀强度间的函数关系可表达为:y(SOC)=5.104x(Erosion)+0.036(r2=0.984).
토양침식조건하적탄류실문제시목전전구탄순배연구중적신점,야시토양침식기출성연구중적약점.목전대우토양침식적연구다측중우침식조성양분류실급토지퇴화방면,관우토양침식대탄순배적영향연구교소.침대화남홍양침식구적탄류실문제,채용실내인공모의강우적방법,탐토료화남전형침식구량충토양류형(임지、기경황지)적유궤탄류실과정,주요취득이하일사성과,(1)토양유궤탄적류실주요이침식니사위재체,량충토양(임지、기경황지)파면적니사유궤탄함량균표현출수강우력시축점감소적추세,단우강화파도대침식니사중유궤탄함량적영향몰유명현규률;임지토양파면적침식니사중유궤탄함량명현고우기경황지토양파면적침식니사중유궤탄함량.(2)임지토양적니사유궤탄부집비대우기경황지적니사유궤탄부집비,임지토양유궤탄부집비변화범위위0.99~1.65,이기경황지토양유궤탄부집비변화범위위0.86~1.07;임지토양적유궤탄류실솔대우기경황지적유궤탄류실솔.임지토양적유궤탄류실솔변화범위위 1.6%~18.9%,기경황지토양적위2.2%~10.4%.토양유궤탄류실솔수강우우강적증가이증대,파도대토양유궤탄류실솔적영향불현저.(3)토양유궤탄류실강도여침식강도정명현적선성정상관관계,시험조건하(불동지류토양、우강、파도)토양유궤탄류실강도여침식강도간적함수관계가표체위:y(SOC)=5.104x(Erosion)+0.036(r2=0.984).
Soil carbon loss in erosion is not only the one of new topics in global carbon cycle research, but also the key problem in soil physical study. Most previous studies focused on nutrient loss in soil erosion and land degeneration, but few attentions have been paid to soil carbon loss complaining with soil erosion. This study used simulated rainfall method to investigate the influences of soil type, rainfall intensity and slope gradient on soil organic carbon loss. The results showed that: (1) Soil organic carbon loss is major in losing with sediment and the content of soil organic carbon in sediment decrease with rainfall duration. There are no obvious relation between rainfall intensity and the content of soil organic carbon in sediment. The content of soil organic carbon in sediment from forest land treatment is greater than that from abandoned land treatment. (2) The enrichment ratio of soil organic carbon in sediment for forest land treatment is also higher than it for abandoned land treatment. For forest land treatment, the enrichment ratio of soil organic carbon in sediment ranges from 0.99 to 1.65. But for abandoned land treatment, it ranges from 0.86 to 1.07. The soil organic carbon loss rate of forest land treatment is greater than that abandoned land treatment. For forest land treatment it ranges from 1.6% to 18.9%, and 2.2% to 10.4% for abandoned land treatment. The soil organic carbon loss rate increases with rainfall intensity, but no obvious tendency can be found with increased slope gradient. And (3) there are lineally relationship between the soil organic carbon loss rate and soil erosion rate. The function of them under different soil type, rainfall intensity, and soil slope can be expressed as:y(SOC)=5.104x(Erosion)+0.036 (r2=0.984).