Dendrogeomorphological method was used to study soil erosion in two typical karst sites （Puding and Zhengfeng） in Guizhou Province, China. Eleven pairs of exposed and unexposed tree roots were measured in the field ...Dendrogeomorphological method was used to study soil erosion in two typical karst sites （Puding and Zhengfeng） in Guizhou Province, China. Eleven pairs of exposed and unexposed tree roots were measured in the field and sampled for anatomical characteristics. The results showed that the exposed roots recorded karst soil erosion. Significant changes were shown in the anatomical characteristics of the exposed tree roots when soil erosion occurred, such as suddenly narrower tree rings, smaller cells, and fewer earlywood cells. Meanwhile, the fabre lumen and vessel lumen areas markedly declined to the range of 39.20% to 70.66%, which only slightly implies soil erosion. The accurate time period during which soil erosion occurred was identified and combined with the age of the tree roots. Dynamics of soil erosion were calculated and soil erosion recorded by the exposed roots from 2002 to 2007 at an average rate of 0.484 t y^-1 at Puding, and from 2005 to 2007 at an average rate of 0.051 t y^-1 at Zhenfeng. Karst soil erosion was recorded by not only one species but by multi species of broadleaf tree roots, which can significantly enhance the study of karst soil erosion through the use of Dendrogeomorphological method. The quantity of eroded soil was found to be extremely large when records from the exposed tree roots were compared with estimates from site measurements of runoff. The major type of karst soil erosion was underground soil loss and this comprised approximately 2/3 of total erosion.展开更多
Due to the unique environment of karst landscapes, there are many uncertainties regarding the recovery of vegetation following human disturbance. Through standard wood parsing and growth ring investigation in Puding c...Due to the unique environment of karst landscapes, there are many uncertainties regarding the recovery of vegetation following human disturbance. Through standard wood parsing and growth ring investigation in Puding county in Guizhou province, China, we studied the process of vegetation restoration in karst areas. According to our results, during the recovery of karst vegetation height increases and ground diameter enlargement of tree layers occurred. Increases in the height and ground diameter followed logarithmic and growth curves, respectively. The development time of trees showed continuity, and growth points were randomly distributed. However, with large propagule quantities, vegetation can be directly restored and developed into a secondary high forest without a grass filling stage, and the recovery time is shortened.展开更多
基金the National Key Basic Research Development Program(2013CB956702)Great Basic Research Fund of the Chinese Academy of Sciences(XDA05070405)+2 种基金the International Scientific Project of Guizhou(QKHWGZ-2010-7009)Great Basic Research Fund of Guizhou Province(QKH-JZ-2014-200203)100 High Level Innovating Project(QKHRC-2015-4022)
文摘Dendrogeomorphological method was used to study soil erosion in two typical karst sites （Puding and Zhengfeng） in Guizhou Province, China. Eleven pairs of exposed and unexposed tree roots were measured in the field and sampled for anatomical characteristics. The results showed that the exposed roots recorded karst soil erosion. Significant changes were shown in the anatomical characteristics of the exposed tree roots when soil erosion occurred, such as suddenly narrower tree rings, smaller cells, and fewer earlywood cells. Meanwhile, the fabre lumen and vessel lumen areas markedly declined to the range of 39.20% to 70.66%, which only slightly implies soil erosion. The accurate time period during which soil erosion occurred was identified and combined with the age of the tree roots. Dynamics of soil erosion were calculated and soil erosion recorded by the exposed roots from 2002 to 2007 at an average rate of 0.484 t y^-1 at Puding, and from 2005 to 2007 at an average rate of 0.051 t y^-1 at Zhenfeng. Karst soil erosion was recorded by not only one species but by multi species of broadleaf tree roots, which can significantly enhance the study of karst soil erosion through the use of Dendrogeomorphological method. The quantity of eroded soil was found to be extremely large when records from the exposed tree roots were compared with estimates from site measurements of runoff. The major type of karst soil erosion was underground soil loss and this comprised approximately 2/3 of total erosion.
基金the National Key Basic Research Development Program(2013CB956702)Great Basic Research Fund of the Chinese Academy of Sciences(XDA05070405)+1 种基金Great Basic Research Fund of Guizhou Province(QKH-JZ-2014-200203)100 High Level Innovating Project(QKHRC-2015-4022)
文摘Due to the unique environment of karst landscapes, there are many uncertainties regarding the recovery of vegetation following human disturbance. Through standard wood parsing and growth ring investigation in Puding county in Guizhou province, China, we studied the process of vegetation restoration in karst areas. According to our results, during the recovery of karst vegetation height increases and ground diameter enlargement of tree layers occurred. Increases in the height and ground diameter followed logarithmic and growth curves, respectively. The development time of trees showed continuity, and growth points were randomly distributed. However, with large propagule quantities, vegetation can be directly restored and developed into a secondary high forest without a grass filling stage, and the recovery time is shortened.
