Carbon (C), nitrogen (N), and phosphorous (P) levels and their stoichiometry in plant components (leaves, branch trunks, roots) of trees in a karst forest and non-karst forest are compared. The results show that the C...Carbon (C), nitrogen (N), and phosphorous (P) levels and their stoichiometry in plant components (leaves, branch trunks, roots) of trees in a karst forest and non-karst forest are compared. The results show that the C contents, C:N and C:P ratios of dominant species in the karst forest were lower than those in the non-karst forest, but the N and P and the N:P ratio were higher;C:N:P ratios in plant organs of trees in the karst forest were in the order of trunks>roots>branches>leaves. However, C:N:P ratio in the non-karst forest trees were trunks>branches>roots>leaves. Moreover, ratio of C:N:P in trunks was highest and lowest in leaves in both forests. In non-karst forest trees, N:P was in the order of leaves> roots>branches>trunks. There were no significant differences in the ratio of N:P in different plant components of trees in the karst forest. However, in karst and non-karst forest trees, the ratio of N:P in leaves was highest;positive correlations between N and P contents, and N and N:P ratios were observed in both karst and non-karst forests (p<0.001). Negative correlations between P and N:P ratios (p<0.05) were observed in karst forest trees, while positive correlations were observed in non-karst forest trees.展开更多
The formation mechanism and influencing factors identification of soil erosion are the core and frontier issues of current research.However,studies on the multi-factor synthesis are still relatively lacked.In this stu...The formation mechanism and influencing factors identification of soil erosion are the core and frontier issues of current research.However,studies on the multi-factor synthesis are still relatively lacked.In this study,the simulation of soil erosion and its quantitative attribution analysis have been conducted in different geomorphological types in a typical karst basin based on the RUSLE model and the geodetector method.The influencing factors,such as land use type,slope,rainfall,elevation,lithology and vegetation cover,have been taken into consideration.Results show that the strength of association between the six influencing factors and soil erosion was notably different in diverse geomorphological types.Land use type and slope were the dominant factors of soil erosion in the Sancha River Basin,especially for land use type whose power of determinant(q value)for soil erosion was much higher than other factors.The q value of slope declined with the increase of relief in mountainous areas,namely it was ranked as follows:middle elevation hill>small relief mountain>middle relief mountain.Multi-factors interactions were proven to significantly strengthen soil erosion,particularly for the combination of land use type with slope,which can explain 70%of soil erosion distribution.It can be found that soil erosion in the same land use type with different slopes(such as dry land with slopes of 5°and above 25°)or in the diverse land use types with the same slope(such as dry land and forest with a slope of 5°),varied much.These indicate that prohibiting steep slope cultivation and Grain for Green Project are reasonable measures to control soil erosion in karst areas.Based on statistics of soil erosion difference between diverse stratifications of each influencing factor,results of risk detector suggest that the amount of stratification combinations with significant difference accounted for 55%at least in small relief mountain and middle relief mountainous areas.Therefore,the spatial heterogeneity of soil erosion and its展开更多
Ecological restoration refers to the containment of soil erosion,restoration of water conservation,climate regulation,maintenance of ecological functions of biodiversity,and improvement of ecological environment and l...Ecological restoration refers to the containment of soil erosion,restoration of water conservation,climate regulation,maintenance of ecological functions of biodiversity,and improvement of ecological environment and landscape pattern based on self-repairing capacity of the nature and combined with appropriate artificial measures. Since the natural restoration process of karst desertification mountain is very long,it needs to be supplemented by artificial vegetation restoration. This paper introduced the ecological restoration technologies implemented in karst rocky desertification mountains in Xixiu District,Anshun City of Guizhou Province,and also introduced the afforestation tending management measures. It assessed the ecological benefits of the ecological restoration project from five aspects: mountain community characteristics,vegetation coverage,species diversity,afforestation survival rate and landscape effect.展开更多
基金the National Natural Science Foundation of China (31360123)National Key Scientific Research Project (2013CB956701)Applied and Basic Research Program of Guizhou Province ([2014]200208).
文摘Carbon (C), nitrogen (N), and phosphorous (P) levels and their stoichiometry in plant components (leaves, branch trunks, roots) of trees in a karst forest and non-karst forest are compared. The results show that the C contents, C:N and C:P ratios of dominant species in the karst forest were lower than those in the non-karst forest, but the N and P and the N:P ratio were higher;C:N:P ratios in plant organs of trees in the karst forest were in the order of trunks>roots>branches>leaves. However, C:N:P ratio in the non-karst forest trees were trunks>branches>roots>leaves. Moreover, ratio of C:N:P in trunks was highest and lowest in leaves in both forests. In non-karst forest trees, N:P was in the order of leaves> roots>branches>trunks. There were no significant differences in the ratio of N:P in different plant components of trees in the karst forest. However, in karst and non-karst forest trees, the ratio of N:P in leaves was highest;positive correlations between N and P contents, and N and N:P ratios were observed in both karst and non-karst forests (p<0.001). Negative correlations between P and N:P ratios (p<0.05) were observed in karst forest trees, while positive correlations were observed in non-karst forest trees.
基金National Basic Research Program of China,No.2015CB452702National Natural Science Foundation of China,No.41671098,No.41530749.
文摘The formation mechanism and influencing factors identification of soil erosion are the core and frontier issues of current research.However,studies on the multi-factor synthesis are still relatively lacked.In this study,the simulation of soil erosion and its quantitative attribution analysis have been conducted in different geomorphological types in a typical karst basin based on the RUSLE model and the geodetector method.The influencing factors,such as land use type,slope,rainfall,elevation,lithology and vegetation cover,have been taken into consideration.Results show that the strength of association between the six influencing factors and soil erosion was notably different in diverse geomorphological types.Land use type and slope were the dominant factors of soil erosion in the Sancha River Basin,especially for land use type whose power of determinant(q value)for soil erosion was much higher than other factors.The q value of slope declined with the increase of relief in mountainous areas,namely it was ranked as follows:middle elevation hill>small relief mountain>middle relief mountain.Multi-factors interactions were proven to significantly strengthen soil erosion,particularly for the combination of land use type with slope,which can explain 70%of soil erosion distribution.It can be found that soil erosion in the same land use type with different slopes(such as dry land with slopes of 5°and above 25°)or in the diverse land use types with the same slope(such as dry land and forest with a slope of 5°),varied much.These indicate that prohibiting steep slope cultivation and Grain for Green Project are reasonable measures to control soil erosion in karst areas.Based on statistics of soil erosion difference between diverse stratifications of each influencing factor,results of risk detector suggest that the amount of stratification combinations with significant difference accounted for 55%at least in small relief mountain and middle relief mountainous areas.Therefore,the spatial heterogeneity of soil erosion and its
基金Supported by the Construction Science and Technology Plan Program of Chongqing'Study on Landscape and Ecological Restoration Technology for Karst Rocky Desertification Landforms'(2015-1-19).
文摘Ecological restoration refers to the containment of soil erosion,restoration of water conservation,climate regulation,maintenance of ecological functions of biodiversity,and improvement of ecological environment and landscape pattern based on self-repairing capacity of the nature and combined with appropriate artificial measures. Since the natural restoration process of karst desertification mountain is very long,it needs to be supplemented by artificial vegetation restoration. This paper introduced the ecological restoration technologies implemented in karst rocky desertification mountains in Xixiu District,Anshun City of Guizhou Province,and also introduced the afforestation tending management measures. It assessed the ecological benefits of the ecological restoration project from five aspects: mountain community characteristics,vegetation coverage,species diversity,afforestation survival rate and landscape effect.