A soil conservation project was implemented in Tanzania for over 30 years.This study applied a socio-economic approach to examine and analyse the benefits of soil conservation in the Kondoa eroded area of Tanzania by ...A soil conservation project was implemented in Tanzania for over 30 years.This study applied a socio-economic approach to examine and analyse the benefits of soil conservation in the Kondoa eroded area of Tanzania by conducting a household survey of 240 households.The study findings show that 89%and 70%of respondents consider soil conservation activities have increased vegetation and soil fertility,respectively.Decreased soil erosion was perceived by 68%of respondents,increased firewood by 98%,increased fodder by 50%,high crop yields by 56%,and food sufficiency by 68%.These are the outcomes of conservation tillage,integrated farming and use of organic fertilizers,controlled stall feeding,agroforestry,construction of cut off drains,contour bunds and contour ridges cultivation,which are the main land use practices in the area.Access to extension services,household sizes,long term land ownership,crop incomes and awareness of soil conservation project were found to determine the level of participation in soil conservation.Major challenges are the lack of sustainability of those activities because of a recent policy decision to withdraw conservation investment.Despite the challenge,this study concluded that past government efforts on soil conservation activities initiated since the early 1970s through decentralization,institutional collaboration,socioeconomic support to farmers and continuous local community participation in restoring the degraded ecosystem of Kondoa have contributed to ensure environmental and socio-economic sustainability in the area.展开更多
The poor growth of understory vegetation and the severe losses of soil and water in Pinus massoniana forests have recently become serious concerns in an area in southern China with eroded red soil.The influence of top...The poor growth of understory vegetation and the severe losses of soil and water in Pinus massoniana forests have recently become serious concerns in an area in southern China with eroded red soil.The influence of topography on the spatial distribution of vegetation,however,has received little attention.This study combined several multivariate analyses to discern the complicated relationship between understory vegetation and topography.Thirty-six plots(10 m×10 m)were sampled in a field survey of the vegetation and topography in the central red-soil region.The distributions of the understory vegetation differed significantly amongst the topographies.Most plants grew in gullies,and few grew on ridges.The low coverage(25.2%)and number of species(5 per plot)of the vegetation on ridges was due to serious soil erosion.Surface curvature and slope aspect were the first and second most important topographic factors,respectively,affecting the distribution of the vegetation.The relationship between topography and distribution could be described by a linear model.Surface curvature or slope aspect alone,however,could only explain 22.2-59.2%of the variance in distribution.The adaptation of vegetation to specific topographies should be considered for restorations of P.massoniana forests in the study area.The results of this study will be helpful for selecting potential sites for seeding and vegetation restoration to improve the ecology of the study area.Further studies will be needed to identify the mechanism of the distribution of the understory vegetation in these P.massoniana forests.展开更多
基金The study was funded from the World Bank through the Ministry of Livestock Development and Fisheries of Tanzania and the Asian Institute of Technology,Thailand.We thank various organizations,the communities and individuals in the study area for their kind assistance and necessary cooperation during the study.Constructive comments and suggestions of anonymous reviewers highly improved the manuscript quality and their support is greatly appreciated.
文摘A soil conservation project was implemented in Tanzania for over 30 years.This study applied a socio-economic approach to examine and analyse the benefits of soil conservation in the Kondoa eroded area of Tanzania by conducting a household survey of 240 households.The study findings show that 89%and 70%of respondents consider soil conservation activities have increased vegetation and soil fertility,respectively.Decreased soil erosion was perceived by 68%of respondents,increased firewood by 98%,increased fodder by 50%,high crop yields by 56%,and food sufficiency by 68%.These are the outcomes of conservation tillage,integrated farming and use of organic fertilizers,controlled stall feeding,agroforestry,construction of cut off drains,contour bunds and contour ridges cultivation,which are the main land use practices in the area.Access to extension services,household sizes,long term land ownership,crop incomes and awareness of soil conservation project were found to determine the level of participation in soil conservation.Major challenges are the lack of sustainability of those activities because of a recent policy decision to withdraw conservation investment.Despite the challenge,this study concluded that past government efforts on soil conservation activities initiated since the early 1970s through decentralization,institutional collaboration,socioeconomic support to farmers and continuous local community participation in restoring the degraded ecosystem of Kondoa have contributed to ensure environmental and socio-economic sustainability in the area.
基金This study was funded by the National Natural Science Foundation of China(Grant number 41201276).
文摘The poor growth of understory vegetation and the severe losses of soil and water in Pinus massoniana forests have recently become serious concerns in an area in southern China with eroded red soil.The influence of topography on the spatial distribution of vegetation,however,has received little attention.This study combined several multivariate analyses to discern the complicated relationship between understory vegetation and topography.Thirty-six plots(10 m×10 m)were sampled in a field survey of the vegetation and topography in the central red-soil region.The distributions of the understory vegetation differed significantly amongst the topographies.Most plants grew in gullies,and few grew on ridges.The low coverage(25.2%)and number of species(5 per plot)of the vegetation on ridges was due to serious soil erosion.Surface curvature and slope aspect were the first and second most important topographic factors,respectively,affecting the distribution of the vegetation.The relationship between topography and distribution could be described by a linear model.Surface curvature or slope aspect alone,however,could only explain 22.2-59.2%of the variance in distribution.The adaptation of vegetation to specific topographies should be considered for restorations of P.massoniana forests in the study area.The results of this study will be helpful for selecting potential sites for seeding and vegetation restoration to improve the ecology of the study area.Further studies will be needed to identify the mechanism of the distribution of the understory vegetation in these P.massoniana forests.
