N. Chilagane, J. Kashaigili, E. Mutayoba, P. Lyimo, P. Munishi, Christine Tam, N. Burgess
{"title":"小鲁阿哈河流域土地利用/覆被变化对地表产沙径流的影响","authors":"N. Chilagane, J. Kashaigili, E. Mutayoba, P. Lyimo, P. Munishi, Christine Tam, N. Burgess","doi":"10.4236/ojmh.2021.113004","DOIUrl":null,"url":null,"abstract":"Little Ruaha River catchment \n(6370 Km2) in the Southern Agricultural Growth \nCorridor of Tanzania (SAGCOT), is one of the country’s most significant \nwaterways due to its ecological composition and economic value. Regardless of \nits ecological and economical value, the regional hydrologic condition has been \ntremendously affected due to land uses alteration, influenced by different \nsocio-economic factors. This study aimed to understand the associated impacts \nof the present Land Use Land Cover (LULC) change on the surface runoff and \nsediment yield in the Little Ruaha River Catchment. Hydrological modelling \nusing Soil and Water Assessment Tool (SWAT Model) was done to quantify the \nimpact of land use and land cover dynamics on catchment water balance and sediment loads. The calibration and \nvalidation of the SWAT model were performed using sequential uncertainty \nfitting (SUFI-2). The results showed that, for the given LULC change, the \naverage annual surface runoff increased by 2.78 mm while average annual total \nsediment loading increased by 3.56 t/ha, the average annual base flow decreased \nby 2.68 mm, ground water shallow aquifer recharge decreased from 2.97 mm and a \nslight decrease in average annual ground water deep aquifer recharge by 0.14 \nmm. The model predicts that in the future, there will be a further increase in \nboth surface runoff and sediment load. Such changes, increased runoff \ngeneration and sediment yield with decreased base flow have implications on the \nsustenance flow regimes particularly the observed reduced dry season river flow \nof the Little Ruaha River, which in turn cause adverse impacts to the biotic \ncomponent of the ecosystem, reduced water storage and energy production at \nMtera Hydroelectrical dam also increasing the chances of flooding at some times \nof the year. The study recommends land use planning at the village level, and \nconservation agricultural practices to ameliorate the current situation. \nDeveloping multidisciplinary approaches for integrated catchment management is \nthe key to the sustainability of Little Ruaha River catchment.","PeriodicalId":70695,"journal":{"name":"现代水文学期刊(英文)","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2021-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"14","resultStr":"{\"title\":\"Impact of Land Use and Land Cover Changes on Surface Runoff and Sediment Yield in the Little Ruaha River Catchment\",\"authors\":\"N. Chilagane, J. Kashaigili, E. Mutayoba, P. Lyimo, P. Munishi, Christine Tam, N. Burgess\",\"doi\":\"10.4236/ojmh.2021.113004\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Little Ruaha River catchment \\n(6370 Km2) in the Southern Agricultural Growth \\nCorridor of Tanzania (SAGCOT), is one of the country’s most significant \\nwaterways due to its ecological composition and economic value. Regardless of \\nits ecological and economical value, the regional hydrologic condition has been \\ntremendously affected due to land uses alteration, influenced by different \\nsocio-economic factors. This study aimed to understand the associated impacts \\nof the present Land Use Land Cover (LULC) change on the surface runoff and \\nsediment yield in the Little Ruaha River Catchment. Hydrological modelling \\nusing Soil and Water Assessment Tool (SWAT Model) was done to quantify the \\nimpact of land use and land cover dynamics on catchment water balance and sediment loads. The calibration and \\nvalidation of the SWAT model were performed using sequential uncertainty \\nfitting (SUFI-2). The results showed that, for the given LULC change, the \\naverage annual surface runoff increased by 2.78 mm while average annual total \\nsediment loading increased by 3.56 t/ha, the average annual base flow decreased \\nby 2.68 mm, ground water shallow aquifer recharge decreased from 2.97 mm and a \\nslight decrease in average annual ground water deep aquifer recharge by 0.14 \\nmm. The model predicts that in the future, there will be a further increase in \\nboth surface runoff and sediment load. Such changes, increased runoff \\ngeneration and sediment yield with decreased base flow have implications on the \\nsustenance flow regimes particularly the observed reduced dry season river flow \\nof the Little Ruaha River, which in turn cause adverse impacts to the biotic \\ncomponent of the ecosystem, reduced water storage and energy production at \\nMtera Hydroelectrical dam also increasing the chances of flooding at some times \\nof the year. The study recommends land use planning at the village level, and \\nconservation agricultural practices to ameliorate the current situation. \\nDeveloping multidisciplinary approaches for integrated catchment management is \\nthe key to the sustainability of Little Ruaha River catchment.\",\"PeriodicalId\":70695,\"journal\":{\"name\":\"现代水文学期刊(英文)\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2021-06-28\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"14\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"现代水文学期刊(英文)\",\"FirstCategoryId\":\"1089\",\"ListUrlMain\":\"https://doi.org/10.4236/ojmh.2021.113004\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"现代水文学期刊(英文)","FirstCategoryId":"1089","ListUrlMain":"https://doi.org/10.4236/ojmh.2021.113004","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Impact of Land Use and Land Cover Changes on Surface Runoff and Sediment Yield in the Little Ruaha River Catchment
Little Ruaha River catchment
(6370 Km2) in the Southern Agricultural Growth
Corridor of Tanzania (SAGCOT), is one of the country’s most significant
waterways due to its ecological composition and economic value. Regardless of
its ecological and economical value, the regional hydrologic condition has been
tremendously affected due to land uses alteration, influenced by different
socio-economic factors. This study aimed to understand the associated impacts
of the present Land Use Land Cover (LULC) change on the surface runoff and
sediment yield in the Little Ruaha River Catchment. Hydrological modelling
using Soil and Water Assessment Tool (SWAT Model) was done to quantify the
impact of land use and land cover dynamics on catchment water balance and sediment loads. The calibration and
validation of the SWAT model were performed using sequential uncertainty
fitting (SUFI-2). The results showed that, for the given LULC change, the
average annual surface runoff increased by 2.78 mm while average annual total
sediment loading increased by 3.56 t/ha, the average annual base flow decreased
by 2.68 mm, ground water shallow aquifer recharge decreased from 2.97 mm and a
slight decrease in average annual ground water deep aquifer recharge by 0.14
mm. The model predicts that in the future, there will be a further increase in
both surface runoff and sediment load. Such changes, increased runoff
generation and sediment yield with decreased base flow have implications on the
sustenance flow regimes particularly the observed reduced dry season river flow
of the Little Ruaha River, which in turn cause adverse impacts to the biotic
component of the ecosystem, reduced water storage and energy production at
Mtera Hydroelectrical dam also increasing the chances of flooding at some times
of the year. The study recommends land use planning at the village level, and
conservation agricultural practices to ameliorate the current situation.
Developing multidisciplinary approaches for integrated catchment management is
the key to the sustainability of Little Ruaha River catchment.