Impacts of climate and land use/cover changes on streamflow at Kibungo sub-catchment, Tanzania

The impacts of changing climate and land use/cover on streamflow in the Kibungo sub-catchment were evaluated using the Soil and Water Assessment Tool (SWAT). Rainfall, minimum, and maximum temperature data for six stations from the ensemble mean of the RCMs (RCA4, RACMO22T, CCLM4-8-17) were used und...

Full description

Bibliographic Details
Main Authors: Lusajo Henry Mfwango, Tenalem Ayenew, Henry F. Mahoo
Format: Article
Language:English
Published: Elsevier 2022-11-01
Series:Heliyon
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2405844022025737
_version_ 1811320600156700672
author Lusajo Henry Mfwango
Tenalem Ayenew
Henry F. Mahoo
author_facet Lusajo Henry Mfwango
Tenalem Ayenew
Henry F. Mahoo
author_sort Lusajo Henry Mfwango
collection DOAJ
description The impacts of changing climate and land use/cover on streamflow in the Kibungo sub-catchment were evaluated using the Soil and Water Assessment Tool (SWAT). Rainfall, minimum, and maximum temperature data for six stations from the ensemble mean of the RCMs (RCA4, RACMO22T, CCLM4-8-17) were used under RCP 4.5 and RCP 8.5. The homogeneity and trend test were used to detect the change point and identify the pattern in the annual time series, respectively. Land Change Modeler (LCM) was used to predict land use maps of 2040 and 2070 from historical maps. Streamflow was simulated for 2021–2040 and 2041–2070 based on the homogeneity test results. The model calibration (2009–2016) and validation (2009–2016) for streamflow were successful. The homogeneity test detects a change point in 2040. A significant decrease in annual rainfall by 22.9 mm/yr (RCP 4.5) and 57 mm/yr (RCP 8.5) for 2021–2040 and an insignificant decrease was obtained during 2041–2070 under both emission scenarios. The annual temperature increased insignificantly by 0.004 °C/yr under RCP 4.5 while a significant increase of 0.21 °C/yr under RCP 8.5 was observed for 2021–2040. For 2041–2070, a significant increase of 0.016 °C/yr (RCP 4.5) and 0.045 °C/yr (RCP 8.5) was observed. The change in land use/cover resulted in increasing the build-up area (84%), agricultural fields (55.6%), and a decrease in the forest area (10.5%) during 2021–2040. During 2041–2070, the build-up area increased by 32.1%, the agricultural field by 36%, and the forest area decreased by 11%. Streamflow decreased significantly by 65.4 m3/yr (RCP 4.5) and 195.9 m3/yr (RCP 8.5) from 2021 to 2040. An insignificant decrease of 13.7 m3/s (RCP 4.5) and 7.63 m3/s (RCP 8.5) was observed during 2041–2070. This study provides an insight to the managers, planners, and policymakers on environmental protection/conservation for sustainable utilization of water resources at the Kibungo sub-catchment.
first_indexed 2024-04-13T13:02:11Z
format Article
id doaj.art-9b4978ee864e4ccdb2a4a375eac9761a
institution Directory Open Access Journal
issn 2405-8440
language English
last_indexed 2024-04-13T13:02:11Z
publishDate 2022-11-01
publisher Elsevier
record_format Article
series Heliyon
spelling doaj.art-9b4978ee864e4ccdb2a4a375eac9761a2022-12-22T02:45:53ZengElsevierHeliyon2405-84402022-11-01811e11285Impacts of climate and land use/cover changes on streamflow at Kibungo sub-catchment, TanzaniaLusajo Henry Mfwango0Tenalem Ayenew1Henry F. Mahoo2Africa Centre of Excellence for Water Management (ACEWM), College of Natural and Computational Sciences, Addis Ababa University, P.O. Box 1176, Ethiopia; Water Institute (W.I.), P. O. Box 35059, Dar es Salaam, Tanzania; Corresponding author.School of Earth Sciences, Addis Ababa University, P.O. Box 1176, EthiopiaDepartment of Agriculture Engineering and Land Planning, Sokoine University of Agriculture, TanzaniaThe impacts of changing climate and land use/cover on streamflow in the Kibungo sub-catchment were evaluated using the Soil and Water Assessment Tool (SWAT). Rainfall, minimum, and maximum temperature data for six stations from the ensemble mean of the RCMs (RCA4, RACMO22T, CCLM4-8-17) were used under RCP 4.5 and RCP 8.5. The homogeneity and trend test were used to detect the change point and identify the pattern in the annual time series, respectively. Land Change Modeler (LCM) was used to predict land use maps of 2040 and 2070 from historical maps. Streamflow was simulated for 2021–2040 and 2041–2070 based on the homogeneity test results. The model calibration (2009–2016) and validation (2009–2016) for streamflow were successful. The homogeneity test detects a change point in 2040. A significant decrease in annual rainfall by 22.9 mm/yr (RCP 4.5) and 57 mm/yr (RCP 8.5) for 2021–2040 and an insignificant decrease was obtained during 2041–2070 under both emission scenarios. The annual temperature increased insignificantly by 0.004 °C/yr under RCP 4.5 while a significant increase of 0.21 °C/yr under RCP 8.5 was observed for 2021–2040. For 2041–2070, a significant increase of 0.016 °C/yr (RCP 4.5) and 0.045 °C/yr (RCP 8.5) was observed. The change in land use/cover resulted in increasing the build-up area (84%), agricultural fields (55.6%), and a decrease in the forest area (10.5%) during 2021–2040. During 2041–2070, the build-up area increased by 32.1%, the agricultural field by 36%, and the forest area decreased by 11%. Streamflow decreased significantly by 65.4 m3/yr (RCP 4.5) and 195.9 m3/yr (RCP 8.5) from 2021 to 2040. An insignificant decrease of 13.7 m3/s (RCP 4.5) and 7.63 m3/s (RCP 8.5) was observed during 2041–2070. This study provides an insight to the managers, planners, and policymakers on environmental protection/conservation for sustainable utilization of water resources at the Kibungo sub-catchment.http://www.sciencedirect.com/science/article/pii/S2405844022025737Climate changeKibungo sub-catchmentLand use/cover changeStreamflow simulationSWAT model
spellingShingle Lusajo Henry Mfwango
Tenalem Ayenew
Henry F. Mahoo
Impacts of climate and land use/cover changes on streamflow at Kibungo sub-catchment, Tanzania
Heliyon
Climate change
Kibungo sub-catchment
Land use/cover change
Streamflow simulation
SWAT model
title Impacts of climate and land use/cover changes on streamflow at Kibungo sub-catchment, Tanzania
title_full Impacts of climate and land use/cover changes on streamflow at Kibungo sub-catchment, Tanzania
title_fullStr Impacts of climate and land use/cover changes on streamflow at Kibungo sub-catchment, Tanzania
title_full_unstemmed Impacts of climate and land use/cover changes on streamflow at Kibungo sub-catchment, Tanzania
title_short Impacts of climate and land use/cover changes on streamflow at Kibungo sub-catchment, Tanzania
title_sort impacts of climate and land use cover changes on streamflow at kibungo sub catchment tanzania
topic Climate change
Kibungo sub-catchment
Land use/cover change
Streamflow simulation
SWAT model
url http://www.sciencedirect.com/science/article/pii/S2405844022025737
work_keys_str_mv AT lusajohenrymfwango impactsofclimateandlandusecoverchangesonstreamflowatkibungosubcatchmenttanzania
AT tenalemayenew impactsofclimateandlandusecoverchangesonstreamflowatkibungosubcatchmenttanzania
AT henryfmahoo impactsofclimateandlandusecoverchangesonstreamflowatkibungosubcatchmenttanzania