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Understanding the land use land cover dynamics and its drivers is essential to generate evidences for making appropriate interventions to safeguard the environment. The study assesses the impacts of resettlement on the Land use land cover (LULC) change in Nensebo district of Ethiopia using remote sensing and in situe field surveys over a period of 33 years (1986–2019). Four years' temporal satellite images 1986, 2000, 2011 and 2019 were used to assess the LULCC. Supervised maximum likelihood classification algorithm was used to classify the images. A multi-stage sampling procedure was used to select the study district, three kebeles and respondents. From a total of 987 households, 285(29%) household heads were selected using simple random sampling. Questionnaire survey, key informant interviews, and focus group discussions were employed to address the drivers. The result showed that there was a rise of farmland from 9.27% in 1986 to 31.55% in 2019 with a rate of 7.30% per annum. Conversely, forest cover was shrinking from 84.40% in 1986 to 57.87% in 2019 with a rate of 0.95% per annum. The study also revealed a significant conversion of shrubland and forest cover to farmland with 58.2% and 29% respectively over the study period. The study revealed that the rapid rate of deforestation and LULCC were attributed to proximate drivers (commercial farmland expansion, resettlement, forest fire, population growth, illegal logging, charcoal and firewood production) and underlying causes (population pressure, poverty, land scarcity, and weak law enforcement). Thus, making appropriate interventions aimed at ensuring sustainability of environments by protecting forests and grasslands and minimizing livelihood dependence on the environmental resources is necessary. [ABSTRACT FROM AUTHOR]

Understanding the hydrological process associated with Land Use/Land Cover (LU/LC) change is vital for decision-makers in improving human wellbeing. LU/LC change significantly affects the hydrology of the landscape, caused by anthropogenic activities. The scope of this study is to investigate the impact of LU/LC change on the hydrological process of Upper Baro Basin for the years 1987, 2002, and 2017. The Soil Water Assessment Tool (SWAT) model was used for the simulation of the streamflow. The required data for the SWAT model are soils obtained from the Food and Agriculture Organization; Digital Elevation Model (DEM) and LU/LC were obtained from the United States Geological Survey (USGS). The meteorological data such as Rainfall, Temperature, Sunshine, Humidity, and Wind Speeds were obtained from the Ethiopian National Meteorological Agency. Data on discharge were obtained from Ministry of Water, Irrigation and Electricity. Ecosystems are deemed vital. Landsat images were used to classify the LU/LC pattern using ERDAS Imagine 2014 software and the LU/LC were classified using the Maximum Likelihood Algorithm of Supervised Classification. The Sequential Uncertainty Fitting (SUFI-2) global sensitivity method within SWAT Calibration and Uncertainty Procedures (SWAT-CUP) was used to identify the most sensitive streamflow parameters. The calibration was carried out using observed streamflow data from 01 January 1990 to 31 December 2002 and a validation period from 01 January 2003 to 31 December 2009. LU/LC analysis shows that there was a drastic decrease of grassland by 15.64% and shrubland by 9.56% while an increase of agricultural land and settlement by 18.01% and 13.01%, respectively, for 30 years. The evaluation of the SWAT model presented that the annual surface runoff increased by 43.53 mm, groundwater flow declined by 27.58 mm, and lateral flow declined by 5.63 mm. The model results showed that the streamflow characteristics changed due to the LU/LC change during the study periods 1987–2017 such as change of flood frequency, increased peak flows, base flow, soil erosion, and annual mean discharge. Curve number, an available water capacity of the soil layer, and soil evaporation composition factor were the most sensitive parameters identified for the streamflow. Both the calibration and validation results disclosed a good agreement between measured and simulated streamflow. The performance of the model statistical test shows the coefficient of determination (R2) and Nash–Sutcliffe (NS) efficiency values 0.87 and 0.81 for calibration periods of 1990–2002 and 0.84 and 0.76 for the validation period of 2003 to 2009, respectively. Overall, LU/LC significantly affected the hydrological condition of the watershed. Therefore, different conservation strategies to maintain the stability and resilience of the ecosystem are vital. [ABSTRACT FROM AUTHOR]

We conducted a quantitative assessment of forage biomass in Harshin district to determine its annual productive potential, carrying capacity, and stocking rates. The dominant Land Use and Land Cover include woodland (35.5%), shrubs (28.3%), grassland (10.6%), and bare land (25.5%). The region has browse‐rich shrubland that is edible to dromedary and goats, as well as massive grassland plains for sheep and cattle. The interannual rainfall variation is 16.5% which implies that the rangeland is a subsistence equilibrium system. The range of forage production is between 105 and 2,310 kg/ha, whereas the average productivity of the district is 742.6 kg/ha. The result indicates that the average carrying capacity of the district is 0.3 TLU ha−1 year−1 (4.9 ha TLU−1 year−1) while the existing stocking rate is 5.4 TLU ha−1 year−1 (0.18 ha TLU−1 year−1). This implies that the grazing intensity in the district is much higher than its carrying capacity (recommended rate), which has seen overstocking or grazing pressure excesses of 5.1 TLU/ha (7.2 cattle/ha). Thus, it clearly signals the risk of overgrazing in the district. If this trend continues, the grazing will not be sustainable and there will be shortage of forage as well as expansion of land degradation (due to overgrazing) in the near future. [ABSTRACT FROM AUTHOR]

Abstract The impact of land use/land cover and climate change on the hydrology are global issues affecting the whole catchment of the river basin. The main objective of this study was to investigate runoff response to land use/land cover change in Aynalem catchment, located in Tigray regional state, northern Ethiopia. The study analyzed the historical land cover changes from 1995 to 2015 that have taken place in the catchment and its effect on the runoff of the catchment. The land cover changes within the catchment were examined through classification of satellite images with integrated use of ERDAS Imagine (Version 9.2) and ArcGIS software. Land cover change analysis between the periods of 1995 and 2015 has shown that the urban area has increased from 1.39% to 7.50%, Cropland from 54.03% to 65.69% and Water bodies from 0.14% to 0.42%, while Planted Forest area has decreased from 3.61% to 2.92%, Grassland 2.22%–1.90% and Open Shrub lands from 38.61% to 21.53%. Further, Water and Energy Transfer between Soil, Plants, and Atmosphere (WetSpa) model was used to investigate the runoff response to a land cover change on the study area. The model was calibrated (1994–1998) and validated (1999–2001) against the observed daily stream flow data. WetSpa model parameters sensitivity analysis result shown that the groundwater recession coefficient (Kg), Initial active groundwater storage (Go) and Surface runoff exponent (K_run) are the most sensitive parameters affecting the hydrology of the catchment. The WetSpa model application in Aynalem catchment performances very good in reproducing the hydrological process of the catchment with coefficient of determination (R2), Nash and Sutcliff efficiency (NSE) values of 0.82 and 0.90 for calibration, 0.78 and 0.88 for validation, respectively. The WetSpa model application with land useland cover maps of 1995, 2003 and 2015 shows annual runoff increased by 21.1% from the year of 1995–2003 and 23.5% from 2003 to 2015 and also, 44.6% from 1995 to 2015. The increment in runoff is likely to have been caused by the change of the land use/land cover from shrubs and grass lands to urban and cultivated lands. Highlights • Built-up area and cropland increased on the expense of planted forest and grassland. • WetSpa model performed well and can be used for runoff estimation in the catchment. • Annual surface runoff increased in response to land use/landcover changes. [ABSTRACT FROM AUTHOR]

This study analyzes the impact of land use/land cover (LULC) changes on the hydrology of the dry Afromontane forest landscape in northern Ethiopia. Landsat satellite images of thematic mapper (TM) (1986), TM (2001), and Operational Land Imager (OLI) (2018) were employed to assess LULC. All of the images were classified while using the maximum likelihood image classification technique, and the changes were assessed by post-classification comparison. Seven LULC classes were defined with an overall accuracy 83–90% and a Kappa coefficient of 0.82–0.92. The classification result for 1986 revealed dominance of shrublands (48.5%), followed by cultivated land (42%). Between 1986 and 2018, cultivated land became the dominant (39.6%) LULC type, accompanied by a decrease in shrubland to 32.2%, as well as increases in forestland (from 4.8% to 21.4%) and bare land (from 0% to 0.96%). The soil conservation systems curve number model (SCS-CN) was consequently employed to simulate forest hydrological response to climatic variations and land-cover changes during three selected years. The observed changes in direct surface runoff, the runoff coefficient, and storage capacity of the soil were partially linked to the changes in LULC that were associated with expanding bare land and built-up areas. This change in land use aggravates the runoff potential of the study area by 31.6 mm per year on average. Runoff coefficients ranged from 25.3% to 47.2% with varied storm rainfall intensities of 26.1–45.4 mm/ha. The temporal variability of climate change and potential evapotranspiration increased by 1% during 1981–2018. The observed rainfall and modelled runoff showed a strong positive correlation (R2 = 0.78; p < 0.001). Regression analysis between runoff and rainfall intensity indicates their high and significant correlation (R2 = 0.89; p < 0.0001). Changes were also common along the slope gradient and agro-ecological zones at varying proportions. The observed changes in land degradation and surface runoff are highly linked to the change in LULC. Further study is suggested on climate scenario-based modeling of hydrological processes that are related to land use changes to understand the hydrological variability of the dry Afromontane forest ecosystems. [ABSTRACT FROM AUTHOR]