Valley Lakes Research Articles

Surveillance on avian influenza and new castle disease in rift valley water body areas of Ethiopia

HPAI (High Pathogenic Avian Influenza) is one of the most serious public-health threats to arise from the animal reservoir. The diseases can kill up to 90% of a flock and generate epidemics that can spread quickly, wreaking havoc on the poultry business and putting severe trade restrictions in place. New Castle disease (NCD) is also a persistent threat to the poultry business and is a limiting illness for poultry farmers around the world. It is one of the most serious diseases in Ethiopia, with high mortality and huge economic losses. For this and the like purposes risk-based surveillance was conducted in selected sites in Oromia, Amhara, and Southern Nation Nationality Peoples Region (SNNPR) rift valley water body areas and 5-10 km radius districts from January to April 2019. The goal was to assess the presence or absence of Highly Pathogenic Avian Influenza (HPAI) and New Castle Disease (NCD) in migratory birds and domestic chicken in water body areas, as well as to assess the level of community awareness in the study areas. Total 6866 samples were collected, including 819 sera samples and 1836 tracheal and cloacal swab samples from backyard domestic chickens within a 5-10 km radius of rift valley lakes, and 4211 fecal droplet samples from wild/migratory birds. Avian influenza serum samples tested by HA/HI and Fecal droplet samples tested by RT PCR came back negative. The results for NDV swab 1336 samples tested by RT PCR were 182 samples positive, and 819 samples tested by HI were 72 samples positive. In the public health aspect, a questionnaire survey was completed by 180 members of the respective community. As a result, the respondents have a solid understanding of the migratory birds that visit their area.

Assessment of the combined effects of land use/land cover and climate change on soil erosion in the Sile watershed, Ethiopian Rift Valley Lakes Basin

Assessment of the combined effects of land use/land cover and climate change on soil erosion in the Sile watershed, Ethiopian Rift Valley Lakes Basin

Identifying groundwater prospect zones through earth observation techniques in Bilate watershed, Rift Valley Lakes Basin, Ethiopia

ABSTRACT Groundwater is one of the most valuable natural resources gifted to mankind, especially in surface water-scarce locations. Most parts of Ethiopia dependent on the amenity for common needs, irrigation, etc. The lack of a scientific approach to its exploitation and management makes the resource underutilized. Therefore, Remote sensing (RS) and Geographic information systems (GIS) were utilized to decipher potential groundwater zones (PGWZ) existing in the Bilate watershed of the nation to economize, speed up and technicalize the system. The ground truth of the results obtained was verified to confirm the reliability of the techniques used. Through RS, optical and microwave data were obtained, while GIS was helpful in collecting information on water points mapping and 2D resistivity survey in locating the aquifers. In particular, resistivity studies revealed both pyroclastic and rhyolite intrusions that act as water barriers and the basaltic and ignimbrite rocks that favour aquifer affluence. During the process of identification and quantification of PGWZ in the watershed, the analytical hierarchy process (AHP), weighted linear combination (WLC), and digital elevation model (DEM) were employed in thematic layer formation, reclassification, overlay analysis and map production. As a result, five PGWZ having very high (19.8%), high (35.3%), moderate (22.6%), low (19.3%), and very low (2.9%) prospects were identified. Similarly, over 75% of the area was moderate to high category in PGWZ. The accuracy of the qualitative groundwater inventory was 92.64 per cent. Thus, combining high-resolution optical/microwave data and GPS information with the AHP model has ascertained the accuracy of the PGWZ identified. So ultimately, the present work lays the foundation for the use of advanced spatial techniques in finding natural resources useful for the welfare of the nation and its populace.

Climate change potentially induces ecological change in the Ethiopian Rift Valley Lakes Basin

Streamflow regime management is critical for preserving species in riverine and riparian habitats. Quantifying flow-ecology relationships can help to characterize the effect of flow regime change on species; however, dealing with this in ungauged catchments is challenging. By regionalizing simulation of streamflow to ungauged catchments, the Indicators of Hydrological Alterations (IHA) are calculated and used as a proxy for quantifying ecological impacts. High-resolution Regional Climate Models are used to derive the future streamflow in both gauged and ungauged catchments of the Ethiopian Rift Valley Lakes Basin (RVLB). Consequently, 32 IHAs representing the magnitude, duration, frequency, rate, and timing of streamflow events during their historical and future periods are calculated. The number of cases for future IHAs deviating from their historical range is calculated, which is called the non-attainment rate of future IHAs. A threshold value for the non-attainment rate is set to classify the impact as no-impact, low, medium, or high. The non-attainment rate for the future period indicates that, high ecological impact resulted in October, which is the local high flow month. Spatially, a shift towards a later date of the Julian date indicating the maximum flow resulted in a high ecological impact. This approach can be adapted to other regions with reliable regionalization results and suitable future climate models, which would be useful for the quantification and management of ecological impacts in ungauged regions.

Twenty-Year Review of Outdoor Air Quality in Utah, USA

Air quality is a prevalent concern due to its imposing health risks. The state of Utah, USA, at times over the last 20 years has suffered from some of the worst air quality in the nation. The propensity for the state of Utah to experience elevated concentrations of particulate matter and ozone can in part be attributed to its unique geography that features dry, mountainous topography. Valleys in Utah create ideal environments for extended cold-pool events. In this review, we summarize the research executed in Utah over the past 20 years (2002–2022) by dividing the state into six regions: Utah Valley, Summit County, Southern Utah (regions south of Utah Valley), Cache Valley, Uinta Basin, and Salt Lake Valley. We review the published literature chronologically and provide a summary of each region identifying areas where additional research is warranted. We found that the research effort is weighted towards Uinta Basin and Salt Lake Valley, with the other regions in Utah only adding up to 20% of the research effort. We identified a need for more source apportionment studies, speciated volatile organic compound (VOC) studies, and ozone isopleths. Where ozone isopleths are not able to be created, measurement of glyoxal and formaldehyde concentrations could serve as surrogates for more expensive studies to inform ozone mitigation policies.

Phenotypic, molecular detection and antibiogram analysis of Aeromonas Hydrophila from Oreochromis Niloticus (Nile Tilapia) and Ready-To- eat fish products in selected Rift Valley lakes of Ethiopia

BackgroundAeromonas hydrophila is a zoonotic bacterial pathogen that frequently causes disease and mass mortalities among cultured and feral fishes worldwide. In Ethiopia, A. hydrophila outbreak was reported in Sebeta fish ponds and in Lake Tana fishery. However, there is no to little information on the molecular, and phenotypical characteristics of A. hydrophila in Ethiopian fisheries. Therefore, a cross-sectional study was conducted from November 2020 to May 2021 in selected Ethiopian Rift valley lakes.ResultsA total of 140 samples were collected aseptically from fish (Muscle, Gill, Intestine, Spleen and Kidney) from fish landing sites, market and restaurants with purposive sampling methods. Aeromonas selective media (AMB), morphological and biochemical tests were used to isolate and identify A. hydrophila. Accordingly, the pathogen was isolated from 81 (60.45%) of samples. Among the isolates 92.59% expressed virulence trait through β hemolysis on blood agar media with 5% sheep blood. Moreover, 54 strains (66.67%) were further confirmed with Real-Time PCR (qPCR) using ahaI gene specific primers and optimized protocol. The highest (68.51%) were detected from live fish, (24.07%) were from market fish and the lowest (7.4%%) were from ready-to-eat products. Antibiogram analysis was conducted on ten representative isolates. Accordingly, A. hydrophila isolates were susceptible to ciprofloxacin (100%), chloramphenicol (100%) and ceftriaxone (100%). However, all ten isolates were resistant to Amoxicillin and Penicillin.ConclusionsThe study indicates A. hydrophila strains carrying virulence ahaI gene that were ß-hemolytic and resistant to antibiotics commonly used in human and veterinary medicine are circulating in the fishery. The detection of the pathogen in 140 of the sampled fish population is alarming for potential outbreaks and zoonosis. Therefore, further molecular epidemiology of the disease should be studied to establish potential inter host transmission and antibiotic resistance traits. Therefore, raising the public awareness on risk associated with consuming undercooked or raw fish meat is pertinent.

Hydrological responses to land use and land cover change and climate dynamics in the Rift Valley Lakes Basin, Ethiopia

Abstract Due to the rapid socio-economic development in the Ethiopian Rift Valley basin, the pressures on water resources are increasing. To understand the change of spatio-temporal water fluxes, the hydrologic model SWAT+ (Soil and Water Assessment Tool+) was applied to five selected watersheds within the basin. With regards to the objective functions, Kling–Gupta efficiency (KGE: 0.68–0.84), the Nash–Sutcliffe efficiency (NSE: 0.61–0.73), percent bias (PBIAS: −3.4 to 1.4), and RMSE-observations standard deviation ratio (RSR: 0.52–0.69), the SWAT+ model performed very well for daily streamflow in all watersheds. The change in water balance components indicated a considerable spatial variation of water fluxes in the watersheds. Precipitation, evapotranspiration, and infiltration have generally decreased, but surface runoff has increased in the interference period compared to the baseline period. The spatial distribution of rainfall (−40 to 10%), evapotranspiration (−20 to 5%), surface runoff (7.8–13.1%), lateral flow (4.47 to −16.5%), and percolation (−3.3 to −10.2%) varied. The changes in the hydrologic system within the basin are greatly attributed to the combination of land use and land cover change due to rapid population growth and climate variability.

Comparison and selection criterion of missing imputation methods and quality assessment of monthly rainfall in the Central Rift Valley Lakes Basin of Ethiopia

Comparison and selection criterion of missing imputation methods and quality assessment of monthly rainfall in the Central Rift Valley Lakes Basin of Ethiopia

Limnological features and water-quality changes of two Ethiopian Rift Valley lakes, Lake Abaya and Lake Chamo

We conducted a study in Lake Abaya and Lake Chamo, the two largest Ethiopian Rift Valley lakes, between 2016 and 2019, to evaluate their limnological features and infer longer-term changes in some water-quality parameters. Data generated through in situ measurements and laboratory analyses of physico-chemical parameters and the plankton communities were compared with results from the literature. Turbidity, salinity, nitrates and soluble reactive phosphorous showed an increasing trend in Lake Abaya, while in Lake Chamo conductivity, salinity, nitrates and soluble reactive phosphorous showed an increasing trend. In both lakes the water transparency and chlorophyll a concentration showed a declining trend. Despite higher available nutrients in Lake Abaya compared with Lake Chamo, higher turbidity with suspended solids contributed to lower chlorophyll-a concentrations and lower zooplankton abundance. The abundances of rotifers and crustaceans were lower in Lake Abaya compared with Lake Chamo. The mean trophic state index using total phosphorus, Secchi depth and chlorophyll-a shows that both lakes are in a eutrophic state. Our findings are consistent with previous studies and indicate that changes in major limnological features are a signal to take intervention measures to prevent further ecological degradation and to sustain the ecological services and livelihoods of fishers who are directly dependent on the lakes.

First <sup>10</sup>Be dates of Late Holocene moraines of the Kashkatash and Irik glaciers, Northern Caucasus

We present 11 10Be ages of the moraines of the Irik and Kashkatash glaciers that allowed identifying and dating several Late Holocene glacier advances for the first time, including a prominent advance exceeding the Little Ice Age (LIA) maximum that occurred at 1.6–1.7 ka at еру Irik Glacier. The advance is dated by the three very close 10Be ages of a moraine (1.57 ± 0.23 ka, 1.63 ± 0.23, and 1.68 ± 0.24 ka) located in the vicinity of the moraines of the Little Ice Age (LIA) maximum advance. The advance that occurred at 1.6–1.7 ka might be a possible analogue of the “Historical” stage described earlier in the Caucasus in literature basing at geomorphic evidence, speculations, and analogues with other mountain regions, but not dated. Another possibility is a potential correlation of this advance with the Late Antique Little Ice Age cooling in 536 to ~660 CE. The age of Irik Glacier advance is close to the humid period identified in the Garabashi (Baksan, Elbrus valley) lake sediments at 1500–1700 years BP. The magnitude of the identified glacier advances over the past two millennia was similar. Between the advance of 1.6–1.7 ka and the position of the glacier in 2022 CE the elevation of the Irik Glacier front increased by 520 m from 2490 to 3010 m asl. Four 10Be dates (0.7 + 0.11, 0.72+0.11, 0.77 + 0.11 and 0.82 + 0.18 ka) of the lateral moraine of the Kashkatash Glacier constrain the advance of the first stage of the LIA. The advance of the 13th century is also dated by 10Be at the Donguz-Orun and Chalaati glaciers located at the Northern and Southern slopes of the Caucasus, respectively. The corresponding cooling in ca 1250–1400 CE is identified in the sedimentary paleoclimatic proxies of Lake Karakel (Teberda valley). A later advance at the Kashkatash Glacier is constrained by only one 10Be date (0.53± 0.13 ka) and needs further confirmation. Till deposited between the 1490s and 1640s at the Greater Azau Glacier is close to the date of this advance of the Kashkatash Glacier. A cooling at that time is recorded in the proxies of Karakel Lake sediments (1500–1630 CE). Three other 10Be dates of two earlier advances at 0.25 + 0.04 ka and between 0.14 + 0.03 and 0.16 ± 0.02 ka at Kashkatash Glacier are indirectly supported by tree-ring, lake sediment, 14C, and historical data. Further research and new data is necessary to increase the credibility and accuracy of the dates of glacier advances of the Late Holocene in the Northern Caucasus.

Modelling the current status of Lake Malawi fish stocks, an inland lake in East Africa

Abstract Inland rift valley lake systems have been sustaining humanity for a long time. Only recently have commercial fisheries entered these systems and for Lake Malawi, this occurred in the mid-1970s upon successful experimental trawl fishing. Lake Malawi with the highest diversity of freshwater fishes in the world has had fisheries for centuries. Previous assessment of the impact of commercial trawl fisheries revealed significant changes in stock composition and overall biomass. The study evaluates the state of fisheries resources using novel techniques developed using integrated assessment methods amenable to data poor fisheries. Data from biomass assessment surveys and landed catch from 2016 to 2019 were examined to determine the status of selected fish stocks over time. Stock Synthesis for Data Limited tools in R environment were used to run the models. The Surplus Production Models and Statistical catch-at-age models that were used to examine alternative hypotheses on life history parameters on the key stocks exploited primarily by the commercial trawl fishery and evaluate long-term trends on these populations. The study results revealed that Mcheni (Rhamphochromis spp.), Ndunduma (Diplotaxodon limnothrissa) and Utaka (Copadichromis virginalis) stocks are within the sustainable limits, while Chambo (Oreochromis karongae), Chisawasawa (Lethrinops gossei), Mlamba (Bathyclarias nyasensis) and Kampango (Bagrus meridionalis) appear to be overfished in recent years, though Kampango may have recovered recently. Given, the large uncertainties with productivity of most tropical fishes with climate change, as well as large uncertainties due to inaccurate and untimely data submissions, it is recommended that a systematic monitoring and evaluation program, like the one being conducted in Lake Malawi should be developed for other inland lake systems. If stocks are facing overfishing by both the small-scale and commercial trawl fisheries, limits to overall catch and size should be implemented possibly through output controls such that the fisheries remain sustainable for the long term.

Performance evaluation of multiple regional climate models to simulate rainfall in the Central Rift Valley Lakes Basin of Ethiopia and their selection criteria for the best climate model.

The historical datasets of five regional climate models (RCMs) available in the Coordinated Regional Downscaling Experiment (CORDEX)-Africa database are evaluated against ground-based observed rainfall in the Central Rift Valley Lakes Basin of Ethiopia. The evaluation is aimed at determining how well the RCMs reproduce monthly, seasonal, and annual cycles of rainfall and quantify the uncertainty between the RCMs in downscaling the same global climate model outputs. Root mean square, bias, and correlation coefficient are used to evaluate the ability of the RCM output. The multicriteria decision method of compromise programming was used to choose the best climate models for the climate condition of the Central Rift Valley Lakes subbasin. The Rossby Center Regional Atmospheric Model (RCA4) has downscaled ten global climate models (GCMs) and reproduces the monthly rainfall with a complex spatial distribution of bias and root mean square errors. The monthly bias varies in the range of - 35.8 to 189%. The summer (wet), spring, winter (dry), and annual rainfall varied within the range of 1.44 to 23.66%, - 7.08 to 20.04%, - 7.35 to 57%, and - 3.11 to 16.5%, respectively. To find the source of uncertainty, the same GCMs but downscaled by different RCMs were analyzed. The test results showed that each RCM differently downscaled the same GCM, and there was no single RCM model that consistently simulated the climate conditions over the stations in the study regions. However, the evaluation finds reasonable model skill in representing the temporal cycles of rainfall and suggests the use of RCMs where climate data is scarce after bias correction.

Can We Detect Urban‐Scale CO2 Emission Changes Within Medium‐Sized Cities?

AbstractThe COVID‐19 pandemic resulted in a widespread lockdown during the spring of 2020. Measurements collected on a light rail system in the Salt Lake Valley (SLV), combined with observations from the Utah Urban Carbon Dioxide Network observed a notable decrease in urban CO2 concentrations during the spring of 2020 relative to previous years. These decreases coincided with a ∼30% reduction in average traffic volume. CO2 measurements across the SLV were used within a Bayesian inverse model to spatially allocate anthropogenic emission reductions for the first COVID‐19 lockdown. The inverse model was first used to constrain anthropogenic emissions for the previous year (2019) to provide the best possible estimate of emissions for 2020, before accounting for emission reductions observed during the COVID‐19 lockdown. The posterior emissions for 2019 were then used as the prior emission estimate for the 2020 COVID‐19 lockdown analysis. Results from the inverse analysis suggest that the SLV observed a 20% decrease in afternoon CO2 emissions from March to April 2020 (−90.5 tC hr−1). The largest reductions in CO2 emissions were centered over the northern part of the valley (downtown Salt Lake City), near major roadways, and potentially at industrial point sources. These results demonstrate that CO2 monitoring networks can track reductions in CO2 emissions even in medium‐sized cities like Salt Lake City.

Change at 85 degrees south: Shackleton Glacier region proglacial lakes from 1960 to 2020

Abstract Over the last two decades, anomalous warming events have been observed in coastal Antarctic regions. While these events have been documented in the Ross Sea sector, the Antarctic interior is believed to have been buffered from warming. In this work, we present data from lakes located near Mt. Heekin and Thanksgiving Valley (~85° S) along the Shackleton Glacier, which are believed to be the southern-most Antarctic dry valley lakes. In 2018, the lakes were characterized, repeat satellite images were examined, and lake water chemistry was measured. Our analysis shows that lake areas recently increased, and the water-soluble ion chemistry indicates a flushing of salts from periglacial soils, likely from increased glacial melt as illustrated by water isotope data. Our results show that high southern latitude ice-free areas have likely been affected by warm pulses over the past 60 years and these pulses may be quasi-synchronous throughout the Transantarctic Mountains.

Study on the Early Cretaceous fluvial-desert sedimentary paleogeography in the Northwest of Ordos Basin

Abstract Early Cretaceous desert sedimentary system was developed in Northwest Ordos Basin. At present, the research degree of desert sedimentary paleogeography is low. The research on paleogeographic environment of Early Cretaceous sedimentary sandstone has guiding significance for the exploration of uranium resource and underground water resource in Northwest Ordos Basin. Based on the previous basic geological data of the lower Cretaceous in the Northwest of Ordos, through field geological survey, drilling core observation, and paleocurrent measurement, the sedimentary paleogeographic environments in different periods of Early Cretaceous had been studied. The results show that the lower Cretaceous in Northwestern Ordos Basin can be divided into two sedimentary cycles, the lower sedimentary cycle composed of Luohe Formation and Huachi-Huanhe Formation, and the upper sedimentary cycle composed of Luohandong Formation and Jingchuan Formation. Alluvial, Aeolian, and desert lake depositional systems were developed. The main sedimentary facies were alluvial fan, braided river, sand dune, dry valley, and dry lake. Alluvial fan and braided river facies had mainly developed in Luohe Formation. Braided fluvial facies mainly had developed in Huachi-Huanhe Formation, and alluvial fans locally developed around it. The deposits in Luohandong Formation were mainly aeolian sandstone, and the alluvial fan facies were inherently developed at Western and Northern margins. The depositional environment of Jingchuan formation is mainly river and lake. The tectonic evolution of lower Cretaceous had controlled the development of paleogeographic environment, and sedimentary facies had controlled the development of aquifer system. The paleogeographic environment of Early Cretaceous is conducive to the reduction and enrichment of uranium and the development of metallogenic units.

Assessing the impact of climate change on the hydrology of Gidabo river sub-basin, Ethiopian Rift Valley Lakes Basin

Assessing the impact of climate change on the hydrology of Gidabo river sub-basin, Ethiopian Rift Valley Lakes Basin

Utah's Women Homesteaders

Utah's Women Homesteaders

Consumer health risk assessment from some heavy metal bioaccumulation in common carp (Cyprinus carpio) from lake Koka, Ethiopia

Heavy metal pollution is a serious problem in Ethiopian rift valley lakes, including Lake Koka, as a result of unmanaged industrial waste pollution. However, the bioaccumulation level in common carp (Cyprinus carpio), a commercially important fish species, are unknown. The aim of this research was, therefore, to assess the heavy metal bioaccumulation in edible parts of common carp in Lake Koka and the associated health risks. Three sampling sites were selected randomly for primary data collection. Four heavy metals (Cd, Cr, Pb and Zn) were analyzed in water and the edible part of the fish using Atomic Absorption Spectroscopy (AAS). The mean concentrations of Zn, Cr and Cd in the edible part of fish ranged from 0.07 to 0.36 mg kg−1, Not Detected (ND)-0.24 mg kg−1 and ND-0.03 mg kg−1, respectively. Site 2 had the highest Zn and Cd content, while Site 3 had the highest Cr content. Pb was however not identified. The amount of Cr was above the permissible limit of FAO and the bioaccumulation showed marked differences among the sampling sites (p < 0.05). The concentrations of Cd, Pb and were below the maximum permissible limit. Cr and Zn had the highest and lowest transfer factor values, respectively. The carcinogenic hazard ratio values were below the threshold value (<1). The estimated weekly intake of heavy metals from fish muscles ranked as Cr > Zn > Cd, but the values were lower than the Reference Dose limit (RfDo). The carcinogenic risk value also indicated a low health risk associated with individual metals intake. Furthermore, the hazard index of the edible part of fish was less than unity. Generally, the water quality is not a risk for the survival and reproduction of fish and the heavy metal contents in the edible parts of fish exhibited low carcinogenic risk through the food chain.

Review: Groundwater research in the Ethiopian Rift Valley Lakes region

Despite its proximity to many research institutions in the country and prevailing environmental and water security challenges, water resources research in the Central Rift Valley of Ethiopia has few decades of history. Research undertaken so far, mainly focus on the lakes' environment and anthropogenic activities in their proximities. Worsening deterioration of the water resources and environmental conditions; and the need to address overlooked but determinant natural and anthropogenic processes spurred a critical review of what has been done so far. This work provides an overview of the history of water research in the central rift valley and tries to reveal research gaps related to surface water-groundwater interaction, water quality, and changing trends in the hydro ecosystem and possible causes. Apart from this, articles dealing with the geological and structural setup of the central rift valley were systematically reviewed to show their control over the hydrologic system. The review work has revealed that although the current state of the central rift valley is a product of anthropogenic and geogenic processes; which are happening within the sub-basin and its adjacent basins that need to be addressed at a higher thematic, spatial, and temporal scopes, there is gap in reviewed research, to address the issue at this level. The forefront environmental challenges and the need for quick fixes, lack of data, and funding are found to be some of the reasons to limit the scope of research activities, mainly to shallow groundwater zones and surface hydrological processes around the lakes. This approach has hindered seeing the bigger picture and resulted in ineffective environmental and natural resources restoration measures and policy decisions.

Groundwater Recharge Estimation in Upper Gelana Watershed, South-Western Main Ethiopian Rift Valley

Estimating the spatial and temporal patterns of groundwater recharge through integrated water balance modeling plays an important role in sustainable groundwater resource management. Such modeling effort is particularly essential for data-scarce regions, such as the Rift Valley Lake basin in the Basement Complex of Ethiopia, which has shallow aquifers, a proliferation of wells, and poor groundwater monitoring networks. A spatially distributed water balance model (WetSpass), along with GIS and remote sensing tools, was used for groundwater recharge estimation for its suitability and efficiency in data-scarce hydrogeological regions. The WetSpass model depicted a very good performance in simulating the groundwater recharge in the Upper Gelana watershed within the Rift Valley Lake basin. The water balance analysis revealed that about 7% of the mean annual rainfall is converted to groundwater recharge, and the remaining rainfall amounts are partitioned into surface runoff (19%) and evapotranspiration (75%). The model simulation outputs are also used to investigate the relative influences of biophysical driving factors on the water balance components. While the land use types had a greater influence on the actual evapotranspiration processes, the soil texture classes were the dominant factors in the surface runoff and groundwater recharge processes in the watershed. The groundwater recharge rates were found to be higher than 400 mm/yr in the central parts (Fisehagenent, Tore, and Gedeb) and lower than 165 mm/yr in the southern parts (Hageremariam) of the watershed. The areal proportions of the low, medium, and high recharging parts of the watershed are, respectively, estimated as 15%, 68%, and 17% of the watershed area. Therefore, the spatial and temporal patterns of groundwater recharge should be taken into consideration in developing a sustainable groundwater resources management plan for the Upper Gelana watershed. Managed aquifer recharge can be adopted in high and medium groundwater recharging parts of the watershed to capture stormwater runoff during the wet season to improve the groundwater supply during dry months. Furthermore, monthly groundwater withdrawals should be regulated according to the spatial and temporal patterns of the groundwater recharge in the watershed.