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Climate variability significantly affects the overall agricultural production and productivity over space and time. To quantify the effect of climate variability on natural systems on Earth in the future, the use of regional climate models (RCMs) as a tool is mandatory. Thus, the use of well-validated RCM provides efficient climate data, and predicts future climate variability over agroecological zones (AEZs). Eleven RCMs from CORDEX-Ethiopia were evaluated to simulate maximum temperature (Tmax), minimum temperature (Tmin) and rainfall variability over space and time, to validate their performance and to select the best-fit models. The temporal variability Tmax and rainfall was smaller with a CV of 10 %, indicating uniform distribution over stations. However, CV for Tmin over stations shows satisfactory distributions. Most of the evaluated RCMs have a better capability to capture the spatial variability of rainfall,Tmax, and Tmin in some stations. However, some of the RCMs can handle the spatial variability of Tmax while others are not. None of the RCMs can handle the spatial variability of Tmin in Debre Birhan, Majete, and Kewat AEZs. In general, most RCMs can capture the spatial and temporal variability of rainfall and temperature. It might be better to use the ensemble average of the output from these RCMs for precise estimation of data than specific RCMs. Therefore, this work could suggest the use of high-resolution RCMs for the projection of temperature and rainfall over different AEZs.

Abstract This study examined the impact of climate change on streamflow in the Andit Tid watershed using climate models of dynamically downscaled Ethiopia’s CORDEX. The Arc SWAT and ArcGIS 10.5 software assessed the spatial and temporal distribution of streamflow, incorporating geospatial data like land use maps, digital elevation models, soil maps, and climate data. The SWAT model was calibrated and validated using SWAT-CUP with the SUFI-2 algorithm. The Canadian Centre for Climate Modeling and Analysis, Canada (CCCma (RCA4) model was selected for future projections after validation. From 1991 to 2021, the average streamflow rate was 0.0374 m3/s (247 mm), with R2 values of 0.83 for calibration and 0.72 for validation. Hotspots with active gullies and slopes over 20% were identified mainly in cultivated lands. Future projections indicated a comparable streamflow rate to current conditions at 0.0322 m3/s (212.6 mm). A decline in streamflow is projected: 7.2% and 30.2% decreases in the near and far future under RCP 4.5, and 32.3% decreases and 5% increases under RCP 8.5 scenarios. These variations were attributed to differences in catchment characteristics and climate variability. Further research is needed to validate these findings by incorporating additional biophysical variables. This study provides insights into hydrological planning and management in the Andit Tid watershed and similar regions facing climate variability.

The study utilized the Modified Universal Soil Loss Equation (MUSLE) to predict sediment loss and evaluate the model's performance in the Agewmariam experimental watershed in order to support the planning, management, and appropriate use of the soil and water resources in the watershed. The natural resources conservation service (NRCS) curve number method was used to model runoff energy factor. By overlaying maps of runoff energy, soil erodibility, slope length and steepness, cover management, and support practice factors with assigned values, the cumulative effect of these parameters for the suspended sediment yield was calculated using the ArcGIS raster calculator. The runoff energy factor was the most sensitive parameter, followed by slope length and steepness factor. To improve the model's fit to the local conditions, the initial abstraction to storage ratio (λ) of the runoff energy factor was reduced to 0.023, and the MUSLE model coefficient and exponent were adjusted to 1 and 0.59, respectively. During calibration, the mean observed and estimated suspended sediment yields were 0.2 and 0.23 ton/ha, respectively, while during validation, they were 0.7 and 0.53 ton/ha, respectively. The model evaluation showed that the MUSLE model, without calibration, was not appropriate for estimating runoff and sediment yield. However, with appropriate calibration, the model showed good performance with a coefficient of determination (R2), coefficient of efficiency (E), and index of agreement (d) of 0.85, 0.85, and 0.96 respectively, during calibration and 0.84, 0.65, and 0.83 respectively, during validation. Based on these findings, this study suggests that the calibrated MUSLE model can be used to prioritize soil and water conservation interventions within the watershed or can be extrapolated to neighboring similar watersheds. Further refinement of model input parameters using more data from the watershed is recommended to increase the prediction accuracy of the model.

Soil erosion, land degradation and climate change are the major environmental threats attributed to low agricultural productivity in Ethiopia. To reduce soil erosion and restore degraded lands, integrated soil and water conservation interventions have been implemented. However, the impacts of the intervention measures were not sufficiently studied due to the lack of baseline information. Therefore, this study was carried out to evaluate and understand the current conditions of biophysical resources in Ferenjua watershed, which is located in Gondar zuria district. In this study, more emphasis was given to the levels of total nitrogen (TN), available phosphorous (P), organic matter (OM), bulk density (BD), pH, moisture, texture and soil erosion. To collect the biophysical data, the watershed was divided into 144 grid-based sampling points with a resolution of 250 m by 250 m. In addition, the data were collected in 8 representative profile pits. Three primary land uses were identified from supervised land use and land cover classification and described as cultivated land (55.08 %), forestland (30.80 %), and grassland (14.12 %). Erosion hotspot map shows that >40 % of the watershed is moderately and highly susceptible to soil erosion. The highest BD (1.36 gm cm−3) was observed at Vertisols-dominated cultivated lands located in the flatlands, whereas, the lowest BD (1.28 gm cm−3) was observed under forestland. Regarding the results of TN, P, and OM, >60 % of the watershed was classified as having low to very low soil nutrient levels. Consequently, development interventions should be considered to restore degraded lands for the sustained use of resources in the watershed.

The Soil and Water Assessment Tool (SWAT) and the Geographic Water Erosion Prediction Project (Geo-WEPP) were applied to compare modeling of annual runoff and sediment yield in the Agewmariam watershed, eastern Amhara Region, Ethiopia. Spatial and temporal data distributions were required as inputs to run both models. Soil texture and other soil properties were measured in the field and in the laboratory, and soil maps were generated from global digital soil maps. Land use maps were created by manually digitizing Google Earth images. Watersheds were defined using watershed DEMs and gradient maps were created for each runoff event. Runoff samples were collected and analyzed for sediment concentrations in the laboratory; average annual runoff and sediment volumes were estimated using the WEPP and SWAT models. The results were satisfactory compared to the observed values, with R2 values of 0.86 and 0.91 for the SWAT and WEPP models, respectively, and NSE values of 0.54 and 0.71 for the monthly runoff. The estimated annual mean runoff and sediment yield at the watershed outlets were 65.54 mm, 146.14 mm, 43t/ha/yr and 41.7t/ha/yr for the WEPP and SWAT models, respectively. Several sub watersheds were determined to be susceptible to soil erosion and were prioritized, so more attention was given to this area to reduce runoff and soil erosion. Therefore, the SWAT and WEPP models were suitable for estimating annual runoff and sediment volumes. Sediment yields simulated from both models were high and alarming and far exceeded the allowable rate of soil loss.

Climate change coupled with inappropriate land use management is a serious environmental challenge in the highland part of Ethiopia. The aim of this study was to investigate hydro-sediment responses to management options under current and future climate change scenarios in Maybar watershed, Northern Ethiopia. We employed soil and water assessment tool (ArcSWAT 2012.10_7.24) for hydrologic modeling and CORDEX-climate data under RCP 4.5 and RCP 8.5 emission scenarios for climate projections. Soil map was prepared by digitizing soil characterization map of the watershed generated by Weigel in 1986. DEM data with 2 m spatial resolution was obtained from water and land resource center and land use classification was done through digitization of google earth images. Better agreement between calibrated SWAT simulation and observed variables was achieved. Delta change bias correction method was employed to improve the climate simulation in reproducing the observed climate variables. We found a considerable increase in annual precipitation by 18.71 % and 22.33 % for RCP 4.5 and RCP 8.5, respectively compared with the current climate conditions. Climate change induced hydro-sediment results were observed to be consistent with predicted precipitation. Under the current climatic conditions, average sediment yield at the sub-basin scale varies from negligible (under terrace complementation) to approximately more than 50 t ha−1 yr−1 with a basin average of 32 t ha−1 yr−1 (under no-terrace conditions). The implementation of management alternatives gets the dry season's hydrological behavior of the catchment improved and climate change induced sediment yield reduction. Generally, the information could possibly support decision makers and planners to implement best-fitted management options and thereby reduce current and expected aggressive sediment loss situations.

Abstract Soil acidity has become a serious problem in the northern highlands of Ethiopia, limiting land productivity mainly that of crop yield. Research had been done to try to come up with results showing the area was affected by severe acidity, but based on few watersheds and districts in a haphazard way. The objective of this research was therefore to develop a comprehensive soil pH map that covers a broader area of 27 districts covering 2,810,055 ha of land to assess the degree of soil acidity in the Tana Sub‐basin, northwestern highlands of Ethiopia. Using GPS (3‐m precision), 2652 soil point data were collected. Precipitation, elevation, and land use cover were taken into account when creating an interpolated soil pH map. Using adjacent probed pH values, ordinary kriging interpolation (R2 = 0.65; root‐mean‐square error = 0.37125) technique was used to estimate the unmeasured locations, while the spatial pH variability was mapped using the geostatistical (GS+10) software. All Food and Agriculture Organization of the United Nations soil pH categories, with 11.22%, 19.97%, 18.77%, 14.59%, 9.64%, and 6.29% of the soil samples being extremely acidic, strongly acidic, moderately acidic, slightly acidic, neutral, moderately alkaline and strongly alkaline, respectively, were observed. The interpolation result showed a moderate coefficient of variation (10.52%) indicating that the research area had medium variability. In addition, the nugget‐to‐total semivariance ratio ranged from 25% to 75%, indicating moderate geographic dependence. The pH semivariograms best fitted the exponential model, which means the one with maximum (R2 = 0.834) and with minimum residual sum of squares (1.819E‐06) value for mapping of pH. Our result showed that soil pH was inversely dependent on precipitation and altitude, while it varies with land use type. The research result/map could give useful tools for effective integrated land management to minimize soil acidification by policymakers, agriculturalists, and other stakeholder groups. We also recommended future routine updates on the size and distribution of surface soil acidity in the study area.

Vertisols are crucial for improving and sustaining food production in Ethiopia. However, due to conventional tillage and waterlogging, the great potential of Vertisols in the study area has been underutilized. Different tillage practices combined with planting techniques play a significant positive role in improving crop yield in high-rainfall areas. This study was conducted to evaluate the effects of tillage practices and planting techniques on the productivity of sesame and sorghum in Metema experimental site, in northwestern lowlands of Ethiopia. The experiment was conducted with three replications and six treatments described as: permanent raised bed with minimum tillage (PRB + MT), permanent raised bed with minimum tillage, and mulch (PRB + MT + M), broad bed furrow (BBF), flatbed with minimum tillage and mulch (Flat + MT + M), flatbed with minimum tillage (Flat + MT) and control. The results indicated that the soil moisture content was significantly higher in control (40.77–43.56 %) and flatbeds compared with BBF (39.30–40.39 %) and PRB + MT + M treatments. The bulk density of the soil and organic carbon levels showed significant variations between treatments. The highest bulk density was observed in the control (1.29 Mg m−3) than in PRB + MT (1.12 Mg m−3). In this regard, the highest seed yield of sesame (1138.52 kg ha−1) and grain yield of sorghum (5456.90 kg ha−1) were obtained from BBF and PRB + MT + M respectively. Inversely, the lowest seed yield of sesame (778.77 kg ha−1) and grain yield of sorghum (4052.7 kg ha−1) were obtained from the control plot. Therefore, to improve the productivity of sesame and sorghum, the preparation of BBF and PRB + MT + M should be taken into account.

The analysis of the spatial interrelationship between soil properties and slope aspect is vital for understanding the range of influence on soil depth, moisture, and stone content distribution. This study aimed to investigate the spatial interrelationship of topsoil moisture and stone content in different slope aspects and soil depth. The 53.7 km2 watershed was divided into a 500m by 500m grid using ArcGIS and 230 soil samples were collected. In each sampling point, the soil was taken at three soil depth classes (0–25cm, 25–60cm, and 60–100cm) using a cylindrical auger, then soil samples were tested to determine the percentage of topsoil moisture, and stone content. The spatial interrelationship between aspect, soil depth, topsoil moisture, and stone content was analyzed using the R and GS+ software. The study had shown non-significant effects of aspect on topsoil moisture, stone content, and soil depth. However, topsoil moisture tends to be higher on the north-facing slope, while stone content tends to be higher on the southeast-facing slope. The analysis of Local Moran’s I revealed that topsoil moisture, stone content, and soil depth were significantly autocorrelated. The cross-semivariogram analysis of soil depth with topsoil stone content depicted a negative spatial correlation. The experimental cross-semivariogram of soil depth versus topsoil moisture was positively fitted to the exponential function, whereas soil depth with topsoil stone content was best fitted to the Gaussian model. Overall, soil depth is the more influential factor than the slope aspect regarding topsoil moisture depletion and stone content distribution in the study watershed.

Various soil and water conservation (SWC) practices have been constructed through campaign-based integrated watershed management in Ethiopia since 2011. However, not all SWC measures were implemented across the country and preferred by the farmers equally. Hence, this research aimed to evaluate the trends of community-mobilized SWC practice and farmers’ SWC preference to combat land degradation in Amhara region, Ethiopia. The study utilized primary and secondary data from 92 selected watersheds across 13 zones, 45 woredas, and 1,739 households. Extensive household interviews that include elders, women, and youth, as well as focus group discussions and key informant interviews were conducted and analyzed using descriptive statistics. The result showed that 128,726.28 hectares of gully rehabilitation had been carried out, 4,436,096.3033 hectares of cultivated fields have received SWC measures, and SWC measures were done on 817,104.7 hectares of communal land. Despite these commendable initiatives, it was found that 46% of the community-mobilized SWC structures built on cultivated land have been partially or entirely removed, additionally, 66% of the constructed SWC structures lack support by biological measures. Furthermore, the survey revealed that 20% of the respondents’ land holdings were affected by gullies, and a 43% decrease trend in efforts to combat gully erosion since 2011. This study demonstrates the significance of implementing SWC measures for the sustainability of the watershed. It also underscores the vital role of regular maintenance in enhancing the effectiveness of the structures, along with the imperative need to reinforce the SWC structures using biological measures. Moreover, the research stresses the importance of rehabilitating communal lands through enclosure and improving cropland soil fertility by applying organic compost.

Soil erosion is the most serious problem that affects economic development, food security, and ecosystem services, which is the main concern in Ethiopia. This study focused on quantifying soil erosion rate and severity mapping of the Megech watershed for effective planning and decision-making processes to implement protection measures. The RUSLE model integrated with ArcGIS software was used to accomplish the objectives. The six RUSLE model parameters: erosivity, erodibility, slope length and steepness, cover management, and erosion control practices were used as input parameters to compute the average annual soil loss and identify erosion hotspots in the watershed. The RUSLE estimated a total soil loss of 1,399,210 t yr−1 from the watershed with a mean annual soil loss of 32.84 t ha−1yr−1. The soil erosion rate varied from 0.08 to greater than 500 t ha−1yr−1. A severity map with seven severity classes was created for 27 sub-watersheds: low (below 10), moderate (10–20), high (20–30), very high (30–35), severe (35–40), very severe (40–45) and extremely severe (above 45) in which the values are in ton ha−1yr−1. The area coverage was 6.5%, 11.1%, 8.7%, 22%, 30.9%, 13.4%, and 7.4% for low, moderate, high, very high, severe, very severe, and extremely severe erosion classes, respectively. About 82% of the watershed was found in more than the high-risk category which reflects the need for immediate land management action. This paper could be important for decision-makers to prioritize critical erosion hotspots for comprehensive and sustainable management of the watershed.

Crop modeling is a powerful tool for estimating yield and water use efficiency, and it plays an important role in determining water management strategies. Under the condition of scarce water supply and drought, deficit irrigation can lead to greater economic gains by maximizing yield per unit of water. Studies have shown that deficit irrigation significantly increased yield, crop evapotranspiration, and water use efficiency as compared to full irrigation requirement. However, this approach requires precise knowledge of crop response to water as drought tolerance varies considerably by growth stage, species and cultivars. This study was conducted in Lasta district, for two successive years to evaluate the effects of water shortage on potato production and water use efficiency, as well as to test the AquaCrop model for potato-producing areas. The irrigation water levels for potatoes were 100%, 75%, and 50% of crop evapotranspiration (ETc). Six treatments were arranged using a randomized complete block design. Climate, soil, and crop data were calibrated using observed weather parameters, and measured crop parameters conducted in the 2018/19 growing season. The model was validated using the observed data conducted in the 2019/20 growing season. The calibration of the model revealed a good fit for canopy cover (CC) with a coefficient of determination ( R 2 ) = .98, Root mean square error (RMSE) = 9.6%, Nash-Sutcliffe efficiency ( E ) = 0.92, index of agreement ( d ) = 0.98, and coefficient of residual moss (CRM) = −0.07, and good prediction for biomass ( R 2 = .98, RMSE = 1.8 t ha −1 , E = 0.96, d = 0.99, CRM = −0.13). Similarly, the validation result showed good fit for CC by 100% water application at development and mid growth season and a 75% water applied at the other stages ( R 2 = .98, RMSE = 9.4%, E = 0.94, d = 0.98, CRM = −0.12). The AquaCrop model is simple to use, requires fewer input data, and has a high level of simulation precision, making it a useful tool for forecasting crop yield under deficit irrigation and water management to increase agricultural water efficiency in data-scarce areas.

Abstract Background Assessment of suitable lands for irrigation is indispensable to plan and implement different programs in a cost-effective approach for sustainable land use planning and efficient utilization of the land. Hence selecting proper land use based on land suitability evaluation will enhance the productivity per unit area and ensures the sustainable use of land resources. Therefore, the research was designed to evaluate the suitability of the soil properties of Zamra irrigation scheme for irrigation purposes. Method For this study about 195.16 ha of land were evaluated for irrigation suitablity. Four soil profile pits were opened in the representative site of the scheme based on slope, texture, soil color and soil depth. Soil samples were collected from the soil mapping units for analysis of texture, electrical conductivity, and calcium carbonate content, whereas slope, drainage and soil depth were directly measured at the field. The evaluation was carried out using a parametric evaluation method. Results The results of the study revealed that four types of soils were identified namely, Rehodic Nitisol(eutric), Haplic Regosol (eutric) Eutric Regosol, Leptic Regosol (eutric, loamic), and Vertic Cambisol (Hypereutric). The soil texture consists of sandy loam and sandy clay loam at the surface and subsurface soil and the soil depth of study area varied from shallow to very deep. The soil of the scheme was free from salinity and the status of calcium carbonate was at a low level. The slope of the study area was ranged from flat (0–3%) to slopping (8–15%). Generally, 80.64 ha (41.32%) of the scheme was moderately suitable whereas 71.68 ha (36.73%) of the land was marginally suitable for irrigation. Due to major limiting factors of soil depth and slope about 42.84 ha of the land (21.95%) were not currently suitable for irrigation. Conclusion In the study area, the major limitations were slope and soil depth. Therefore, to increase production and productivity of the scheme, land improvement operations are suggested.

Abstract Obesity significantly impairs breathing during exercise. The aim was to determine, in male obese adolescents (OB), the effects of acute respiratory muscle unloading, obtained by switching the inspired gas from ambient air (AIR) to a normoxic helium + oxygen gas mixture (HeO2) (AIR → HeO2) during moderate [below gas exchange threshold (GET)] and heavy [above GET] constant work rate cycling. Ten OB [age 16.0 ± 2.0 years (mean ± SD); body mass index (BMI) 38.9 ± 6.1 kg/m2] and ten normal-weight age-matched controls (CTRL) inspired AIR for the entire exercise task, or underwent AIR → HeO2 when they were approaching volitional exhaustion. In OB time to exhaustion (TTE) significantly increased in AIR → HeO2 vs. AIR during moderate [1524 ± 480 s vs. 1308 ± 408 (P = 0.024)] and during heavy [570 ± 306 s vs. 408 ± 150 (P = 0.0154)] exercise. During moderate exercise all CTRL completed the 40-min task. During heavy exercise no significant differences were observed in CTRL for TTE (582 ± 348 s [AIR → HeO2] vs. 588 ± 252 [AIR]). In OB, but not in CTRL, acute unloading of respiratory muscles increased TTE during both moderate- and heavy-exercise. In OB, but not in CTRL, respiratory factors limit exercise tolerance during both moderate and heavy exercise.

The Ethiopian highlands are affected by soil erosion resulting in the deterioration of soil properties. To reverse this, different soil and water conservation (SWC) measures were spatially practiced; however, the effect of SWC and slope gradient on soil properties is not well studied in the area. Hence, this study was conducted to evaluate the effects of SWC and slope gradient on selected soil physicochemical properties in Dawnt watershed, northwestern Ethiopia. The treatments were a combination of four different SWC measures on three slope gradients replicated at three sites. Disturbed and undisturbed soil samples were collected from 0–20 cm soil depth, and physicochemical properties were determined following standard laboratory procedures. The laboratory results depict that sand, bulk density, moisture, particle density, porosity, pH, organic carbon (OC), cation exchange capacity (CEC), total nitrogen, and available phosphorus were significantly (P

Abstract A subgrid‐scale eddy parameterization is developed, which makes use of an explicit eddy kinetic energy budget and can be applied at both “non‐eddying” and “eddy‐permitting” resolutions. The subgrid‐scale eddies exchange energy with the resolved flow in both directions via a parameterization of baroclinic instability (based on the established formulation of Gent and McWilliams) and biharmonic and negative Laplacian viscosity terms. This formulation represents the turbulent cascades of energy and enstrophy consistent with our current understanding of the turbulent eddy energy cycle. At the same time, the approach is simple and general enough to be readily implemented in ocean climate models, without adding significant computational cost. The closure has been implemented in the Modular Ocean Model Version 6 and tested in the “Neverworld” configuration, which employs an idealized analytically defined topography designed as a testbed for mesoscale eddy parameterizations. The parameterization performs well over a range of resolutions, seamlessly connecting non‐eddying and eddy‐resolving regimes.

Understanding soil types of a given area is an important prerequisite to design optimum management strategies such as irrigation water management. The study was thus conducted on characterization and classification of Zamra irrigation scheme in Abergelle district of Amhara Region, which has an area of 196.16 ha. For this study, 53 auger observations, four profile pits, extensive visual observations, reconnaissance survey, and descriptions of soil profiles and laboratory analysis were used to study the morphological and physicochemical properties of the soils of the scheme. Twelve disturbed and undisturbed soil samples were collected from all profiles of each genetic horizon for laboratory analysis. The soils of the study area were identified based on Food and Agricultural Organization of the United Nations/World Reference Base for Soil Resources (FAO/WRB) 2015. The results revealed that the textural classes of all profiles of the study site ranged from sandy clay loam to sandy loam. The chemical properties of the soil in terms of total nitrogen, organic matter, and available phosphorus were in the very low and low categories as per the criteria developed by Tekalign and Olsen, respectively, whereas exchangeable bases (Ca, Mg, K, and Na), cation exchange capacity, and extractable micronutrients (Fe, Mn, Zn, and Cu) were medium to high. Based on morphological, physical, and chemical analyses, the soils were classified as Leptic Regosols (Eutric, Loamic; 21.99% of the area), Vertic Cambisols (Hypereutric; 17.87%), Haplic Regosols (Eutric; 36.69%), and Rhodic Nitisols (Eutric; 23.44%). Therefore, management techniques that enhance soil fertility (including crop rotations, manuring, fallow periods, proper management of crop residues, and leguminous cover crops) and water-saving technologies suitable to the terrain of the area are the best options to enhance land productivity in the area.

Soil erosion is one of the major environmental threats in the northwestern Amhara Region of Ethiopia. The objective of this study is to assess the spatial heterogeneity of soil erosion risk within the Gumara-Maksegnit watershed (57.3 km2) using the Coordination of Information on the Environment (CORINE) soil erosion assessment method to determine the most endangered areas. The model is simple and robust and consists of six steps overlaying combinations of soil texture, depth, stoniness, climatic and land-use/land-cover information with GIS support. The CORINE model was used to produce potential and actual soil erosion maps. The potential soil erosion map consists of the erosion risk of the land without considering current vegetation, but can be expanded to consider current land cover. The potential soil erosion risk map showed that a small part of the watershed (6.63 %) had low risk, 17.92 % had moderate risk and a large part of the study area (75.45 %) had high potential erosion risk. Meanwhile, the actual soil erosion risk map showed that a small part of the watershed (11.92 %) had low risk, 20.85 % of the area had moderate risk, and a large part of the study area (67.23 %) had high actual soil erosion risk. Low soil erosion risk areas were located in the southern part of the watershed, high erosion risk areas were found in the northern, northwestern and eastern part of the watershed, while moderately risky areas were randomly distributed throughout the watershed. Overall, the CORINE model can play a role in soil and water conservation by identifying highly endangered areas.

The study was conducted in Gumara-Maksegnit watershed to evaluate the impacts of 5-years old stone bunds on soil pH, Organic matter (OM), available phosphorous (Av. p), cation exchange capacity (CEC), available potassium (K+), soil moisture content (SMC), and crop yield. The experiment has two treatments, three bund positions, and three intra-bund positions with three replications. The experiment has two data sets: (i) 27 data points for treated farmland (three consecutive bunds*three intra-bund positions*three replications) arranged in split-plot design as a main and sub-plots, (ii) a pair of 9 data points of treated and untreated farmland for a paired mean comparison. The result showed that pH was significantly different between the main plots where the highest value (7.07) observed at the lower bund due to sediment accumulation with soluble bases. Meanwhile, OM, Av. p, and SMC were significantly different between sub-plots where the highest mean values observed in the deposition zone. On the other hand, soil properties such as OM, CEC, and SMC were significantly higher in conserved farmland as compared to non-conserved farmland. The grain yield of sorghum (Sorghum bicolor L.) and chickpea (Cicer arietinum) was significantly different between conserved and non-conserved farmlands. The yield advantages due to stone bund intervention were 8.46% and 28.51% for sorghum (Sorghum bicolor L.) and chickpea (Cicer arietinum), respectively. Therefore, proper implementations of stone bunds in the study area have a pronounced positive impact and should be practiced and applied in adjacent watersheds and similar agro-ecologies.

Recent research findings imply that the slope aspect has a great impact on soil genesis and soil microclimate. The microclimate has a significant effect on the soil geobiochemical processes taking place in the soil. However, the slope aspect impact on soil properties has not been yet studied well in Ethiopia, particularly in the northern highlands. This research was initiated to link selected soil physicochemical properties with slope aspects under different land use practices. The research was conducted in Gumara-Maksegnit watershed located at the upper Lake Tana basin, Ethiopia. Four slope aspects, eastward (Ew), northward (Nw), southward (Sw), and westward (Ww), and three land use types at each slope aspect, cropland (Cl), forest land (Fl), and grazing land (Gl), were considered. In total, 36 undisturbed soil samples for bulk density and 36 disturbed soil samples for selected soil properties were collected. Soil particle size (texture), bulk density, electrical conductivity (EC), soil pH, available phosphorus (av. P), available potassium (av. K), total nitrogen (TN), and soil organic carbon (SOC) were analyzed. The resulting analyses showed no significant variation (p Gl > Cl for SOC and TN. A strong positive correlation was observed between SOC and TN (R2 = 0.997) and av. K and av. P (R2 = 0.58) at p

Soil erosion in the northwestern Amhara region, Ethiopia has been a subject of anxiety, resulting in a major environmental threat to the sustainability and productive capacity of agricultural areas. This study tried to estimate soil erodibility factor (K-factor) using Universal Soil Loss Equation (USLE) nomograph, and evaluate the spatial distribution of the predicted K-factor in a mountainous agricultural watershed. To investigate the K-factor, the 54 km2 study watershed was divided into a 500 m by 500 m square grid and approximately at the center of each grid, topsoil samples (roughly 10 to 20 cm depth) were collected over 234 locations. Sand, silt, clay and organic matter (OM) percentage were analyzed, while soil permeability and structure class codes were obtained using the United States Department of Agriculture (USDA) document. The resulting coefficient of variation (CV) of the estimated K-factor was 0.31, suggesting a moderate variability. Meanwhile, the value of nugget to sill ratio of K-factor was 0.32, which categorized as moderate spatial autocorrelation. Prediction accuracy and model fitting effect of the Gaussian semivariogram approach was best, suggesting that the Gaussian ordinary Kriging model was more appropriate for predicting K-factor. The resulting value of the mean error (ME) was 0 and the mean squared deviation ratio (MSDR) was nearly 1, which indicates the Gaussian model was unbiased and reproduced the experimental variance sufficiently. The values of K-factor were smaller (0.0217 to 0.0188) in the northern part and gradually increased (0.0273 to 0.033 Mg h MJ−1 mm−1) towards the central and south of the study watershed.

Food safety is an important public health issue in the U.S. Eating at restaurants and other food service facilities increasingly has been associated with food borne disease outbreaks. Food safety training and certification of food mangers has been used as a method for reducing food safety violations at food service facilities. However, the literature is inconclusive about the effectiveness of such training programs for improving food safety and protecting consumer health. The purpose of this study was to examine the effect of food manger training on reducing food safety violations. We examined food inspection reports from the Toledo/Lucas County Health Department (Ohio) from March 2005 through February 2006 and compared food hygiene violations between food service facilities with certified and without certified food managers. We also examined the impact on food safety of a food service facility being part of a larger group of facilities. Restaurants with trained and certified food managers had significantly fewer critical food safety violations but more non-critical violations than restaurants without certified personnel. Institutional food service facilities had significantly fewer violations than restaurants, and the number of violations did not differ as a function of certification. Similarly, restaurants with many outlets had significantly fewer violations than restaurants with fewer outlets, and training was not associated with lower numbers of violations from restaurants with many outlets. The value of having certified personnel was only observed in independent restaurants and those with few branches. This information may be useful in indicating where food safety problems are most likely to occur. Furthermore, we recommend that those characteristics of institutional and chain restaurants that result in fewer violations should be identified in future research, and efforts made to apply this knowledge at the level of individual restaurants.

Gully erosion is a serious threat to the society and environment of the study, primarily caused by surface runoff and dramatically accelerated due to rugged topography and human induced factors. Intensive measurements of gully characteristics were undertaken to investigate the morphologies of gully, while aiming for sustainable gully rehabilitation; therefore, a total of 63 gully samples from three different agroecologies were randomly observed. The morphological variability of measured gullies was evaluated and the resulting CVs had been between 0.27 and 0.39 except for gully length, which had highest variability (CV = 1.10). The highest gully length (2,400 m) and highest lower width (6 m) were observed on Dembia district, which might be due to the loose and pulverized condition of the soil. The correlation matrices for many parameters of gully morphology in different districts of Semien Gondar showed several sets of significant relationships. Some of the assessed gullies showed that appropriate physical gully control structures integrated with vegetative measures have resulted in a significant reduction of soil loss and stabilized the gully from further enlargement. There could be various justifications for the success of these structures; however, the most important measures were vegetative management and exclusion of cattle.

A yearling quarter horse, which was raised in southern California, received routine vaccinations for prevention of infection by Eastern equine encephalomyelitis virus (EEEV). One week later, severe neurologic signs developed, and the horse was humanely destroyed because vaccine-related encephalomyelitis was suspected. A final diagnosis of EEEV infection was established on the basis of acute onset of the neurologic signs, histopathologic and serologic testing, and isolation and molecular characterization of EEEV from brain tissue. The vaccine was extensively tested for viral inactivation. Nucleotide sequences from the vaccine and the virus isolated in the affected horse were also compared. In California, arboviral encephalomyelitides are rarely reported, and EEEV infection has not previously been documented. This report describes the occurrence of EEEV infection in the horse and the investigation to determine the source of infection, which was not definitively identified.

Geostrophic turbulent eddies play a crucial role in the oceans, mixing properties such as heat, salt, and geochemical tracers. A useful reduced model for geostrophic turbulence is barotropic (2D) turbulence. The focus of this study is on 2D β -plane turbulence with quadratic drag, which, although arguably the most realistic barotropic model of ocean turbulence, has remained unexplored thus far. We first review and test classical scaling arguments for the eddy diffusivity in three regimes: the strong friction limit, the weak friction/strong β limit, and a transition regime. We then develop a generalized theory by parameterizing the nonlinear eddy–eddy interactions as a stochastic process, which leads to an analytical solution for the eddy diffusivity spectrum, whose integral yields a “bulk” diffusivity. The theory successfully predicts the smooth transition of diffusivity across the three regimes, and echoes with the recent argument that eddy phase propagation relative to the mean flow suppresses the eddy diffusivity. Moreover, the generalized theory reduces to the classical scaling arguments in both the strong friction and strong β limits, which has not been clear from the previous work on diffusivity suppression by flow-relative phase propagation.

BACKGROUND: Cryptosporidiosis is an important cause for chronic diarrhea and death in HIV/AIDS patients. Among common Cryptosporidium species in humans, C. parvum is responsible for most zoonotic infections in industrialized nations. Nevertheless, the clinical significance of C. parvum and role of zoonotic transmission in cryptosporidiosis epidemiology in developing countries remain unclear. METHODOLOGY/PRINCIPAL FINDINGS: In this cross-sectional study, 520 HIV/AIDS patients were examined for Cryptosporidium presence in stool samples using genotyping and subtyping techniques. Altogether, 140 (26.9%) patients were positive for Cryptosporidium spp. by PCR-RFLP analysis of the small subunit rRNA gene, belonging to C. parvum (92 patients), C. hominis (25 patients), C. viatorum (10 patients), C. felis (5 patients), C. meleagridis (3 patients), C. canis (2 patients), C. xiaoi (2 patients), and mixture of C. parvum and C. hominis (1 patient). Sequence analyses of the 60 kDa glycoprotein gene revealed a high genetic diversity within the 82 C. parvum and 19 C. hominis specimens subtyped, including C. parvum zoonotic subtype families IIa (71) and IId (5) and anthroponotic subtype families IIc (2), IIb (1), IIe (1) and If-like (2), and C. hominis subtype families Id (13), Ie (5), and Ib (1). Overall, Cryptosporidium infection was associated with the occurrence of diarrhea and vomiting. Diarrhea was attributable mostly to C. parvum subtype family IIa and C. hominis, whereas vomiting was largely attributable to C. hominis and rare Cryptosporidium species. Calf contact was identified as a significant risk factor for infection with Cryptosporidium spp., especially C. parvum subtype family IIa. CONCLUSIONS/SIGNIFICANCE: Results of the study indicate that C. parvum is a major cause of cryptosporidiosis in HIV-positive patients and zoonotic transmission is important in cryptosporidiosis epidemiology in Ethiopia. In addition, they confirm that different Cryptosporidium species and subtypes are linked to different clinical manifestations.

Salmonella bacteria continue to be an important public-health problem and have a serious economic impact on the U.S. poultry industry. Although the majority of human infections traceable to Salmonella enteritidis are related to egg consumption, this serotype has also been isolated from a variety of nonegg food items such as meat, vegetables and fish. In Southern California, S. enteritidis phage type 4 infection is the predominant serotype found in human patients. However, the organism has also been found in municipal sewage effluent and in rodent and poultry environments. S. enteritidis phage type 4 was first detected in human patients in Southern California in 1990, but wasn't isolated from food-producing animals until its occurrence at a Southern California egg-layer ranch in 1994. An epidemiological study revealed that the layer flock was infected via effluent originating from a nearby municipal sewage-treatment plant. Human sewage effluent was the primary environmental source, combined with wildlife that further amplified and disseminated the bacteria. This discovery has important implications for understanding the ecology of S. enteritidis infection in poultry and humans and developing appropriate methods to prevent its further spread.