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Irrigation water contaminated with industrial waste could pollute the soil and vegetables with heavy metals. The objective of this study was to analyze the concentration of heavy metals in soil and vegetables after irrigation practices with wastewater emanating from industrial parks. 24 samples were collected from 8 sampling stations for vegetable, soil and water samples separately, following APHA procedures. Samples were collected using a composite sampling method in May and June 2021. Water samples were collected using clean polyethylene plastic bottles while soil and vegetables were sampled using clean plastic bags. Analysis was done for heavy metal concentrations such as Pb, Cr, Cd, and Zn for each sample using descriptive statistics of changes in concentrations, one-way analysis of variance (ANOVA), Principal Component Analysis and Pearson Correlation Coefficient. The mean concentration of heavy metals in soil, vegetables, and water samples was analyzed. Unlike the rest of the heavy metal concentrations, the result showed the highest levels for Zn, i.e., 7.82 mg/kg and 5.12 mg/kg for vegetables and soil samples, respectively. The maximum value of the bioconcentration factor (BCF), the highest value of Estimated Daily Intake (EDI), and the maximum Target Cancer Risk (TCR) value recorded were 19.39, 0.001, and 8.09 × 10−5 for Cd, Zn, and Cr, respectively. But, Hazard Index (HI) indicated no potential health effects. On the other hand, the concentration of heavy metals in the soil sample showed that Cr and Cd were strongly positively correlated with the concentration of Pb in vegetables during May. Cd concentration in the water sample was also strongly positively correlated with the concentration of Pb during May. The application of proper management for the reduction of contaminants, and suitable irrigation methods with treated wastewater is essential. The study can provide a basis for the City Administration of Addis Ababa to properly protect the water quality of rivers and provide a reference for river management around the industry parks across the country.

Understanding the variability of soil quality indicators across topographic positions and agroecosystems (AES) is critical for improving soil fertility, productivity, and environmental sustainability. This study evaluates the variability of soil quality indicators along with the different landscape positions (upper, middle, and lower slopes) among the five AES of the Choke Mountain watershed in the upper Blue Nile Basin. A total of forty soil samples were gathered from Choke Mountain's five AES, upper, middle, and lower landscape positions. Principal component analysis (PCA) was used to determine the minimum datasets (MDS) from fourteen soil quality indicators. Using multivariate analysis of variance (MANOVA), the variability of soil quality indices among AES of the Choke, as well as variation with landscape positions, was investigated. The interaction effect of AES and topo-sequence (AES∗topo-sequence) has a substantial effect on three soil quality indicators, including soil silt content, soil pH, and available phosphorus. The highest mean value of silt content was found in the upper position of the hilly and mountainous highlands (AES 5), while the lowest was found in the lower part of the midland plain with black soil (AES 2). The highest mean pH of the soil was found in the lower part of the lowland and valley fragments (AES 1), and the lowest was in the lower position of the midland plain with brown soil (AES 3). The highest record of available P was found in AES 1's middle position and the lowest in AES 3's upper positions. AES had a significant impact on cation exchange capacity (CEC), and both AES and topography had a significant and distinct impact on organic matter (OM). Thus, the study suggests site-specific solutions to improve agricultural productivity and ease the constraints associated with each soil in each topo-sequence and AES.

Background: Due to its climate-sensitive agricultural system and low adaptive capacity of the subsistence farmers, Ethiopia is cited among the countries experiencing frequent drought and highly vulnerable to climate change associated impacts. Micro level vulnerability assessment, in the context of a changing climate, has a paramount significance in designing policies addressing climate change induced effects. Assessing vulnerability to climate change is important for defining the risks posed by the change and it provides a starting point for the determination of effective means of promoting remedial actions to minimize impacts by supporting coping strategies and facilitating adaptation options targeted at specific context. Methods: We employed cross-sectional survey research design has to examine the extent of livelihood vulnerability of 384 randomly selected smallholder farmers from three agroecologies which was supplemented by interviews. Livelihood vulnerability index, using integrated indicator approaches and principal component analysis, has been used. Chi-square test, F-test and t-test were used to examine association and mean differences among three agroecologies and between cropping types in terms of different attributes. Findings: Overall, smallholder farmers living in kolla agroecology were found to be the most vulnerable to climate change induced hazards followed by dega. In terms of type of cropping season, belg dominated areas were relatively more vulnerable than those residing in meher dominated areas. Different biophysical and socio-economic attributes contributed their own role both for exposure, sensitivity and adaptive capacity differences among smallholder farmers farming in different agroecologies and different types of cropping seasons. Conclusion: We recommend that interventions undertaken to lessen the impact of climate change should be targeted to the factors which contribute to high extent of sensitivity and for those which could enhance the adaptive capacity of smallholder farmers. Specifically, we suggest that resilience-building adaptation interventions like expansion of small-scale irrigation, accessing of microfinance service, early warning and timely information, extension support, non-farm sources of income, training and skill development, expansion of infrastructure have to be promoted thereby increase the adaptive capacity of subsistence rainfed-dependent farmers to withstand the vagaries of the climate variability risk. Moreover, disparities in the same agroecology have to be addressed properly in livelihood vulnerability discourse.