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A study was conducted to determine the effect of different land use systems on soil physical and chemical properties in Sodo Zuria Woreda of Wolaita zone Southern Ethiopia. Differences in soil properties in different land use types at two depths (0-15 and 15-30 cm) were observed on many soil properties important to crop growth. Enset (Ensete Ventricosum) fields had higher pH, electrical conductivity (EC), available P and Zn, exchangeable Ca and K which is attributed due to the addition of manure, whereas maize fields had lowest average K and Mg, cation exchange capacity (CEC), percentage of base saturation (PBS), total N and OC. These results suggest that land use has persistent, multi-decadal effects on the spatial heterogeneity of soil resources and also the need of land use and landscape research to determine ecologically sound and sustainable land use and management strategies.

Increasing areas of agricultural land in high rainfall areas of Sub-Saharan Africa (SSA), where crop production used to be reliable, are affected by soil acidity. This review focuses on the extent, causes and effect of soil acidity on soil properties and crop yield and its management from the context of SSA. Studies showed that the detrimental effects of soil acidity can be mitigated through liming, integrated acid soil management and the use of acid-tolerant germplasms. Application of lime resulted in yield increments of 34-252% in wheat, barley and tef, 29-53% in faba bean and soybean, and 42-332% in potato in Ethiopia, 111-182% in maize in Kenya, and 45-103% in Mucuna in Nigeria under moderate to severe acid soil conditions. This was accompanied by a corresponding increase in soil pH up to 1.9 units and a decrease in exchangeable acidity and aluminum up to 2.1 cmol kg −1 . Use of acid-tolerant crop varieties such as maize expressing superior tolerance to Al toxicity resulted in a yield increase of 51% under low soil pH in Cameroon and Kenya. Overall, soil acidity covering ∼35% of SSA should be reclaimed with lime and integrated acid soil management interventions, which could significantly increase crop yield and enhance the resilience of the tropical agroecosystems. .

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Rainfall is the most important source of water for crop production in Ethiopia. However, its temporal and spatial variability is leading to serious food shortages and insecurity in the country. This study was aimed at investigating the characteristics of selected agroclimatic variables over the great Rift Valley regions of Ethiopia. Long term (1981–2010) climate data were analyzed for 17 stations selected based on agroecology representation. Selected descriptors for climate variability and the Mann–Kendall trend test were employed. Onset, cessation, length of growing period (LGP), water requirement satisfaction index and dry spell occurrence during the growing period were determined. The results showed low to very high rainfall variability (14–35%), LGP (20–256 days) and dry spell probability (50–100%) during the main season. Significant (P ≤ 0.05) annual and seasonal rainfall trends were observed in some stations. The probability of occurrence of a dry spell during the seasons was found to be a challenge for most of the stations in the mid and low altitude areas of the basins. Consequently, seasonal water deficit was observed in these areas which hampered crop production. Area specific recommendations are thus required based on specific challenges in the study region.