Abstract The aim of this study was to understand the association of crop production with climate variability in the central highlands of Ethiopia. We used monthly rainfall and temperature data from 132 points each representing a pixel of 10×10 km, which are reconstructions based on station records and meteorological satellite observations. Production data of five major crops for the main cropping season, locally known as Meher, were collected for the period 2004–2013 for three districts (Baso Werana, Efratana Gidim and Menz Gera Meder) from the Central Statistical Agency (CSA). The production data are at the Enumeration Area (EA 1 1 Enumeration Areas (EAs) are small spatial units from which crop production data are collected by the Central Statistical Agency of Ethiopia as a basis to estimate national level production. The data are therefore the best available on crop production. On average an EA consists of 150–200 households. ) level and hence the best available dataset on crop production. Therefore, there is no published local scale study, as is attempted here, on local scale climate variability and crop production in the country insofar as it is known to the authors. Correlation analysis shows that crop production and cultivated area are positively correlated with rainfall, but negatively associated with maximum and minimum temperatures except for one of the districts, Basona Werana, where production of all crops are positively associated with the minimum temperature. Production of four out of five crops in Basona Werana and three out of five crops in both Efratana Gidim and Menz Gera Meder, showed declines over the period of study; regression results indicating rainfall to be the most important determinant of production levels. It is concluded that current climate variability has a significant influence on crop production in the area and any unfavorable change in the local climate in the future will have serious implications for household level food security. Efforts to adapt to the ongoing climate change should begin from tackling the current climate variability and take a climate risk management approach for adapting to the ongoing climate change.

The aim of this study is to characterise rainfall variability and trend in the drought-prone Amhara Regional State of Ethiopia using standard rainfall statistical descriptors. A review of previous studies of Ethiopian rainfall shows different conclusions between studies about the existence of trends primarily due to their use of different periods of analysis. Various rainfall indicator series are presented and analysed for trend on annual, seasonal and daily time steps (including wet-day amounts and probabilities, percentiles and dry spell lengths). Two periods are used for analysis: 1975-2003 (12 stations) to optimise station density and 1961-2003 (five stations) to optimise record length in this relatively poorly monitored region. A complex picture of rainfall variability emerges from the analysis, both in terms of spatial variability and temporal variability, from decadal to daily timescales. The results generally support those of the previous studies in Ethiopia with the additional findings that: (1) High levels of spatial variability exist at subregional scales in Ethiopia that are unlikely to be fully explained by large-scale climate influences; (2) Choice of study period strongly influences the results of trend analysis in this region due to the effects of decadal variability (particularly because the 1980s was the driest decade and the 1990s the wettest decade on record); (3) Annual rainfall in the region recovered during the 1990s, although 2001 -2003 were average or slightly lower; and (4) There are no consistent emergent patterns or trends in daily rainfall characteristics in this part of Ethiopia.

Abstract The objective of this study was to analyse changes in stream flow patterns with reference to dynamics in land cover/use in a typical watershed, the Chemoga, in northwestern highland Ethiopia. The results show that, between 1960 and 1999, total annual stream flow decreased at a rate of 1 · 7 mm year−1, whereas the annual rainfall decreased only at a rate of 0 · 29 mm year−1. The decrease in the stream flow was more pronounced during the dry season (October to May), for which a statistically significant decline (0 · 6 mm year−1) was observed while the corresponding rainfall showed no discernible trend. The wet season (June to September) rainfall and stream flow did not show any trends. Extreme low flows analysed at monthly and daily time steps reconfirmed that low flows declined with time, the changes being highly significant statistically. Between 1960 and 1999, the monthly rainfall and stream flow amounts of February (month of lowest long-term mean flow) declined by 55% and 94% respectively. Similarly, minimum daily flows recorded during the three driest months (December to February) showed statistically highly significant declines over the same period. It declined from 0 · 6 m3 s−1 to 0 · 2 m3 s−1 in December, from 0 · 4 m3 s−1 to 0 · 1 m3 s−1 in January and from 0 · 4 m3 s−1 to 0 · 02 m3 s−1 in February (1 · 0 m3 s−1 = 0 · 24 mm day−1 in the Chemoga watershed). In contrast, extreme high flows analysed at monthly (for August) and daily (July to September) time steps did not reveal discernible trends. The observed adverse changes in the stream flow have partly resulted from changes in land cover/use and/or degradation of the watershed that involved destruction of natural vegetative covers, expansion of croplands, overgrazing and increased area under eucalypt plantations. The other contributory factor has been the increased dry-season water abstraction to be expected from the increased human and livestock populations in the area. Given the significance of the stream flow as the only source of water to the local people, a set of measures aimed at reducing magnitudes of surface runoff generation and increasing groundwater recharge are required to sustain the water resource and maintain a balanced dry-season flow in the watershed. Generally, an integrated watershed management approach, whereby the whole of the watershed can be holistically viewed and managed, would be desirable. Copyright © 2004 John Wiley & Sons, Ltd.

This study appraises the effects of land use on soil properties in a typical watershed in the northwestern highland of Ethiopia. Soil samples were collected from major land use types in the watershed: natural forests, cultivated lands, grazing lands and Eucalyptus plantations. The natural forests served as a control against which to assess changes in soil properties resulting from the establishment of the other land use types. Samples were taken at two depths (0-15 and 15-30 cm) in the upstream and downstream areas of the watershed and analyzed for a range of soil properties. The soils in the cultivated fields, grazing lands and Eucalyptus plantations showed significantly higher sand content, but lower Ca2+ and Mg2+ contents and cation exchange capacity (CEC) compared to soils under natural forests. Eucalyptus soils had a statistically significant higher bulk density (BD) than soils under the other three land use types. The forest and Eucalyptus soils also differed significantly from each other in their soil organic matter (SOM) and total N contents. A significant difference in available P among soils of the four land use types was caused by the difference between cultivated and Eucalyptus soils. In contrast, the distribution of soil silt fraction Na+, K+ and pH values did not differ among the four land use types. Significant differences in many of the soil properties were also observed between soils in the two sampled villages. The study underscores the need for policies and strategies for sustainable land use that will attune objectives of economic development to environmental management at the regional and local levels.

Soil erosion by water is recognized to be a critical economic problem in highland Ethiopia. However, nearly all the available information about its severity and economic costs are extrapolated from plot and micro-watershed level studies which are too few in number to represent the diverse environments of the country. Moreover, plot and watershed level studies do not show actual soil losses from cultivated fields, while understanding the magnitude of soil loss at the field scale is important for practical conservation planning. This paper reports results of field-scale soil erosion assessment that employed a survey methodology for rills and was conducted over two wet seasons (the years 2000 and 2001) at two sites, Kechemo and Erene, located in the upstream and downstream reaches of the Chemoga watershed, northwestern highland Ethiopia. The two wet seasons average rill erosion magnitudes were 13.5 Mg ha-1 in the Kechemo and 61 Mg ha-1 in the Erene. Assuming that interrill erosion contributes 30%, actual soil losses were around 18 Mg ha-1 in the Kechemo and 79 Mg ha-1 in the Erene. These estimates, which are well in agreement with results obtained by measurements in a nearby experimental micro-watershed, reveal that soil erosion is a threat to agricultural production in the study area and conservation measures are needed. Soil erosion showed significant spatial (between and within the two sites) and temporal variations. Hence, soil and water conservation (SWC) measures that fit well into local-scale circumstances will be realistic and acceptable to the farmers. Additionally, the problem of soil erosion should be tackled in the watershed context, because there is a strong physical interdependence between upstream and downstream areas. Finally, the study confirms that the rill survey approach gives good semi-quantitative information on soil erosion in real life situations of diverse farming and land use practices in a fast and inexpensive way; and it is commendable for practical conservation-oriented soil erosion assessment purposes.

This study examines farmers’ acceptance and adoption of soil and water conservation (SWC) technologies that were claimed by the implementing agency to have been executed in a farmer-participatory approach in a representative micro-watershed (the Digil watershed) in the north-western highlands of Ethiopia. Multiple methods of social research were employed to generate the data. The results reveal that involvement of the farmers was essentially limited to ‘participation by consultation’ and the farmers were rather persuaded to implement the conservation measures. A large majority of the farmers, however, acknowledged that the introduced conservation technologies were effective measures against soil erosion and for improving land productivity. Notwithstanding, the sustainable adoption and widespread replication of the technologies seemed unlikely. The major factors that were discouraging the farmers from adopting the technologies on their farms were found to be labour shortage, problem of fitness of the technologies to the farmers’ requirements and farming system circumstances, and land tenure insecurity. The study underscores that many of these problems were also basically related to lack of a genuine involvement of the farmers in the conservation effort and concludes by suggesting that future SWC interventions should carefully pursue a farmer-participatory approach.

This study examines farmers’ acceptance and adoption of soil and water conservation (SWC) technologies that were claimed by the implementing agency to have been executed in a farmer-participatory approach in a representative micro-watershed (the Digil watershed) in the north-western highlands of Ethiopia. Multiple methods of social research were employed to generate the data. The results reveal that involvement of the farmers was essentially limited to ‘participation by consultation’ and the farmers were rather persuaded to implement the conservation measures. A large majority of the farmers, however, acknowledged that the introduced conservation technologies were effective measures against soil erosion and for improving land productivity. Notwithstanding, the sustainable adoption and widespread replication of the technologies seemed unlikely. The major factors that were discouraging the farmers from adopting the technologies on their farms were found to be labour shortage, problem of fitness of the technologies to the farmers’ requirements and farming system circumstances, and land tenure insecurity. The study underscores that many of these problems were also basically related to lack of a genuine involvement of the farmers in the conservation effort and concludes by suggesting that future SWC interventions should carefully pursue a farmer-participatory approach.

During the last 100 years the Ethiopian upper Blue Nile Basin (BNB) has undergone major changes in land use, and is now potentially facing changes in climate. Rainfall over BNB supplies over two-thirds of the water to the Nile and supports a large local population living mainly on subsistence agriculture. Regional food security is sensitive to both the amount and timing of rain and is already an important political challenge that will be further complicated if scenarios of climate change are realized. In this study a simple spatial model of the timing and duration of summer rains (Kiremt) and dry season (Bega), and annual rain over the upper BNB was established from observed data between 1952 and 2004. The model was used to explore potential impacts of climate change on these rains, using a down-scaled ECHAM5/MP1-OM scenario between 2050 and 2100. Over the observed period the amount, onset and duration of Kiremt rains and rain-free Bega days have exhibited a consistent spatial pattern. The spatially averaged annual rainfall was 1490 mm of which 93% was Kiremt rain. The average Kiremt rain and number of rainy days was higher in the southwest (322 days) and decreased towards the north (136 days). Under the 2050-2100 scenario, the annual mean rainfall is predicted to increase by 6% and maintain the same spatial pattern as in the past. A larger change in annual rainfall is expected in the southwest (ca. ；130 mm) with a gradually smaller change towards the north (ca. ；70 mm). Results highlight the need to account for the characteristic spatiotemporal zonation when planning water management and climate adaptation within the upper BNB. The presented simple spatial resolved models of the presence of Kiremt and annual total rainfall could be used as a baseline for such long-term planning.