Review of agricultural production systems in eastern Africa in relation to food and nutrition security and climate change

The goal of this paper is to provide a unified resource for Eritrea, Djibouti, Somaliland, Somalia, Ethiopia, Kenya, Uganda, Rwanda and Tanzania. For each country the review covers the topics of livestock production systems and agroecological zones, food and nutrition security, climate change, greenhouse gas (GHG) emissions and climate-smart agriculture (CSA) with a focus on the role of, or impact on, livestock systems. Each of these topics is broad and many excellent studies and reviews have been produced covering these topics either at the country level or for the entire East Africa region. It is the goal of this paper to provide an accessible introduction to these topics and to direct readers to the resources that exist for gathering detailed information on livestock production, food nutrition and security, climate change, GHG emissions and climate-smart livestock production in each country

Temporal and spatial variability of rainfall distribution and evapotranspiration across altitudinal gradient in the Bilate River Watershed, Southern Ethiopia

Rainfall and evapotranspiration are the two major climatic factors affecting agricultural production. This study examined the extent and nature of rainfall variability from measured data while estimation of evapotranspiration was made from recorded weather data. Analysis of rainfall variability is made by the rainfall anomaly index, coefficient of variance and precipitation concentration index. The FAO-56 reference ET (ETo) approach was used to determine the amount of evapotranspiration. Estimation of the onset, end of growing season and length of growing period was done using Instat software. The results show that mean annual rainfall of the upper (2307 m.a.s.l), middle (1772 m.a.s.l) and lower (1361 m.a.s.l) altitude zones of the watershed are in the order of 1100, 1070 and 785 mm with CV of 12, 15 and 17% respectively. There was a high temporal anomaly in rainfall between 1980 and 2013. The wettest years recorded Rainfall Anomaly Index of +5, +6 and +8 for stations in upper, middle and lower altitude zones respectively, where the driest year recorded value is -5 in all the stations. The average onset date of rainfall for the upper zone is April 3 ± 8 days, for the middle zone April 10 ± 10 days and for the lower zone is April 11 ± 11 days with CV of 23%, 26 and 29% respectively. The average end dates of the rainy season in the upper and middle zones are October 3 ± 5 days and September 25 ± 7 days with CV 5 and 7%. The main rainy season ends earlier in the lower zone; it is on July 12 ± 10 days with CV of 14%.Keywords: Variability, days of the year (DOY), onset, end date, length of growing period (LGP

Review of policies and frameworks on climate change, agriculture, food and nutrition security in Ethiopia

Agriculture is the mainstay of Ethiopia’s economy, contributing over 50% of the gross domestic product (GDP), accounting for more than 85% of the labor force and over 90% of the foreign exchange earnings (Alemu et al. 2010). Consequently, the sector receives considerable attention from the government, investing 15% of its total budget over the decade and meeting the commitments by Africa’s heads of states to the African Union Maputo 2003 Declaration on Agriculture and Food Security (CAADP 2003). On average, crop production makes up 60% of the sector’s outputs, livestock accounts for 27%, with other sub-sectors contributing 13% of the total value of agricultural production. The sector is dominated by small-scale farmers, practicing rain-fed mixed farming using traditional technologies, characterized with low levels of input use and low productivity

Anthropogenic forcing increases the water-use efficiency of African trees

Rising atmospheric CO2 concentrations affect climate directly through radiative effects and indirectly by changing plant water-use efficiency. Under global warming scenarios these widely reported changes will have a substantial impact on future bush encroachment, crop yields, river flow and climate feedbacks. Tree-ring intrinsic water-use efficiency (iWUE) records for Africa show a 24.6% increase over the 20th century. As high iWUE can partly counterbalance projected decreases in regional precipitation, this research has important implications for those involved in water resource management and highlights the need for climate models to take physiological forcing into account.National Geographic Society - Science and Exploration Europe (grant GEFNE80-13), the Royal Geographical Society, the Quaternary Research Association, the Palaeo-Anthropological Scientific Trust, the National Research Foundation, SysTem for Analysis, Research and Training (START) and the Climate Change Consortium of Wales.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1099-14172017-05-31hb2016Mammal Research Institut

Forest soils of Ethiopian highlands : their characteristics in relation to site history : studies based on stable isotopes

Isotopic composition and nutrient contents of soils in forests, pastures and cultivated lands were studied in Menagesha and Wendo-Genet, Ethiopia, in order to determine the effects of land use changes on soil organic matter, the N cycle and the supply of other nutrients. In the Menagesha forest, which according to historical accounts was planted in the year 1434-1468, 5I3C values at > 20 cm soil depth of from -23 to -17%o and in the surface layers of from -27 to -24%o suggest that C4 grasses or crops were important components of the past vegetation. At Wendo-Genet, the 5'3C values in the topsoils of from -23 to -16%o and in the > 20 cm of from -16 to -14%o indicated more recent land use changes from grassland to forest. At Menagesha, 5I5N values shifted from -8.8%o in the litter to +6.8%o in the > 20 cm. The low 5I5N in the litter (-3%o) and topsoils (0%o) suggest a closed N cycle at Menagesha. At Wendo-Genet, the high 5I5N (3.4-9.8%o) and low total N concentrations suggests a more open N cycle with greater N losses. At Menagesha, the variation in soil nutrient contents followed the patterns of %C and %N. At the mid-altitudes, where there had been undisturbed forest cover for > 500 years, %N and %C were higher and the surface layers showed high accumulation of Ca and S. The strong relation between %C and CEC, suggests that organic matter increases the nutrient retention capacity of these soils. Exchangeable and total Ca were strongly related (r2 = 0.95, P < 0.001). It is suggested that the presence of forests in this otherwise bare landscape leads to interception of base cations in dust, which can help to sustain a productive forest. The studies show that the approach to combine stable isotopes with nutrient elements is especially useful when studying the chemical properties of forest soils in relation to site history. They also show that productive forests with a high soil organic matter content can be established on fairly steep slopes in the Ethiopian highlands

Physiological, Biochemical, and Growth Parameters of Fogera Cattle Calves to Heat Stress during Different Seasons in Sub-Humid Part of Ethiopia

Fogera cattle are among indigenous breeds of cattle in the northern part of Ethiopia. However, their response to heat stress (HS) under different seasonal variations has not been well investigated. This study was aimed to determine physiological, hematological, biochemical, and growth parameters of Fogera cattle calves to HS during dry season, short rainy, and long rainy. A total of 72 calves (24 for each season) that were 6 months of age with an equal number of males and females were evaluated for physiological, hematological, biochemical, and growth parameters. Daily ambient temperature (AT) and relative humidity (RH) were recorded two times per day during the study periods from which the daily average temperature–humidity index (THI) was calculated. The study revealed higher AT and THI during dry and short seasons while higher RH was observed during the long rainy season. Physiological parameters except rectal temperature were affected by the seasons. Hematological parameters were also affected by season except for packed cell volume. Biochemical and growth parameters were also significantly affected by the seasons. THI was positively related with physiological but negatively with growth parameters. Thus, the THI value of 66 can be considered as optimum for high weight gain and normal physiological response to HS in Fogera cattle calves under their current production system

Urban church forests for local temperature regulation: Implications the role of managing and incorporating urban green space in urban planning

The global surface temperature shows an increment of 0.50.1C per decade and 1.050.3C per century from 1880-2014 with greater increases in cities than non-urban areas. Global communities are shifting towards urbanization due to various factors. Urbanization has caused lack of stable condition for dwellers due to environmental and anthropogenic factors such as land cover changes. Urban temperature rising is the main factors hindering urban dwellers at global level due to insufficient green areas. Social institutions are playing important role in urban greening and urban climate regulation. Ethiopian Orthodox Tewahido Church has long history in indigenous trees biodiversity conservation that plays largely greening role in urban and rural parts of the country. However, there is a research gap in Ethiopia regarding the role of urban green area in the church yards in regulating urban temperature and microclimate change. Therefore, the study evaluated the role of church managed forests in Addis Ababa in regulating surface temperature. Surface temperature inside four church forests at a buffer radius of 0–50 m, 50–100 m, 100–200 m and 200–500 m estimated using Landsat image thermal band 6 of 1986, 2000 and 2010 and ground measurement by ambient thermometer at 10:00 am, 12:30 am and 3:00 pm local time. The ground measurement was done in order to validate satellite image analysis. Plant species diversity, DBH, H, HC, BH and BA was measured. There were 1167 trees in the four studied churches. The mean temperatures of the studied sites were 22.50.1, 23.250.2, 240.6, 24.61.1 and 25.52.2C on site,0–50 m, 50–100 m, 100–200m and 200–500 m respectively for 1986 images; 23.20.5, 23.31.0, 24.32.1, 24.82.2 and 25.51.8C on site, 0-50 m, 50–100 m, 100–200 m and 200–500 m respectively for 2000 images and 23.20.3, 23.270.2, 23.71.6, 241.4 and 24.71.3C on site, 0–50 m, 50–100 m, 100–200 m and 200–500 m respectively for 2010 images. The result illustrated a significant influence of green area on urban temperature in the buffering radius and implies the possibility of regulating urban temperature by planning urban green area in appropriate radius intervals. The study indicated that church forests in particular, social institution and urban green area in general have significant role in urban temperature regulation

Large paleoenvironmental insights from tiny molecules that "don't do anything": lessons from French and Ethiopian deposits.

International audiencePaleoenvironmental records provide insights into fundamental questions about structural changes in past human populations. Three problems with proxies lower the resolution of such records: 1) spatio-temporal discontinuity, 2) reflecting multiple factors at once, and 3) decomposition beyond recognition. Analyses of specific lipid molecules that "don't do anything" in soils and sediments are overcoming these obstacles. These are products of decomposition that resist further chemical change. Stable hydrogen isotopic compositions (δD) of molecules with long carbon chains in fatty acids and alkanes are providing records of paleoprecipitation. The records' accuracy may be undermined by changes in cover of their plant sources. Correcting for changes in C3 and C4 plant cover did not alter δD trends from fatty acids in Ethiopian soil sections and reflected shifts in precipitation amounts. In contrast, δD values of specific alkanes in soils along an elevation transect of Ethiopian agricultural stations did not reflect precipitation trends unless differences in C3 and C4 plant cover were accounted for. Pentacyclic triterpene methyl ethers (PTMEs) include potential biomarkers for specific plant types. The PTME miliacin is specific to broomcorn millet in the French Lake Bourget area. In addition to providing precipitation inferences that are not affected by changes in plant sources, its contents in sediments provide insights into millet agriculture by Bronze Age peoples where artifacts such as seeds have decomposed. Another PTME, crusgallin, is found only in grasses and its δD values are showing greater sensitivity to changes in precipitation than fatty acids from soils near ancient Ethiopian civilizations

Palaeoenvironmental Change and the Rise and Fall D'MT and Aksum in Northern Ethiopia: How an unambiguous proxy for rainfall can improve interpretations of micromorphological and botanical data

International audienceConsidered the fourth most powerful commercial empire in the Old World during its peak, Aksum (ca. 150 BCE - 700 CE) was by far sub-Saharan Africa's most complex ancient polity. It was preceded in the Tigray Plateau of Ethiopia and Eritrea by a less studied entity, D'MT (ca. 800 - 400 CE) that had many of the same material accoutrements connoting complexity. As the region is subject to significant spatio-temporal changes in climate and has relief that makes it highly vulnerable to erosion, it has been assumed that environmental changes played significant roles in the rise and fall of these polities. The exposed soils of the region's many ravines, promise its most ubiquitous archives of palaeoenvironmental inferences. In the absence of lakes and their archives of pollen, a combination of δ13C analyses of soil organic matter (SOM) with identification of charcoalised wood provided information about past percent biomasses of C3 and C4 plants as well as tree species for palaeovegetation records. A combination of micromorphological and elemental analyses provided insights about historical fire activity. Nonetheless, changes in these records could have been caused by climate and/or land clearing trends and thus they are an ambiguous suite of proxies. Analyses of stable hydrogen isotopic compositions (δD) of specific lipid molecules in organic matter are increasingly being used to provide unambiguous records of palaeoprecipitation for regions at tropical latitudes. The resolution of precipitation records δD values can be affected by the types of their vegetation sources, however. We analysed δD values of land plant derived fatty acids and used our carbon isotopic and elemental analyses to correct for possible effects of changes in C3 and C4 vegetation sources. The correction did not lead to any changes in trends of the δD fatty acid records. The fatty acids analysed are present in most land plants. We then analysed δD values of crusgallin, a pentacyclic triterpene methyl ether (PTME) known only to be produced by grasses and probably only C4 grasses in our study sites. Narrowing the range of possible plant sources to this extent proved the most sensitive means of detecting trends in precipitation over time. The δD records made it more possible to decipher the relative influences of precipitation and land clearing on changes in micromorphological and vegetation data, in some cases sharpening insights about the influences of human activity. Results thus far support hypotheses that the rise of both D'MT and Aksum were favored by slight increases in rainfall during an overall drying trend. At least in the hinterlands, much more marked indications of land clearing can be inferred during D'MT's emergence than Aksum's