Identification and prioritization of context-specific climate smart agricultural (CSA) practices in Ethiopia: a framework approach

Ethiopia’s diverse agroecological zones showcase a variety of Climate Smart Agricultural (CSA) Practices, yet the documentation and prioritization of best-bet practices have been lacking. To address this gap, this study utilized the Climate Change, Agriculture, and Food Security (CCAFS)-CSA Prioritization framework. This approach was deployed across nine key agro-ecologies in Ethiopia to identify and prioritize CSA practices based on the three pillars of CSA and gender-equity considerations. By employing this participatory framework, this study successfully identified and prioritized over 200 Climate Smart Agricultural (CSA) practices within Ethiopia’s nine major agroecological zones. These practices were segmented into four main systems: crop management (40 practices), livestock management (41 practices), soil fertility management (40 practices), erosion control and water management (41 practices), and forest and agroforestry (40 practices). Notably, the results highlighted the significance of CSA practices linked to agroforestry/forestry management, rangeland/forage enhancement, exclosure strategies, and water management in addressing the goals associated with the three pillars (productivity, adaptation, mitigation) of CSA practices simultaneously. The findings also revealed that the majority of Climate Smart Agricultural (CSA) practices focused on improving productivity and enhancing adaptation to climate change. Additionally, the results demonstrated that trade-offs exist among the three pillars of CSA, emphasizing the need for integration with other practices to enhance complementarity and achieve all pillars simultaneously. Overall, this study underscores the importance of combining CSA practices of various categories to maximize their effectiveness and impact in sustainable agriculture.


Introduction
Agriculture forms the backbone of the Ethiopian economy, accounting about 36% of gross domestic product (GDP) and 66% of employment.It is deeply affected by climate change (variability), uncertainty and extremes, all of which significantly reduce the GDP (Bekana, 2018).Increasing average temperatures, changes in rainfall patterns, an increasing frequency of extreme weather events such as severe droughts and floods and shifting agricultural seasons have all been observed in different agro-ecological zone of Ethiopia (Zerssa et al 2021).
Studies indicated that Ethiopia has experienced an average temperature increase of 0.25 °C per decade, with the most notable rise observed between July to September (McSweeney et al 2009).According to McSweeney et al (2009) and MoEF Ministry of Environment and Forest (2015), the number of hot days and nights has also risen dramatically, with an increase of 20% and 40% respectively, between 1960 and 2003.This warming is linked to increased evapotranspiration and reduced soil moisture, with the central highlands experiencing the most substantial effects (MoEF Ministry of Environment and Forest 2015).Climate models predict a rise in Ethiopia's average annual temperature by 2030, ranging from 0.44 °C to 1.4 °C under a moderate emissions scenario (RCP4.5)and from 0.61 °C to 1.47 °C under a high emissions scenario (RCP8.5)(Gudoshava 2016).Both highest and lowest temperatures in Ethiopia are expected to rise by up to 1 °C by the 2030s, with CSA prioritization framework in their study.Their research, conducted in Ghana's Coastal Savannah Agroecological Zone, identified seven promising CSA practices: crop rotation, improved crop varieties, enhanced nutrient management, minimum tillage, mixed cropping, improved livestock housing, and supplementary feeding.Applying the CSA prioritization framework in India, Khatri-Chhetri et al (2017) found those farmers' preferences and willingness-to-pay for CSA technologies differed significantly based on the perceived benefits and costs of those technologies.This suggests that location-specific prioritization, considering farmers' perspectives, is crucial for successful CSA implementation in various parts of the world.

The CCAFS-CSA prioritization framework
The CCAFS-CSA Prioritization framework was adopted for identifying and prioritizing CSA practices (FAO 2010, Corner-Dolloff 2014, Campbell et al 2016, Gardezi et al 2022).The framework is a participatory approach and uses various steps/phases to guide stakeholders through the process of filtering a long list of applicable CSA practices into priority of CSA practices (Khatri-Chhetri et al 2017, Thornton et al 2017).According to Corner-Dolloff (2014), the approach employed three major phases/steps including i) collect/ conduct long list of CSA practices, assess/characterize the long-listed CSA practices based on productivity, adaptation, mitigation, and gender equity, as well as social-inclusion indicators), ii) identify top CSA practices (select shortlisted CSA practices based on scores, assess trade-offs among the three goals of CSA practices), and iii) conduct cost-benefit analysis of the selected CSA practices.Each step was driven by the combination of literature review and experts' knowledge gathered from various disciplines.Accordingly, based on their experience and field of specialization, 25 participants were invited from various national institutions (including public universities e.g.Haramaya University, Ethiopian Institute of Agricultural Research, Ministry of Agriculture), Regional Agricultural Research Institutes e.g., Southern Region Agricultural Research Institute, Amhara Region Agricultural Research Institute, non-governmental international research institutes e.g., the Alliance of Bioversity International and the International Center for Tropical Agriculture (CIAT)).The participants discussed the CSA practices in various agroecologies and were agreed that their results can be reported in different forms.Based on thematic areas and field of specialization, the experts were grouped into five categories (with five experts each) including (i) Crop production and management; (ii) Livestock production and management; (iii) integrated Soil Fertility Management; (iv) Erosion control and water management, and (v) and agro-forestry and forest management.The workshop participants identified and prioritized CSA practices using CCAFS CSA prioritization framework (Mwongera et al 2017, Lizarazo et al 2021) in nine Agroecological Zones (AEZ)1 of the country.In this exercise, the framework was adopted using the following specific procedures/steps (figure 2): (i) Participants were asked to understand and present the environmental/climatic issues to be addressed in each AEZ.This was done based on review literature and experts' knowledge.
(ii) Based on their knowledge and the literature, participants were asked to identify and present an exhaustive long-list of CSA options based on the environmental/ climatic issues to be addressed in each AEZs (iii) Experts developed indicators based on the literature and their own knowledge (Adimassu et al 2023a).The indicators for each CSA practice were assigned by experts to the three pillars, namely productivity and income (P), adaptation/resilience (A) and mitigation (M) and gender equity and social inclusiveness (GESI) indicators.The most important indicators related to GESI include females' control of income from practice, potential for women to benefit from increased productivity, reduces workload of female and youth, female access to cash and ability to spend it, acceptability of the practices by all religious groups, accessed by poor farmers, provides job creation opportunities.
(iv) They were asked to score CSA options against the three CSA pillars (P, A, M) and gender equity /social inclusion indicators (GES).Likert scales of between 3 and −3 were used to score CSA practices.We introduced this score range as we observed negative impacts of CSA practices in some pillars.For example, applying lime to manage acid soils increased crop yield significantly, but such application emits CO 2 and negatively affects mitigation (M).The scoring was done based on detailed discussion and consensus of group members.The scores include: If a practice has high positive effect (3), medium positive effect (2), low positive effect (1), no effect (0), low negative effect (−1), medium negative effect (−2) and high negative effect (−3).
(vi) CSA practices were ranked based on the weighted average scores.The results under each expert's group were presented in a plenary for further discussion and review to provide cross-fertilization and share experiences among the experts group.(vii) For the sake of discussion the top five CSA practices for each AEZ from each category were described.
(viii) Finally, radar graphs were used to interpret the scores and trade-offs among the three pillars of CSA practices of the top 5 CSA practices for each AEZ.
This approach has been used in various parts of the world including sub-Saharan Africa (Mwongera et al 2017, Nganga et al 2021) and Asia (Khatri-Chhetri et al 2019).For instance, Girvetz et al (2017) argued that the approach is used to design and execute CSA programs in sub-Saharan Africa countries.The approach was also used to prioritize and target context-specific investments in CSA practices in Mali (Andrieuu et al. 2017) and Western Kenya (Mwongera et al 2017).The approach was also used to facilitate cost benefit analysis of CSA practices in Ghana (Nganga et al 2021) and perceived effectiveness of CSA technologies and their scaling potential in India (Das et al 2022).

Results and discussion
3.1.CSA practices in the dry kolla agroecological zone As presented in table 2, experts prioritized the top five CSA practices suitable for Dry Kolla AEZ across each category including crop production and management, livestock production and management, soil-fertility management, erosion control and water management, and agroforestry/forestry management (Sida et al 2018).Accordingly, crop cultivar choice, using agroclimate advisory services, crop rotation with cowpeas and common beans, improved sesame varieties, and using striga resistant sorghum cultivars were selected as the top CSA practices in crop management (Mekbib 2006, Seyoum et al 2019).Rangeland improvement, selective breeding, livestock insurance, mobile-community based animal health services and supplementation were key CSA practices associated with livestock production and management in this AEZ.Since this AEZ is affected by moisture stress, most CSA practices in relation to ISFM, ECWM (Erosion Control and Water Management) and AFAF (Agro-forestry and Forestry) are related to moisture conservation practices.In this regard, using tied ridging, mulching, and leaching (salt-affected soils) practices are integrated with applying inorganic appropriate fertilizer source, rate, timing, and place (4Rs) to manage soil fertility in the Dry Kolla AEZ.Moreover, appropriate fertilizer use increases crop yield and nutrient-use efficiency (Xie et al 2023).
As shown in table 2, CSA practices related to water harvesting and water management (water storage dams, shallow wells, level fanya juu with trench and spate irrigation) were selected as the top five practices in the dry Kolla parts of the country.Studies in Eastern Ethiopia revealed that households harvesting rainwater had better nutrition and income compared with households without water harvesting (Mume 2014).Similarly, promoting agroforestry practices (particularly, Silvo-pasture, parkland, and fodder bank); assisted natural regeneration; using drought tolerant trees/shrub species; promoting management, processing and proper utilization techniques (Prosopis juliflora), and using moisture conservation practices (mulching, hydrogel) improved productivity, enhanced adaptation, reduced GHG emissions and sequestered carbon at the same time in Dry Kolla AEZs of Ethiopia.Hence, these practices have complementarity effects on the three pillars of CSA practices.Combining the CSA practices from the five categories brings various possible packages for targeted AEZs and different types of farmers.
Table 2 also presents the average scores of the three CSA pillars (productivity, adaptation, and mitigation) across the five categories in the Dry Kolla AEZ.The table showed variation in the contribution of each CSA practice for productivity (P), adaptation (A) and mitigation (M).For example, the highest scores showed that CSA practices such as tied-ridging, livestock insurance, and erosion control practices increased crop productivity and enhance adaptation.CSA practices including the using agro-advisory, crop rotation, improved sesame, and striga resistant sorghum had the highest score to adaptation and the lowest to mitigation.Similarly, range land improvement and using selective breeding of livestock scored the highest score across the three CSA pillars (P, A, M).A higher score in one pillar and lower score to the other pillars shows that there are tradeoffs among the three outcomes of CSA practices (P, A and M).Overall, in dry kola AEZ, forestry and agroforestry practices had higher scores and lower trade-offs across the three pillars, suggesting that multiple benefits of the tree-based CSA approaches are important when mitigating climate risks.Besides experts' knowledge, empirical studies showed that these CSA practices are effective in these AEZs of the country.For instance, the use of several CSA practices such as tied-ridge and soil bunds/fanya juu improved soil moisture, reduced soil erosion, improved nutrient use efficiency (Araya and Stroosnijder 2010) and profitable for small-scale farmers with NPV (Net Present Value) of US$ 2,500 per hectare (Adimassu 2023b).Similarly, the use of Bench terracing reduces soil erosion, increases cultivable area for crop and generates up to US$5,847 per ha NPV in Ethiopia (Adimassu et al 2023b).In general this study showed that these practices not only improve productivity but also enhance adaptation to climate risks and reduce greenhouse gas emissions.Combining practices from different categories offers customizable solutions for diverse farm types within the Dry Kolla AEZ (Bayu et al 2012).

CSA practices in the dry berha agro ecological zone
Dry Berha AEZ is not suitable for rain-fed crop production.Hence, experts identified CSA practices related to livestock management and water management practices (table 3).Accordingly, key CSA practices identified included: rangeland improvement, developing watering points, using drought season feeding, and increased use of off-take rates linked with feedlot and selective breeding.Using river diversion (stream diversion weir), water storage (dam and micro dam), shallow wells (washer pump, treadle pump), road water harvesting and drip irrigation increases livestock and range land productivity, enhances pastoralists' adaptation to climate change, and reduces GHG emissions in this AEZ.Using water management practices such as water harvesting, and using Table 3 presents the score of the three CSA pillars among livestock management and water-managementrelated CSA practices in the Dry Berha AEZ.Overall, CSA practices in Dry Berha AEZ contribute significantly to the adaptation (A) pillar of CSA.Looking into the specific CSA practices, rangeland improvement and developing watering points ranked highest in all three CSA pillars (P, A, M) implying that these practices are critical for achieving productivity, adaptation, and mitigation co-benefits in this AEZ.However, using droughtseason feed storage, increasing off-take rate linked with feedlot, and selective breeding of livestock ranked highest in P and A. Similarly, empirical evidence showed that most water-management-related CSA practices such as river diversion, using water storage, shallow wells, road water harvesting and using drip irrigation ranked highest for boosting productivity and adaptation (Teshome et al 2010, Assefa et al 2019, Ejigu 2021).Due to Berha AEZ's limitations for crop production and associated Climate-Smart Agriculture (CSA) practices, only livestock management and erosion control/water management practices were evaluated in this exercise.

CSA practices in the moist weyna dega agroecological zone
The Moist Weyna Dega AEZ is one of the most important agricultural zones, mainly with teff, maize, wheat, and pulses.The most important constraints in this area include soil erosion, nutrient depletion, water lodging, feed shortage, deforestation, over-grazing and pests and disease (table 4).
Growing crops using residual moisture, introducing insect tolerant verities, using Integrated Pest Management, and using rust-resistant varieties were the most important CSA practices to increase productivity/ income, enhance adaptation and contribute to mitigating climate-change impacts.Using cross-bred cows, improved forage development, intensification, and diversification of forage crops, promoting low-GHGemitting animals and precision feeding (stall feeding) are the top CSA practices.Using integrated soil nutrient management (organic (compost/vermin-compost+ inorganic 4R), at the right, time and place, biochar with inorganic fertilizer (4R), crop residue mulching + 4R, using well managed inorganic fertilizer (4R) and applying lime integrated with inorganic fertilizer (4R) in acid soils can increase crop productivity/income, enhance adaptation to climate change and mitigate its effects in AEZ crop production systems.Using bench terrace, controlled grazing, graded soil bunds with grass, graded fanya juu with grass and sub-soiling improved the three pillars of CSA practices (Adimassu et al 2017).Promoting and planting fast-growing tree species as woodlots and homesteads; using agroforestry practices (homestead, parkland, farm boundary, fodder bank), producing/using native tree species quality seedlings; protecting existing natural forest through Participatory Forest Management (PFM); and using indigenous knowledge and skills for propagation and management tree/shrub species are the most important CSA practices that increase productivity/income, enhance adaptation and improve mitigating capacity of agro-forestry and forest production system in the Moist Weyna Dega AEZ (Mekonnen et al 2021).
As shown in table 4, experts scored the highest value for P in most of CSA practices including using residual moisture; cross breeding; improved forage development; ISFM (compost/vermicompost + 4R; biochar+4R); crop residue mulching +4R; bench terracing, controlled grazing, and sub-soiling.Similarly, experts scored the highest value for all the tree CSA pillars (P, A, M) to all CSA practices in agroforestry/forestry management category (table 4).This shows that CSA practices related to forestry and agroforestry have no tradeoff effect within the three pillars of CSA practices.Previous research on CSA practices prioritized in this AEZs such as bench terrace and fanya juu are reduced soil erosion, increased cultivable area, improved land productivity and profitable when properly designed and implemented (Subhatu et al 2018).A study in Anjeni landscape of Northwestern Ethiopia showed that bench terracing generated US$1,542 per ha in 30 years period with an IRR of 300% (Adgo et al 2013, Tesfaye et al 2016).Studies also showed that CSA practices such as conservation agriculture and intercropping of cereals (e.g.sorghum) and pulses (e.g. common bean) reduced fertilizer costs and increased crop productivity and profitability with NPV of US$6,760 per ha (Adimassu et al 2023b).Using ISFM (organic fertilizer such as compost/vermicompost + 4R); crop residue mulch+4R; managed inorganic fertilization (4R); compost/vermin-compost and biofertilizers (inoculants) improve soil fertility and hence increase the three pillars of CSA practices in relation with ISFM practices.Similarly, using agro-forestry practices, fast growing trees; indigenous knowledge and skills, non-timber forest products (NTFPS) (e.g., gum, resin, wild edible fruits and lowland bamboo), and exclosure with stall feeding improves productivity of trees/ shrubs, improve animal feed availability, enhance adaptation, increase carbon sequestration and reduce GHG emissions in the Moist Koll AEZ (Mekuria et al 2007, Mekuria et al 2011, Mekuria and Aynekulu 2013).
As shown in table 5, using FYM; compost/vermicompost with 4R; hillside terracing with grass; controlled grazing; hand-dug wells; solar-based drip irrigation; conservation agriculture; agroforestry and fast-growing tree species satisfy productivity (P) increments and adaptation (A) enhancement.Agroforestry and bench terracing with grass as animal feed increases the three pillars of CSA at the same time (table 5).The study shows tradeoffs among the three pillars in most CSA practices except in exclosure and agroforestry practices.In general, some of these CSA practices were tested and verified by researchers in the country.For example, combined applications of vermicompost and inorganic NPK gave the highest potato yield and net economic benefit in Dire Dawa as compared to vermicompost and NPK only (Mengistu et al 2017).A study in the SNNP region of Ethiopia showed that hillside terracing reduced soil erosion, and increased vegetation cover and crop yield (Wolka 2014).

CSA practices in wet weyna dega agroecological zone
This AEZ is the best zone for agricultural activity, with main crops of teff, maize, wheat, and pulses.Severe soil erosion, deforestation, vertisol water-logging, and crop / animal pests and diseases are the main agricultural production constraints.Experts identified inter-cropping maize with climbing legumes, using coffee-berry disease (CBD) resistant varieties (e.g., Aba Buna), concentrated liming on acid soils, installing a broad-bed furrow (BBF) Vertisols drainage system for wheat production, and using agroclimate advisory services as the top 5 CSA practices for crop production.Intensifying and diversifying forage, using cross breeding, introducing community-based animal health service, precision feeding (stall feeding) and using low GHG-emitting animals such as small ruminants and poultry are the most important CSA practices in livestock management, based on experts' knowledge.Using FYM and inorganic fertilization, Biochar and 4R, drainage with 4R, Gypsum with 4R, and applying FYM are CSA practices related to ISFM practices to increase agricultural productivity and enhance farmers' adaptation to soil fertility decline.
The top-five CSA practices for controlling soil erosion and more effectively managing water include bench terracing; controlled grazing; graded soil bund with grasses; graded fanyaa juu with grass, and sub-soiling to break the hard plough pan.Similarly, adopting agro-forestry practices; introducing rapid propagation and multiplication techniques (e.g.; tissue culture; clonal forestry and forest biotechnology); afforestation/ reforestation with fast-growing tree species; and sustainable forest management options, including applying PFM and exclosure are CSA practices that can improve productivity of agroforestry and forestry production and sequester GHGs in above-and below-ground biomass (table 6).
The contribution of various CSA practices in the Wet Weyna Dega AEZs across the five categories to improve productivity (P), adaptation (A) and mitigation (M) are presented in table 6.All CSA practices under agroforestry and Forest management category including agroforestry, rapid propagation/multiplication techniques, afforestation/re-afforestation, sustainable and participatory forest management (PFM) and exclosure addressed the three pillars of CSA practices (table 6).Similarly, intensifying and diversifying forage crops addresses the three pillars of CSA practices because they improve livestock productivity, enhance adaptation to feed shortage and reduce GHG emissions at the same time (Menghistu et al 2021).This indicates that if properly managed it is possible to reduce GHG emission from livestock production in Ethiopia (Ayele et al 2014).In essence, Climate-Smart Agriculture (CSA) practices like intensifying forage crops and effective forest management cover all three pillars of CSA -productivity, adaptation, and mitigation.By integrating these practices, solutions for addressing agricultural hurdles in the Wet Weyna Dega region can be established while fostering sustainability.Experts identified integrated soil-fertility management practices to improve soil fertility and increase crop yield.These CSA practices include tie-ridging with ISFM practices (organic + inorganic fertilization), tie-ridging with mulching and 4R, ISFM (organic + inorganic fertilization), biochar+4R and mulch+4R.Exclosure, conservation bench terracing, level soil bunds, level fanya juu and hillside terracing with grass are the top five CSA practices to control soil erosion and manage agricultural water.Agroforestry practices, fast-growing tree species as wood lots, managing exclosure, alley cropping and using drought-tolerant trees improves agroforestry and forestry management.
The result also shows that agroforestry practices and exclosure simultaneously increase productivity, enhance adaptation, and reduce GHG emissions as reported by Lemenih and Kassa (2014).Other CSA practices such as the use of tie-ridging with ISFM, level soil bund, hillside terrace with grass, conservation bench terracing also improved productivity and adaptation (Mekuria et al 2007, Mathewos andMamo 2023) and land profitability (Meaza et al 2016, Mesfin et al 2018) in many parts of the country.

CSA practices in moist dega agroecological zone
The moist Dega AEZ covers about 4.31% of the county and it is a zone of high agricultural activity with barley, wheat, and pulses as main crops.Soil erosion; deforestation; overgrazing; soil crusting; soil nutrient depletion; feed shortage; low agricultural productivity; crop, and animal pests/diseases are the main constraints of Moist Dega AEZ (table 8).Experts identified using bio-inoculants; optimal variety selection (e.g.improved potato; improved beans (Faba bean/Field pea)); using agroclimatic advisory services (mobile based application); crop rotation (cereal/potato versus legume) (Tesfamichael and Reddy 1996), and using fallow for boosting productivity and mitigation under ongoing climate and environmental changes.Intensifying and diversifying fruit and forage crops; introducing community-based animal health services; promoting low-GHG-emitting animals; using silvopastoral systems, and cross breeding are the top CSA practices under livestock management (Abegaz et al 2014, Abera 2019).Similarly, managed inorganic fertilization (4R), Biochar + 4R, Liming + 4R, Compost/vermicompost, green manure can be used to improve soil fertility and improve crop productivity in this AEZ.In order to control soil erosion and better manage water resources, using BBF; graded soil bund with grass; graded fanya juu with grass; flood-water diversion, and sub-soiling can reduce land degradation and improve water-use efficiency.Agro-forestry practices; introducing rapid propagation and multiplication; afforestation/reforestation with fast-growing tree species; and sustainable forest management option including PFM and exclosure, all improve the three CSA pillars in agroforestry and forestry production system.
The result shows that most CSA practices in Agroforestry/forestry management category including agroforestry practices, using rapid propagation and multiplication, afforestation, and using PFM approaches improved the three pillars of CSA practices (P, A and M).In addition, intensifying and diversifying forage crops increases P, enhances A, and reduces GHG emissions from livestock production.Several CSA practices increase P and enhanced A. These practices include using bio-inoculant, variety selection, agroclimatic advisory, community-based animal health service, managed inorganic fertilization (4R), and using BBF and a broad-bed maker (BBM).Wubie (2015) reported that the use of BBM is low-cost and appropriate technology that drains excess water from the vertisols and improved yield of Wheat in the Vertisols of Etiopian highlands.Moreover, studies in Ethiopia showed that application of biochar in acidic soils significantly improved crop yield through improved total nitrogen, soil organic carbon, available reduction and exchangeable acidity (Berihun et al 2017).

CSA practices in wet dega agroecological zone
This zone covers about 3% of Ethiopia's land mass and is a zone of high agricultural activity with barley, wheat and pulses as main crops growing in two seasons: Belg (Short rain season) and Meher (main season).High rainfall reliability, soil erosion, and water lodging in vertisols are the key production constraints.Experts identified and prioritized key CSA practices in the five categories (table 9).Water-logging tolerant crops, (e.g., cultivated Oat), traditional ridging (locally called Shurube), using acid tolerant crops, growing crops using residual moisture, and using a Broad Bed maker (BBM) are the most important CSA practices related to crop management in Wet Dega AEZ.Intensifying and diversifying forage crops; consulting community-based animal health services; promoting low-GHG-emitting animals; establishing silvopastoral-integrated forestry; integrating fodder species production, and cross breeding (Adimassu and Tamene 2021, Tamene et al 2021).The using organic + inorganic fertilization with drainage, organic + inorganic fertilization, biochar+4R, residue incorporation + 4R and using lime +4R are the top-five CSA practices to enhance soil fertility and crop productivity.Experts identified using BBM, graded soil bund/graded fanya juu with grass, bench terrace and conservation agriculture are identified as key CSA practices to control soil erosion and manage agricultural water.Similarly, using agroforestry practices, assisted natural regeneration (ANR) and fast-growing tree species are CSA practices in forest management category.Agroforestry practices for assisted natural regeneration (ANR); intensifying and diversifying forage crops, planting waterlogged tolerant crop varieties and traditional ridging (e.g., 'shurubee') can all address P, A and M (table 9).Using acid-tolerant crops; consulting community-based animal health services; growing crops under residual moisture; BBF; ISFM (organic + inorganic fertilization); using non-timber forest products and planting fast-growing tree/shrub species could increase productivity and enhance adaptation to climate change.

CSA practices in wet kolla agroecological zone
The Wet Kolla AEZ covers about 1.5% of the Ethiopian landmass and is suitable for citrus, cotton, maize, taro with two cropping seasons.Soil erosion, soil fertility depletion (due to nutrient fixation), water-logging and disease/insect pests are the main challenges for agricultural production.According to experts' knowledge, appropriate fertilizer application methods (such as microdosing); intercropping; planting acid-tolerant crops; using agroclimatic advisory services and taking out crop insurance are the top CSA practices in crop management (table 10).Community-based animal health services, selective breeding, supplementation of minerals and vitamins, pastureland improvement and crop residue treatment (e.g., urea treatment) improves animal productivity, farmers' adaptation and contributes to reducing GHG emissions.Using organic fertilizer (compost/vermicompost) + inorganic fertilization (4R), crop residue mulch+4R, organic fertilizer (compost/ vermicompost), bio-fertilizers (inoculants) and FYM are CSA practices related to integrated soil fertility management.Again, alley cropping, conservation tillage, BBF, graded soil bunds with grass and graded fanya juu with grass are key CSA practices for controlling soil erosion and manage agricultural water.Similarly, agroforestry practices (agro-silviculture, fruit-based agroforestry), promotion of fast growing trees in the homestead, farm boundary and buffer lands, promote the using PFM, NTFPs (e.g. using gum, resin, wild edible fruits and lowland bamboo) and exclosure with stall feeding are CSA practices in forest management category (Abebe andBongers 2012, Balana et al 2012).
Agroforestry practices (such as agrosilviculture, alley cropping), conservation tillage and using BBF to manage vertisols are key CSA practices that increase productivity, enhance adaptation and reduce GHG emissions (table 10).Applying fertilizer using microdosing3 , using integrated fertility management (Organic + inorganic at 4R) can address the two pillars (productivity, adaptation) of CSA practices.Moreover, studies have demonstrated the economic viability of these practices.Adimassu et al (2023b) conducted a cost-benefit analysis revealing that compost and biochar use increased crop production and generated a net present value (NPV) of US$3110 and US$1883 per hectare.

Tradeoff among the three pillars of CSA practices
Climate-smart agriculture encompasses three pillars: productivity (P), adaptation (A), and mitigation (M).The concept of trade-offs within these pillars highlights that prioritizing practices related to one pillar may potentially impact the effectiveness or success of another.This dynamic interplay emphasizes the need for holistic approaches that balance the goals of enhancing productivity, building resilience to climate change, and reducing greenhouse gas emissions.Achieving a sustainable agricultural system requires careful consideration and integration of strategies that address the interconnected nature of these pillars to optimize outcomes while minimizing negative trade-offs.For example, increasing productivity through intensive farming practices may lead to higher greenhouse gas emissions, compromising the mitigation pillar.Hence, balancing these trade-offs is crucial for implementing effective climate-smart agricultural practices.As shown in figure 3(A), productivity is ranked highest in ISFM practices suggests that CSA practice related to ISFM is important to maximizing crop yield.The CSA practices where the three pillars coincide at its maximum value were CSA practices related to livestock management practices (e.g.rangeland management) and forest and agroforestry management (Duguma 2013).This implies that these practices synergized and maximized the three pillars simultaneously without trade-offs among the pillars.As shown in the figure, productivity and adaptation are equally important to some CSA practices, such as erosion control and water management.Figure 3(B) resents the combined pillars across various AEZs of the country.The highest average scores of adaptation were recorded in almost all of the AEZs implying that adaptation as CSA pillar is the most important pillar of CSA practices.Similarly, the lowest average scores were recorded for mitigation pillar for each AEZ.The results in figure (A) and (B) imply that there exists trade-off among the three CSA pillars for most of CSA categories across major AEZs of the county.A study showed the potential trade-offs between economic and environmental objectives of CSA practices in Malawi (Schaafsma et al 2018).Another study in Kenya with selected CSA practices indicated that the productivity pillar to be the best performing CSA pillar synergistically while trade-offs to occur across CSA pillars (Ogola and Ouko 2021).When considering the three pillars of CSA (Climate-Smart Agriculture) -productivity, adaptation, and mitigation -there exists a delicate balance that requires thoughtful tradeoffs.It's crucial to prioritize enhancing agricultural productivity to ensure food security and economic stability while also incorporating adaptation strategies to cope with the impacts of climate change.Additionally, focusing on mitigation efforts to reduce greenhouse gas emissions is equally important for long-term sustainability (Adgo et al 2013).Striking a harmonious balance among these pillars involves implementing practices that boost productivity, increase resilience to climate variability, and minimize environmental impact.By carefully navigating and optimizing these tradeoffs, agricultural systems can become more sustainable, efficient, and resilient in the face of a changing climate.

Limitation of the study
One key limitation of the CSA-PF approach is its incompatibility with statistical testing.This paper consequently lacks any statistical analysis.Additionally, the study relies solely on expert knowledge and literature review, omitting the valuable perspective of farmers.

Conclusion
The use of CCAFs-CSA Prioritization framework is appropriate method to identify and prioritize CSA practices using experts' knowledge and literature review.Through this framework, more than 200 context-specific and best-bet CSA practices were generated.The prioritization exercise has provided information about the contributions of the various CSA practices related to the three CSA pillars (productivity, adaptation, and mitigation).Moreover, this study has generated databases of CSA practices to be used for various stakeholders including farmers, researchers, development organizations and policymakers.Prioritizing CSA practices based on AEZ provides opportunities to develop context-specific CSA packages across different AEZs and farms, and farmer types.Based on the types of farms/farmers, it is possible to develop CSA packages across the various agroecologies by considering the selected CSA practices in the five categories.Since this prioritization is based on experts' knowledge at national level, it is also crucial to test and validate the CSA practices with various typologies of farmers in selected agro-ecologies.The results show that CSA practices related to agroforestry/forestry management practices, rangeland/forage improvement, and exclosure and water management addressed the goals associated with the three pillars (productivity, adaptation, mitigation) simultaneously.Hence, developing and implementing policies that promote CSA practices including agroforestry, rangeland/forage improvement exclosure and rainwater can promote CSA practice in Ethiopia.Incentivize farmers (e.g.financial support, subsidies, and access to credit) to implement site specific and best-bet CSA practices is crucial to improve productivity and enhance resilience against climate change impacts.Hence, Ethiopia can strengthen its agricultural sector's resilience to climate change, increase agricultural productivity, enhance food security, and promote sustainable development in the country through the use of CSA practices.

Figure 3 .
Figure 3. Tradeoff between the three pillars of CSA practices among the CSA categories (A) and Agro-ecological Zones (B).
Sida T S, Baudron F, Kim H and Giller K E 2018 Climate-smart agroforestry: Faidherbia albida trees buffer wheat against climatic extremes in the Central Rift Valley of Ethiopia Agric.For.Meteorol.248 339-47 Subhatu A, Speranza C I, Zeleke G, Roth V, Lemann T,Herweg K and Hurni H 2018  Interrelationships between terrace development, topography, soil erosion, and soil dislocation by tillage in Minchet Catchment, Ethiopian Highlands Land degradation & development 29 3584-94 Tamene L, Abera W and Adimassu Z 2021 From buffet to best-fits: co-identifying and prioritizing best-bet CSA practices for targeting and scaling in the central highlands of Ethiopia Agriculture and Food Security (CCAFS) CCAFS activity report Wageningen (Netherlands) CGIAR research program on climate change 18 Tegene S, Terefe H, Dejene M, Tegegn G, Tena E and Ayalew A 2021 Survey of sugarcane smut (Sporisorium scitamineum) and association of factors influencing disease epidemics in sugarcane plantations of Ethiopia .Tropical Plant Pathology 46 393-405 Tesfamichael N and Reddy M S 1996 Maize/bean intercropping effects on component yield, land use efficiency and net-returns at Awassa and Melkassa Proc. of the 1st Conf. of the Agronomy and Crop Physiology Society of Ethiopia.Addis Ababa, Ethiopia 51-5 Tesfaye A, Brouwer R, Van der Zaag P and Negatu W 2016 Assessing the costs and benefits of improved land management practices in three watershed areas in Ethiopia International Soil and Water Conservation Research 4 20-9 Tesfaye W, Blalock G and Tirivayi N 2020 Climate -smart innovations and rural poverty in ethiopia: exploring impacts and pathways American Journal of Agricultural Economics 103 878-99 Teshome A, Adgo E and Mati B 2010 Impact of water harvesting ponds on household incomes and rural livelihoods in Minjar Shenkora district of Ethiopia Ecohydrol.Hydrobiol.10 315-32 Thornton P, Rosenstoc T, Lamann C, Bell P, Förch W, Henderson B and Herrero M 2017 Climate-smart agriculture options in mixed croplivestock systems in Africa south of the ahara S Climate Smart Agriculture: Building Resilience to Climate Change ed D Zilberman et al (Springer) Thornton P K, Whitbread A, Baedeker T, Cairns J, Claessens L, Baethgen W and Keating B 2018 A framework for priority-setting in Climate-Smart Agriculture research Agric.Syst.167 161-75 Tovihoudji P G, Akponikpè P I, Agbossou E K, Bertin P and Bielders C L 2017 Fertilizer microdosing enhances maize yields but may exacerbate nutrient mining in maize cropping systems in northern Benin Field crops research 213 130-42 USAID 2012 Climate change adaptation in Ethiopia https://climatelinks.org/sites/default/files/asset/document/ethiopia_adaptation_ fact_sheet_jan2012.pdfUSAID 2016 Climate change risk profile-Ethiopia.Fact Sheet https://climatelinks.org/sites/default/files/asset/document/2016% 20CRM%20Factsheet%20-%20Ethiopia_use%20this.pdfWolka K 2014 Effect of soil and water conservation measures and challenges for its adoption: Ethiopia in focus J. Environ.Sci.Technol.7 185-99 Wubie A 2015 Review on vertisol management for the improvement of crop productivity in Ethiopia Journal of Biology, Agriculture and Healthcare 512 92-103 Xie H, Dile Y T, Ringler C, Srinivasan R and Worqlul A 2023 Toward a better understanding of the environmental impacts of expanding farmer-led irrigation in Sub-Saharan Africa: an exploratory assessment of irrigation-induced risk of nutrient water pollution in Ethiopia Environmental Research Communications 5 065001 Zegeye H 2018 Climate change in Ethiopia: impacts, mitigation, and adaptation International Journal of Research in Environmental Studies 5 18-35 Zerssa G, Feyssa D, Kim D G and Eichler-Löbermann B 2021 Challenges of smallholder farming in Ethiopia and opportunities by adopting climate-smart agriculture Agriculture 11 192 Zougmore R B, Läderach P and Campbell B M 2021 Transforming food systems in Africa under climate change pressure: role of climatesmart agriculture Sustainability 13 4305

Table 1 .
Hurni et al (2016) 9 (out of the 15) major agroecological zones (AEZs) where CSA practices are identified and prioritized.Source:Hurni et al (2016).LGP: length of growing period.This zone is situated largely in the western parts of Ethiopia.It is suitable for maize, taro, citrus and cotton.Two cropping seasons.The soil is deeply weathered red clay loam to red clay, and on flat areas, black heavy clay.
Good zone of agricultural activity with teff (Eragrostis tef), maize (Zea mays) and wheat (Triticum aestivum) are the main crops grown in this AEZ.Sorghum in drier areas.Enset (Ensete ventricosum) and nug seed (Guizotia abyssinica) in the western highlands, and Khat (Catha edulis) in the eastern highlands.This zone is suitable for sorghum, teff, cotton and finger millet (Eleusine corcana).The soil is deeply weathered red clay loam to red clay and on flat areas, black heavy clay.The red soil is leaching and

Table 2 .
Five top CSA practices related to the five categories in dry kolla agro-ecological zone: based on experts' knowledge.water can support effective rangeland/forage development and cultivation of crops such as sorghum and millet (Adimassu et al 2021, Bricca et al 2019).

Table 3 .
Five top CSA practices related to the five categories in dry berha agro-ecological zones: experts' knowledge.Note: Values in the [parenthesis are average-weighted scores of the three pillars.

Table 4 .
(Abate and Alemayehu 2018)ated to the five categories in moist weyna dega AEZs experts' knowledge.Note: 4R: Right source, right amount, right place and right time.Values in the [parenthesis are average-weighted scores of the three pillars.3.4.CSA practices in the moist kolla agroecological zoneThe moist Kolla AEZ is mostly situated in the western parts of Ethiopia.It is suitable for sorghum, teff, cotton and finger millet (dagussa).According to experts, using farmyard manure (FYM), intercropping of cereals with pulses, agroclimatic advisory, crop insurance, seed treatments were the five top CSA practices to increase productivity/income, enhance adaptation and reduce GHG emissions/sequester carbon in crop production management(Abate and Alemayehu 2018).Community based animal health services; selective animal breeding, supplementations of feed, pastureland improvement and crop residue treatment can increase productivity of livestock, enhance adaptation, and contribute to mitigating climate-change impacts in Moist Kolla AEZ of the country (table5).

Table 5 .
Five top CSA practices related to the five categories in moist kolla agro-ecological zones: experts' knowledge.Right source, right amount, right place and right time.Values in the parenthesis are weighted scores of the CSA pillars.

Table 6 .
Five top CSA practices related to the five categories in wet weyna dega agro-ecological zones: experts' knowledge.Right source, right amount, right place and right time.Values in the parenthesis are average-weighted scores of the CSA pillars.CSA practices in the dry weyna dega agroecological zone The Dry Weyna Dega AEZ has a very short rainy season with low but intense rainfall.Main crops are wheat and barley.Severe soil degradation (soil erosion, nutrient depletion, and deforestation) and over-grazing are the main production problems in this AEZ.As shown in table 7, several CSA practices suitable for this AEZ are identified by experts across five categories.Similarly, appropriate crop choice, planting striga tolerant/resistant varieties, adjusting planting date and using agroclimatic advisory services are important CSA practices in relation to crop management.Experts prioritized five CSA practices to manage livestock including using improved forage development; fodder bank development through exclosure; promoting low GHG-emitting animals such as poultry; using community-based animal health services, and selective breeding of livestock.

Table 7 .
Five top CSA practices related to the five categories in dry weyna dega agro-ecological zone: experts' knowledge.Right source, right amount, right place and right time.Values in the parenthesis are average-weighted scores of the CSA pillars.

Table 8 .
Five top CSA practices related to the five categories in moist dega agro-ecological zones: experts' knowledge.Right source, right amount, right place and right time.Values in the parenthesis are average-weighted scores of the CSA pillars.

Table 9 .
Five top CSA practices related to the five categories in wet dega agro-ecological zones: experts' knowledge.
Note: 4R: Right source, right amount, right place and right time, BBM: Broad Bed maker, BBF: Broad Bed Furrow, PFM: Participatory Forest Management, NTFPs: None-timber forest products.Values in the parenthesis are averageweighted scores of the three pillars.

Table 10 .
Five top CSA practices related to the five categories in wet kolla agro-ecological zone: experts' knowledge.Right source, right amount, right place and right time, BBM: Broad Bed maker, BBF: Broad Bed Furrow, PFM: Participatory Forest Management, NTFPs: None-timber forest products.Values in the parenthesis are averageweighted scores of the three pillars.