Enhancing Adaptation to Climate Change through Conservation Farming in Ethiopia


DCG, in partnership with the Tigray Agricultural Research Institute (TARI), the Amhara Regional Agricultural Research Institute (ARARI), and Hawassa University (HU), are working to strengthen rural farmers' adaptive capacity to the effects of climate change in three regions of Ethiopia (Tigray, Amhara,and the Southern Nations, Nationalities, and People's Region- SNNPR) by testing the effects of various CF techniques on finger millet, maize, sorghum, and teff production.




The problem of food insecurity has become more intensely pronounced in recent years with the threat posed by recent trends, such as climate change, water and rainfall scarcity, as well as ecosystems and biodiversity degradation. In Sub-Saharan Africa, most rural communities are languishing in abject poverty, yet the agricultural systems being promoted there have unacceptably high environmental, economic, and social costs. Nearly 80% of the population in Sub-Saharan countries lives in rural areas with 70% of this rural population being directly dependent on agriculture for their livelihood. It is thus against this scenario and statistics that, rural farmers have to consequently adopt farming practices that conserve fragile soils and improve their fertility for improving crop production in marginal rainfall regions.

Ethiopia's climate is highly variable, and is projected to become more variable due to climate change, with the potential for increased frequency of extreme weather events. Since the 1970s, the magnitude, frequency, and impacts of droughts have become more severe and drought has become the most significant and recurrent climate-related hazard affecting the country. Water is a specifically fragile resource with the frequency and intensity of drought projected to increase. Addressing long-term climate change is thus required to reduce the impacts on livelihoods and bolster major economic sectors such as agriculture, which is the mainstay of the country.

The vulnerability to climate-related hazards and food insecurity is closely linked to land degradation. About 85% of the land surface in Ethiopia is considered susceptible to moderate or severe soil degradation and erosion. In the Highlands, those problems are reducing the sustainability of agricultural production, thereby making it difficult for rural populations to meet their basic needs. Repeated ploughing to achieve fine seedbeds using maresha, the almost complete removal of crop residues after the harvest and insufficient application of manure are major contributors for soil degradation in Ethiopia. Tillage has long been used by farmers to loosen the soil, make a seedbed, and control weeds. However, not all outcomes of this practice are positive; it has been discovered that tillage operations, over time, cause a decline in soil fertility and overall productivity resulting from deterioration of soils' physical, chemical, and biological properties.

Among the solutions being floated to mitigate the impact of climate change is adapting to droughts through sustainable farming methods. Conservation farming (CF) practices hold the promise of providing both a strategy for mitigating climate change and also working as an adaptive mechanism to cope with climate change. CF is being promoted as a panacea to the production challenges, confronting rural smallholder families particularly in Sub-Saharan Africa.

In CF crops are grown using Conservation Tillage (CT) and legumes are included in rotation with other crops. Legumes fix nitrogen, improve fertility of the soil, increase crop yields and provide proteins to the family. CT involves the planting, growing and harvesting of crops with minimal disturbance to the soil surface through the use of minimum tillage, mulch tillage, ridge tillage, or no-till. Besides, CF is a system that promotes balanced application of chemical inputs (only as required for improved soil quality and healthy crop and animal production), and careful management of residues and organic wastes. CF practices emphasize maximum use of available water resources through early and timely planting, soil protection through organically fertilizing ground-cover plants, and watershed management. This reduces long term dependency on external inputs, enhances environmental management, and improves water quality and water use efficiency. Reduced tillage leads to lessened human inputs, in both time and effort. Conservation farming aims at reversing a persistent trend in many production systems of reduced infiltration capacity of soils due to compaction and crust formation and reduced water holding capacity due to oxidation of organic materials (due to excessive turning of the soil). From this perspective, conservation tillage is a form of water harvesting, where runoff is impeded and soil water is stored in the root zone of the crop. This means that conservation tillage constitutes a very interesting approach to achieve improvements in water productivity and “crop per drop" increases, and thus contribute to reversing the impacts of climate change.

Different studies conducted in several countries indicated that CF contributed to increased crop yield. An Australian study showed that CF provides more reliable yields than those achieved under conventional tillage. A Kenyan study indicated that maize grain yields varied from a lowest of 0.9 t/ha for conventional ploughing (control) during short rains in 2002 to highest average of 4.3 t/ha in ripper + fertilizer treatment in long rains. The highest average yield per season of 2.5 t/ha was achieved with ripping combined with fertilizer compared to conventional tillage practice of 2.0 t/ha.

CF, in its current manifestation, was introduced three decades ago and is currently being practiced on more than a hundred million hectares of land worldwide in more than fifty countries. In Zimbabwe, there was a 230 percent increase in the land on which CF was being practiced between the 2004/5 and 2005/6 seasons, and CF led to higher yields for maize, sorghum, soybean and cowpeas. In Zambia, farmers practicing CF on average produced about 100% more maize and 60% more cotton per hectare than did farmers practicing conventional ox plough tillage. CF with ox-drawn rippers likewise holds the potential to outperform conventional ox ploughing, offering higher returns to peak season labour and to land. CF is especially more beneficial for farmers with limited access to oxen draught power. Rippers, commonly known as a sub-soilers, can be used to operate deeper than Maresha by up to 5- 10 cm.

CF resulted in improved tef and maize yields in Ethiopia. Ripping + ridging + fertilizer yielded improved maize grain yields with 40% over conventional practice (using Maresha and no fertilizer). Also CF practices using rippers with wing-ploughs and fertilizer resulted in significantly higher tef yield than conventional practices. Combined conservation agricultural practices (ridging, sub-soiling or reduced tillage with maresha and wing plough) with fertilizer resulted in almost doubled tef grain yield compared to conventional use of Maresha and no fertilizer. It was also indicated that conservation agricultural practices with no added fertilizer increased tef grain yields with 20–50% for ripping + wing plough and ripper + ridging as compared to conventional non-fertilized tillage using maresha. Nevertheless, CF is a rarely practiced method of crop production in Ethiopia.

The adoption of CF in Ethiopia would enable farmers to benefit from improved crop yields and other associated economic gains and also contribute to the sustainable management of land resources in the country. Besides, the policy environment in the country is favourable for promoting CF as the government has recently developed a national strategy for Sustainable Land Management practices in which the CF is an important component. Despite such a sound policy framework, the practical implementation of the CF on the ground has not yet materialized. The promotion of CF under this project is hoped to help shake-up the current impasse in taking the SLM policy into action and facilitate the conditions for greater involvement of the government in materializing its own policy in the long run. Therefore, the adoption of CF, which aims to conserve soil and water by using surface cover (mulch) to minimize runoff and erosion and improve the conditions for plant establishment and growth could minimize the impact of climate change and land degradation in Ethiopia.

Conservation farming is a rarely practiced method of crop production in Ethiopia. As a result of the project intervention, farmers will learn how to improve the productivity of their land through the application of CF. Thus, due to the adoption of the CF, the soil fertility will improve, soil erosion is reduced, soil structure degradation is minimized, productivity of rainwater is improved and ultimately the productivity of the land is improved and results in more grain production; food security is achieved and the environment is sustainably managed.

Major Objective:
Improved food and nutritional security in the dry lands and mitigation of the effects of climate change through the adoption of sustainable soil and water management methods that enhance productivity of dry land soils by improving soil physical structure and fertility, increasing water productivity, and promoting rapid germination and optimum plant population.

Sub-objectives:
1. improve the productivity of dryland soils using sustainable soil fertility management methods that enhance soil fertility, availability of plant nutrients, and nutrient use efficiency (inclusion of legumes in the farming system, application of organic fertilizers, using fertilizer application methods that improve its availability to the plants, and soil mulching)

2. improve soil structure and rainwater productivity to create favourable conditions for crop growth through minimized soil disturbance and soil mulching

3. Improve human nutrition through the inclusion of legumes in the farming system

4. minimize risk of crop failure through maintaining optimum plant density and promoting rapid germination of seeds

5. improve the safe use and application of fertilizers and seeds by using suitable tools and methods

6. minimize dependence on oxen plough based crop production

7. dissemination and scaling up of best Practices of CF to similar areas in the country and

8. determine the contribution of CF in GHG emission reduction

Tested Techniques

The combination of the CF treatments tested include: soil preparation methods (e.g ripping and wing ploughing), moisture conservation methods (e.g. tied-ridging and basin pits), and both the application and non-application of site adjusted fertilizer ( See Tables 1a-d for a full overview of the tested techniques). The tested treatments varied across the sites depending on the farming systems of the respective areas. In the Mehoni/Alamata area of Tigray, moisture is the most critical limiting factor, thus the CF treatments selected for testing centered on moisture conservation e.g. tie-ridging and basin planting. In Loca Abaya in SNNPR, where moisture conservation is also an issue, tie-ridging for moisture conservation was also tested in addition to other treatments. In the Tach Armachiho area of Amhara, where the soil is characterized predominantly by black vertisols, the selected treatments centered mainly on reducing the effect of water logging and striga infestation.

Table 1a. Sets of treatment combinations tested using maize in Borecha/Loca Abaya (SNNPR)


Set1A

Set B

1

Conventional2 with no fertilizer

Ripping + Fertilizer

2

Conventional + Fertilizer

Ripping + Tied ridging + Fertilizer

3

Ripping3 + Fertilizer

Conventional + Fertilizer

4

Ripping + Tied ridging + Fertilizer


5

Ripping + Tied ridging + haricot bean inter-

cropping


6

Ripping + Tied ridging + haricot bean intercropping +Fertilizer



Table 1b. Sets of treatment combinations tested using sorghum in Tach Armachiho (Amhara region)


Set A

Set B

1

Conventional with no fertilizer

Ripping + soy Bean Intercropping + Fertilizer

2

Conventional + Fertilizer

Ripping + Fertilizer

3

Ripping + Fertilizer

Conventional with no Fertilizer

4

Ripping + Soybean Intercropping


5

Ripping +soy Bean intercropping + Fertilizer



Table 1c. Sets of treatment combinations tested using finger millet in Tach Armachiho (Amhara region)


Set A1

Set B

1

Conventional with no fertilizer 2

Ripping+ Wing plow + Fertilizer

2

Conventional + Fertilizer

Ripping+ Fertilizer

3

Ripping3 + Fertilizer

Conventional with no Fertilizer

4

Ripping + Wing plow + Fertilizer


5

Ripping + soybean intercropping


6

Ripping+ soy beanintercropping + fertilizer



Table 1d. Sets of treatment combinations tested using Sorghum and Tef in Mehoni/Alamata(Tigray region)


Sorghum

Tef

Set A1

Set B

Set C

SetD


1

Conventional with no fertilizer 2

Basin +

Fertilizer

Transplanted on

Basin + Fertilizer

Ripping + Tied Ridging + Intercropping + Fertilizer

Conventional with no

fertilizer

2

Conventional +

Fertilizer

Conventional + Fertilizer

Transplanted with Ripping + Tied Ridging + Fertilizer

Ripping + Tied Ridging + Fertilizer

Conventional +

Fertilizer

3

Ripping3 + Tied Ridging + Fertilizer


Conventional +

Fertilizer

Conventional +

Fertilizer

Ripping + Tied Ridging + Fertilizer

4

Ripping + Sub-Soiling + Fertilizer




Ripping + Wing plow + Fertilizer

5

Ripping + Tied Ridging + Green Gram

Intercropping





6

Ripping + Tied Ridging + Green Gram Inter-

cropping + Fertilizer





NB.

1: set refers to a group of treatments planted on an individual farmer's plot

2: Conventional refers to repeated (3 or more times) plowing using a traditional plow (maresha)

3: ripping refers to opening a planting line using a ripper


The results from the study have not yet been finalized, however, a review of the data collected in 2012 and 2013, along with an initial review of the data from 2014, point to clear benefits for adopting certain CF treatments. Some of the most impressive results reveal: Enhanced utilization of rain water in areas receiving low and erratic rain fall; significantly improved grain and biomass yields; improved drainage in water-logged soils; reduced levels of striga infestation; improved drainage in water-logged soils; reduced levels of soil disturbance and erosion; reduced dependency on oxen for land preparation; and reduced input and labour costs. The complete set of results will be available in a full report set to be published in Fall 2015.