Dominic Kwadwo Anning

Kumasi, Ghana

An Overview Of Our Solution

Ghana has been predicted to face water shortage by the year 2025. Moreover, there is a spiral increase in prices of inorganic fertilizer in the country and consequently, farmers cannot apply the recommended dose for higher yields. Also, the burning or incorporation of fresh crop residues into the soil during land preparation adversely affect the environment. To address these problems, experiments were conducted to assess the effect of integrated compost and inorganic fertilizer application, and alternate wetting and drying (AWD) irrigation management on rice yield and soil health. Results from the studies revealed grain yield increase of 500 kg/ha, soil properties improvement over time, 40% of water used for irrigation saved and cost of production reduced by 27% when compared to the farmers’ conventional practice.

Who is this solution impacting?

Community Type

Rural

Organization type

individual

Ecosystem (select all that apply)

Grasslands

Population impacted

640 people

Size of agricultural area

50 hectares

Production quantity

4900 kg/ha

People employed

15 people

Describe your solution

Rice straw together with other crop residues that were burnt or incorporated into the soil during land preparation, which leads to air pollution and emission of methane gas, were composited before incorporation into the soil as basal application. Urea fertilizer was used as top dress application. The field was not continuously submerged but it was only submerged when soil moisture level dropped to 15 cm deep (AWD irrigation management). The solution increased grain yield and reduced the dose of inorganic fertilizer by half, consequently reducing the cost of rice production in the resource-poor rice producing communities of Ghana. Also, it improved the soil fertility over time through the gradual release of nutrients from the compost to crops and consequently reduced nutrients loss through leaching or run off. Moreover, it reduced water loss through percolation and seepage as well as increased water holding capacity of the soil due to the increased total number of soil pores. The solution saved 40% of water used for irrigation, providing a good solution to rice food security in water constrained environments. However, it recorded similar grain yield with the farmers’ practice. Water productivity was also increased since less water was used to produce more rice, thus increasing farmers’ income.

Describe your implementation

On-farm trial was conducted for farmers to assess the effect of integrated compost and inorganic fertilizer application, and alternate wetting and drying irrigation management on rice yield and soil health. Results from the trial proved that, AWD and integrated compost and inorganic fertilizer application were superior to the farmers’ practice (continuous submergence of the field and solely inorganic fertilizer application). The solution was easily adopted by the farmers due to its superiority and then implemented by training farmers on how to prepare compost using locally available materials (crop residues, ash as well as animal dung) and how to apply it. The matured compost was incorporated into the soil as a basal application while the inorganic fertilizer was applied as top dress. This practice helped the farmers to reduce the rate of inorganic fertilizer input and consequently reduced their cost of production. The gradual and slow supply of nutrients from the compost to the crops throughout the growing period together with the readily available nutrients from the inorganic fertilizer increased grain yield significantly by 8.2%. The emission of methane gas was reduced as a result of the non-continuous submergence of the field. The drying period during the AWD irrigation management allowed the soil pores to be filled with air which facilitated respiration and decomposition of the plant materials incorporated into the soil during land preparation. As a result of the non-continuous submergence of the field, 40% of the quantity of water used for the production was saved. Therefore, the amount of money used for irrigation was reduced. The only problem encountered in the solution was the preparation of the compost especially during the turning process which was quite laborious. Farmers were then advised to chop their feedstock into smaller pieces before composting them.

External connections

The Office of Research, Innovation and Development-University of Ghana (ORID-UG) funded both the pot and field experimentation. The labourers hired worked tirelessly during the experimentation. The irrigation rice farmers at Akuse and Kpong benefitted from the technology transfer. The concerted effort from all the stakeholders and financiers made the project a success.

What is the environmental or ecological challenge you are targeting with your solution?

Air pollution, production and emission of methane gas and water shortage. Generally, rice farmers in the country burn their crop residues after harvesting and threshing to ease in land preparation for the next cropping season. This practice pollutes the air and also causes nutrient mining as nutrient output exceeds nutrients input. Others also incorporate the fresh crop residues into the soil during land preparation (ploughing and puddling) which results in the production and emission of methane gas (120g of CH4/1kg of rice produced) especially under continuous submerged soil conditions. During submergence, all the soil pores are filled with water, and the crop residues that were incorporated cannot decompose which consequently leads to the production and emission of methane, a greenhouse gas which is identified to contribute to global warming and climate change. Submerging the field continuously also leads to high amount of water loss through evapotranspiration, percolation & seepage.

Describe the context in which you are operating

The continuous application of inorganic fertilizers has deteriorated soils and reduced crop yield. Also, there is 50% increase in inorganic fertilizer prices in the country due to the removal of government subsidy on fertilizer prices, high fuel prices and the fallen of the local currency on exchange market. Traditionally, rice is grown under continuous submerged soils which leads to high amount of water loss through evapotranspiration, seepage and percolation. However, Ghana has been predicted to face water shortage by the year 2025. Thus, rice production which is already low in the country will be negatively affected since rice consumes higher amount of water than any crop in the agricultural sector. To solve these problems, field and pot experiments were conducted to assess the effect of alternate wetting and drying (AWD) irrigation management and integrated compost and inorganic fertilizer application on rice yield and soil fertilizer.

How did you impact natural resource use and greenhouse gas emissions?

Burning of crop residues causes air pollution and nutrient mining since nutrient output exceeds nutrient input. Incorporation of fresh crop residues into the soil leads to the emission of methane gas which contributes to greenhouse effect and global warming. This practice also causes severe immobilization of nutrients especially under continuous submerged soil conditions. However, under this solution, crop residues were composted before they were incorporated into the soil to avoid air pollution and minimize the emission of methane gas. The poor soil condition at the site and at farmers’ fields have been improved over time through the practice of the combined compost and inorganic fertilizer management. The quantity of water used for irrigation has also been reduced through the practice of the alternate wetting and drying soil condition. Farmers’ income has increased due to the reduction in the cost of production through reduction in inorganic fertilizer purchases and less water used for irrigation.

Language(s)

Which language(s) are spoken in the area where your solution is implemented?

Water

40% of water used for irrigation was saved due to the non-continuous submergence of the field. The fields are only submerged when soil moisture level drops to 15 cm deep, that is, four days after disappearance of submerged water. This has reduced the amount of water loss through evaporation, seepage and percolation.

Food Security/Nutrition

The solution increased grain yield significantly by 8.2%. Thus, the adaptation of the solution increased rice production in the region. Moreover, the solution reduced the cost of production by 27% which led to expansion of farm sizes from an initial average of 7 acres to 10 acres. Rice production has subsequently increased from an initial amount of 4400 kg/ha to 4900 kg/ha.

Economic/Sustainable Development

The solution reduced the cost of production by 27%, thus increased farmers’ income. It also reduced half the amount of inorganic fertilizer input which has increased to about 50% in the country. The nutrient management also improved the soil health and fertility over time. Water loss was reduced since the field was not continuously submerged. The solution promotes sustainable rice production since less water is used to produce more rice and also improve the soil fertility and health.

Climate

There is production and emission of methane gas through the incorporation of fresh crop residues into the soil especially under continuous submerged soil conditions. This gas contributes to the greenhouse gases and consequently deplete the ozone layer. But the solution composts all the crop residues before they are incorporated into the soil and consequently limit the production and emission of methane gas which causes the greenhouse effect and warms the globe.

Sustainability

The solution improves soil fertility and soil health over time. Since the solution increase grain yield and reduce production cost, enough funds can be saved by farmers to increase their farm sizes. Moreover, the technology reduces the cost of production whilst grain yield increases. The technology also reduces the quantity of water used for irrigation, so in the era of water shortage, this technology will ensure the sustainability of rice production in Ghana.

Return on investment

The cost incurred in implementing the said activities was approximately 20,000 Ghana Cedis, whose equivalent in US Dollars is approximately 4,500. The amount was the cost of running the experiment and organizing training and workshops for rice farmers. In running the experiment, fields and labourers were acquired and hired respectively. Teaching and learning materials for demonstrations and presentations during the training were also acquired. The results corroborate the need to invest in rice production because the solution increased the profit margin by $100/ha.

How could we successfully replicate this solution elsewhere?

Firstly, farmers will be trained on how to prepare compost using locally available materials such as crop residues, ash, animal dung and top soil. Furthermore, farmers will be trained on how to incorporate the matured compost into the soil, apply the recommended rate of the inorganic fertilizer with respect to their farm size and when to apply them. In addition, farmers will be trained on how to prepare a ‘field tube’. The field tubes will be inserted into their fields to help them to determine the level of soil moisture. In the AWD irrigation management, the field is only submerged when the level of soil moisturedrops to 15 cm deep. With the above trainings, the solution can successfully be replicated. Materials needed for the training include: PVC plastic pipe, solder iron, ruler, shovels, rake, power tiller, polythene sheets, cutlass, inorganic fertilizers (NPK), wooden rule, etc.

Overview