Background/rationale
Tea is the major product exported by Kenya. Tea plants require large amounts of macro and micronutrients. In the absence of these nutrients, the yield and quality of tea are reduced. Kenya's tea industry currently depends predominantly on imported inorganic fertilisers. Studies have shown that using inorganic fertilisers is unsustainable in terms of their prohibitive cost, and the need to improve tea production and restore soil fertility. Thus, there is a need for sustainable interventions that will restore the soil's physical and chemical properties leading to optimal tea production.
Therefore, there is a need to look for an alternative source of plant nutrition, such as organic fertilisers that are safe, affordable, and readily available. Organic fertilisers help replenish lost organic matter in the soil, supplement the existing soil nutrients, and minimise environmental pollution associated with inorganic fertilisers. Another option is organo-mineral fertilisers (OMFs) which combine organic amendments with reduced amounts of mineral fertilisers, potentially offering a balanced and sustainable approach. This recycling of organic waste promotes a circular economy and provides a sustainable source of nutrients that will both feed the crops and act as a tool for the re-introduction of organic matter into agricultural soils. Given the benefits of organic and OMF, their use in tea production should provide a sustainable and cheap source of fertilisation. This will help to reduce over reliance on imported inorganic fertilisers, which raises production costs and poses environmental and health effects. Different locally available feedstocks can be utilised in making OMF, thus making these fertilisers cheap and readily available for tea production.
The research question that needs be answered are centred around how efficacious the OMF for tea is and establishing whether it can be a greener option for the crop and the planet.
Project aims
The overall aim of the project is to achieve climate-positive tea agronomy through the evaluation of organo-mineral fertilisers, through the following objectives:
- To optimise composting and develop vermicomposting processes for the efficient valorisation of locally sourced feedstocks into high-quality organic fertilisers;
- To optimise and characterise organo-mineral fertiliser formulations for their chemical and physical attributes;
- To evaluate the efficacy of organo-mineral fertilisers in enhancing beneficial soil microbial communities;
- To assess nutrient mineralisation patterns of OMF between successive applications;
- To determine the impact of OMF on GHG emissions and the soil microbial communities;
- To determine the impact of OMF on diffuse pollution through erosion studies.
Benefits
Potential benefits from the project include:
- Improving soil health through use of OMF;
- Reducing the carbon footprint of fertiliser used in tea by relying on OMF;
- Minimising run-off of nutrients into water bodies in target catchments by recovering nutrients from wastes;
- Increased farm productivity, which could lead to better nutrition for urban poor;
- Increased productivity meaning greater profit, improved livelihood and economic growth;
- Creating jobs in local economies.
