The performance of the agriculture sector, which experienced a growth of 4 per cent, in the last few years should cause a shudder to stakeholders at a time when the country is all songs for the green revolution.
Agroforestry can supplement use of fertilisers.
Any measure directed towards revamping agriculture must take cognizance of the underlying causes. The small agricultural growth statistic has been attributed to various factors, including drought in 2006 and the financial crunch since 2008.
However, interactions with farmers around the lake zone areas of Shinyanga, Muleba and Mara also reveal a measurable lack of access to inputs in some areas and declining soil fertility in others.
While the ministry of Agriculture, cooperatives and Food Security has been working towards addressing the gap in access to inputs through offering fertiliser and subsidies, challenges still abound. Though the impact of these subsidies has not yet been quantified, it is apparent that the results are not yet optimal.
To counter problems of reliance on fertilisers as input, arguments with research findings have confirmed that Agroforesty can quickly and cheaply reduce food and water insecurity. This is an integrated approach of using the interactive benefits from combining trees with crops and/or livestock.
It combines agricultural and forestry technologies to create more diverse, productive, profitable, healthy and sustainable land-use systems. According to the World Agro forestry Centre, agro forestry is a collective name for land use systems and practices in which woody perennials are deliberately integrated with crops and/or animals on the same land management unit.
Agroforestry systems can be advantageous over conventional agricultural and forest production methods through increased productivity, economic benefits, social outcomes and the ecological goods and services provided. It also has the potential to help reduce climate change since trees take up and store carbon at a faster rate than crops.
The Director General of the World Agroforestry Centre (Icraf) Dennis Garrity says agroforestry, including rotational fallows, intercropping and biomass transfers improve soil quality leading to higher crop yields. A study by Icraf scientists on fertiliser trees that capture nitrogen from the air and transfer it to the soil found that agroforesty reduces the need for commercial nitrogen fertilisers by up to 75 per cent while doubling or tripling crop yields.
On the rural sides of Shinyanga and areas around the Lake Victoria basin, it is evident that as years go by, farmers are in more need of more fertilisers. However, recent research is suggesting more use of agroforestry to keep crop land more productive in the face of current fears for food security the world over. Conservation of forests and other natural resources will feature highly at the 2nd World Congress of Agroforestry in Nairobi from August 23-28.
Icraf is cooperating with national agricultural research systems in Southern and Eastern Africa to develop agroforestry. Garrity says that research and development have been going on for many years but there has been very little access by farmers, noting that the practice of growing trees on farms is one component of agroforestry with many benefits like replenishing depleted soil fertility.
According to Garrity, trees like faidherbia, gliridcida and sebsania, when planted with crops suppress weeds while increasing organic matter in the soil. Agroforestry, he explained, is not based on single specie and appropriate trees must be adapted for different geographical locations. The practice improves the soil structure so that it holds more water. It is evident that large chunks of land still have a thirst for fertilisers.
Even as the government has a programme for fertilizer distribution, it still has a long way in covering an entire country whose economy largely depends on agriculture. Agro forestry is a low-cost, risk reducing and productivity-enhancing technology that smallholder farmers can adopt and adapt, especially in wake of climate change.
It is viewed as a win-win technology which serves the dual purposes of agricultural intensification and environmental improvement or natural resources conservation. However, agro foresters and environmental advocates sometimes experience great difficulty convincing their agriculturist colleagues that agroforestry (AF) makes agronomic, economic and environmental sense and is a worthy investment.
In the absence of hard data to support their cause, advocates can use anecdotes and true stories to back successful initiatives. At Bunda in Mara, farmers are using a traditional agricultural practice where villagers farm undeneath the canopy of the white-thorn acacia tree.
They reported having personally compared crop growth below the F. albida trees and further away from the tree. They observed that crops under the tree produced better yields “as if they had fertilizer applied to them.” It was also suggested that the soils under the trees may have become fertile because cattle came to feed on the pods and sleep below the tree and in doing so deposited manure which improved soil fertility below the trees.
Local and international policies need to be refined to incorporate agroforestry components to increased productivity, environmental conservation and sustainability of programmes. This is proposed in a paper titles “New climate, new agriculture: How agroforestry contributes to meeting the challenges of agricultural development in Tanzania’ by Aichi Kitalyi, World Agroforestry Centre Representative in the country.
The paper which highlights how the use of agroforestry “fertilizer trees” can compliment the fertiliser subsidy programme by the Government of Tanzania is co-authored by Gerson Nyadzi, Mary Lutkamu, Remen Swai and Benjamin Gama. Since December 2009, the government, through the Kilimo Kwanza, initiative aims to increase the agricultural productivity.
Among other goals of Kilimo Kwanza initiative is to transform peasant and small farmers to commercial farmers through emphasis on productivity and tradability. This would involve an increase in inputs in terms of mechanisation and use fertilizers to increase productivity.
Speaking in reference to the Kilimo Kwanza initiative, Aichi says that as useful as it is, a fertilizer subsidy without complimentary use of agroforestry options can neither reverse the depletion of nutrients in the soils not provide optimal nutrients for a Green revolution.
According to Aichi, the fiscal costs of fertilizer subsidies limit use of recommended levels of fertilizer. She also mentions lack o enough fertilisers of fertilizer and Poor infrastructure that reduces the efficiency of distribution as other limitations of inorganic fertiliser. According to the article, inclusion of Agroforestry in the Kilimo Kwanza initiative would help increase sustainability as well as productivity in farms.
“Agroforestry would bring in the added benefit of organic fertilizer, environmental conservation and sustainability of the programme,” she says. Evergreen Agriculture, Combining conservation agriculture with trees on farms, is gaining momentum across Africa as a solution to declining soil fertility and low crop yields while helping to combat climate change.
In Tanzania, the Faidherbia – Maize farming system in Southern Highlands, is a good example where farmers obtain high yields without use of inorganic fertiliser. She proposes that for smallholder farmers use of conservation agriculture with trees will address the gap identified in the Kilimo kwanza. It also targets to improve crop yields with minimal financial and technological requirements.
By ORTON KIISHWEKO, Tanzania Daily News
