What is agroforestry?
Put simply, agroforestry is the integration of trees and shrubs in a farming system. It includes hedgerows, wood pasture, contour planting and parkland. It mimics the processes happening in a forest with different structures of trees playing roles that all benefit each other.
Worldwide there are 1 billion hectares and are responsible for sequestering 0.73 gigatons of CO2 from the atmosphere in the last 10 years. Predominantly agroforestry occurs in tropical and sub-tropical areas. Indigenous people have been practicing this for years in forests as it is a natural way to maintain biodiversity in the forests whilst simultaneously providing food. The common combination is coffee and chocolate!
What are the main benefits?
- It enhances farm productivity. A study in 2014 found that incorporating trees like acacia increases the productivity of degraded land, resulting in an increase in crop yield of between 89 and 318%
- Increase in wildlife as more trees and hedges provide wildlife habitats of all kinds with providing shade and shelter. This also means there are more pollinators which in turn help the crops. It also boosts livestock welfare.
- Soil health is improved as there is a greater diversity above and below. This optimizes soil as a habitat for a wealth of different organisms that help soil structure and processes within it. The soil erosion rates are lower and tree roots gather nutrients and water from deep in the soil which benefits both crops.
- Agroforestry contributes to climate change mitigation There is enhanced carbon sequestration. When planting at a density of 50-100 trees/ha, carbon sequestration is 1-4 tonnes of carbon per year per hectare. For context, the average person in the UK is responsible for 5.5 tonnes of carbon dioxide emissions a year.
- There are year-round benefits as the different crops cover the whole of the seasonal period; arable crops primarily use water, nutrients and sunlight in spring and early summer. The trees need these resources right through to late autumn, enabling more energy to be captured from sunlight and turned into food. Different crops provide harvest all year round so farmers can sell on the market and increase income. This is especially useful for farmers relying solely on agriculture as a means of income and who are cut off from the areas where modern agriculture fails to provide food security.
- Water management is better in agroforestry systems as water quality is protected from pollutants and this helps slow the flow by improving infiltration of water into the soil. Eastern Zambia and Zimbabwe, steady-state infiltration rates were 42 to 600% higher when maize was rotated with leguminous trees compared to monocultures of maize. Time to water runoff was also longer by 40 to 133%, and drainage was improved by 88 to 900%. The land has better water carrying capacity.
Examples:
Canada – https://www.agr.gc.ca/eng/agriculture-and-the-environment/agricultural-practices/agroforestry/?id=1177431400694 page to provide tips and advice on what to do and links on where to find more information.
https://www2.gov.bc.ca/gov/content/industry/agriculture-seafood/agricultural-land-and-environment/agroforestry/agroforestry-resources#:~:text=Canada&text=Agroforestry%20is%20the%20integration%20of,essential%20part%20of%20the%20farm.&text=The%20current%20and%20future%20economic,animal%20and%20plant%20resource%20base. Same as before – with a focus on British Columbia as well.
Trees.org – their mission is to end hunger whilst alleviating poverty for farmers by teaching regenerative agriculture practices.
- They have an education focus: their 4-year programme to help farmers in poorer areas learn better ways to farm and to look after their land. The separate stages of the programme involve stabilization of the soil, diversification of plants, optimization of practices and conservation, and implementing a strategy for the long term.
- Regenerative agriculture allows for an increase in nutrition, economy (sales of a greater diversity), selling honey and homemade pesticides. Increases access to education, empowerment of women. Decrease of migration as work opportunities increase.
- Returns on investments are higher than the initial start-up costs.
- 8/9 months to have up to 12 different crops on a farm
- Trees aren’t the only solution
- There are conflicts with the Government. There is a greater financial incentive to grow monoculture.
Improvements for the future
There have been low levels of agroforestry in the past. Historically farming and forestry have been seen as separate entities with little transfer of skills, processes and knowledge between them failed to recognize landscape-scale benefits of tree and agricultural integration. Government bodies do not provide grants to support agroforestry in many parts of the world. Adequate training and extension services are needed to improve the management skills of agroforestry farmers. Tree management and maximizing the beneficial interactions between trees and crops can often require more skills than open-field agriculture.
Overall, agroforestry is important for all avenues of helping the environment. By applying agroforestry we can rehabilitate 35% of global agricultural land that is degraded and this is crucial if we want to help prevent agriculture’s contribution to climate change.