Trees in the farm: carbon sequestration in agroforestry
Farming leverages the land’s potential to produce crops for people’s needs. So it may not come as a surprise that integrating varieties of not just plants, but also of trees or shrubs, can shape productive farms over time.
This is agroforestry. It is an approach to land management that has trees and shrubs thriving alongside crops and livestock within one system. Agroforestry is known to expand the functions and benefits of farmlands for farmers and nature. But despite being one of the most traditional land management strategies, there are still many barriers to reaching its full potential for modern farms.
Discover what agroforestry is, its types, its many benefits, the potentials for carbon sequestration in agroforestry, and what you need to consider to get started.
What is agroforestry?
Simply, agroforestry is agriculture with trees. In a traditional farming landscape, whether crops or livestock (or both), trees or shrubs are incorporated purposefully to make up an agroforestry system.
Traditional societies have been known to use the land this way to yield abundant varieties of harvests both from crops and trees. In recent times, agroforestry is seen as a more sustainable approach to managing lands by balancing an ecosystem where trees, plants, and animals exist side-by-side co-beneficially within an area, similar to what can be observed in natural landscapes.
While there is a general distinction between forests and farmlands, agroforestry makes use of both elements in a production system where trees are arranged between crops or around the farm’s perimeter, depending on how the agroforestry system is designed.
What are the types of agroforestry?
There are many examples of agroforestry that accommodate particular needs and requirements of each land manager. In Europe, there are five distinct types of agroforestry systems, where the forestry elements of the farm are arranged a certain way for specific goals and purposes.
- Silvoarable agroforestry: the trees and crops are integrated into an agricultural land
- Silvopastoral agroforestry: the integration of trees within a grazing system for livestock
- Hedgerows, shelterbelts, and riparian buffer strips: Trees or shrubs are planted around agricultural land to form a protective barrier or to mark territory. Riparian buffer strips mean planting trees or shrubs around nearby bodies of water like ponds, ditches, or streams.
- Forest farming: crop cultivation within a forest landscape
- Homegardens: combinations of trees and food production close to homes.
The first three types are common among cropland farmers. And even more comprehensively, an agroforestry system can also be designed where crops, livestock, and trees are incorporated. This type is known as agrosilvopastoral agroforestry.
What are the benefits of agroforestry?
With careful planning and design, farmers can reap an array of benefits related to soil and environment, income and productivity, as well as climate change adaptation and mitigation.
Different plants and trees have different requirements. And in any given area where resources are shared, agroforestry systems can promote mutually beneficial effects to different life living off the land — while farmers gain new income streams.
Here are five reasons why your farm can benefit from agroforestry.
Biodiversity
Introducing complementary plant and tree species help make the best use of resources in a farm. Some crops perform better with the right amount of sun exposure which can be regulated with the shade provided by trees. Similarly, trees can serve as windbreaks that protect crops from winds that damage plants. The same trees also act as shelter for small animals like birds and insects that can provide a wider ecosystem value to the environment.
There are many incidences where mono-cropping increases the incidence of pests and diseases spread on a farm. By introducing another vegetation type, pests and diseases, and therefore, the use of pesticides and other chemicals can be minimised.
Soil health
Well-planned agroforestry plots can appropriately provide for the varying requirements of crops and trees without harmful competition between species. For example, deeper rooting perennial trees can make use of nutrients and water below where crops take root. Each interacts with the soil depth according to their growth requirements.
The presence of roots in different soil levels can also improve water retention, decrease soil erosion, and overall improve soil fertility by trapping nutrient-building soil organic matter.
Productivity
One thing to remember about agroforestry systems is that crops and trees are planted so that they can benefit each other in consideration of a farm’s unique condition. Take, for example, leguminous trees can help fix nitrogen in the soil which is beneficial for the plants.
Building soil health enriches the land over time and trees regulate the productivity of lands by cycling nutrients and resources sustainably.
And instead of producing a single crop on a farm, trees can be planted to produce other varieties of food. Apart from food production, trees can be planted for fuel (firewood), fodder, fibre, and medicine. Now a farm produces a variety of raw products with multiple uses.
Resilience
A good mix of trees and plants in a landscape helps maintain soil stability that can better withstand extreme weather events and climate change that puts an entire farming operation at risk. With the incidence of droughts and heavy rainfall getting more frequent and intense, a highly resilient farm will be better prepared for many climate uncertainties ahead. Similarly, carbon sequestration in agroforestry maximises the capacity of landscapes to store and maintain carbon for the long term.
Diversified income
Growing trees that bear fruits or nuts are wonderful additions to introduce new income streams beyond the main crop of the farm. Other parts of certain trees can be harvested for the production of other resources used for making medicine, fodder, or other raw materials.
The environmental benefits of trees in cropland can see the reduction of chemical inputs, reducing operational costs.
Carbon programs in farming can also reward farmers with revenue when there is a measured increase in carbon stocks in the field stored in the soil and tree biomass.
→ Consult our expert agronomists to know how you can leverage agroforestry in carbon farming.
A great potential for carbon sequestration in agroforestry
Agroforestry is a carbon farming strategy to help control the amount of greenhouse gas that accumulates in the atmosphere. Croplands can store carbon in the soil but some CO2 goes back into the atmosphere when plants are cultivated and harvested each season. Trees on the other hand store carbon in the trunks and roots (biomass). Tree biomass are reservoirs of carbon that can limit the amount of emissions cropland cultivation emits.
The potential to sequester carbon in agricultural lands can increase when trees are also present in the field. One study estimates that the potential for carbon sequestration in agroforestry from arable lands in Europe can go up to 7.29 t C ha−1 a−1. Maximising the carbon farming potential of agroforestry can reward farmers with genuine carbon credits sold to organisations looking to offset their emissions.
Is agroforestry right for your farm?
Creating a successful agroforestry landscape takes knowledge of plants and trees, and a good understanding of your farm conditions. Prior planning and proper implementation are crucial to make the most of your land. And because trees grow at a different pace than crops, payoffs can also take longer.
However, a sustainable land management system like agroforestry is designed with longevity in mind. Its benefits for the environment, productivity, and income are designed to accumulate over time.
Engaging in carbon programs that reward farmers for successful carbon sequestration in agroforestry should be considered early to help make the most of an agroforestry landscape.
Curious how you can earn income from carbon sequestration in your farm?
Sources
- Burgess, P., Newman, S., Pagella, T., Smith, J., Westway, S., Briggs, S., Knight, I., Whistance, L. (2019). The Agroforestry Handbook. Agroforestry for the UK. 1st Edition (July 2019). Soil Association Limited, https://www.soilassociation.org/media/19141/the-agroforestry-handbook.pdf
- Kay, S., Rega, C., Moreno, G., den Herder, M., Palma, J., Borek, R., Crous-Duran, J., Freese, D., Giannitsopoulos, M., Graves, A., Jäger, M., Lamersdorf, N., Memedemin, D., Mosquera-Losada, R., Pantera, A., Paracchini, M.L., Paris, P., Roces-Díaz, J., Rolo, V., Rosati, A., Sandor, M., Smith, J., Szerencsits, E., Varga, A., Viaud, V., Wawer, R., Burgess, P., Herzog, F. Agroforestry creates carbon sinks whilst enhancing the environment in agricultural landscapes in Europe, Land Use Policy, Volume 83, 2019, pp 581-593, ISSN 0264-8377, https://doi.org/10.1016/j.landusepol.2019.02.025
- Aertsens, J., De Nocker, L., Gobin, A. Valuing the carbon sequestration potential for European agriculture, Land Use Policy, Volume 31, 2013, pp. 584-594, ISSN 0264-8377, https://doi.org/10.1016/j.landusepol.2012.09.003
- Bertsch-Hoermann, B., Egger, C., Gaube, V. et al. (2021). Agroforestry trade-offs between biomass provision and aboveground carbon sequestration in the alpine Eisenwurzen region, Austria. Reg Environ Change 21, 77. https://doi.org/10.1007/s10113-021-01794-y
