agroforestry is a collective name for “land-use systems and technologies where woody perennials (trees, shrubs, palms, bamboos, etc.) are deliberately used on the same land-management units as agricultural crops and / or animals, in some form of spatial arrangement or temporal sequence.”¹ Agroforestry is the third land-use method after agriculture and forestry and combines the technologies from the two other methods for more sustainable and productive land-use². Different variations of agroforestry systems are centered around problems they aim to address and include parks, shelterbelts and wind breaks, shade systems, crop-over-trees systems, alley cropping, strip cropping, fauna-based systems, boundary systems, taungyas, physical support systems, agroforests². Agroforestry may take place on private farmlands or in public areas, for example, along highways and roads or along rivers.
The practice of agroforestry goes back to ancient times. While particular practices of agroforestry differed from place to place, there are records indicating that some elements of the system go as far back as 4,500 years ago³. In some cases agroforestry manifested itself in trees on pasture lands, in others – as home gardens or covering ground crops³. Modern agroforestry finds its roots in development issues stemming from 1970s, particularly as a response to social and environmental downsides of high input agricultural practices on the poor populations. Many countries now have established policies supporting agroforestry practice and research³.
Advantages of agroforestry
Since then, most countries have recognized undeniable advantages of agroforestry, which are numerous. This land-use system places emphasis on interaction between different plants (crops and trees or bushes), which helps maintain soil fertility at satisfactory levels⁴. This generally helps produce better yields at reduced operational costs and create more drought resistant systems. Agroforestry is also recognized to help in reclamation of polluted soils, particularly salinized and acidified soils⁵.
Agroforestry helps minimize the need for chemical nutrients and fertilizers, which, among other positive effects, reduces the content of chemicals in agricultural runoff. On this point, trees and bushes play an important role in preventing soil erosion, which is an important factor in producing agricultural runoff in the first place. Reduced agricultural runoff means saved water and avoided pollution of drinking water in rivers and lakes.
Moreover, agroforestry systems offer a much better natural habitat to a variety of animals, birds, and insects than agricultural lands. Trees also serve as a protection to livestock from the sun and the wind in warmer months. Moreover, agroforestry systems are claimed to reduce the amount of agricultural insect pests and reduce associated diseases⁵.
On a more general level, agroforestry contributes to several globally relevant developmental issues. Thus, it has a positive effect on poverty reduction through increased production of wood for home consumption and sale². While wood may be used in the household for heating purposes, some studies also illustrated high energy savings from yard shelterbelts protecting houses from the wind and snow in cold months⁶.
In the recent decades, the role of agroforestry in climate change mitigation and adaptation received particularly strong attention. Trees are extremely useful in sequestering greenhouse gases⁶, and agroforestry is a way to combat deforestation that plagued the planet. According to some estimates, agriculture and deforestation contribute to as much as one third of global greenhouse gas emissions⁷. According to FAO, agroforestry addresses climate change through a number of solutions. It reduces or eliminates the need for deforestation because it provides wood products from the farmland. It also reduces the need to use soil nutrients and fertilizers by improving soil quality and maintaining good nutritional balance and fertility. Finally, agroforestry strengthens agricultural resilience by increasing crop yields and offering better environment for farm animals⁷.
Disadvantages of agroforestry
There are very few downsides to agroforestry. However, the main disadvantage for those trying to grow trees and shrubs for profit is time⁸. It is never a quick “fix” because trees, unlike crops, take a long time to grow and mature to really fulfill their purpose in the system. Finally, successful agroforestry systems require proper knowledge of technology (methods of combining different plants, their compatibility and effects on each other, etc.). Sometimes, agroforestry technologies may fail miserably when applied to the wrong situation⁸.