Advantages of agroforestry systems
Advantages of agroforestry systems
As is known, agroforestry essentially consists of integrating tree cultivation into agricultural environments. It is a practical and low-cost means of implementing many forms of sustainable management of natural resources.
Growing research on agroforestry systems, applied and conducted in various parts of the world, highlights that these determine a series of environmental advantages that can be summarized with the following table:
1. they have an overall productivity higher than the sum of equivalent monocultures;
2. they diversify agricultural production;
3. they reconcile food production with biomass production;
4. they reduce the input of fertilizers, plant protection products, etc.;
5. they increase biodiversity, directly and indirectly;
6. they improve soil fertility;
7. they protect the soil from erosion and pollution;
8. they improve water quality;
9. they increase the carbon stored in the system;
10. they improve the landscape.
Agroforestry systems are therefore considered advantageous from both an environmental and productive point of view for several reasons.
We have said that trees in agroforestry systems absorb CO2 from the atmosphere during photosynthesis and store carbon in their tissues. The average carbon storage through agroforestry practices has been estimated at: 9, 21, 50 and 63 Mg C Ha−1, in semiarid, subhumid, humid and temperate regions, respectively. For small-scale agroforestry systems in the tropics, potential C sequestration rates range from 1.5 to 3.5 Mg C Ha−1 year−1 (Montagnini F., Nair P.K.R. 2004).
The presence of trees in agroforestry systems improves the prevention of soil erosion. Tree roots help stabilize the soil, minimizing the risk of erosion caused by wind and water. In addition, fallen leaves and other plant debris help increase soil organic matter, improving soil structure and fertility.
Agroforestry systems provide habitat for a wide range of plants, animals and soil organisms. The variety of species present in agroforestry systems supports local biodiversity, providing shelter, food and habitat for many species, including beneficial insects, birds and small mammals. This biodiversity also contributes to the natural control of pests and diseases.
The use of trees in combination with agricultural crops reduces the need for chemical plant protection products and fertilizers. For example, trees provide shade for underlying crops, thus reducing competition with weeds and the need for herbicides. In addition, some tree species fix atmospheric nitrogen, reducing dependence on nitrogen fertilizers.
The presence of trees in agroforestry systems helps improve water management. Trees help reduce evaporation of soil water, maintaining a more humid environment for underlying crops. Furthermore, agroforestry systems significantly reduce the risk of flooding and improve water quality through natural filtration.
Many scientific studies have underlined not only the validity of these systems, which contrast with monocultures, often herbaceous, but the need for their introduction and integration into agricultural landscapes (Plieninger T. et al. 2020).
In fact, we know how the structures and functions of terrestrial ecosystems have strong effects on global biogeochemical cycles.
We have observed that research of merit has highlighted the need to design and prepare agroforestry systems that, in addition to taking into account intrinsic ecological elements of the landscape and their socio-economic factors, can have positive effects on the microclimate, attenuating environmental stresses linked to monoculture systems. The agroforestry models tested were also designed on the basis of a geographical analysis of land use.
Agroforestry systems have a positive effect on the water and carbon cycle, in terms of ecosystem flows of transpiration and assimilation, improving the use of water resources and the productivity of herbaceous crops.
In addition to the economic implications, which will be addressed in the next chapter, this research has been able to verify that the elements of innovation, introduced in the context of the development of agroforestry activities, can be concretely used by territorial actors.
It is clear that in the territories that are the subject of some studies, such as, for example, the one carried out for the Val d’Aniene (Alimonti M. 2010) it can be stated that the territories in question, although presenting significant socio-economic problems, show an availability of environmental resources such as to allow a recovery of the functionality of the ecological landscape and its constituent elements and a better integration between the social and ecological components.
It is useful to specify, therefore, that agroforestry systems often do not replace common agricultural practices, but integrate and improve them in order to produce more and in a more sustainable way.
In conclusion, the development of agroforestry systems will contribute to recreating a fair balance between agricultural activities and the environment, to safeguard the agricultural traditions of the various territories and to provide a possible reorganization of the same, without compromising the income of farmers; also contributing to an increase in the products and services offered.
Guido Bissanti