Intercropping wood with grains

Many scientists, technicians, politicians, those responsible for financing agencies and opinion leaders believe that the only solution to feed the growing world population is intensive agriculture that uses industrial inputs, mechanization and biotechnological resources.

This model, when put into practice in regions and territories where educational and savings levels are low, the strength of local culture is intense and the possibilities of contact and use of biotechnological innovations are reduced, instead of bringing the expected benefits, it has caused significant losses of forests and soil, due to felling and burning and intensive mechanization, which causes erosion, desertification, salinization and other processes of environmental degradation.

In Brazil, this situation was worsened by the problems caused by mineral and vegetable extraction and the construction of hydroelectric plants. In a way, this worsening also occurred due to the lack of recognition of the influence of family farming on Brazilian agricultural production.

The senseless devastation of natural forests for the most diverse uses, in some Brazilian regions, has reduced the supply of wood to the point that it no longer meets the demand in these regions. Furthermore, it has accentuated droughts, intensified erosion and increased the silting of water courses and the occurrence of floods.

In many Brazilian states there has been a shortage of wood, both for energy and for sawmills. There are also numerous areas with the potential for agricultural use diminished by poor use, many of them in a state of degradation. Due to this situation, environmental protection has been one of the most debated topics in discussions aimed at establishing a standard of agricultural development for this millennium.

Due to the current search for new agricultural standards, the forestry component has acquired substantial importance. The efforts made to implement reforestation and forestry programs with a view to sustainable development of the agricultural and forestry sectors and their main actors, rural producers, have been great. However, it has been very difficult for agricultural science professionals to prove that the benefits of forests and trees are of immediate importance to those who live in or around them. For this reason, forestry activities have been forced to occupy increasingly marginal sites.

One of the main obstacles has been the fact that most producers discard the planting of trees on their properties, as they take away areas destined for agriculture or livestock. Because of this, agroforestry, and within it agroforestry systems (SAFs), could be of great importance. SAFs, which are management systems that increase the sustainable yield of land by simultaneously and deliberately combining the production of woody species with agricultural or pastoral activities on the same unit of land, considering the experience and needs of the local population and the market , present several advantages compared to monocultural systems. Among them, the most efficient use of space, the effective reduction of erosion, the sustainability of production and the stimulation of the production economy, on a participatory basis, stand out.

Agroforestry projects, on lands currently occupied by monoculture systems, could be a good option for the simultaneous supply of wood, food and other goods. They will be able to benefit forestry entrepreneurs, reducing the implementation and initial maintenance costs of their stands, with the income produced by intercropping, as well as farmers, ensuring more favorable environmental conditions for their crops and a supply of wood for their own use or for business. Furthermore, the planting of trees in crops constitutes a form of replacement, albeit small, of the forest cover destroyed during the advance of the agricultural frontier.

An economic evaluation of the use of agroforestry systems (SAFs) in the eucalyptus planting program in the Northern Pioneer of the State of Paraná showed highly favorable results.

Like forestry plantations, SAFs result in another advantage, which is that they are much more resistant to some climate problems. Producers in the southern states of Brazil with agroforestry properties who planted short-cycle crops and also yerba mate and/or forest species associated with short-cycle agricultural crops, from an economic point of view, suffered much less from the problems of the last drought. Furthermore, the forestry component can function as a green savings account.

Based on this knowledge, it can be said that agroforestry systems constitute an interesting alternative for implementation in the region, although knowledge about their current and potential use is scarce. This scarcity of information has hampered its dissemination throughout rural extension and existing cooperatives.

Research institutions, therefore, have an excellent opportunity to contribute to improving the environmental standard of Brazilian agriculture, organizing and disseminating knowledge about technologies (species of multiple use for plantations as components of SAFs, for example), practices (planting in alley, windbreaks, among others) and silviagricultural agroforestry systems (trees and/or shrubs with agricultural crops).

Moacir José Sales Medrado

Agricultural engineer, PhD in Agronomy, Specialist in Agricultural Planning and Agroecosystem Management, and former researcher at Embrapa Florestas

Vanderley Porfírio-da-Silva

Agricultural engineer, Master in Agroecosystems, Researcher in Silvopastoral Systems at Embrapa Florestas