Desertification is one of the most significant processes of environmental degradation and directly affects more than one billion people in the world, the vast majority of which are small farming families, traditional peoples and communities. At least half of the Brazilian semi-arid region (SAB) is already affected by desertification of varying degrees, 20% of which (181,000 km2) being in either an acute or very serious situation (MMA - UNDP, 2004). This figure is particularly worrying when we consider our semi-arid region to be the most populous of its kind on the planet: with 22.6 million inhabitants (12% of the Brazilian population), 38% of whom live in rural areas (IBGE, 2010). The over 1.5 million farming families living in the SAB represent more than 1/3 of the country's family farms. Although households with less than 10 hectares account for 60% (one million settlements) of the total area, they occupy only 6% of the land, showing a context of huge land concentration. In the SAB are also located 750 of the 1,000 municipalities with the lowest Human Development Index (HDI) and 2/3 of the country's rural poor (IBGE, 2000). There is no other environmental problem in Brazil that places such an area and such a contingent of people at risk.

The SAB is marked by the predominance of the caatinga biome (from the Tupi-guarani language, literally means ‘white stick’), the most vulnerable to desertification in the country due to the combination of its edaphoclimatic features, such as low rainfall levels, irregular precipitation, high solar radiation and shallow soils with low water retention capacity, and high susceptibility to erosion. The natural fragility of the biome has been further jeopardized by the impacts of anthropogenic pressures on ecosystems and, more recently, the effects of global climate change.

However, the magnitude that desertification has been assuming in the SAB, can, to an even greater extent, be attributed to the development model that has guided the occupation of the region, characterized by the historical concentration of wealth (land, water) and, more recently, by the imposition of the scientific paradigm of the “Green Revolution”. This combination, which combines archaic / conservative and "modernizing" structural elements, has been responsible for the profound alteration of the landscape and for the disruption of natural cycles that ensure the ongoing fertility of this ecosystem. Patterns of intensified production based on monocultures and agrochemicals have led to the exacerbated simplification of farming systems, hugely distancing the functioning of agroecosystems in relation to that of natural ecosystems. As a result, we are seeing accelerated rates of degradation of natural resources associated with unprecedented instances of social exclusion.

In the Brazilian semi-arid region, this pattern of conservative modernization is mainly visible on two fronts. On the one hand, we have the irrigated perimeters created through the construction of large public water works aimed at serving the demands of the agroexport sector (particularly fruit growing). In this instance, the combined use of intensive water and chemical inputs in an environment of shallow soils with high levels of potential evaporation (3,000 mm / year) has led to alarming processes of salinization, pollution and environmental degradation. According to data from the National Programme of Action to Combat Desertification and Mitigate the Effects of Drought (PAN-Brazil) in 2005, about 15% of the irrigated perimeter areas were already in advanced stages of salinization. On the other hand, in most of the region, modernization has been geared towards the expansion and intensification of livestock systems, with a strong emphasis on cattle farming. Ignoring the huge potential of the caatinga for fodder, this economic trend has been responsible for the widespread destruction of native vegetation to form pasture land¹. According to IBGE (2006), 43% of the area occupied for agricultural purposes is covered by pasture. Overgrazing caused by too many animals per pasture is a rule and exerts heavy pressure on natural resources. The unsustainability of this model is mainly evident during episodes of extreme drought, such as in the agricultural year 2012-2013, with the deaths of thousands of animals, especially cattle, and the reduction of semiarid livestock (sheep, goats and cattle) by more than 30%.

It should be noted that the majority of the population living in the rural areas of the SAB has not been contemplated by the development processes implemented in the region. With increasingly fragmented and diminished properties, due to hereditary mechanisms of sharing, generation after generation, these farming families have been led to intensify the use of the soil and the natural vegetation, without introducing adjustments in their technological base, which have continued to depend upon extensive landuse and environmental management approaches. Under these conditions, family production systems began to pressure natural resources beyond the limits of their ecological tolerance, inducing ecosystem degradation at levels incompatible with the generation of satisfactory incomes. Vicious circles have been established in which social impoverishment and environmental degradation are mutually reinforcing and aggravating, leading to situations of destitution and desertification.

Over the centuries, as a result of the rising population density, successive droughts in the semi-arid region, although characteristic of the regional climate, have given rise to an acute socio-environmental problem. As per Marengo et. Al. (2007): Global climate change announces to the semi-arid region an increase in climatic extremes and a worsening of its erratic character, increasing the vulnerability of production systems and further compromising its internal mechanisms that resist these fluctuations.

Addressing this trend, in which agriculture in the semi-arid region is both a cause and a victim of desertification processes, requires transformations in the existing approach to rural development in the region, which necessarily implies a reversal of the still dominant focus, exclusively centred around the pursuit of economic growth. Firstly, it is a question of construing a perspective aimed at promoting the natural potentialities of the caatinga biome, by developing methods of agricultural management that foster balance between the need for intensified land use and the regeneration capacity of the biophysical conditions that subsidize the fertility of agroecosystems.

In this sense, the unique characteristics of the caatinga, which include its vast biodiversity and great environmental heterogeneity, impose the need to generate unprecedented forms of land-use and productive management more adjusted to the ecological conditions of the Brazilian semiarid region. The bases for the development of such approaches lie largely in the widespread knowledge accumulated by the local communities throughout the history from their close coexistence with the limitations and potentialities of this environment / biome and in the experimentation of multiple variants of use and management of its resources. In this process of transformation and innovation, the active participation of the thousands of farming families living in the region cannot be dispensed with, rather the role of farmers of both sexes as managers of local knowledge and resources needs strengthening, in addition to the development of strategies aimed at activating local networks for encouraging innovation and the collective management of common goods (water and biodiversity). It is also imperative that this process be accompanied by profound reforms in the land and water structures so that peasant family farming can effectively constitute an economic and socio-cultural basis capable of promoting forms of productive management that are in keeping with the ecological specificities of the Brazilian semi-arid region.

Source: Revista Agriculturas | V. 9 - n. 3 | December 2012
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¹ The predatory nature of wood extraction practices for non-agricultural purposes (steel, pottery, bakeries, etc.) also plays an important role in the advancing deforestation of the native caatinga vegetation.