While food and nutrition security are issues that national and international organizations are tackling, one of the central problems often overlooked is the essential role of soils in providing nutritious food. Soils are the base for food production and food security. However, the majority of soils are in fair and poor conditions, with the most significant threats being erosion and loss of nutrients. In this study, we estimate the potential of soil loss, agricultural productivity loss, and nutrient loss for Brazil’s most important agricultural region, the Brazilian Cerrado, for the years 2000 and 2012. For this, we applied the Revised Universal Soil Loss Equation (RUSLE) model integrated with a geographical information system (GIS) to estimate annual soil loss rate and agricultural productivity loss, and used total nitrogen and total phosphorus in soil to estimate the annual nutrient loss rate caused by soil loss. All model factors and data were obtained from the literature. The results show that agricultural expansion in the Brazilian Cerrado is increasing the area of severe erosion, occasioning agricultural productivity decrease and soil nutrient depletion. The annual soil loss rate increased from 10.4 (2000) to 12.0 Mg ha−1 yr−1 (2012). Agricultural productivity loss occurred in more than 3 million hectares of crops and silviculture in 2000 and in more than 5.5 million hectares in 2012. Severely eroded areas lost between 13.1 and 25.9 times more nutrients than areas with low and moderate soil loss rates. These findings show that government policy should be directed to ensure the sustainable use of soils, mainly in agriculturally consolidated regions of the Brazilian Cerrado.

Soil erosion is a serious environmental problem that has adversely affected the world's food production through the reduction of land productivity and water availability. The present study estimated annual soil loss rate and its spatial distribution in the most important Brazil's agricultural region, the Brazilian Cerrado, using Revised Soil Loss Equation (RUSLE) model into Geographic Information System (GIS) framework. For this purpose, the soil erosion annual rate was determined in function of RUSLE model factors: rainfall erosivity (R), soil erodibility (K), topography (LS), crop management (C) and supporting conservation practice (P). All factors were obtained from literature. They were processed and integrated into a GIS, resulting in a map of annual soil loss rate. The methodology applied showed acceptable precision and it was possible to identify the most susceptible areas to water erosion. The average estimated rate of soil loss for the entire Cerrado was 12.8 t•ha . Except for annual crops, all farm and silviculture areas showed average soil loss ranging from moderate to high rate. These results suggest that the implementation of more effective management techniques and conservation practices are necessary for the Cerrado to maintain and to improve land productivity by ensuring national and international food demands.

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Unidades de conservação de proteção integral buscam a manutenção dos ecossistemas livres de alterações causadas por interferência humana, admitindo apenas o uso indireto de seus recursos naturais. Portanto, este trabalho estudou a dinâmica do uso e cobertura da terra na unidade de conservação de proteção integral Parque Estadual Monte Alegre (PEMA) do município de Monte Alegre (PA), bem como sua respectiva Zona de Amortecimento, para avaliar a efetividade de sua criação como iniciativa de preservação da biodiversidade local. Foram avaliados produtos de sensoriamento remoto dos anos de 1990, 2001 e 2011, sendo 2001 o ano de criação da unidade em estudo. O resultado permite afirmar que a criação da unidade de conservação PEMA foi importante, uma vez que ao observar dados referentes a dez anos de unidade percebe-se a diminuição do desflorestamento quando comparado ao período anterior à sua implantação. Porém, do ponto de vista conservacionista, tal resultado não é satisfatório, já que fatores que ameaçam a integridade biológica das áreas protegidas não deveriam ocorrer após sua criação.