RESUMO
RESUMO Os corredores ecológicos são importantes estruturas ambientais com a finalidade de conservação e recuperação da biodiversidade em áreas degradadas, decorrentes do desenvolvimento humano desordenado, que favorece a fragmentação florestal e a perda da conectividade entre os diversos habitats naturais. Com a utilização do sensoriamento remoto e de sistemas de informações geográficas, esta pesquisa teve como objetivo identificar áreas com potencial para corredores ecológicos por meio de uma técnica automatizada, o que reduz o caráter pessoal na interpretação visual da imagem. Assim, realizou-se uma análise da conexão entre as Unidades de Conservação presentes na Bacia Hidrográfica do Rio Formoso, Mato Grosso do Sul, mediante a identificação das Unidades de Conservação, das Áreas de Preservação Permanente e dos fragmentos florestais remanescentes. Além disso, foi realizada uma análise da cobertura do solo.
ABSTRACT The ecological corridors are important environmental structures for the biodiversity conservation and restoration in degraded areas, result of uncontrolled human development, which favors vegetal cover fragmentation and loss of connectivity between habitats. With the use of remote sensing and geographic information systems, this research aimed to identify areas with potential for ecological corridors through an automated technique, which reduces personal character in image interpretation. Therefore, a connectivity analysis between the conservation units present in the Formoso River Basin, Mato Grosso do Sul, was performed through identification of Conservation Units, Legally Protected Areas and remaining forest fragments. In addition, a land cover analysis was carried out.
RESUMO
The effect of annual variations in the daily average soil temperatures, at different depths, on the calculation of pesticide leaching potential indices is presented. This index can be applied to assess the risk of groundwater contamination by a pesticide. It considers the effects of water table depth, daily recharge net rate, pesticide sorption coefficient, and degradation rate of the pesticide in the soil. The leaching potential index is frequently used as a screening indicator in pesticide groundwater contamination studies, and the temperature effect involved in its calculation is usually not considered. It is well known that soil temperature affects pesticide degradation rates, air-water partition coefficient, and water-soil partition coefficient. These three parameters are components of the attenuation and retardation factors, as well as the leaching potential index, and contribute to determine pesticide behavior in the environment. The Arrhenius, van't Hoff, and Clausius-Clapeyron equations were used in this work to estimate the soil temperature effect on pesticide degradation rate, air-water partition coefficient, and water-soil partition coefficient, respectively. The relationship between leaching potential index and soil temperature at different depths is presented and aids in the understanding of how potential pesticide groundwater contamination varies on different climatic conditions. Numerical results will be presented for 31 herbicides known to be used in corn and soybean crops grown on the municipality of São Gabriel do Oeste, Mato Grosso do Sul State, Brazil.
