Microplanejamento de estradas florestais por meio de geotecnologias

Abstract

Forest roads, when are not well structured and allocated, can become potential sources of environmental impacts, mainly related to water dynamics and sediment production. The environmental analyses subsidize the land-use planning which contributes to the control of the undesirable geodynamic processes as the erosion. In this context, the study aimed at the definition of critical areas to forest roads allocation, considering relief, hydrography, and soil characteristics of a landscape (i.e. forest farm of study). We mapped these aspects, that supported the following criteria map generation: slope, erodibility, distance to the flow accumulation water, and aspect. Some criteria were aggregated through Weighted Linear Combination (WLC), a Multicriteria Method (MCE), producing the final map of critical areas to allocated roads, which had its accuracy verified by ROC (Receiver Operating Characteristic) analysis. According to the mapping, the farm was classified in the following levels of criticality: 39,46% high, 29,68% average, 15,61% low, 10,90% very high, 4,14% very low, 0,14% extremely low, and 0,06% extremely high. Yet the roads currently located in the area were classified as the following criticality levels: 37,79% high; 21,78% average; 17,43% low, 15,23% very high; 6,97% very low, 0,43% extremely low, and 0,36% extremely high. The ROC analysis showed a statistically significant accuracy of the mapping, indicating that the criteria represented the critical characteristics of the landscape. We concluded that WLC method can be used in the forest road network planning, considering the critical aspects of the landscape, ensuring its soil and water conservation.