Prioritizing the environmental recovery of the Rio Doce watershed: a fractal approach

Data: 24 Julho, ​entre as 12h30 e as 13h30h
Local: Auditório Florestal do Instituto Superior de Agronomia

Dedicado ao tema “Prioritizing the environmental recovery of the Rio Doce watershed: a fractal approach”, por Raoni Rajão.

Mini CV:
Prof. Raoni Rajão, PhD, Professor Adjunto em Gestão da Produção Sustentável, Bolsista CNPq, LAGESA - Laboratório de Gestão de Serviços Ambientais (coordenador), Dep. Engenharia de Produção, Universidade Federal de Minas Gerais (UFMG)

​The Fundão tailings dam collapse in 2015 combined with a historical deforestation process has led to a critical state of environmental and social vulnerability of the Rio Doce basin in Brazil. The compensatory measures agreed between the companies responsible for the disaster and the public sector includes 40,000 hectares of forest restoration to be implemented by Renova Foundation (a newly created institution created for this purpose) as a way to improve the quality of water supply for the affected population. However, the total area to be restored corresponds to less than 1% of the degraded area of a basin with 8 Mha. In this context, it is paramount the adoption of a landscape restoration planning based on a sound scientific approach to reverse the environmental degradation trajectory in key areas. Here one of the main challenges is the integration of environmental and socioeconomic factors in a transparent and consensual way to guide a prioritization process at different scales (i.e. from the watershed level to the individual rural property). In this study we propose an approach inspired by the fractal geometry concept, a mathematics branch that analysis objects that can be subdivided into parts while maintaining similarities to the original object. In this perspective, we developed three indices that seek to represent environmental vulnerability (IVA), social vulnerability (IVS) and land vocation to environmental recovery (IVR) encompassing the entire watershed. This last index is subdivided into three components, according to the desired forest recovery goal: assisted natural regeneration, restoration plantations (native species) and total planting with economic purposes (agroforestry). VAT, IVS and IVR were calculated with a 30x30 meters resolution (approximately 1 ha), within the census district area (from 0.1 to 34k ha) and the municipality level (from 800 a 318k ha), respectively, seeking the highest-level detail from the input data. Together with a participatory process aiming to define the relative importance of each index for the final prioritization, we generated a spatially-explicit priority index. Our results show a multi scale approach for prioritizing environmental recovery of Rio Doce watershed. In short, the index at the hectare level provides the basis for the development of environmental recovery planning tools at different scales. Starting from the landscape, the index was aggregated at the alternative area of influence to water supply to help targeting 40,000 hectares of forest restoration. The index was also aggregated at the municipality level aiming to facilitate the methodology discussion with the local stakeholders and legitimate the prioritization process. Finally, the index provides a science-based framework to point out priority areas at the micro-watershed and / or census district level to assist local restoration actions. Since restoration planning at different levels started from the same prioritization index, it is possible to guarantee fractal similarity at these different decision-making levels.