Segunda-Feira, 23 de Setembro de 2019, 15:04h

Projeto MapBiomas mapeia três décadas de mudanças na ocupação territorial do Brasil 

Iniciativa que reúne 34 instituições lança coleção inédita de mapas anuais para o período 1985-2017 

The MapBiomas Project has made available today a review of the annual land cover and use maps in Brazil for the period 2000-2016. Collection 2.3 updates the data from Collection 2 released April 2017.

Key aspects of this review include:

Subtitle Simplification – Some subtitle classes, especially at the third level of detail, which had spectral similarities to other classes or were identified only in some biomes were aggregated. The terms for native vegetation classes were also adequate for better comprehension and understanding. The changes aim to make map understanding more practical and straightforward Accuracy Analysis – A complete accuracy analysis of the land cover and land use maps covering each year and subtitle class of their different levels was performed. The overall accuracy of the 2.3 collection was 79.3% at caption level 1, with 9.5% allocation error and 11.2% area error. In the online platform it is now possible to consult the accuracy by class, year, biome and subtitle level.

Time series consistency – Coverage and usage class variations have gained more spatial consistency throughout the time series, reducing noise especially from class transition data between years, due to the adoption of automatic decision trees based on the Random Forest algorithm. 

Simplified access to maps and data for analysis – Several improvements have been implemented in the data access and visualization module that include: (i) comparative classification and two-year image mosaic visualization across the territory; (ii) making coverage maps available each year in a single file for download by biome; and (iii) consolidated coverage and transition statistical data by municipality, state and biomes, available for download in Excel spreadsheet.

These improvements are a consequence of advances in processing algorithms, with emphasis on (i) the inclusion of a new approach to automatic classification that used the results from Collection 2 to train the Random Forest classification algorithm; and (ii) inclusion of new temporal and spatial filtering steps after the thematic map integration process. These advances are described in the algorithm base documents (ATBDs) also available on the platform.

Much of the improvements in this collection were inspired by the demands, criticism and suggestions from MapBiomas Scientific Committee meetings, thematic workshops promoted by the project and, mainly, the contributions of dozens of users of the platform that have used the data for countless applications.

To strengthen this bond with users it is now possible to create an access profile on the MapBiomas platform. From this profile you will be able to create and save maps with the territories of interest and generate a URL to include these maps on their own web pages. This access profile will also allow users to stay current on MapBiomas news.

The MapBiomas team is now working on the preparation of Collection 3 scheduled for release in 2018 with annual land cover and land use maps covering the period 1985-2017.