Multicriteria Analysis as a tool for identification of suitable areas to palm oil expansion in Acará River Water Basin, Pará

Abstract

The incorporation of the palm oil crop in Amazonian territory was part of an economic growth idealization bonded to the Amazon, promoted by state and national development plans and programs. The Acará River Water Basin (ARWB) currently represents an important role in the state economy which concerns the production and exportation of palm oil, where each year it has an increase in the areas destined to palm oil crop. The geotechnology, allied to the remote sensing database and processed in the Geographic Information System (GIS), acts as a helper tool for the monitoring, investigation and prevention of the environmental modifications. The Analytic  Hierarchy Process (AHP) is a methodology directed to improve decision making processes when it has multicriteria to be evaluated, generating an validated model which quantifies and ranks the importance of each criteria through stipulated weights. Thus, the aim of this research is to identify and quantify suitable areas for the palm oil expansion in the ARWB, through AHP methodology, and compare the results with the agroecological zoning for palm oil crop (ZAE-palm oil) made by EMBRAPA. The Digital Elevation Model (DEM) was used to delimitate the water basin, extract the drainage network and declivity. The supervised classification of land use and cover of 2020 was made through Sentinel-2 scenes. All procedures involving geoprocessing were performed in software Qgis 3.16.6. With the objective to identify the suitable areas, were determined the criteria that has influence in the aim determination, which are: declivity, roads distance, rivers distance, land use and cover, soil and geology. The areas with excellent suitability occupied 523.91 km², representing 3.87 per cent from the whole basin area. That class correspond to the ideal conditions for the palm oil expansion. The areas classified as good suitability occupied 3,157.62 km², representing 23.33 per cent from the ARWB. The areas without suitability occupied the most of the ARWB, with 6,889.02 km², representing 50.90 per cent. The AHP methodology presented as more efficient and precise in identify suitable areas for palm oil expansion in compare to the ZAE-palm oil, despite the use of different criteria. The combination of AHP methodology and the geoprocessing techniques demonstrated extremely useful in the identification of suitable areas for palm oil expansion in ARWB.