Soil Chemistry as a Determining Factor for Riparian Reforestation in Paragominas River, Paragominas, Para, Brazil

Changes in riparian forests can be minimized from environmental recovery. However, it is necessary to analyze the soil's chemical attributes before carrying out any recovery measures. Thus, this paper aimed to evaluate the degree of chemical alteration of the land and its ability to supply nutrients to the vegetation for recovery in three areas located in the Permanent Preservation Area (PPA) of the Paragominas River, near three bridges located in the urban area of the municipality of Paragominas, PA. The analytical procedures approach was the deductive one. The research had a quantitative and qualitative technique, besides descriptive objectives. Primary data were obtained in two periods: warm (November) and rainy (February) season, in three areas of 12, 000 m? each, located on the banks of the Paragominas River. Regarding soil chemical attributes analysis, we subdivided the areas into 12 quadrants (4 in each region) of 3, 000m? each. It was then collected one composite sample (500g) of soil in each quadrant, totalizing 12 samples submitted to laboratory analysis. The chemical attributes analyzed were: hydrogen potential (pH), organic carbon (O. C. ), organic matter (O. M. ), available phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), potential acidity (H+Al), total cation exchange capacity (CECtotal), the sum of exchangeable bases (E. B. ) and base saturation (V%). To calculate the degree of soil chemical alteration, we used Factor Analysis with factor extraction by the Principal Component method. The obtained data indicated that the quadrants presented a low (in 33.33%) to a medium degree (66.67%) of chemical alteration. Nevertheless, according to the results obtained, they are consideredsuitable for reforestation since the chemical attributes present sufficient concentrations, enabling plant recovering. We suggest carrying out complementary physical and microbiological soil analysis and phytosociological studies in preserved areas to ensure recovery effectiveness.