Influence of land use on the water infiltration rate in the Hydrographic Basin of the Streams 54 and 7, Paragominas/PA

Abstract

Infiltration is the phenomenon in which water penetrates in the soil profile due to it being permo-porous, or due to capillarity in non-permeable soils. If the percolation is deeper, the water will contribute to the recharge of the local aquifer. The infiltration rate may be different depending on the type and use and occupation of the soil, the vegetation cover (or lack thereof) or the degree of soil compaction (natural or anthropically induced). The municipality of Paragominas, southwest of Pará, has regions where the combination of different types of soil, vegetation cover, management and maintenance of riparian forest can result in different water infiltration rates, affecting local aquifer recharges. The research evaluated possible changes in the water infiltration rates in the soil in riparian forest, pasture and agriculture areas in the stream 54 and stream 7 comparing them with the dry and rainy periods. Parameters such as granulometry and moisture content of each soil were also analyzed. There was a close relationship between infiltration rate, moisture content, texture and type of soil management. In the riparian forest, the clay type of the soil and the role of vegetation were decisive in low values of infiltration; in the pasture, there were different values of infiltration between drought and rainy seasons, due to the low capacity of moisture retention in the superficial layer of the soil, in addition to compaction due to the trampling of cattle; in the agriculture area (only in stream 54) there was a similar behavior in both seasons, with infiltration rate stabilizing at 60 minutes.