Dimensão de parcelas experimentais

influência nas medidas de escoamento superficial e erosão do solo em Gouveia/MG

Abstract

This article presents the results of a research carried out with the objective of identifying and quantifying the effects of plot size variation on the results of superficial runoff and soil erosion, under the condition of maintaining the natural vegetation cover. Two plots with different size, 100 m2 and 10 m2 , were installed side by side at high, middle and low slope in Gouveia, MG. The area is characterized by a tropical climate with two well-defined seasons: a dry one, occurring during winter in the region (April to September), and a humid one during summer. It presents a relief formed by convex and polyconvex slopes developed on crystalline basement. Each plot was delimited by a 0.4 mm thick aluminum sheet, 33.3 cm wide, 10 cm of which were buried in the soil to prevent sub-superficial addition of water and material coming from upper slope and laterally. Data show that plot size interferes with the results of the runoff and soil losses. There are also evidences indicating that this fact is related to vegetation cover, considered the most important single factor affecting these results. It was detected that this is the only measured parameter that was always at least 10% higher in the 10 m2 than in the 100 m2 plots all over the year.