Cutover effects of the vegetation and soil in a natural forest

Abstract

The disturbance produced on vegetation and soil after selective and total cutover of two sites were evaluated. The working area is located in Bovril, Entre Ríos, Argentina. It belongs to the Espinal Province, Ñandubay District, which has humid temperate climate and clay, compact and waterlogged soil. The woody structure was evaluated by the linear and fringe transecting methods. Each site was analyzed to study the floristic composition and the Sorensen similarity index (Is) was applied. Forage and weeds productivity was determined. The soil variables: total nitrogen, phosphorous, total organic carbon and others were estimated. The DCA design was continued. Dates was compared through ANOVA and Tukey test with SAS statistic siystem. The mean crown coverage for trees was 56,65 % and 38 % in the monte and the renoval. The tree density was 1,814 individuals ha–1 and 1,120 individuals ha–1 for both areas. The mean tree height was 4,10 and 2,9 m in each case. The shrub stratum presented few species and the herbaceous carpet was composed of Poaceae, Ciperaceae and Compositeae and a great diversity of others families of less importance. The annual forage volume was 3,505 and 3,271 kg M.S. ha–1 in both sites. The M.O., total nitrogen, assimilated phosphorous and nitrate reached higher values in forest vegetation soil than in soil lacking forest vegetation. The total removal of natural vegetation in the second gorwth forest produced a substantial alteration in its herbaceous, shrub-like and tree structure and the soil nutritive level.