Mountain forests are an important part of the landscape in our country. In the last three decades they have been seriously damaged by anthropogenic influence, especially immissions. The immissions make worse the health status of Norway spruce (Picea abies) forests, which cause changes in a structure of herbaceous layer, in which the health status of forest stand is reflected. The main goals of my work were to map the cover of herbaceous and mossy layers in two permanent research plots in the Giant Mountains ( Alžbětinka, Modrý důl), to create maps of herbaceous cover, to digitize them and to compare these maps with the extent in years 1993-1994 using a developing analysis in GIS and to detect influence of light conditions on herbaceous layer. Using digitizing and static evaluation of prepared detailed vegetation maps of the both permanent research plots, some important changes were found out in dominant soil cover categories. In the first research plot Alžbětinka, decline of the grass Calamagrostis villosa and increasing of Vaccinium myrtillus cover were evident. In the second research plot Modrý důl, decline of both investigated species, Avenella flexuosa and Calamagrostis villosa, was observed. Another goal of my research was to detect influence of the light conditions on herbaceous layer and nature regeneration of the Norway spruce on permanent research plot Modrý důl. Dependence of the basic categories of the soil cover on the percentual ratio of the light gaps in the crown canopy was proved. Dependence of the height of the seedlings on the ratio of the light gaps was also tested but it was not statistically proved. The negative dependence of survival on the ratio of the light gaps of the seedlings germinated in 1996 was proved, but not of the seedlings germinated in 2004.

The present paper studied the floristic composition, structure and volume of a forest with an area of 120.2 hectares, called Forest Secret Massif, located in the village of Figueira, Segredo s city, Rio Grande do Sul, in order to create the VCA indicator (expanded margin call), RNR indicator (natural regeneration relative) and IRF indicator (forest resilience rating) to describe the representativeness of species in the forest. Also evaluated the phenotypic aspects of the trees and the related of competition at the trees in order to propose a forest restructuring plan by removing mature trees and regenerating trees in order to improve the conditions of the forest and noble species. The three indicators, on a percentage scale, presented able to describe the representation of mature species (VCA), the regenerating species (RNR) and both the forest formation (IRF), which allowed understand the current situation of each species and will understand the changes that may be manifested in the implementation of management plans, obtaining a history. The restructuring plan has listed 13,139 mother trees, 31,820 normal trees and 10,210 trees subject to deletion (group 1), 2.095 noble trees (group 2), 2776 bagueiras (group 3), 4,538 important trees for the forest ecology maintenance (group 4) ; and 24,454 individuals subject to removal for strategic reasons, except the 7,365 needed to stand on environmental issues (group 5). The regenerating forest comes up with 18,430 trees future level 1, 56 415 trees future level 2 and 17,107 trees future level 3. / O presente trabalho estudou a composição florística, estrutural e volumétrica de uma floresta com área de 120,2 hectares, denominada de Maciço Florestal Segredo, situado na localidade de Figueira, no município de Segredo, Rio Grande do Sul, com o objetivo de criar o indicador (valor de cobertura ampliado), (regeneração natural relativa) e (índice de resiliência florestal) para descrever a representatividade das espécies na floresta. Também se avaliou os aspectos fenotípicos e relacionados à competição das árvores com o objetivo de propor um plano de reestruturação florestal por meio da supressão de árvores maduras e de regenerantes, a fim de melhorar as condições da floresta e de espécies nobres. Os três indicadores, em uma escala percentual, se apresentaram capazes de descrever a representatividade das espécies maduras ( ), das espécies regenerantes ( ) e de ambas na formação da floresta ( ), o que permitiu entender a atual situação de cada espécie e permitirá entender as alterações que poderão se manifestar com a aplicação de planos de manejo, obtendo-se um histórico. O plano de reestruturação elencou 13.139 árvores matrizes, 31.820 árvores normais e 10.210 árvores passíveis de supressão (grupo 1), 2.095 árvores nobres (grupo 2), 2.776 bagueiras (grupo 3), 4.538 árvores importantes para manutenção da ecologia florestal (grupo 4); e 24.454 indivíduos passíveis a supressão por motivos estratégicos, salvo os 7.365 necessários a se manter por questões ambientais (grupo 5). A floresta regenerante surge com 18.430 árvores futuro nível 1, 56.415 árvores futuro nível 2 e em 17.107 árvores futuro nível 3.