Dinâmica e relações entre os componentes arbóreo – herbáceo forrageiro em Floresta Ombrófila Mista

Abstract

The objective was to verify the existence of relationships between the herbaceous and arboreal strata in fragments of Mixed Rainforest, in the secondary successional stage and silvipastoral system, located in the municipality of Turvo-PR. Floristic survey data were submitted to phytosociological analysis, forest dynamics, diversity analyzes and Markov Chain. The herbaceous component was evaluated by the Botanal methodology. The climatic variables: insolation, precipitation, solar radiation, minimum, medium and maximum temperature and relative humidity, were submitted to Pearson correlation analysis, together with seasonal dry matter data. The silvopastoral system totaled 594 ind ha-1 and 40 species, the secondary forest 1531 ind ha-1 and 66 species. The phytosociological analysis of 2018 in the silvipastoril system had higher absolute density (AD) for Ilex paraguariensis 225,56 ind ha-1, coverage value (CV) 22.29% and importance value (IV) 19.49%. In the secondary forest, the highest absolute density was Ilex paraguariensis 132.14 ind ha-1, Ocotea porosa with higher cover value 12.38% and value of importance 9.44%. The silvopastoral system area had a periodic increment (PI) of 5.33 m2 ha-1, about 0.88 m2 ha year-1 , and the secondary forest area of 6.11 m2 ha-1, about 1.01 m2 ha year-1. The highest dry matter production occurred in the silvopastoral system area, independent of the season, with the highest production in autumn 245.66 kg DM ha-1, in the secondary forest area the highest production occurred in winter 70.58 kg DM ha-1. Pearson correlation resulted in a negative correlation between biomass of the silvopastoral area and maximum temperature, with a significant correlation between winter biomass in the secondary forest and basal area. It was concluded that the floristic and dynamic parameters between the silvopastoral and secondary forest areas are different, but the similarities indicate that if the silvopastoral system area passes through the isolation process, as well as the secondary forest area, natural regeneration may occur in the same way. The existing production of forage dry matter in the silvopastoral system area is not enough to supply animal feed, reinforcing the need for pasture management strategies so that this area becomes sustainable and productive.