Alocação preferencial de recursos e morfologia de órgãos subterrâneos em plantas resistentes ao fogo em vegetação campestre

Abstract

The underground systems are important for survival of plants and their morphological characteristics have special meaning in environments under disorder. The present study evaluated the existence of preferential allocation of resources in the underground parts of plants resistant to fire and discuss implications of resource allocation and morphology in spatial and temporal dynamics of grassland communities susceptible to fire. The study was restricted to six species of grassland, three monocots (Hypolytrum pulchrum, Echinolaena inflexa and Andropogum sp.) and three eudicots (Euphorbia sarcodes, Eryngium paraguariense and Marcetia taxifolia). The morphological characterizations were performed in about five individuals of each species from anatomical cuts, photos, measurements with digital calipers, tape measures and quantification of biomass share of overhead and underground. The plants showed different spatial arrangements that allow the coexistence in space through a set of skills associated with morphofunctional features integrated aerial and underground parts. Most species showed underground system integrated into networks with preferential allocation of resources to aerial parts, except for E. sarcodes. The morphology is a crucial factor in the competitive responses. The buds developed mainly on rhizomes of plants abundant in these open areas are evidence of the importance of these structures in the dynamics of grassland communities.