Disponibilidade, taxa de acúmulo e oferta de matéria seca do estrato herbáceo em caatinga raleada e enriquecida com capim buffel (Cenchrus ciliares L.) sob pastejo alternado ovino e caprino.

Abstract

The Caatinga biome occupies 74.8% of the Brazilian semiarid region. Goat breeding is one of the main socioeconomic activities in the area, traditionally exploited in extensive or semi-extensive farming systems. Little use is made of vegetation manipulation technologies necessary for environmental and animal sustainability. Thinning, lowering and enriching the caatinga are the most well-known vegetation manipulation techniques in the region. The combination between them, such as thinning + enrichment with exotic species such as buffel grass (Cenchrus ciliaris L.) has increased the quality and availability of herbaceous fodder throughout the year. Studies on alternating goat / sheep grazing in thinned caatinga and enriched with this grass are few developed when evaluating its impact on native herbaceous vegetation. Thus, we sought to evaluate the composition and frequency of herbaceous species, availability and forage supply in an area grazed by crossbred goats and Santa Inês sheep over a period of three years in thinned and enriched caatinga with buffel grass. The work was carried out from a database collected from 2008 to 2010 at Fazenda Lameirão, belonging to the Federal University of Campina Grande, municipality of Santa Terezinha-PB. The species richness in the area was composed of 13 families, 32 genera and 33 botanical species. The average total availability of dry matter was 2,743.95 kg.ha-1. The accumulation rate ranged from 69.55 kg.ha-1 to 205.09 kg.ha-1. The forage supply in dry matter availability was over 195.81 kg.ha-1. The richness of herbaceous species for the area was greater in the first year of evaluation. The frequency (%) of herbaceous species and the availability of dry matter (kg.ha-1) varied according to the months of the year, tending to decrease as the dry season begins. There was no significant variation in the rate of accumulation and in the total supply (kg.ha-1) of dry matter available between the months and years evaluated. Alternating goat / sheep grazing had a reduced impact on native herbaceous species (grasses and eudicotyledons) and did not compromise the environmental sustainability of the area in the analyzed period.