Theme 01: Ecophysiology of Grasslands
Description
The objective of the study was to verify the influence of climatic seasons on botanical composition and on available dry matter of grasslands in the physiographic region known as Serra do Sudeste (Southeastern Range), RS, Brazil. The climate is Cfb according to Koëppen`s classification. The experiment was conducted in two natural grasslands submitted to two pre-experimental stocking rates [area 1: 0.65 AU ha-1 (normal grazing); area 2: over 2.0 AU ha-1 (overgrazing); AU: Animal Unit = 500kg live weight]. Stocking rates throughout the experimental period (June 1996–July 1997) were 0.4 and 0.65 AU ha-1, over winter and the other seasons, respectively. The evaluations were made at the end of each season, using the Botanal package. There was a short forage supply over late autumn/early winter. The two species groupings warm-season grasses (70–78% of total dry matter) and broad leaves (18– 24%) were the main components of the vegetation in the lower layer of the two grasslands. Warm-season grasses had their participation slightly increased during the warmer seasons. The pre-experimental overgrazing of area 2 favoured the contribution of the minor groups cool-season grasses, warm-season legumes and cool-season legumes.
Included in
Seasonal Botanical Composition and Available Forage of Natural Grasslands in the Southeastern Range Region of Rio Grande Do Sul, Brazil
The objective of the study was to verify the influence of climatic seasons on botanical composition and on available dry matter of grasslands in the physiographic region known as Serra do Sudeste (Southeastern Range), RS, Brazil. The climate is Cfb according to Koëppen`s classification. The experiment was conducted in two natural grasslands submitted to two pre-experimental stocking rates [area 1: 0.65 AU ha-1 (normal grazing); area 2: over 2.0 AU ha-1 (overgrazing); AU: Animal Unit = 500kg live weight]. Stocking rates throughout the experimental period (June 1996–July 1997) were 0.4 and 0.65 AU ha-1, over winter and the other seasons, respectively. The evaluations were made at the end of each season, using the Botanal package. There was a short forage supply over late autumn/early winter. The two species groupings warm-season grasses (70–78% of total dry matter) and broad leaves (18– 24%) were the main components of the vegetation in the lower layer of the two grasslands. Warm-season grasses had their participation slightly increased during the warmer seasons. The pre-experimental overgrazing of area 2 favoured the contribution of the minor groups cool-season grasses, warm-season legumes and cool-season legumes.
