%0 Journal Article
%T Perennial grasses traits as functional markers of grazing intensity in basaltic grasslands of Uruguay Rasgos de gram赤neas perennes como marcadores funcionales de la intensidad de pastoreo en pastizales de basalto en Uruguay
%A Martin Jaurena
%A Felipe Lezama
%A Pablo Cruz
%J Chilean Journal of Agricultural Research
%D 2012
%I 
%X Natural grasslands in the basaltic region of Uruguay are threatened by an increase in stocking rates and changes in land use. To assess the effect of grazing intensification, plant functional types are proposed as simple tools to aid the monitoring and management of vegetation. In the present study we evaluated the effect of stocking rate increase at community level taking into account plant traits of 23 dominant perennial grass species. In order to identify plant functional types, we determined the grazing response in an experiment with two wethers stocking rates (0.78 and 1.56 livestock units ha-1) quantifying species cover and traits values. Leaf dry matter content (LDMC) and specific leaf area (SLA) were the traits that best described the perennial grasses response to the stocking rate increase and therefore are suggested to be used as functional markers. Three functional types were identified. Low stocking rates were related to functional type A (tall, warm season species with low SLA and high LDMC and functional type B (tall, cool-season species, with intermediate levels of leaf traits). On the other hand, high stocking rate encouraged functional type C (prostrate, warm season species, with high SLA and low LDMC). The classification of a highly diverse community into three functional types and the selection of traits as functional markers candidates is an innovative approach to develop simple and general methods to diagnosis the state of basaltic grasslands in Uruguay and to advise on its management. Las praderas naturales de la region bas 芍ltica de Uruguay est芍n amenazadas por el incremento de la carga animal y cambios en el uso del suelo. Para evaluar el efecto del pastoreo se han propuesto los grupos funcionales como una herramienta simple para el monitoreo y manejo de la vegetaci車n. El presente estudio evalu車 el efecto del incremento de la carga animal considerando rasgos de 23 especies de gramineas perennes dominantes. Para identificar los grupos funcionales se determin車 la respuesta al incremento de la intensidad de pastoreo en un experimento con dos cargas de capones (0,78 and 1,56 unidades ganaderas ha-1) cuantificando la cobertura de dichas especies y los valores de sus rasgos. El contenido de MS y el 芍rea foliar espec赤fica fueron los rasgos que mejor describieron la respuesta de las gram赤neas perennes al incremento de la carga animal y podr赤an ser utilizados como marcadores funcionales. Tres grupos funcionales fueron identificados. El nivel m芍s bajo de carga animal se relacion車 con el grupo funcional A (especies estivales, altas, con baj
%K praderas naturales
%K diagn車stico
%K manejo
%K carga animal
%K Natural grasslands
%K diagnosis
%K management
%K stocking rate
%U http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392012000400013