Plant competition in mediterranean-type vegetation

Plant competition in communities subjected to stress and disturbance is an important ecological issue. We review studies on plant competition in medit erranean-type plant communities in order to discuss its effect on plant- an d plant community structure, to determine the type of competition that take s place and the interaction between competition and effects of fire. Compet ition can intermittently effect all stages of the plant life cycle. Water a nd light seem to be the most frequent resources for which plants compete. C ompetition for nutrients also occurs and seems to be more intense when nutr ient availability is high. Plant interference through allelopathy is also i mportant. Competition may also occur after fire but it is not clear if it i s less intense than in mature stands. As most of the studies have been carr ied out in California. More field experiments that combine the effect of co mpetition and fire along with environmental gradients differing in water an d nutrient levels should be conducted in other mediterranean regions in ord er to draw generalizations on the mechanisms of competition in plant commun ities.