Evaluating different harvest intensities over understory plant diversity and pine seedlings, in a Pinus pinaster Ait. natural stand of Spain

Although modern forestry takes into consideration the analysis of the effects of forest management on plant structure, diversity and seedlings, little is known about how those parameters respond to harvest techniques in the Mediterranean region. We investigated the effect of three differentharvest intensities, respect to uncut controls, on understory plant species functional groups, richness, diversity and pine seedlings in a natural Maritime pine stand in Spain, three years after harvesting. The harvest treatments produced a reduction of thenumber of Pinus pinaster seedlings and woodyspecies cover, and an increase of species richness(total and of annual species) and plant cover ofannual species respect to control plots (CO). TheShannon diversity values showed no differencesbetween treatments. These results emphasize that the tree harvest treatments analyzed are not suitable for the management of this P. pinaster stand. Otherwise, the reduction of pine seedling density by harvest treatments and the changes in richness and cover of functional groups would not induce the natural regeneration of this stand maintaining the understory plant layer.