Composition And Structure Of Levee Forests In The Frontal Parana River Delta, Argentina

The Parana River ends in a delta that possesses a native riparian forest of outstanding complexity and richness: the monte Blanco (MB). It is located in the highest sectors of the islands, the levees, and has been practically eliminated and replaced mainly by forest plantations. Likewise, many of these forest plantations have been abandoned giving place to post-abandonment secondary forests (PF) where the processes of invasion of exotic species and of recovery of native species make their classification difficult. The main objective of the research was to describe and compare the vegetation of 2 spontaneously developed levee forests in the Frontal Parana River Delta. Twenty 100 m(2) sampling plots of were set in MB and PF and species presence, cover and tree density were recorded. Both forests resulted homogeneous in the coverage of the main growth forms, but variable in terms of their age and the origin of the species that comprise them. These forests preserve a considerable percentage of the original species and, compared to other delta communities, have greater richness and a markedly different composition. Finally, the classification of these forests is discussed and the generic name "levee forest" is proposed to refer to them.