The vegetation types and floristic diversity in the Dominican Republic are analysed, a territory with a tropical climate and ombrotypes that range from dry to humid-hyperhumid, due to the Atlantic winds and the phenomenon known as rain shadows. The presence of high mountains and different substrates have led to a rich flora, and as a result, a high diversity of habitats, among which two large forest types are particularly notable: (1) the dry forest with 81 endemic species, of which 10 are trees, 65 shrubs, 5 climbers and 1 herbaceous species, and an absence of epiphytes and (2) the cloud forest with 19 trees, 20 shrubs, 8 climbers, 4 epiphytes, and 6 herbaceous species. In all cases, these plant communities are regarded as endemic due to their high rate of endemic species. In spite of their importance for conservation, these habitats are highly deteriorated due to deforestation for agriculture, to obtain timber, and even to add to tourism infrastructures.
Part of the book: Vegetation
Our study of mangrove swamps revealed a total of 120 species, of which 13 are characteristics of mangrove swamps, and 38 of flooded areas with low salt. All the others are invasive species which have taken advantage of the degradation of these natural ecosystems. The scenario is not very different in Laguna de Tres Palos in Mexico. The frequent fires in the low-growing semi-deciduous rainforest (dry forest) have caused intense erosion, with the consequence that the site has silted up. As a result, the first vegetation band of Rhizophora mangle is extremely rare. Instead, Laguncularia racemosa and Conocarpus erectus are dominant, along with a band of Phragmito-Magnocaricetea with a high occurrence of Phragmites australis (Cav.) Trin., which acts as an indicator of sediment silting. It is extremely frequent for several reasons: as it is the decrease of the salinity of the water, the scarce depth due to the accumulation of sediments and the contamination by the entrance of residual waters of the nearby populations. When the depth and salinity of the water are suitable, the dominant species are Rhizophora mangle, Laguncularia racemosa, and Avicennia germinans.
Part of the book: Mangrove Ecosystem Ecology and Function