Treesearch

Analysis of the extracts of male ants of Monomorium minimum and Monomorium ebeninum by GC-MS and GC-FTIR revealed the presence of tyramides 2 and 4c, for which the structures were established by comparison with synthetic samples. These compounds and their analogues 1 and 3 were also found in males of other Monomorium species, males of Myrmicaria opaciventris, and males of several Solenopsis (Diplorhoptrum) species. Vapor-phase FTIR spectra revealed critically important structural clues to two of the tyramides, which had methyl branching in the tyramide acyl moiety. Tyramide 4c exhibited a...

People’s knowledge of birds and the opinions and perceptions about specific issues related to the conservation of birds were quantified in rural and urban communities in northeastern Puerto Rico. Data were collected using questionnaires in interviews with 131 citizens haphazardly selected within the study site. Our results indicate that urban residents had a significantly higher level of education and were more knowledgeable about the bird species in their neighborhoods than residents of rural communities. However, the knowledge of exotic bird species was similar between residents of both...

Low stature woody vegetation of the south-west coast of Puerto Rico grows on a rocky calcareous substrate where plants can only root in holes, cracks, and crevices accumulating water and sediments that allow seed germination and seedling development. Being in a coastal location these communities are influenced by steady onshore winds, high solar radiation, and salt spray. We studied dwarfed forest communities located at the southern limit of the Gua´nica State Forest, Puerto Rico, that have a well known floristic composition, but with little information on their organization and heterogenei...

Eleven groups of three plots stratified by aspect (windward vs. leeward) and topography (ridge, slope, and ravine) and varying in elevation from 880 to about 1,000 metres were used to sample forest structure and species composition within the dwarf forest of the Luquillo Mountains of Puerto Rico. Stem density to windward was significantly greater on slopes, andf or all topographies combined, than to leeward. The leeward canopy height was significantly greater on slopes, and for all topographies combined, than to windward. In addition, combined mean density declined from ridge through slope...

Six groups of three plots stratified by aspect and topography and varying in elevation were used to sample forest structure and tree species composition within the lower montane rain forest (tabonuco forest) of the Luquillo Experimental Forest (LEF) in Puerto Rico. Stem density, tree height, and total above ground biomass varied by site. Significant differences in canopy height were evident between leeward and windward sites, and declined from ridge to slope to ravine for all sites combined. Total aboveground biomass was significantly greater on ridges than in ravines. Prestoea montana (R....