However, most species were

found only as individual plants in the filtration bed margins with the exception of Urtica dioica (Stinging nettle) in the inflow zone and Epilobium hirsutum (Hairy willowherb) in the outflow zone of several systems. It has been found that the number of “weedy” species decreases with increasing length of operation. In systems, where “weedy” species overgrew the originally planted species, treatment efficiency was not affected. (C) 2013 Elsevier B.V. All rights reserved.”
“We examined vegetation structure and woody species diversity in relation to 14 environmental and anthropogenic factors in ten tropical dry forest (TDF) fragments in central Veracruz, Mexico. The basal area of the canopy (30.2 +/- A 2.11 m(2)/ha) and understory (1.96 +/- A 0.12 m(2)/ha) trees was similar, but density (1,014 +/- A 104 and 2,532 +/- A 227 individuals/ha, respectively) differed among GSK461364 ic50 sites. We recorded 98 canopy, 77 understory,

and 60 seedling species. Richness was 24-45 species per site, Fisher’s alpha and Shannon’s indices increased with site altitude. Chao Jaccard indices revealed high species turnover, and a consistently higher Z-VAD-FMK similarity within the sites at the lowest and within the highest elevation sites. Ordination identified altitude, aspect, slope, water proximity, cattle and trails as significant explanatory variables of species patterns, and showed that sites at lower elevations were clearly separated from the other sites. Environmental heterogeneity alone did not control

species diversity distribution, but species were affected by environmental filters at different stages in their life cycle, e.g., water proximity was significant for saplings and seedlings but not for adults. Anthropogenic disturbances act synergistically, e.g., trails played a key role in determining structure and tree diversity patterns. An important finding is that human disturbance diminishes species selleck chemicals diversity in this TDF, but sites at lower elevations were more disturbed and less diverse, therefore we need to study how environmental factors would act if there were no anthropogenic disturbance.”
“(Seedling morphology of Rhynchosia species (Leguminosae, Papilionoideae) from Roraima, Brazil). This paper aims to describe, illustrate and compare the seedling morphology of the four species of Rhynchosia (Leguminosae, Papilionoideae) that occur in Roraima, Brazil. The studied species, R. phaseoloides (SW.) DC., R. melanocarpa Grear, R. minima (L.) DC., and R. schomburgkii Benth., possess crypto-hypogeal-reserve seedlings, eophylls at the first node that are 1-foliolate and opposite, and double and free stipules. The results show that morphological diversity found among seedlings of the studied species can be used to identify them at the specific level.