Air pollution in a tropical city: the relationship between wind direction and lichen bio-indicators in San José, Costa Rica.

A new method to assess air pollution using lichens as bioindicators.

Lichens are increasingly used worldwide as air quality biomonitors because they are efficient, easy and cheap, but validation studies of the methodology are scarce. Three foliose lichen biomonitoring methods were compared by field tests (in the tropical urban habitat of San José, Costa Rica) and laboratory simulations: (1) the 100 uniform squares template traditionally used in North America, (2...

The influence of air pollution on the phyllosphere microflora composition of Tillandsia leaves (Bromeliaceae).

The effect of air pollution on total phyllospheric microflora from two species of the epiphytic neotropical genus Tillandsia (Bromeliaceae) was studied by comparing unpolluted plants living in a forest (Escazú, San José) with polluted ones from an urban site of Costa Rica (San José city). Dilutions of homogenized leaf samples were plated on media suitable for each microbial group. For each micr...

Conceptualization of the dynamics and synergistic partnership between the agri-food production chain and public health veterinarians

Twenty years of lichen cover change in a tropical habitat (Costa Rica) and its relation with air pollution.

We report lichen cover change over a 20 years period for the Costa Rican capitol city. Foliaceous lichen cover was measured with a 10 x 10 cm template positioned 1.5 m above ground on the south, east, north and west sides of ten phorophytic trees per station (11 stations) from 1976 through 1997. Results were compared with previous measurements along an urban transect (at three heights above gro...

Urban vegetation change after a hundred years in a tropical city (San José de Costa Rica).

Urban vegetation is of key importance because a large proportion of the human population lives in cities. Nevertheless, urban vegetation is understudied outside central Europe and particularly, little is known about the flora of tropical Asian, African and Latin American cities. We present an estimate of how the vegetation has changed in the city of San José, Costa Rica, after about one century...