Lichens as spatially transferable bioindicators for monitoring nitrogen pollution.

Excess nitrogen is a pollutant and global problem that harms ecosystems and can severely affect human health. Pollutant nitrogen is becoming more widespread and intensifying in the tropics. There is thus a requirement to develop nitrogen biomonitoring for spatial mapping and trend analysis of tropical biodiversity and ecosystems.

Alkaline air: changing perspectives on nitrogen and air pollution in an ammonia-rich world.

Ammonia and ammonium have received less attention than other forms of air pollution, with limited progress in controlling emissions at UK, European and global scales. By contrast, these compounds have been of significant past interest to science and society, the recollection of which can inform future strategies. Sal ammoniac (, ) is found to have been extremely valuable in long-distance trade ( AD 600-1150) from Egypt and China, where 6-8 kg N could purchase a human life, while air pollution associated with collection was attributed to this nitrogen form.

A regional study of the genus (Ramalinaceae) in Asia and Melanesia.

is a crustose to squamulose lichen genus inhabiting the bark of trees in moist tropical forests and rainforests. Species identification is generally challenging and is mainly based on ascospore morphology, thallus morphology and anatomy, vegetative dispersal units, and on secondary chemistry. While regional treatments of the genus have been conducted for Africa, South America and Australia, there exists no study focusing on the Asian and Melanesian species.

Three new species of (Ramalinaceae, lichenised Ascomycota) from the Paleotropics.

Kistenich & Timdal, Kistenich & Timdal and Kistenich & Timdal are described as new species, the first from Borneo and the two latter from New Caledonia. The new species are supported by morphology, secondary chemistry and DNA sequence data. and contain sekikaic and homosekikaic acid, both compounds reported here for the first time from the genus.

Relationships between lichen community composition and concentrations of NO2 and NH3.

The relationship between different features of lichen communities in Quercus robur canopies and environmental variables, including concentrations of NO(2) and NH(3) was investigated. NO(2) concentration was the most significant variable, it was positively correlated with the proportion of lichen cover comprising nitrophytes and negatively correlated with total lichen cover. None of the lichen community features were correlated with NH(3) concentrations, which were relatively low across the site.