CORTICOLOUS LICHENS AS INDICATORS OF DIFFERENT FOREST MANAGEMENT PRACTICES IN THE DOTALUGALA - KNUCKLES MOUNTAIN RANGE, SRI LANKA

Use of lichens as bioindicators in  tropical zones has been hampered by lack of taxonomic and ecological knowledge. This study was conducted to assess the variation of lichen diversity in different forest management practices under different environmental conditions for their potential use as bioindicators of environmental alterations in Dotalugala, Knuckles mountain range. Data were analyzed to assess the relationship between lichen diversity and microclimatic conditions. In this study, 192 and 148 lichen species were recorded in natural and disturbed vegetation types respectively. The statistical analysis revealed a significant variation in lichen diversity between disturbed and undisturbed vegetations (F = 6.213, df = 1; p ≤ 0.05). Lichen diversity in different vegetation types indicated a remarkable variation (F =3.21, df = 7; p ≤ 0.05). The regression tree analysis indicated, three important variables that determined the lichen diversity; type of vegetation, altitude and association with other Cryptogamic communities. The significant difference of corticolous lichen communities in the natural and disturbed vegetations may be due to the heterogeneity of microclimatic conditions. Specialist lichen communities found to be associated with pristine forests. Results of the present study suggest that lichens in the Knuckles mountain range could be considered as potential indicators in assessing ecological continuity within different vegetations and in the colonization of the regenerating habitats

CORTICOLOUS LICHENS AS INDICATORS OF DIFFERENT FOREST MANAGEMENT PRACTICES IN THE DOTALUGALA - KNUCKLES MOUNTAIN RANGE, SRI LANKA

Use of lichens as bioindicators in  tropical zones has been hampered by lack of taxonomic and ecological knowledge. This study was conducted to assess the variation of lichen diversity in different forest management practices under different environmental conditions for their potential use as bioindicators of environmental alterations in Dotalugala, Knuckles mountain range. Data were analyzed to assess the relationship between lichen diversity and microclimatic conditions. In this study, 192 and 148 lichen species were recorded in natural and disturbed vegetation types respectively. The statistical analysis revealed a significant variation in lichen diversity between disturbed and undisturbed vegetations (F = 6.213, df = 1; p ≤ 0.05). Lichen diversity in different vegetation types indicated a remarkable variation (F =3.21, df = 7; p ≤ 0.05). The regression tree analysis indicated, three important variables that determined the lichen diversity; type of vegetation, altitude and association with other Cryptogamic communities. The significant difference of corticolous lichen communities in the natural and disturbed vegetations may be due to the heterogeneity of microclimatic conditions. Specialist lichen communities found to be associated with pristine forests. Results of the present study suggest that lichens in the Knuckles mountain range could be considered as potential indicators in assessing ecological continuity within different vegetations and in the colonization of the regenerating habitats

Guide to using a lichen based index to nitrogen air quality

This guide provides a simple method for determining gaseous nitrogen pollution that can be used by anyone interested in the impacts of gaseous N on sensitive habitats in the UK. It includes a simple identification key to epiphytic lichens growing on oak and birch that show sensitivity to, or tolerance of, atmospheric N pollution. The lichen species present at your location are used to calculate a lichen indicator score (LIS), which is then converted into a standardised nitrogen air quality index (NAQI), showing the nitrogen air quality at your location.

Citizen science identifies the effects of nitrogen deposition, climate and tree species on epiphytic lichens across the UK

A national citizen survey quantified the abundance of epiphytic lichens that are known to be either sensitive or tolerant to nitrogen (N) deposition. Records were collected across the UK from over 10,000 individual trees of 22 deciduous species. Mean abundance of tolerant and sensitive lichens was related to mean N deposition rates and climatic variables at a 5 km scale, and the response of lichens was compared on the three most common trees (Quercus, Fraxinus and Acer) and by assigning all 22 tree species to three bark pH groups. The abundance of N-sensitive lichens on trunks decreased with increasing total N deposition, while that of N-tolerant lichens increased. The abundance of N-sensitive lichens on trunks was reduced close to a busy road, while the abundance of N-tolerant lichens increased. The abundance of N-tolerant lichen species on trunks was lower on Quercus and other low bark pH species, but the abundance of N-sensitive lichens was similar on different tree species. Lichen abundance relationships with total N deposition did not differ between tree species or bark pH groups. The response of N-sensitive lichens to reduced nitrogen was greater than to oxidised N, and the response of N-tolerant lichens was greater to oxidised N than to reduced N. There were differences in the response of N-sensitive and N-tolerant lichens to rainfall, humidity and temperature. Relationships with N deposition and climatic variables were similar for lichen presence on twigs as for lichen abundance on trunks, but N-sensitive lichens increased, rather than decreased, on twigs of Quercus/low bark pH species. The results demonstrate the unique power of citizen science to detect and quantify the air pollution impacts over a wide geographical range, and specifically to contribute to understanding of lichen responses to different chemical forms of N deposition, local pollution sources and bark chemistry