Monitoramento da toxicidade genética associada aos dejetos industriais e urbanos em amostras de água do rio Caí através do Teste SMART

O rio Caí é utilizado como corpo hídrico recipiente de efluentes industriais e urbanos. Em função disto,foi utilizado o teste SMART para traçar um diagnóstico da genotoxicidade associada a este rio. As coletasforam realizadas nos meses de março, junho e setembro de 1999 em pontos sob influência industrial(km18,6 e km13,6) e urbana (km52, km78 e km80). Os pontos km 18,6 e km 13,6 foram caracterizadoscomo destituídos de ação genotóxica. Por outro lado, as amostras urbanas referentes aos meses de março(km 52, 78 e 80) e setembro (km 52) foram diagnosticadas como indutoras de toxicidade genética.Considerando estes resultados, conclui-se que os prejuízos causados pelos dejetos urbanos podem ser tãoou mais nocivos que os impostos pelos de origem industrial.Palavras-chaves: SMART, Genotoxicidade, Água, D. melanogaster

Inventory of aspen trees in spruce dominated stands in conservation area

Abstract Background The occurrence of aspen trees increases the conservation value of mature conifer dominated forests. Aspens typically occur as scattered individuals among major tree species, and therefore the inventory of aspens is challenging. Methods We characterized aspen populations in a boreal nature reserve using diameter distribution, spatial pattern, and forest attributes: volume, number of aspens, number of large aspen stems and basal area median diameter. The data were collected from three separate forest stands in Koli National Park, eastern Finland. At each site, we measured breast height diameter and coordinates of each aspen. The comparison of inventory methods of aspens within the three stands was based on simulations with mapped field data. We mimicked stand level inventory by locating varying numbers of fixed area circular plots both systematically and randomly within the stands. Additionally, we also tested if the use of airborne laser scanning (ALS) data as auxiliary information would improve the accuracy of the stand level inventory by applying the probability proportional to size sampling to assist the selection of field plot locations. Results The results showed that aspens were always clustered, and the diameter distributions indicated different stand structures in the three investigated forest stands. The reliability of the volume and number of large aspen trees varied from relative root mean square error figures above 50% with fewer sample plots (5–10) to values of 25%–50% with 10 or more sample plots. Stand level inventory estimates were also able to detect spatial pattern and the shape of the diameter distribution. In addition, ALS-based auxiliary information could be useful in guiding the inventories, but caution should be used when applying the ALS-supported inventory technique. Conclusions This study characterized European aspen populations for the purposes of monitoring and management of boreal conservation areas. Our results suggest that if the number of sample plots is adequate, i.e. 10 or more stand level inventory will provide accurate enough forest attributes estimates in conservation areas (minimum accuracy requirement of RMSE% is 20%–50%). Even for the more ecologically valuable attributes, such as diameter distribution, spatial pattern and large aspens, the estimates are acceptable for conservation purposes