99 research outputs found
Developing a predictive modelling capacity for a climate change-vulnerable blanket bog habitat: Assessing 1961-1990 baseline relationships
Aim: Understanding the spatial distribution of high priority habitats and
developing predictive models using climate and environmental variables to
replicate these distributions are desirable conservation goals. The aim of this
study was to model and elucidate the contributions of climate and topography to
the distribution of a priority blanket bog habitat in Ireland, and to examine how
this might inform the development of a climate change predictive capacity for
peat-lands in Ireland.
Methods: Ten climatic and two topographic variables were recorded for grid
cells with a spatial resolution of 1010 km, covering 87% of the mainland
land surface of Ireland. Presence-absence data were matched to these variables
and generalised linear models (GLMs) fitted to identify the main climatic and
terrain predictor variables for occurrence of the habitat. Candidate predictor
variables were screened for collinearity, and the accuracy of the final fitted GLM
was evaluated using fourfold cross-validation based on the area under the curve
(AUC) derived from a receiver operating characteristic (ROC) plot. The GLM
predicted habitat occurrence probability maps were mapped against the actual
distributions using GIS techniques.
Results: Despite the apparent parsimony of the initial GLM using only climatic
variables, further testing indicated collinearity among temperature and precipitation
variables for example. Subsequent elimination of the collinear variables and
inclusion of elevation data produced an excellent performance based on the AUC
scores of the final GLM. Mean annual temperature and total mean annual
precipitation in combination with elevation range were the most powerful
explanatory variable group among those explored for the presence of blanket
bog habitat.
Main conclusions: The results confirm that this habitat distribution in general
can be modelled well using the non-collinear climatic and terrain variables tested
at the grid resolution used. Mapping the GLM-predicted distribution to the
observed distribution produced useful results in replicating the projected
occurrence of the habitat distribution over an extensive area. The methods
developed will usefully inform future climate change predictive modelling for
Irelan
PteridĂłfitas da Serra Negra, Minas Gerais, Brasil
Este trabalho apresenta uma lista de espĂ©cies de pteridĂłfitas que ocorrem na Serra Negra, Minas Gerais. A serra estĂĄ inserida no complexo da Serra da Mantiqueira situada entre Rio Preto, Lima Duarte, Santa BĂĄrbara do Monte Verde e Olaria, tendo seus limites nos pontos 21Âș58'11"S 43Âș53'21" W, 22Âș01'46,4" S 43Âș52'31,5" W, 21Âș58'21,4" S 43Âș50'06,5" W e 21Âș58'53" S 43Âș56'08" W. A vegetação da serra Ă© formada por um mosaico de fitofisionomias, sendo encontradas formaçÔes florestais (florestas ombrĂłfilas e semidecĂduas) e campestres (campos rupestres). O inventĂĄrio florĂstico foi realizado entre os anos de 2003 e 2008, em excursĂ”es mensais para coleta de amostras e registro de dados. Na serra foram registradas 209 tĂĄxons infragenĂ©ricos distribuĂdas em 24 famĂlias e 75 gĂȘneros. As famĂlias com maior nĂșmero de espĂ©cies foram Polypodiaceae (40), Dryopteridaceae (33) e Pteridaceae (25). A maioria das espĂ©cies (109) foi encontrada ocorrendo exclusivamente no interior de floresta. Em relação ao hĂĄbito, 69 espĂ©cies foram encontradas exclusivamente como terrestres, 37 como rupĂcolas ou terrestres e 32 exclusivamente epĂfitas. Este trabalho revela uma elevada riqueza de pteridĂłfitas na regiĂŁo e indica a importĂąncia de estudos desta natureza na conservação e manejo das pteridĂłfitas em Minas Gerais.This work presents an inventory of pteridophyte species that occur in the Serra Negra, of Minas Gerais. The area is part of the Mantiqueira Range, and is situated between the coordinates 21Âș58'11"S 43Âș53'21" W, 22Âș01'4.4" S, 43Âș52'31.5" W, 21Âș58'21.4" S, 43Âș50'06.5" W and 21Âș58'53" S, 43Âș56'08" W. The vegetation in the Serra Negra is characterized by a mosaic of different phytophysiognomies, divided into forests (evergreen and seasonal semideciduous forests) and open formations (rocky grasslands). The inventory was carried out from 2003 to 2008, during monthly excursions to collect botanical material and data in the study area. A total of 209 species, distributed in 24 families and 75 genera, were recorded. The families with the highest number of species were Polypodiaceae (40), Dryopteridaceae (33) and Pteridaceae (25). More than the half (110) of the inventoried species were recorded exclusively in the forests formations. Sixty-nine species were terrestrial, 37 were saxicolous or terrestrial and 32 were epiphytes. This work shows that this region is rich in ferns and reveals the importance of this kind of study for conservation and management of pteridophytes in the state of Minas Gerais
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