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1.
Conserv Biol ; 24(3): 758-68, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20067490

RESUMO

Species occurrence in a habitat patch depends on local habitat and the amount of that habitat in the wider landscape. We used predictions from empirical landscape studies to set quantitative conservation criteria and targets in a multispecies and multiscale conservation planning effort. We used regression analyses to compare species richness and occurrence of five red-listed lichens on 50 ancient oaks (Quercus robur; 120-140 cm in diameter) with the density of ancient oaks in circles of varying radius from each individual oak. Species richness and the occurrence of three of the five species were best explained by increasing density of oaks within 0.5 km; one species was best explained by the density of oaks within 2 km, and another was best predicted by the density of oaks within 5 km. The minimum numbers of ancient oaks required for "successful conservation" was defined as the number of oaks required to obtain a predicted local occurrence of 50% for all species included or a predicted local occurrence of 80% for all species included. These numbers of oaks were calculated for two relevant landscape scales (1 km(2) and 13 km(2)) that corresponded to various species responses, in such a way that calculations also accounted for local number of oaks. Ten and seven of the 50 ancient oaks surveyed were situated in landscapes that already fulfilled criteria for successful conservation when the 50% and 80% criteria, respectively, were used to define the level of successful conservation. For cost-efficient conservation, oak stands in the landscapes most suitable for successful conservation should be prioritized for conservation and management (e.g., grazing and planting of new oaks) at the expense of oak stands situated elsewhere.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Líquens , Quercus , Técnicas de Planejamento
2.
PLoS One ; 9(11): e112557, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25393951

RESUMO

Inclusion of spatially explicit information on ecosystem services in conservation planning is a fairly new practice. This study analyses how the incorporation of ecosystem services as conservation features can affect conservation of forest biodiversity and how different opportunity cost constraints can change spatial priorities for conservation. We created spatially explicit cost-effective conservation scenarios for 59 forest biodiversity features and five ecosystem services in the county of Telemark (Norway) with the help of the heuristic optimisation planning software, Marxan with Zones. We combined a mix of conservation instruments where forestry is either completely (non-use zone) or partially restricted (partial use zone). Opportunity costs were measured in terms of foregone timber harvest, an important provisioning service in Telemark. Including a number of ecosystem services shifted priority conservation sites compared to a case where only biodiversity was considered, and increased the area of both the partial (+36.2%) and the non-use zone (+3.2%). Furthermore, opportunity costs increased (+6.6%), which suggests that ecosystem services may not be a side-benefit of biodiversity conservation in this area. Opportunity cost levels were systematically changed to analyse their effect on spatial conservation priorities. Conservation of biodiversity and ecosystem services trades off against timber harvest. Currently designated nature reserves and landscape protection areas achieve a very low proportion (9.1%) of the conservation targets we set in our scenario, which illustrates the high importance given to timber production at present. A trade-off curve indicated that large marginal increases in conservation target achievement are possible when the budget for conservation is increased. Forty percent of the maximum hypothetical opportunity costs would yield an average conservation target achievement of 79%.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Ecologia/métodos , Agricultura Florestal , Florestas , Clima , Simulação por Computador , Geografia , Noruega
3.
ISME J ; 7(9): 1696-709, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23575372

RESUMO

Before the recent revolution in molecular biology, field studies on fungal communities were mostly confined to fruit bodies, whereas mycelial interactions were studied in the laboratory. Here we combine high-throughput sequencing with a fruit body inventory to study simultaneously mycelial and fruit body occurrences in a community of fungi inhabiting dead wood of Norway spruce. We studied mycelial occurrence by extracting DNA from wood samples followed by 454-sequencing of the ITS1 and ITS2 regions and an automated procedure for species identification. In total, we detected 198 species as mycelia and 137 species as fruit bodies. The correlation between mycelial and fruit body occurrences was high for the majority of the species, suggesting that high-throughput sequencing can successfully characterize the dominating fungal communities, despite possible biases related to sampling, PCR, sequencing and molecular identification. We used the fruit body and molecular data to test hypothesized links between life history and population dynamic parameters. We show that the species that have on average a high mycelial abundance also have a high fruiting rate and produce large fruit bodies, leading to a positive feedback loop in their population dynamics. Earlier studies have shown that species with specialized resource requirements are rarely seen fruiting, for which reason they are often classified as red-listed. We show with the help of high-throughput sequencing that some of these species are more abundant as mycelium in wood than what could be expected from their occurrence as fruit bodies.


Assuntos
Biodiversidade , Microbiologia Ambiental , Carpóforos/fisiologia , Fungos/fisiologia , Sequenciamento de Nucleotídeos em Larga Escala , Micélio/fisiologia , Madeira/microbiologia , Basidiomycota/genética , DNA Fúngico/genética , DNA Espaçador Ribossômico , Carpóforos/classificação , Carpóforos/genética , Fungos/classificação , Fungos/genética , Micélio/classificação , Micélio/genética , Picea/microbiologia , Madeira/química
4.
PLoS One ; 6(9): e24675, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21961041

RESUMO

Wooded pastures with ancient trees were formerly abundant throughout Europe, but during the last century, grazing has largely been abandoned often resulting in dense forests. Ancient trees constitute habitat for many declining and threatened species, but the effects of secondary woodland on the biodiversity associated with these trees are largely unknown. We tested for difference in species richness, occurrence, and abundance of a set of nationally and regionally red-listed epiphytic lichens between ancient oaks located in secondary woodland and ancient oaks located in open conditions. We refined the test of the effect of secondary woodland by also including other explanatory variables. Species occurrence and abundance were modelled jointly using overdispersed zero-inflated Poisson models. The richness of the red-listed lichens on ancient oaks in secondary woodland was half of that compared with oaks growing in open conditions. The species-level analyses revealed that this was mainly the result of lower occupancy of two of the study species. The tree-level abundance of one species was also lower in secondary woodland. Potential explanations for this pattern are that the study lichens are adapted to desiccating conditions enhancing their population persistence by low competition or that open, windy conditions enhance their colonisation rate. This means that the development of secondary woodland is a threat to red-listed epiphytic lichens. We therefore suggest that woody vegetation is cleared and grazing resumed in abandoned oak pastures. Importantly, this will also benefit the vitality of the oaks.


Assuntos
Líquens/crescimento & desenvolvimento , Quercus/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Madeira/crescimento & desenvolvimento , Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Espécies em Perigo de Extinção , Geografia , Líquens/classificação , Modelos Biológicos , Análise de Regressão , Especificidade da Espécie , Suécia
5.
Mycol Res ; 111(Pt 12): 1366-76, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18023990

RESUMO

The corticioid basidiomycete Peniophorella praetermissa has long been regarded as a morphologically variable species complex. An ITS-based phylogenetic study based on a worldwide sampling was carried out using parsimony and Bayesian inference. The resulting trees feature three major clades, further divided into well-supported subclades. These could be considered as distinct species, a contention that is further supported by crossing test data. Only two out of the eight phylogenetic lineages identified can be distinctly morphologically characterized: P. odontiaeformis and P. subpraetermissa. P. odontiaeformis is an odontioid species with a paleotropical distribution whereas the taxa in the remaining subclades have smooth basidiomata and are distributed in temperate areas. P. subpraetermissa is known only from the type collection and is distinguished microscopically by its reddish brown apically encrustated cystidia. Taxa in the remaining subclades are impossible to distinguish from each other morphologically, and therefore, are viewed as a species complex, P. praetermissa s. lat. One of the subclades, which is widely distributed but restricted to the Northern hemisphere, is proposed to represent P. praetermissa s. str. An epitype is selected from the same area as the holotype, among the specimens studied here. However, the geographically most widespread clade with many representatives from both hemispheres is here referred to as P. pertenuis, a taxon that was previously considered a synonym to P. praetermissa.


Assuntos
Basidiomycota/classificação , Basidiomycota/genética , DNA Espaçador Ribossômico/análise , Filogenia , Basidiomycota/ultraestrutura , Teorema de Bayes , DNA Fúngico/análise , Dados de Sequência Molecular , Técnicas de Tipagem Micológica , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA
6.
Mycol Res ; 107(Pt 6): 645-52, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12951791

RESUMO

Previous studies of morphological variation in the homobasidiomycete Hyphoderma setigerum have lead to suspicions of a species complex. This study explores variation in DNA sequences from the nuclear ribosomal ITS region of 45 specimens from America, Asia, and Europe in a phylogeographic context. Based on molecular analysis, morphological studies, and crossing tests, nine preliminary taxa are shown to exist inside the species complex, and the two previously described segregate species H. subsetigerum and H. nudicephalum are confirmed. The molecular analysis shows evidence of allopatric differentiation over intercontinental distances. Only one of the nine well-supported clades has a geographic distribution spanning more than one continent, probably indicating the importance of vicariance in the evolution of this species complex. The basionym of H. setigerum, Thelephora setigera, is neotypified to fix the application of that name.


Assuntos
Basidiomycota/genética , Basidiomycota/fisiologia , Filogenia , América , Ásia , Basidiomycota/classificação , Cruzamentos Genéticos , DNA Espaçador Ribossômico/análise , Europa (Continente) , Geografia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
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