7 resultados para Gretchen Gfeller

em Deakin Research Online - Australia


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Fish of the genus Gadopsis are a distinctive component of the freshwater fish fauna of south-eastern Australia. Gadopsis marmoratus and G. bispinosus are the only two species recognised within the genus, with the former of uncertain taxonomic status, as it is thought to be composed of at least two distinct geographical forms based on morphological and allozyme data. The objective of this study was to investigate DNA sequence divergence in Gadopsis, especially in the western portion of its distribution, using an approximately 400 base pair fragment of the mitochondrial small subunit 12S rRNA gene region in order to reassess the taxonomy of the genus. Individuals from 11 locations were sequenced and confirm that G. marmoratus and G. bispinosus are genetically distinct, and further that the G. marmoratus complex consists of two divergent clades representing the previously identified northern and southern forms. The degree of divergence between the three Gadopsis clades was similar (5–6% nucleotide substitutions), suggesting that they diverged from a common ancestor at approximately the same period in geological time. These results are consistent with previous allozyme studies and highlight the usefulness of mitochondrial DNA data coupled with allozyme information for clarifying taxonomic boundaries in morphologically conservative aquatic organisms.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In the search for an integrated understanding of the relationships among productive activities, human well-being, and ecosystem functioning, we evaluated the services delivered by a tropical dry forest (TDF) ecosystem in the Chamela Region, on the Pacific Coast of Mexico. We synthesized information gathered for the past two decades as part of a long-term ecosystem research study and included social data collected in the past four years using the Millennium Ecosystem Assessment (MA) conceptual framework as a guide. Here we identify the four nested spatial scales at which information has been obtained and emphasize one of them through a basin conceptual model. We then articulate the biophysical and socio-economic constraints and drivers determining the delivery of ecosystem services in the Region. We describe the nine most important services, the stakeholders who benefit from those services, and their degree of awareness of such services. We characterize spatial and temporal patterns of the services’ delivery as well as trade-offs among services and stakeholders. Finally, we contrast three alternative future scenarios on the delivery of ecosystem services and human well-being. Biophysical and socioeconomic features of the study site strongly influence human−ecosystem interactions, the ecosystem services delivered, the possible future trajectories of the ecosystem, and the effect on human well-being. We discuss future research approaches that will set the basis for an integrated understanding of human−ecosystem interactions and for constructing sustainable management strategies for the TDF.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The article reviews the book "Music, Markets and Consumption" by Daragh O'Reilly, Gretchen Larsen, and Krzysztof Kubacki.