49 resultados para Humid regions.


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Monitoring the abundance and distribution of taxa is essential to assess their contribution to ecosystem processes. For marine taxa that are difficult to study or have long been perceived of little ecological importance, quantitative information is often lacking. This is the case for jellyfish (medusae and other gelatinous plankton). In the present work, 4 years of scyphomedusae by-catch data from the 2007-2010 Irish Sea juvenile gadoid fish survey were analysed with three main objectives: (1) to provide quantitative and spatially-explicit species-specific biomass data, for a region known to have an increasing trend in jellyfish abundance; (2) to investigate whether year-to-year changes in catch-biomass are due to changes in the numbers or in the size of medusa (assessed as the mean mass per individual), and (3) to determine whether inter-annual variation patterns are consistent between species and water masses. Scyphomedusae were present in 97% of samples (N=306). Their overall annual median catch-biomass ranged from 0.19 to 0.92gm-3 (or 8.6 to 42.4gm-2). Aurelia aurita and Cyanea spp. (Cyanea lamarckii and Cyanea capillata) made up 77.7% and 21.5% of the total catch-biomass respectively, but species contributions varied greatly between sub-regions and years. No consistent pattern was detected between the distribution and inter-annual variations of the two genera, and contrasting inter-annual patterns emerged when considering abundance either as biomass or as density. Significantly, A.aurita medusae were heavier in stratified than in mixed waters, which we hypothesize may be linked to differences in timing and yield of primary and secondary productions between water masses. These results show the vulnerability of time-series from bycatch datasets to phenological changes and highlight the importance of taking species- and population-specific distribution patterns into account when integrating jellyfish into ecosystem models.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Courvisanos J., Jain A. and Mardaneh K. Economic resilience of regions under crises: a study of the Australian economy, Regional Studies. Identifying patterns of economic resilience in regions by industry categories is the focus of this paper. Patterns emerge from adaptive capacity in four distinct functional groups of local government regions in Australia, in respect of their resilience from shocks on specific industries. A model of regional adaptive cycles around four sequential phases – reorganization, exploitation, conservation and release – is adopted as the framework for recognizing such patterns. A data-mining method utilizes a k-means algorithm to evaluate the impact of two major shocks – a 13-year drought and the Global Financial Crisis – on four functional groups of regions, using census data from 2001, 2006 and 2011.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

'Raising aspirations' for education among young people in low socioeconomic regions has become a widespread policy prescription for increasing human capital investment and economic competitiveness in so-called 'knowledge economies'. However, policy tends not to address difficult social, cultural, economic and political conditions for aspiring, based in structural changes associated with globalization. Drawing conceptually on the works of Pierre Bourdieu, Raymond Williams, Arjun Appadurai and authors in the Funds of Knowledge tradition, this article theorizes two logics for aspiring that are recognizable in research with young people and families: a doxic logic, grounded in populist-ideological mediations; and a habituated logic, grounded in biographic-historical legacies and embodied as habitus. A less tangible third 'logic' is also theorized: emergent senses of future potential, grounded in lived cultures, which hold possibility for imagining and pursuing alternative futures. The article offers a sociological framework for understanding aspirations as complex social-cultural phenomena, and for capacitating emergent and hopeful aspirations through school- and community-based research and dialogue. © 2013 Philosophy of Education Society of Australasia.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

GPS trajectory dataset with high sampling-rates is usually in large volume that challenges the processing efficiency. Most of the data points on trajectories are useless. This paper summarizes trajectories using stop points. We define a new concept of stay stability (i.e., time dividing distance or reciprocal of speed) between any two GPS points to detect stop points on individual trajectories. We propose a novel Mining Repeat Travel Behaviors Using Stop Regions (MRTBUSR) method. In MRTBUSR, a stop region is a popular region containing a certain number of close stop points that can be grouped into a cluster. We then retrieve common sequences of stop regions to denote repeat route patterns and further analyze the stop durations on a stop region to find repeat travel behaviors. The experiments on 20 labeled trajectories selected from GeoLife demonstrated the semantic effect, accuracy and near linear efficiency of our proposed method.