Monday, September 20, 2010

A Sea of Troubles



Of course this throws open a couple of questions.  The broad fact here is that surface temperatures appear to have increased over the decades.  Presumably that is somewhat a correct assumption.   In the event, there has been a sharp reduction in biological content in these waters.

Again this is data provided by sampling runs and we are assuming consistency that may be unwarranted.   They themselves are cautious in assigning causation

Yet a forty percent shift in surface content is a huge change.  It is interesting that the impact of the temperature is in the stability of the water column and that apparently leads to less biological content.

Yet this does open our eyes to the possibility that the sharp variation in Pacific Salmon is closely related to the annual concentration of plankton in their respective feeding grounds.  I have sensed such a relationship, and the past years declines and recent abundance conforms to just that.

I would like to see massive recovery of the global fisheries and this indicates that the best route will be to map natural feeding grounds and plan methods of stimulating their fertility.

This brings back thoughts of my suggestions for ocean rams that uses a natural pressure differential to lift nutrient rich deep water through a vertical tube to the surface to mix broadly with surrounding surface waters.  This works naturally around sea mounts and produces great fishing grounds.

Knowing the location of natural fish feeding grounds suggest that stimulation is in order.

It is a serious engineering challenge but may not be insurmountable.  The tube itself would not need to be overly engineered and open to innovation.  The momentum entrainment should produce a column of water rocketing out of the top of the tube for distribution.

A sea of troubles

Sep 10, 2010



Nature 466, 1098-1101 (26 August 2010) | doi:10.1038/nature09329; Received 11 March 2010; Accepted 8 July 2010; Published online 28 July 2010

Global patterns and predictors of marine biodiversity across taxa

Derek P. Tittensor1, Camilo Mora1, Walter Jetz2, Heike K. Lotze1, Daniel Ricard1, Edward Vanden Berghe3 & Boris Worm1
  1. Department of Biology, Dalhousie University, 1355 Oxford Street, Halifax B3H 4J1, Canada
  2. Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect Street, New Haven, Connecticut 06520-8106, USA
  3. Institute of Marine and Coastal Sciences, Rutgers University, New Brunswick, New Jersey 08901-8521, USA
Correspondence to: Derek P. Tittensor1 Email: derekt@mathstat.dal.ca

Abstract

Global patterns of species richness and their structuring forces have fascinated biologists since Darwin1, 2 and provide critical context for contemporary studies in ecology, evolution and conservation. Anthropogenic impacts and the need for systematic conservation planning have further motivated the analysis of diversity patterns and processes at regional to global scales3. Whereas land diversity patterns and their predictors are known for numerous taxa4, 5, our understanding of global marine diversity has been more limited, with recent findings revealing some striking contrasts to widely held terrestrial paradigms6, 7, 8. Here we examine global patterns and predictors of species richness across 13 major species groups ranging from zooplankton to marine mammals. Two major patterns emerged: coastal species showed maximum diversity in the Western Pacific, whereas oceanic groups consistently peaked across broad mid-latitudinal bands in all oceans. Spatial regression analyses revealed sea surface temperature as the only environmental predictor highly related to diversity across all 13 taxa. Habitat availability and historical factors were also important for coastal species, whereas other predictors had less significance. Areas of high species richness were disproportionately concentrated in regions with medium or higher human impacts. Our findings indicate a fundamental role of temperature or kinetic energy in structuring cross-taxon marine biodiversity, and indicate that changes in ocean temperature, in conjunction with other human impacts, may ultimately rearrange the global distribution of life in the ocean.

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