The response of free swimmng marine photosynthetic organisms to changes in the light fiels are complicated , because most utilize upwelling and scattered light as well as the direct rays of the sun in photosynthesis. The modeling results Hardman-Montford et al report recall simulations run at the ERES summer school two years ago.
On Friday, November 1, 2013 12:28:17 PM UTC-4, andrewjlockley wrote: > > http://planetearth.nerc.ac.uk/news/story.aspx?id=1544&cookieConsent=A > > Link above is plain English. Abstract below > > Impacts of light shading and nutrient enrichment geo-engineering > approaches on the productivity of a stratified, oligotrophic ocean > ecosystem. > > Authors > > Hardman-Mountford NJ, et al. Show all > > Journal > > J R Soc Interface. 2013 Oct 16;10(89):20130701. doi: > 10.1098/rsif.2013.0701. Print 2013. > > Affiliation > > Plymouth Marine Laboratory, , Prospect Place, Plymouth PL1 3DH, UK. > > Abstract > > Geo-engineering proposals to mitigate global warming have focused either > on methods of carbon dioxide removal, particularly nutrient fertilization > of plant growth, or on cooling the Earth's surface by reducing incoming > solar radiation (shading). Marine phytoplankton contribute half the Earth's > biological carbon fixation and carbon export in the ocean is modulated by > the actions of microbes and grazing communities in recycling nutrients. > Both nutrients and light are essential for photosynthesis, so understanding > the relative influence of both these geo-engineering approaches on ocean > ecosystem production and processes is critical to the evaluation of their > effectiveness. In this paper, we investigate the relationship between light > and nutrient availability on productivity in a stratified, oligotrophic > subtropical ocean ecosystem using a one-dimensional water column model > coupled to a multi-plankton ecosystem model, with the goal of elucidating > potential impacts of these geo-engineering approaches on ecosystem > production. We find that solar shading approaches can redistribute > productivity in the water column but do not change total production. > Macronutrient enrichment is able to enhance the export of carbon, although > heterotrophic recycling reduces the efficiency of carbon export > substantially over time. Our results highlight the requirement for a fuller > consideration of marine ecosystem interactions and feedbacks, beyond simply > the stimulation of surface blooms, in the evaluation of putative > geo-engineering approaches. > > PMID > > 24132201 [PubMed - in process] > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/groups/opt_out.
