Contention one is overfishing Current federal policy impedes offshore aquaculture—ensures the us is dependent on unsustainable sources
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- Photosynthetic microbes mitigate global warming
- Unless fisheries rebound, warming will cause extinction
Warming Add-on2ACAquaculture processes include photosynthetic microbes to reduce environmental impactsBrune et al. ‘03 (D.E., Professor, Bioprocess and Bioenergy Engineering. & State Extension Specialist at the University of Missouri; “Intensification of pond aquaculture and high rate photosynthetic systems” Aquacultural Engineering, Vol. 28, Issues 1–2, pp. 65–86; June 2003, Access: 6/30/14)//ck Aquaculture production systems may range from tanks and raceways, in which water quality is controlled by water dilution and discharge to the environment to captive water systems, in which water quality is controlled by microbial reactions within the tank or pond. Attempts at intensification of pond aquaculture beyond the commonplace practice of supplemental aeration may be classified into categories of physical/chemical techniques and a broad range of microbial techniques. Most of these techniques are directed at raising the ‘ceiling’ of the system ammonia detoxification rate. Physical–chemical techniques for intensification of pond aquaculture have included use of in-pond cages and raceways, water blending and shading of the algal community, as well as, direct flocculation and removal of algal and bacteria biomass from ponds. A variety of microbial processes can be used to reduce ammonia levels in a conventional pond. These processes include nitrification/denitrification, photosynthesis, and heterotrophic bacterial re-growth. In this paper, simplified microbial growth fundamentals, and elemental mass balances are used to analyze and compare the various aquaculture intensification techniques and, in particular, to compare conventional and heterotrophic techniques to the use of high rate photosynthetic systems. Direct or indirect photosynthetic systems include enhanced algal systems (with water mixing), polyculture, hydroponics, wetlands, and terrestrial irrigation/fertilization. The development of Clemson University's Partitioned Aquaculture System (PAS) constitutes an attempt to combine a number of the various physical, chemical, and microbial intensification techniques into a single integrated system. The PAS represents an adaptation of high rate microalgal culture to produce a sustainable, minimal discharge, high yield, and more controllable fish production process. The PAS combines the advantages of process control of recirculating tank aquaculture with the lower costs of earthen pond aquaculture. Central to the economic success of the PAS is the use of low speed (1–3 r.p.m.) paddlewheels as an energy efficient means of establishing a uniform water velocity field within an aquaculture pond. The PAS represents a redesign of the conventional aquaculture pond culture technology providing a spectrum of applications ranging from moderate yield (6700–11 200 kg/ha) ‘engineered ecosystems’ to high yield (16 800–33 600 kg/ha) controlled ‘production processes’. This high rate photosynthetic system offers the potential for a 90% reduction in total water usage per unit of fish produced. The modular nature of the PAS, the increased productivity per unit area, reduced water requirement, and reduced environmental impact offers the potential for fish culture systems to be installed at sites not currently suitable for conventional aquaculture. Photosynthetic microbes mitigate global warmingHuntley and Redalje ‘07 (Mark E. and Donald G., Senior Vice President of Fulton Financial Corp. and B.A. Environmental Biology- University of California, Ph.D. Biological Oceanography- University of Hawaii, Postdoctoral Study- Scripps Institution of Oceanography in marine phytoplankton ecology with biogeochemical cycling of organic materials in the upper layers of the ocean; “CO2 Mitigation and Renewable Oil from Photosynthetic Microbes: A New Appraisal” Mitigation and Adaptation Strategies for Global Change, Vol. 12, Issue 4, pp. 573-608; May 2007; Access 6/30/14)//ck The only major strategy now being seriously considered for biological mitigation of atmospheric CO2 relies entirely on terrestrial plants. Photosynthetic microbes were the focus of similar consideration in the 1990s. However, two major government-sponsored research programs in Japan and the USA concluded that the requisite technology was not feasible, and those programs were terminated after investing US$117 million and US$25 million, respectively. We report here on the results of a privately funded US$20 million program that has engineered, built, and successfully operated a commercial-scale (2 ha), modular, production system for photosynthetic microbes. The production system couples photobioreactors with open ponds in a two-stage process – a combination that was suggested, but never attempted – and has operated continuously for several years to produce Haematococcus pluvialis. The annually averaged rate of achieved microbial oil production from H. pluvialis is equivalent to <420 GJ ha -1 yr-1, which exceeds the most optimistic estimates of biofuel production from plantations of terrestrial ``energy crops.'' The maximum production rate achieved to date is equivalent to 1014 GJ ha-1 yr-1. We present evidence to demonstrate that a rate of 3200 GJ ha-1 yr-1 is feasible using species with known performance characteristics under conditions that prevail in the existing production system. At this rate, it is possible to replace reliance on current fossil fuel usage equivalent to ∼300 EJ yr-1 – and eliminate fossil fuel emissions of CO2 of ∼6.5 GtC yr-1 – using only 7.3% of the surplus arable land projected to be available by 2050. By comparison, most projections of biofuels production from terrestrial energy crops would require in excess of 80% of surplus arable land. Oil production cost is estimated at $84/bbl, assuming no improvements in current technology. We suggest enhancements that could reduce cost to $50/bbl or less. Unless fisheries rebound, warming will cause extinctionUCL News 2014 (Climate change causes high, but predictable, extinction risks; Feb 26; www.ucl.ac.uk/news/news-articles/0214/260214-climate-change; kdf) Judging the effects of climate change on extinction may be easier than previously thought, according to a paper published today in the journal Nature Climate Change. Although widely used assessments of threatened species, such as the IUCN Red List, were not developed with the effects of climate change in mind, a study of 36 amphibian and reptile species endemic to the US has concluded that climate change may not be fundamentally different from other extinction threats in terms of identifying species in danger of extinction. The new study, funded by NASA and led by Richard Pearson of UCL and, formerly, the American Museum of Natural History, and by Resit Akçakaya of Stony Brook University in New York, identified factors that predispose species to high extinction risk due to climate change. By looking at pre-existing information on species of salamanders, turtles, tortoises, snakes and lizards, the team hoped to create a blueprint for judging extinction risk in other species around the world. Dr Richard Pearson (UCL Centre for Biodiversity and Environment Research) said: “Surprisingly, we found that most important factors – such as having a small range or low population size – are already used in conservation assessments. These new results indicate that current systems may be better able to identify species vulnerability to climate change than previously thought.” Through quantitative analysis the team found that across the reptiles and amphibians studied there was a 28% overall chance of extinction by 2100. In contrast, the risk of extinction without climate change was calculated to be less than 1%, suggesting that climate change will cause a dramatic increase in extinction risk for these taxonomic groups over the next century. Dr Resit Akçakaya of Stony Brook University said: "The bad news is that climate change will cause many extinctions unless species-specific conservation actions are taken; but the good news is that the methods conservation organisations have been using to identify which species need the most urgent help also work when climate change is the main threat." The factors identified in this study as predisposing species to high extinction risk due to climate change suggest that conservation actions should focus on species that occupy a small or declining area, have small population size, or have synchronized population fluctuations. The methodology used in this study offers great potential for adaption to additional taxonomic groups and geographical areas, helping to develop effective measures to conserve biodiversity over the coming century. Unlike most previous studies, which predicted future extinction risks based only on projected contraction of areas with suitable climate for each species, the present study estimated extinction risk as the probability of the population size falling to zero by the year 2100. To do this, the authors used a new methodology that included modelling demographic processes such as reproduction, survival, and dispersal. The approach was not designed to make specific predictions for each individual species; instead, the methods allowed the authors to draw conclusions beyond the limited set of species for which data were available. The result is new understanding of the factors that make some species more at risk due to the changing temperature and rainfall patterns that are expected over the coming century. Dr Pearson added: “Our analysis will hopefully be able to help create better guidelines that account for the effects of climate change in assessing extinction risk.” Directory: file -> view view -> Western Europe after wwii view -> Author study: paul fleischman view -> Qpa1 7ela study Guide view -> Arctic Oil/Gas Neg view -> November 1970 Approximately 150,000-500,000 deaths Bhola Cyclone Bangladesh view -> Grade Level: 6 Unit of Study: Caribbean glce view -> Citation: Duffield, Katy view -> Table of Contents Lesson # view -> Chinese Wind Energy Disad Download 0.77 Mb. Share with your friends:
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