Nutrient Cycling between Algae and Bacteria Could:- A new study quantifies the bacterial uptake of algae-derived nutrients, as well as the remineralized carbon and nitrogen by algae. Both are important parts of oceanic primary productivity. This project is part of the Facilities Integrating Collaborations for User Science (FICUS) program with the Environmental Molecular Sciences Laboratory and Joint Genome Institute, which are both Department of Energy user facilities.
The global economy requires fossil hydrocarbons to function, from producing plastics and fertilizers to providing the energy required for lighting, heating and transportation. With our increasing population and expanding economy, there will be increased fossil fuel use. As countries improve their gross domestic product per capita, data suggest that their fossil fuel use will increase, and competition for these limited resources will increase.
In addition, there comes increasing atmospheric CO2 concentration, and the potential for significant greenhouse gas-mediated climate change, which now seems likely to affect all parts of the world. Finally, petroleum, which is partially derived from ancient algae deposits, is a limited resource that will eventually run out or become too expensive to recover.
These factors are driving the development of renewable energy sources that can supplant fossil fuels, and allow greater access to fuel resources for all nations, while greatly reducing carbon emissions into the atmosphere.
A number of technologies have been examined as renewable energy sources and, although no single strategy is likely to provide a total solution, it seems possible that a combination of strategies can be employed that will substantially decrease our dependence on fossil fuels. The challenge that remains is to develop renewable energy industries that operate sustainably and can be cost competitive with existing energy options.
Fossil fuels are used for the generation of electrical power, as well as liquid fuels. There are a variety of renewable or low atmospheric pollution technologies that can generate electrical power, including solar, wind, hydroelectric, geothermal and nuclear.
However, renewable technologies to supplement or replace liquid fossil fuels are still in their early developmental stages. The International Energy Agency expects that biofuels will contribute 6% of total fuel use by 2030, but could expand significantly if undeveloped petroleum fields are not accessed or if substantial new fields are not identified.
The most promising sustainable alternatives are almost exclusively categorized under the moniker ‘biofuels’. This term describes a diverse range of technologies that generate fuel with at least one component based on a biological system. The major technologies presently employed for biofuels begin with terrestrial plants and culminate with ethanol, whether this is corn starch to sugar to ethanol, or sugarcane sugars to ethanol.
The regional success of some of these strategies is well noted; in particular, the sugarcane-to-ethanol production in Brazil. To a lesser degree, oils from terrestrial plants – for example, soy and palm – are used to produce biodiesel. These strategies are functional at the small scale; however, as their use has increased, it is evident that they are not sustainable, owing to the enormous amount of agricultural land that would be required to supplant a significant fraction of petroleum using this strategy.
A number of hybrid strategies have been discussed or are currently being deployed. Examples of such strategies include conversion of cellulose to sugars for fermentation into fuel, and gasification of residual biomass into syngas that can then be used to produce liquid fuels. Although each of these strategies is being used to produce fuels, they are insufficient to accommodate the global demand for liquid fuels. Newswise/SP