A course blog for BIO/EVS/GEOL 476-Issues in Environmental Science @ AU in Ohio
Wednesday, March 30, 2011
A Stinky Invasive
Skunk vine was originally introduced from Asia in the late 1800s. It was going to be used as a fiber crop but it was determined that its weedy properties were going to be harmful for the skunk vine to be used in this manner. It eventually became labeled as an invasive weed because of these weedy properties. The vine is woody and doesn’t contain thorns on its vine. It also has a characteristic stinky smell when it is crushed.
Skunk vine is capable of living in many different types of habitats and can grow very tall, sometimes actually growing up into the canopy of forests it has invaded. Because it is capable of living in many diverse habitats and because it can climb up trees and shrubs, skunk vine can climb up, engulf, and strangle native trees and shrubs. Skunk vine is also capable of reproducing vegitatively or through the use of seeds. Because of this property, it is hard to get rid of.
There have been many different efforts to try to get rid of skunk vine, including physical, chemical, and biological controls. When trying to get rid of this harmful weed, it is a big problem if even stem fragments get transported because new plants can start growing from these fragments. This is one property of skunk vine that aids it in its invasiveness.
There has been a recent discovery of a beetle that could possibly be used for biological control. This beetle, Himalusa thailandensis, was found in Thailand. It was actually found chowing down on a different species of skunk vine that is closely related to the two species that are now invading southern Florida. The way that this new beetle feeds on the skunk vine, it is very detrimental to the plant. Scientists are currently trying to figure out the biology and possible ecological effects of this beetle. They are trying to determine if this beetle would really be a good biological control for eliminating the skunk vine problem in southern Florida.
For some more information on the skunk vine, visit the following website: Center for Aquatic and Invasive Plants
Sunday, March 27, 2011
Algae As The Next Biofuel
Scientists everywhere are brainstorming for the next idea for a better biofuel possibility. A $2 million grant funded under the American Recovery and Reinvestment Act is helping with a project that believes that microalgae would be a good source as a biofuel. Where it would usually take millenia to produce crude oil, this research is speeding that process up to just minutes by heating and compressing the algae. The wastes from this process would be fed on by E.coli, which is also being researched as being used for a fuel source. The only thing that would leave the company would be the oil.
Why use microalgae? These small organisms lack leaves, roots and stems. They also have a weak cell wall, which is easy to break down compared to the other biofuel-potential plant sources. The algae are also carbon-neutral because they consume CO2 regularly and then when used as a fuel that same CO2 that was consumed is released. There is no additional carbon dioxide than what was originally taken in.
So how does the algae become fuel? It is literally pressure-cooked. This is a very simple process where the algae is heated to 300 degrees at a high pressure to keep the algae in a liquid form rather than it being released as steam. This process typically last 30 to 60 minutes until the crude oil is produced. When the algae breaks down due to the high heat and pressure levels, it releases natural oils and proteins which add to the fuel.
Once the crude oil is obtained it is in a tar-like state. The research is currently at this stage in the process, trying to determine how to change the properties of the substance to make it more of a flowing substance that would be easier to put into a car's gas tank. They are also working to clean the substance by reducing its sulfur and nitrogen levels.
An earlier article mentions that there are over 100 companies working on the algae-to-biofuel project and expects it to be a very expensive project. Once all of the technology in in store it will be up to the resource availability of the planet to keep the production of the algae based biofuels proceeding. The major required sources are water, flat land, appropriate climate, and carbon dioxide. It is being considered to use wastewater for the algae production, which helps out both areas respectively. It is expected that algal biofuel could become available within 10 years.
Sources: http://www/sciencedaily.com/releases/2010/04/100422153943.htm
http://www.sciencedaily.com/releases/2010/11/101102131110.htm
Wednesday, March 23, 2011
Wild Colorado
An invasive species is non-native to the ecosystem under consideration, and its introduction causes or is likely to cause economic or environmental harm. They can also cause harm to human health.
New Markets for Wood Waste Products
Lignol Energy Corporation located in British Columbia is looking at the new generation of biofuels. They are making their ethanol the byproduct of an industrial process. The process focuses on the cultivation of a market for the natural glue and lignin that wood pulp contains. It is the lignin that makes the ethanol. However, even with the cost of oil over $100 a barrel, woodbased ethanol isn't commercially competitive. It won't be till the price of oil goes up much higher, or cellulosic ethanol must become cheaper. The company's CEO Ross MacLachlan says "from an industry perspective I think it's fair to say that the cost curve is going to fall over time."
Read more: http://www.vancouversun.com/technology/Biofuel+Lignol+Energy+hunts+markets+wood+waste+products/4454392/story.html#ixzz1HTzYFjJG
Tuesday, March 22, 2011
Follow up on Garlic Mustard (Alliaria petiolata)
Like most invasive plants introduced to the U.S. from Europe and other places, garlic mustard first found it easy to dominate the natives. A new study done in 2009 shows that over time its fungus-killing toxin becomes less potent. The study suggests that evolution can alter the attributes of an invasive plant that give it an advantage over native plants. In fact, the study suggests the plant's defenses are undermined by its own success.
Most plants rely on soil fungi to supplement them with phosphorus, nitrogen and water, however, garlic mustard does not utilize any of this additional help. Instead, garlic mustard produces glucosinolates which are compounds that leach into the soil and kill off many soil fungi, especially those native to North America. This process weakens the native plants because they rely on those soil fungi. As a result, garlic mustard now grows in dense patches and stifle the growth of native plants.
The study focused on answering this question: Once garlic mustard has killed off most of its competitors, why would it invest as much energy in maintaining its toxic components? The team collected garlic mustard seeds from 44 locations, grew them in a greenhouse and tested glucosinolate levels in each. Those tests found that older populations (those that have been present in an area for more than 30 years) produced lower levels of the fungicidal compounds than younger population less than two decades old. Genetic studies suggested that these patterns were the result of natural selection. That is, the plants that produced less of the toxin were more likely to survive and reproduce in older population. The researchers then grew the garlic mustard in soil from native woodlands. After a time, they removed these plants and potted native trees in the same soil. The trees did best in pots that had held plants from older populations of garlic mustard, indicating, again, that the plants' toxin output had diminished over time, killing less of the fungus on which the native plants relied.
While this study focused on only one plant, the results indicate that some invasive plants evolve in ways that may make them more manageable over time. It also provides some information to clarify some questions we discussed about the Garlic Mustard paper in class. We were confused by figure 7 which demonstrated how some plants grew better in soil that was previously inhabited by Garlic Mustard while others didn't do so well. It could depend on how old the Garlic Mustard plants were genetically. If they originated in a area that's been dominated by Garlic Mustard for a substantial amount of time then there would be less toxin in the soil and therefore more growth would be possible.
Tuesday, March 15, 2011
Another Biofuel -- Tequila
A plant commonly known for its role in the production of tequila has been overlooked as a source of biofuel that would not compete with food crops. Agave plants can sustain high yields while enduring extreme temperatures, droughts and carbon dioxide increases, with little need for irrigation, according to a series of papers in a special issue of Global Change Biology Bioenergy. With around 20 per cent of the world semi-arid, and some 200 agave species growing worldwide, utilizing this plant could help combat the potential energy crisis.
Field trials of the biofuel potential of some common Mexican varieties have begun in Australia and there are vast areas of abandoned agave plantations in Africa (once used for sisal fibre production, but abandoned after synthetic fibre production came along) that might be re-established for biofuel uses. This would avoid and economic impact food and would reduce the amount of additional land that would be cleared.
There are two different varieties: Agave mapisaga and Agave salmiana. When produced their energy yields far exceed corn, soybean, sorghum, and wheat productivities; and even without irrigation they still maintain high yields, according to another paper.
Arturo Velez, a former coordinator at the National Confederation of Forestry Producers and head of the Agave Project, an initiative to scale up agave biofuel production in Mexico claims that some varieties produce twice the dry biomass per hectare of hybrid poplar, three times the sugar of sugarcane, and four times more cellulose than eucalyptus, and capture five times more carbon dioxide than the most productive ecosystem. According to Velez, Mexico has 80 million hectares of arid and semiarid areas with no productive potential in which 5,600 million tons of dry biomass could be obtained from agave. This would be enough to meet the United States' transport fuel needs.
Different agave species are already widely used in Mexico for production of tequila and bacanora (traditional drink in Mexico) and henequen fibre (textile fiber made from a native Mexican plant), but in some cases up to 80 per cent of the plant's biomass is being thrown away.
MartÃn Esqueda, a researcher at the Feeding and Development Research Center in Mexico, warned that agave should be sustainably managed to avoid over-exploitation of the wild populations. This has happened with angustifolia species (lavender), which is now endangered because of unsustainable use to produce bacanora according to him.
Monday, March 14, 2011
Waste Water = The New Energy Source?
Most countries spend a substantial amount of time, energy, and money, to treat wastewater so that it will not cause harm to the environment. What if all of this effort could be put into using the waste liquid as an alternative energy source? Wastewater is currently being looked at as a problem rather than a resource. If the energy from this substance can be harnassed and used, it would help water industries become more self-sufficient energy-wise. It would also help those countries that are worse off and who clean water by spending vital resources that they cannont really afford to spare. The U.S. alone uses nearly 1.5 percent of the nation's electrical energy to treat 12.5 trillion gallons of wastewater per year. So, why dump the water after cleansing rather than convert its energy into an energy resource? If this were done, it would no longer be an energy loss to manage waste water, but an energy gain.
The energy in waste water is due to the bonds in the organic molecules, ranging from small, simple chains, to large complex ones. A new freeze-dry technique is being used to recover this energy and it has allowed for better energy recovery. One other study has researched the energy found in waste water. It harnessed 20 percent less energy than what really was present because the freeze-dry technique was not used meaning that there most definitely was loss of some energy-rich compounds due to evaporation.
Sources: http://www.sciencedaily.com/releases/2011/01/110105121131.htm
http://pubs.acs.org/doi/full/10.1021/es103058w
Saturday, March 12, 2011
Current Gas Prices
Thursday, March 3, 2011
Energy of the Future
A satellite is launched into space, but instead of working like a wind mill, where a blade attached to the turbine that is rotated to generate electricity, the satellite would use charged copper wire for capturing electrons traveling away from the sun at several hundred kilometers per second.
- The scientists say that the entire energy generated from solar wind will not be able to reach the planet for consumption as a lot of energy generated by the satellite has to be pumped back to copper wire to create the electron-harvesting magnetic field. However, the amount that reaches earth is more than sufficient to fulfill the energy needs of the planet.
- A team of scientists at Washington State University speculate that it can generate 1 billion billion gigawatts of power by using a massive 8,400-kilometer-wide solar sail to harvest the power in solar wind.
- One billion gigawatts of power could also be generated by a satellite having 1,000-meter (3,280-foot) cable with a sail 8,400 kilometers (5,220 miles) across.
- The scientists feel that if some of the practical issued are solved, Solar wind power will generate the amount of power that no one including the scientists working to find new means of generating power ever expected.
Disadvantages of Solar wind power
But despite the fact that Solar wind power will solve almost all the problems, it has some disadvantages as well.
- Large engineering difficulties will have to be solved before satellites to tap solar wind power are deployed.
- The distance between the satellite and earth will be so huge that as the laser beam travels millions of miles, it makes even the tightest laser beam spread out and lose most of the energy. To solve this problem, a more focused laser is needed.
- But even if these laser beams reach our satellites, it is very doubtful that our satellites in their present form will be able to tap them. The energy is there but there are practical constraints preventing the capture of the energy at this time.