Thursday, October 21, 2010
The area consists of five major Southeast Asian basins named; Indus, Ganges, Brahmaputra, Yangtze, and Yellow, each with their own unique characteristics. Yangtze has the largest population, but Ganges is the most densely populated. Indus and Brahmaputra have vast amounts of upstream areas and larger glacier areas. And the Yellow and Indus basins are dryer than Ganges, Brahmaputra, and Yangtze. Fig.1 depicts this area which ranges from low (dark green) to high (brown) elevations and blue being elevations 2000 m above sea level. These rivers provide water to more than 1.4 billion people, which is 20% of the world’s population.
Results from an analysis show that the present melt-water plays an important role in the Indus and Brahmaputra river basins. It is most evident in the Indus because the water generated from glacial and snow melt is 151% of the total water naturally caught in downstream areas, whereas the Brahmaputra basin had a percentage of 27%. Meanwhile the contributions to Ganges (10%), Yangtze (8%), and Yellow (8%) are much smaller due to a much limited amount of upstream areas, and more downstream rivers which catch more rainfall.
It is commonly known that glaciers around the world have been reducing in size since the last ice age, and two tests have been done in order to see the differences between a) a best guess of the five major glaciers from today’s date to 2050, and b) an extreme case, in which there are no glaciers. Results show that although there is a decrease from the upper rivers; Indus (-8.4%), Ganges (-17.6%), Brahmaputra (-19.6%), and Yangtze (-5.2%), there was an increase in upstream rainfall; Indus (25%), Ganges (8%), Brahmaputra (25%), Yangtze (5%), and Yellow (14%). Analysis even showed an increase of 9.5% is the Yellow basin because its river is in the downstream and so it barely depends on glacial and snow melt.
It is said that climate change may cause some basins such as Ganges, Indus, and Brahmaputra to become more seasonal, because of the reduced amount of glacial melt, and increase of rainfall. The Yellow basin is expected to become the most, it has been already reported that it shows a consistent increase in accumulation in early spring. Glacial and snow melt caused by climate change will increase in the spring, causing an alleviated drought later in the season.
Regardless of the good effects of rainfall, the Indus and Brahmaputra are expected to reduce considerably in water amounts, due to climate change, causing and accelerated glacier melt and faster river flow. And it shows that this will have an effect on food security. An estimation of 4.5% is expected to be the total population which will be threatened from the reduced water availability.
It is clear then that the Indus and Brahmaputra basins are the most sensitive to food security and downstream water supply. The results of the scenario of a lower amount of downstream water and irrigation were the highest with these two basins. In conclusion, the water towers of Asia are threatened by climate change in the coming years. Although a generalized answer cannot be given because the results differ substantially from basin to basin, there will be an effect. It can be said though, that the Indus and Brahmaputra basins will feel this change the most, mostly because of their high population and density numbers, and their reliance on the river for irrigation and food supply. In the case of the Yellow river, is seems that climate change may have a positive effect. This is because it has a low dependence on glacial and snow melt, and with an increase in upstream precipitation, may even yield positive numbers. If it were retained in reservoirs it would allow for greater water availability, irrigation options, and food supply.
Immerzeel, W.W., van Beek, L.P.H., Bierkens, M.F.P. 2010. Climate change will affect asian water towers. Science, 328 (11 June 2010): 1382-1385.
Thursday, October 14, 2010
Abdullah lived in Sukkur, a village in the northern parts of Pakistan. He lived in a hut which was part of a village built on low land; he earned a living by planting crops on land near the river bed and by herding buffalo. Although Abdullah was warned of the dangers of flooding, and had faced waters many times in his seventy years, he was not prepared for what was to follow. Today he sits in a graveyard with only a sheet tied between two tombstones to protect his family. His crops were washed away, and he lost all his buffalo even though he moved them to higher ground as a precaution.
Tragic stories like these are unfortunately becoming more common, leaving one to wonder why and how they happen. A question many of us would like the answer to.
Pakistan is one of the most natural disaster-prone countries in the World (40% of landmass is vulnerable to earthquakes, 6% to cyclone, 60% to floods, and 25% of land under cultivation is vulnerable to drought). The heavy rainfall, weak geological formations, accelerated rates of erosion and very high seismicity makes the unique geo-environmental setting of the north Himalayas prone to disasters. Considering this, and the comparative inaccessibility, the North region demands special attention to minimize loss of lives and to ensure sustainable development. An important note to be made is that the 2010 floods are historical in terms of magnitude and range. The country is exposed to floods almost every year but the recent floods break all records of the past. A bird’s eye view of the situation would show the loss of the countries’ food basket, loss of livelihood, loss of infrastructure and most importantly the displacement of 20 million people. Damages like these cannot be recovered or rehabilitated in a short time period.
Similar floods have struck China, Bangladesh, Vietnam and India recently. There are many factors that contribute to these rapid changes in environmental patterns, predominant ones include the melting of glaciers, Environmental degradation, and Climate Change.
The melting of glaciers all around the world is leading to the formation of excessive bodies of water and contributing to sea level rise. This potential hazard for floods makes water management in forms of dams and canals important, especially in third world nations.
Environmental degradation in countries like Pakistan is also a leading cause of floods. Deforestation, wild land fires, water and air pollution, and desertification are all examples of environmental degradation. To further complicate the matter, soil erosion occurs when clear cut land is exposed to the sun, making it very dry and eventually infertile, due to the volatile decrease in nutrients like nitrogen. Landslides triggered by floods are responsible for taking many lives.
It is a well-known fact that global warming is being caused largely due to emissions of greenhouse gases like carbon dioxide into the atmosphere. However, it is not quite as well known that deforestation has a direct association with carbon dioxide emissions into the atmosphere. Trees absorb carbon dioxide from the atmosphere to produce carbohydrates, fats, and proteins that make up trees. When deforestation occurs, many of the trees are burnt or not allowed to rot, which results in releasing the carbon that is stored in them. This, in turn, leads to greater concentrations of carbon dioxide in the atmosphere.
The direct correlation between warmer temperatures and global average precipitation signifies the importance of the stability of the environment in relation to floods.
Urbanization has increased society’s vulnerability to floods. The public needs to be educated that floods cause much human suffering and infrastructure damage in a short span of time. This knowledge should further reflect on our actions towards the environment. The rise in natural disasters should be considered a wake up call to start appreciating the environment instead of testing its limits
"Structural Causes of Vulnerability to Flood Hazard in Pakistan* - Mustafa - 2010 - Economic Geography." Wiley Online Library. Web. 15 Oct. 2010.
In their extensive study the researchers had two main questions; do introduced species affect the biodiversity (i.e. variety, abundance and evenness of species) within a native plant community? And, if there is an effect, what factors contribute to their success?
To answer these questions they selected sites with meadow ecosystems, throughout the Czech Republic, in which the thirteen chosen invasive species were present. For each site, two 16 m2 areas, adjacent to one another, were sectioned off with one displaying heavy invasion and the other displaying little to no invasion. Over a period of four years a total of 260 vegetation plots were monitored.
With all of the data collected they calculated, using statistical analysis, the similarity between each pair of plots and each plots community characteristics including species richness, impact of invasion on diversity, invader’s height and percent cover, and differences between the invading and native dominant species.
As usual the results are complicated. No invasion will be identical every time so it was important to gather data from many different environments to compare the variable responses of plant communities with and without invasions. The short answer is that yes invasive species affect biodiversity and there are roughly five main factors that contribute to the success of invasive species. The longer answer is that not all invasive species actually had a negative impact on the plant communities but for those invasive species that did have an impact there was a decrease in the variety and abundance of species but the factors contributing to this were species specific. Each of the thirteen species impacted the communities differently. Some invaders reduced species numbers by up to 90%, whereas, other invaders had little to no impact on species numbers.
There are five factors for successful invasion and depending on the species these factors differ in importance. 1) Grow tall and fast, 2) Possess large cover to obtain the most light and block out the sun from other small species, 3) Develop extensive root systems underground to take-up water and nutrients and block competitors, 4) Form a homogeneous stand, and 5) Invade community where you can outcompete. There are always exceptions and sometimes an invasion can be successful without competing with the dominant native species or creating a monoculture. For example, Impatiens glandulifera invade riparian zones where they cannot compete with the dominant native species. They may not decrease species abundance but they can decrease species diversity.
Sometimes how we gauge an invasion is based on how valuable the area is to us. Fallopia species and Solidago gigantea tend to invade areas with lots of weeds, whereas Heracleum mantegazzianum and Lupinus polyphyllus can invade nutrient poor sites where many rare species can be found. From a conservation perspective, the weed infested area may be less valuable than the area supporting rare species.
Although studies like this can provide guidelines for evaluating similar habitats and their risk for invasion, the intricate dynamics of these natural systems and each organism’s uniqueness may continue to keep us guessing.
Hejda, M., Pyšek, P. and Jarošik, V. 2009. Impact of invasive plants on the species richness, diversity and composition of invaded communities. Journal of Ecology. 97:393-403.
Expansion of biofuel crops is thought to conflict with land availability, necessity for animal feed, and environmental concerns such as biodiversity and greenhouse gas emissions. While these complications should not and cannot be overlooked, the potential benefits of efficient biofuel production must be seen as both necessary and achievable by society. In an attempt to harmonize the need for such fuels, animal feed, and environmental concern, Dale et al. analyze possible modification to the agricultural industry.
AFEX is a process that has been shown to significantly increase fermentable sugars produced in biofuel production, thereby increasing biofuel land-efficiency. This beneficial treatment can also create a more digestible, more protein rich animal feed. This has been shown with the successful addition of AFEX-treated feed to the diets of dairy cows (Weimer 2003). LPC is a protein rich material created by the extraction of juice from fresh plant material. It can be used for both animal feed and biofuel production, and it has been extensively tested for many years. A final agricultural technology considered by the team is double-cropping. This is a process where farmers plant winter crops, such as grasses or legumes, increasing the quality of the soil by increasing the total biomass. This also prevents weathering during the winter season. Animal feed in the United States currently requires over 80% of the total crop production in the country. From this, rises the need for more farmland-efficient technologies. Two such technologies, ammonia fiber expansion (AFEX) and leaf protein concentrate (LPC), are analyzed here. In order to estimate the environmental effects of applying these technologies, the team models carbon and nitrogen dynamics from climate and earth data. Through this model, soil carbon levels, total biomass production, and emissions associated with nitrogen are predicted. Simulations occurred for each crop at nine separate areas in the Midwestern United States for a duration of 60 years. Averaged results from each crop system were used to estimate the environmental effects of each. Also, changes in greenhouse gas emissions from the total production process were determined. The results of this analysis show a general trend. Applying these crop technologies result in traditional amounts of animal feed production, while significantly increasing biofuel production and successfully reducing greenhouse gas emissions in agricultural processing. Works Cited: Biofuels Done Right: Land Efficient Animal Feeds Enable Large Environmental and Energy Benefits Environmental Science & Technology Biomass Conversion Research Laboratory, Department of Chemical Engineering and Material Science, and Great Lakes Bioenergy Research Center, Michigan State University, 3815 Technology Blvd Suite 1045, Lansing, Michigan 48910, United States
AFEX is a process that has been shown to significantly increase fermentable sugars produced in biofuel production, thereby increasing biofuel land-efficiency. This beneficial treatment can also create a more digestible, more protein rich animal feed. This has been shown with the successful addition of AFEX-treated feed to the diets of dairy cows (Weimer 2003). LPC is a protein rich material created by the extraction of juice from fresh plant material. It can be used for both animal feed and biofuel production, and it has been extensively tested for many years. A final agricultural technology considered by the team is double-cropping. This is a process where farmers plant winter crops, such as grasses or legumes, increasing the quality of the soil by increasing the total biomass. This also prevents weathering during the winter season.
Animal feed in the United States currently requires over 80% of the total crop production in the country. From this, rises the need for more farmland-efficient technologies. Two such technologies, ammonia fiber expansion (AFEX) and leaf protein concentrate (LPC), are analyzed here.
In order to estimate the environmental effects of applying these technologies, the team models carbon and nitrogen dynamics from climate and earth data. Through this model, soil carbon levels, total biomass production, and emissions associated with nitrogen are predicted. Simulations occurred for each crop at nine separate areas in the Midwestern United States for a duration of 60 years. Averaged results from each crop system were used to estimate the environmental effects of each. Also, changes in greenhouse gas emissions from the total production process were determined.
The results of this analysis show a general trend. Applying these crop technologies result in traditional amounts of animal feed production, while significantly increasing biofuel production and successfully reducing greenhouse gas emissions in agricultural processing.
Biofuels Done Right: Land Efficient Animal Feeds Enable Large Environmental and Energy Benefits
Environmental Science & Technology
Biomass Conversion Research Laboratory, Department of Chemical Engineering and Material Science, and Great Lakes Bioenergy Research Center, Michigan State University, 3815 Technology Blvd Suite 1045, Lansing, Michigan 48910, United States
Almost a third of the world’s energy is used as fuel for transportation vehicles, and the decreasing amount of fuel reservoirs remaining has caused serious uproars among politicians as well as environmentalists. According to Taner and Ayhan Demirbas, the solution to these issues resides in biomass and biofuels. Their hope is that someday biofuels will replace traditional petrol and gasoline used which have detrimental effects of the environment. Biofuels are referred to as a liquid or gaseous fuel that are mostly made of biological material from living or recently living organisms. This biological material is called biomass which is comprised of all vegetable material, and usually consists of materials derived from growing plants and animal manure. Biofuels can be made of many different products including corn stalks, rice straw, pulpwood and even municipal solid waste. The Demirbas have been researching the effectiveness and ways to better convert biological material into usable transportation fuel.
There are many advantages to replacing traditional petroleum fuels with biofuels. For example, bioethanol, the most common biofuel can be made of several common products such as wood, straw and even household wastes. The environmental impact of extracting fuel could be greatly reduced were the majority of people to switch to bioethanol for their transportation fuel needs. Biofuel can be used in transportation vehicles which then emit carbon dioxide as exhaust instead of harmful greenhouse gasses. This cycle is depicted in the diagram below;
Potentially, someday biofuel could supply the demand for transportation fuel for the majority of cars, busses, trains and even airplanes. Converting to sustainable biofuels instead of extracting crude oils would greatly reduce the amount of toxins released into the air; with this in mind one must wonder why the use of biofuels for our transportation needs is not more mainstream. Unfortunately, there are also a few inconveniences associated with the use of biofuel. For example, the production price of biofuel in developed countries is approximately three times greater than that of petroleum fuel. Along with the cost setbacks, there are still several kinks to be worked out in the production of biofuels. The production of biofuels is a relatively new science and therefore the production of biofuels is not nearly as effective as that of traditional transportation fuels which have been around for a far greater period of time. Biofuel production began only in the early 1990’s but didn’t gain popularity or recognition as a potential solution to the world’s transportation fuel crisis until recent years. As the need for a new source of transportation fuel is increasing, the more popularity biofuel is gaining. Along with this popularity is increased scientific innovation to improve the production rates of biofuels. Even with these new technologies converting biomass to biofuels more efficiently than before, it is still no comparison to the efficiency of extracting petroleum. It’s for these reasons that petroleum is still the primary source of transportation fuel. However, there is still hope for future generations; progress is being rapidly made which has in turn increased production capacity and the amount of materials required to produce biofuels.
Solutions to these hurdles that must be overcome before biofuels can begin to replace traditional diesel and petrol are becoming more and more apparent as the demand for more environmentally friendly transportation increases. Biodiesel, another type of transportation fuel created from biomass can be used in any modern diesel engine without modifying the engine. Soon, perhaps all types of biofuels will simply be able to replace our gas needs with no modifications to our vehicles.
Overall, more research is required before the switch from traditional petrol and diesel fuel to biofuel can occur. This switch will result in less consumption of crude oils as well as minimize the amount of greenhouse gasses released into the atmosphere from transportation vehicles. With such significant and promising outcomes it’s only a matter of time before biofuels replace traditional transportation fuels.
Demirbas, A.H., Demirbas, T. (2010). Bioenergy, green energy; biomass and biofuels. Energy Sources Part A: Recovery, Uitilization & Environmental Effects, 32: 12, 1067-1075
The study published in Environment Impact Assessment Review, was conducted by researchers from Leibniz-Centre for Agricultural Landscape Research (ZALF), Institute of Socioeconomics, a, Germany.
Fuel switching from wood to LPG can benefit the environment
Sunil Nautiyal ⁎, Harald Kaechele (2008)
Environmental Impact Assessment Review 28 (2008) 523–532
Peter Ross and a team from all over Canada issued a recent study in the Marine Pollution Bulletin in 2009. The study was conducted concerning a chemical called polybrominated diphenyl ethers or PBDE’s and its effects on aquatic life. The chemical in question is commonly used as a flame retardant in industrial manufacturing of foam mattresses and furniture (Ross, et al., 2009). The chemical is generally sold in three forms: Penta, Octa and Deca. PBDE’s are structurally similar to PCB’s and have to potential to harm food chains and ecosystems in similar ways to PCB’s. The forms of Penta and Octa have been realized as a harmful and were removed from the market places in Europe in 1998 and from North America in 2004 (Ross, et al., 2009). The third form deca remains unregulated in Europe, Canada and the United States (Ross, et al., 2009).
source:(Ross, et al., 2009)
The main component in the deca-BDE is BDE-209 congener (a congener is one of many variants of a common chemical (Green Facts)). The article outlines the authors concerns about the effects of BDE-209 and its persistence, bioaccumulation, toxicity and the possibility of long-range environmental transport and its continued widespread use in North America (Ross, et al., 2009).
The study found that BDE-209 is persistent in the environment. The chemical is transported by means of water pathways, including wastewater, landfill leaching and atmospheric deposition (Ross, et al., 2009). The PBDE’s do not readily break down and their presence in the environment can be traced by depth profiling. From looking at samples taken, it is clear that the presence and concentrations of the chemical mirror its manufacturing history. As surface sediments are mixed with contaminants of PBDE there is a chance that it will re-enter the aquatic food webs and therefore continue to build up rather than being buried under more sediment (Ross, et al., 2009).
The concentration of PBDE in marine mammals can double within 3-4 years in some areas (Ross, et al., 2009). In other areas the contamination puts at risk species on the lower and upper levels of the trophic aquatic food chain (Ross, et al., 2009). The presence of the PBDE’s the body have very similar effects as the structurally similar PCB. PCB's were discontinued in the 1970’s and remain in the environment today. Exposure to PCB’s has been linked to cancer and complications with the immune, respiratory and nervous systems (Groc, 2005). Long-range environmental transport is also a major concern. The study found that PBDE’s are found in remote locations around the world including the Canadian arctic (Ross, et al., 2009).
PBDE is rapidly becoming the new PCB of the world. It reacts similar in the environment and increasing rapidly in concentration in biotic and abiotic materials (Ross, et al., 2009). The concentrations in sewage sediments and water near urban parts of Canada has surpassed the levels of PCB and is projected to become the highest contaminant in fish and marine mammals within ten years if something is not changed (Ross, et al., 2009). The most eye opening concept of the study is that even if production and distribution of deca-PBDE is put to a stop today, there is enough of it already in circulation to ensure the continued delivery to the environment, and therefore the unregulated flame retardants known as PBDE’s with continue to circulate through the environment and into the aquatic food chains for decades (Ross, et al., 2009).
Green Facts. (n.d.). Glossary. Retrieved from Green Facts: http://www.greenfacts.org /glossary/abc/congener.htm
Groc, I. (2005, November 1). PBDE’s: From the household to the ocean. Retrieved October 12, 2010, from Wild Whales: http://wildwhales.org/?p=159
Ross, P. S., Couillard, C. M., Ikonomou, M. G., Johannessen, S. C., Lebeuf, M., Macdonald, R. W., et al. (2009). Large and growing environmental resevoirs of Deca-BDE present an emerging health risk for fish and marine mammals. Elsevier (58).
Increasing global temperatures are expected to increase the occurrence of extreme heat events (EHEs) such as heat waves. These events are the cause of hundreds of deaths each year in the Unites States, particularly in the old, young, ill, and homebound. Heat related deaths occur most often in cities as a result of what is called the urban heat island effect, through which urban areas experience higher temperatures in comparison to surrounding rural area. This effect is caused by lack of vegetation, surfaces that reflect heat (pavement for example), and building layouts that trap heat. In the last half century, cities have been growing in a way that has increased area and decreased land-use density. This pattern is called urban sprawl. Urban sprawl has been associated with higher surface temperatures in cities, which has provoked research into the correlation between urban design and the probable occurrence and intensity of EHEs; which would be a direct link between human health and our activity towards the environment.
To determine if urban sprawl does in fact increase the occurrence of EHEs, a team of researchers from the Georgia institute of technology and Emory University looked at increasing rates of EHEs in different metropolitan centres over within the past five decades (1956-2005). To relate the data on EHEs to urban sprawl, the researchers used a sprawl index to quantify land-use in the cities studied. This index was based on connectivity, centeredness, density, mix of land uses. Data on EHEs was taken from a National Climatic Data Centre heat stress index, which describes an EHE as any time that apparent temperature is greater than the 85th percentile of the base period. Only cities which had recorded EHE data for at least 42 of the 50 year period were used in statistical analysis. Yearly changes in occurrences of EHEs were averaged for each city and the correlation with the sprawl index was measured (influence of population size and growth was controlled in analysis).
The study found that EHEs have been occurring more frequently in all cities looked at, increasing at a yearly rate, such that on average, a city experienced 10 more EHEs in 2005 than in 1956. Cities that fell in the top quartile on the sprawl index saw an increase in events by 14.8 days, whereas cities that fell in the bottom quartile only saw an increase of 5.6 days. These findings confirmed that there is some connection between urban sprawl and increased rate of EHEs observed.
The authors of the report suggest that a possible cause of this relationship is the effect urban sprawl has on vegetative land cover. Between 1992 and 2001, regions in the top quartile or the sprawl index more than double the area of forests compared to those in the bottom quartile.
The findings of this study tell us that we should be reconsidering the manner in which we expand and develop our urban areas, and should be taken into consideration for future development. Decreasing urban sprawl and adjusting to a more compact urban design can help decrease the number of EHEs. Some things that can be done to lesser the magnitude of the urban heat island effect include the use of more reflective surfaces, use of green roofs, integration and preservation of vegetation, and decreasing the dependency on vehicular travel. Not only will these strategies decrease temperature spikes in urban settings, but can also decrease pollution, promote physical activity and thus decrease obesity, and decrease road traffic injuries.
The study only looked at the occurrence of EHEs compared to the urban sprawl index and did not look at heat-related mortality. The authors note that incidences of heat-related deaths and injuries in the United States have remained fairly level despite rising temperatures. This could be explained by the presence of protective factors such as air conditioning in homes. However he authors note that if the effects of urban sprawl continue to increase, our ability to counteract them on a personal level stating that “as Shanghai’s urban heat island has grown, heat related mortality rates have increased. This finding suggests that there is the potential for a similar trend in association with urban sprawl (Tan et al. 2010) – a question that deserves further study”.
This study was funded by the national Centre for Environmental Health, and U.S. Centres for Disease Control and Prevention. It was published in the Journal Environmental Health Perspectives and can be found here: http://ehp03.niehs.nih.gov/article/fetchArticle.action?articleURI=info%3Adoi%2F10.1289%2Fehp.0901879
By: Liz Staples
Student ID: 0725141
Animal manure has the potential of reducing net GHG emissions by up to 3.9%, says study. This, found in Environmental Research Letters, comes from the paper written by Amanda Cueller and Micheal Webber of the University of Texas titled “Cow power: the energy and emissions benefits of converting manure to biogas”. It states that by anaerobically digesting animal manure, which is the decomposition by bacteria into its basic elements, the biogas that results can be used to substitute a percentage of coal electricity used today.
In the United States alone, livestock produce over 1 billion tons of manure on a yearly basis. This manure is stored outside, left to decompose emitting foul odours and pollutants, contaminating water sources, and even emitting various greenhouse gases. When manure sits or is spread over fields, it releases methane and nitrous oxide which have an immense global warming potential then that compared to carbon dioxide.
In 2005 alone, the EPA (Environmental Protection Agency) reported that 7% of GHG emissions in the US were from the agricultural sector, equivalent to 536 million metric tons. And of this, up to 118 million metric tons came from sitting manure.
“Finding other approaches to manure management that decrease these emissions represents a valuable starting point for mitigating concerns about global climate change in the agricultural sector,” said Cueller, who goes on to say that biogases greatest potential is in replacing coal in electricity generation. Using two scenarios, Cueller compares the treatment of livestock manure. Scenario A, being ‘business as usual’: manure sits and coal is burned, and Scenario B, burning biogas produced from the manure to offset coal-fired power.
The MREC (Midwest rural energy council) of the University of Wisconsin-Madison estimates that one kW requires 5 to 8 dairy cows. Cueller, using various mathematical relationships and following the methods and results of scientific studies before, shows that when total livestock is taken into account, the energy possible from poultry biogas alone ranges from 9.2- 14.7 billion kWh annually, while dairy cows range from 6.8 to 10.8 billion kWh. As the United States consumes 3.8 trillion kWh annually, total biogas from all livestock can reduce up to 2.9% of this staggering amount.
But how does biogas really work? Combustion of the methane found in biogas, converts energy stored in the bonds of molecules into useable energy.
This combustion of methane results in a release of carbon dioxide into the atmosphere, however this output proves to be less then that which results from burning coal. Data comparing Scenario A and Scenario B show that net emissions of carbon dioxide can be reduced by up to 157.5 billion kg from the usage of biogas in Scenario B. Of course these values are affected by efficiency of the conversion, and the percentage of methane in the resulting biogas. With increased efficiency and methane percentages, carbon dioxide emissions decreased.
Scenario B effectively replaces two sources of Greenhouse gas emissions, manure and the burning of coal, with a more ‘friendly’ source, biogas.
Many farmers have begun to realize the efficiency of this renewable ‘poop-power’ as Mark St. Pierre, a farmer new to this method says, “One thing for sure we can count on is a constant supply of it.”
And while there seems to be nothing but good things coming from these operations, Cueller recognizes that the logistics of widespread biogas production must be determined at the local level before implementing such a plan. “Other issues such as best methods to process and distribute biogas should also be analyzed before biogas production and use are implemented in widespread fashion.” Cueller says that more research is needed to consider such an objective, but who knows maybe soon, the world will be run on this new ‘poop energy’.
Scientific Journal Article:
Dr. Michael E. Webber and Amanda D Cuellar. Cow Power: The Energy and Emissions Benefits of Converting Manure to Biogas. Environmental Research Letters, 3 034002 (pp), July 24, 2008. http://iopscience.iop.org/1748-9326/3/3/034002/fulltext
Other information found from:
Giant Hogweed Spreads!
There have been reported sightings of giant hogweed in residential areas. Hogweed is an invasive species of plant that can cause major harm to those who come in contact with it. If you get some of it’s clear liquid on your skin, it will cause a chemical reaction when exposed to UV light and cause your skin to blister and burn. The central fisheries board have also said that not only is this giant hogweed a threat to human health, but it is also a concern to streams and rivers.
This giant hogweed thrives along rivers and streams. Giant hogweed has a big canopy that blocks light from surrounding plants thus killing off the plants that hold the riverbanks together. Without these plants the banks of streams and rivers could erode away. The reason why giant hogweed spreads so quickly and in vast numbers is because when it comes time to produce seeds, all of the seeds from the plant just fall into the river or stream and are carried down great distances until they are washed ashore and more giant hogweed grows. Giant hogweed plants produce about 5000 seeds per plant so you can imagine the amount of hogweed plants are produced each year. Winter floods will brake apart the weak riverbanks and wash dirt into rivers and it has been shown (Gargan & Caffrey, 1991; Caf- frey, 1992) (E.I.F.A.C., 1974; Reiser & White, 1988) that this dirt will affect the spawning of fish in the area. This dirt build up in slow flowing parts of the river will create a perfect habitat for water plants to grow (Caffrey, 1990) and could potentially slow down the river or stream and may even block it completely, destroying many animal’s habitats.
Even though there is a lot of hogweed found along rivers and streams, there is also an abundance of hogweed along roadsides. This could pose a danger for people because you don’t feel pain when you first come into contact with hogweed, you just get a clear liquid on you and within ten minutes the chemical reaction will occur with the UV light and cause blistering. The fluid from hogweed can cause temporary and even permanent blindness if you get this fluid in your eyes. Small children are in danger because this plant is about as tall as a child and if, for example, they are playing in vacant lot, a stream, or a river, even under parental supervision they can come into contact with giant hogweed and get this clear liquid on them.
Scientists are studying giant hogweed very closely and trying to figure out how to stop it from spreading and eventually get rid of the invasive plant. They have decided to try and cut the plant down to the ground at different times of the year. Tiley & Philp found that when the giant hogweed is cut down in the end of June, they produce less seeds and therefore less new giant hogweed plants are produced. Other methods of controlling this giant invasive species have been tried, but are very expensive compared to just cutting down the giant hogweed. These other methods include various types of pesticides but the problem with these pesticides do not just kill the giant hogweed, the surrounding native plants are also killed. You can target big clusters of giant hogweed, but you can not get rid of all of it without killing other plants with these methods.
Authorities are asking residents to purchase a hogweed removal tool to cut down some of the giant hogweed in their local area. This tool is a blade on the end of a long pole so that the user can cut down the giant hogweed without getting any of the dangerous liquid on them. With the help of the community and the research done by these scientists we can eradicate this invasive giant hogweed.
Hydrobiologia 415: 223–228, 1999. J. M. Caffrey, P. R. F. Barrett, M. T. Ferreira, I.S. Moreira, K. J. Murphy & P. M. Wade (eds), Biology, Ecology and Management of Aquatic Plants. © 1999 Kluwer Academic Publishers. Printed in the Netherlands.
The most common method of processing biosolids is through carefully monitored composting. This method is very similar to decomposition of organic material in a natural system. A recent study done by the National Pingtung University of Science and Technology investigated the potential benefit of incorporating spent active clay in to biosolid composting. Spent active clay is a by-product of industrial food oil processing. “Unspent” active clay is employed for its ability to attract and affix impurities to itself when added to an oil. Once impurities are attached to the clay it is filtered out and the remaining oil is safe for the kitchen. Worldwide, 900 000 tons of spent active clay are left over from food oil processing every year.
Biosolids are usually composted with the addition of dry organic matter such as straw, rice husks or another readily available plant fiber. This method will temporarily affix heavy metals to some degree but once these compounds decompose fully the heavy metals will again be available for uptake. The aforementioned study investigated the incorporation of spent active clay into biosolid composting in order to affix toxic heavy metals into forms that will not be readily absorbed by plants or water. Unspent active clay has a negative electrical charge which causes its attractive properties. When spent active clay is added to a compost pile, small microbes will break down the residual impurities from its previous applications. Once these impurities are removed, the clay regains its attractive properties. This study has found that the reactivated clay will then attract and affix heavy metals, removing them from the agricultural process more effectively than other composting methods.
Active clay, also known as bentonite, is a naturally occurring group of compounds that are obtained for industrial purification processes through mining. Active clay deposits are a finite resource, making the reuse of active clay especially important.
The effect of incorporating active clay into biosolid composting was tested over a 15 week period. Biosolids, rice husk and spent active clay were mixed at an initial ratio of three parts biosolids to one part each of rice husk and spent active clay. The biosolids were treated with lime to neutralize the acidifying properties of the spent active clay. These constituents were mixed homogenously and left to decompose with occasional turning. Throughout this process the total content of heavy metals, organic carbon, nitrogen, and phosphorus was tested at regular intervals. After fifteen weeks of composting, the resultant product was found to have a desirable ratio of carbon to nitrogen. This ratio is considered the major indicator of compost maturity. As well, the heavy metals present in the final product were found to be in compounds unlikely to be taken up by a plant’s roots or washed into the water supply.
This recent study suggests that the incorporation of spent active clay into large scale composting of biosolids is an important step that can greatly increase the safety of the final products. Further, it has the additional benefit of making maximum use of active clay, a finite resource. Unfortunately it is impossible to destroy heavy metals, however it is possible to affix them in unreactive compounds which are not likely to be inadvertently absorbed into a living body. The application of spent active clay, previously considered a waste material, has been shown to be effective in creating these safer compounds. It is through this type of important research that our uniquely human way of living becomes closer to one that we can continue without significant degradation of nature.
C.P. Ho, S.T. Yuan, S.H. Jien, Z.Y. Hseu. 2010. Elucidating the process of co-composting of biosolids and spent active clay. Bioresource Technology, 101: 8280-8286.
By Dylan Harding
Urbanization is a familiar concept and in its most basic form urbanization is the congregation of a large number of people into one community. With urbanization comes the need for artificial lighting such as street lights and large stadium lights used to light up the field at a sporting event. These artificial lights cause anthropogenic light pollution (light pollution caused by humans). Organisms living in an ecosystem near to an urban area will inevitably come into contact with these artificial lights and these lights could potentially have an effect on these organisms. A study performed by Bart Kempenaers and his colleagues at the Max Planck Institute for Ornithology aimed to test the effects of these artificial lights on the dawn song of five song birds which yielded some pretty interesting results.
The study was performed by comparing three separate territories each of which contained the five species of songbirds. These territories included an edge territory (which is a territory on the edge of the urban interface) with no artificial light, an edge territory with artificial light (street lights) and a central territory (which is a natural territory in a forest away from the urban interface) with no artificial light. Of the five species of songbirds the males of four of these species near street lights began singing much earlier in the day as opposed to the males in other territories. This observation of the males near the street lights singing earlier was much more apparent in the species of songbird that naturally prefer to sing earlier at dawn. The blue tit songbird was the species the study primarily focused on. The breeding habits of the blue tit songbird were compared between both edge territories containing and not containing artificial light and the central territories. This study would take place over the span of seven years.
After seven years of study a number of surprising results would be observed. The female blue tit songbirds who resided within the territory with street lights laid there eggs an average of one and a half days prior to species residing within other territories without the influence of street lights. Male blue tit songbirds living in an edge territory containing street lights had double the success of acquiring an extra-pair mate as opposed to other male blue tits living in edge territories without lights and in the central territories. This means that those males living near street lights were able to mate with more than one female allowing those males to be better able to spread their genes amongst the population. The males living near the street lights also started singing much earlier in the day and were observed to have doubled the success of acquiring an extra-pair mate. All of these factors put together leads to the observation that males living near street lights had greater reproductive success as opposed to those males living in other territories where there were no street lights. Since more females were breeding with the males living in territories where artificial light existed it implied that females were more attracted to the males who began singing earlier in the day.
So a false sense of quality has been placed in the minds of the female birds living near the territory with the street lights. It has been observed that females prefer those males who sang earlier in the day. This observation can be used to show that artificial light has an effect on the breeding habits of the blue tit songbird by creating a quality-indicator trait within the female’s mind. This trait is that a male who starts to sing earlier in the day is of higher quality and that they must in turn be more suitable as a mate. It is still unclear as to whether or not artificial lighting will have a negative impact on the species due to females mating with males they would not otherwise mate with but it can be concluded that artificial lighting has an impact on the breeding habits of blue tit songbirds. The fact that males who sing earlier in the morning are more likely to find a mate alludes to the classical phrase “the early bird gets the worm” or in the case of the blue tit songbird “the early male gets the female.”
Bart Kempenaers, Pernilla Borgstrom, Peter Loes, Emmi Schlicht and Mihai Valcu (2010). Artificial Night Lighting Affects Dawn Song, Extra-Pair Siring Success, and Lay Date in Songbirds. Volume 20, Issue 19, 1735-1739. http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VRT-511J7V4-3&_user=1067211&_coverDate=10%2F12%2F2010&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_acct=C000051237&_version=1&_urlVersion=0&_userid=1067211&md5=7073a8c754b1dec9723bf28275e3b58b&searchtype=a