Climate-Smart Agriculture and Biophysical Consequences in the Midwest

by Ali Siddiqui

Climate-smart agricultural techniques are agronomical practices that help alleviate the consequences that climate change has on agriculture. Agronomical practices are related to soil management and production of field crops. Currently, in the Midwestern US different climate-smart techniques have been advocated in order to increase crop production. These include utilizing different crop cultivars in order to reap the benefits of earlier planting dates and a longer growing season and no-till agriculture in order to reduce soil emissions and maintain soil moisture. Bagley, Miller, and Bernacchi (2015) using observational data and an agroecosystem model that uses future temperature and CO2 concentrations determine the effectiveness of climate-smart techniques and their biophysical impacts. Continue reading

Environmental Costs of High-Density Cattle Farming

by Sarah Whitney

A dramatic increase in the density of United State’s dairy farms has created a cause for concern across the nation. The number of cattle per farm has jumped from 1000 to more than 15,000 cows. Dairy producers are easily able to increase their production and thus their profit with access to cheap fuel and feed. The State Department of Natural Resources states that dairy farms containing 500 cows or more have increased by 150% in size, but the number of dairy farms in the United States has decreased by a third. Such an increase in high-density cattle farms has generated a major issue with proper manure disposal. On small-scale farms, roaming cows naturally fertilize the pasture with their manure. Yet on large-scale cattle farms, where cows are confined to a barn, the ratio between cattle and land is extremely out of proportion and thus the significant amount of manure in a small space poses a huge environmental problem. Continue reading

Seasonal Energy Storage using Bioenergy Production from Abandoned Croplands

by Christina Whalen

Producing electricity from biomass could potentially provide a back-up storage source for the intermittency that accompanies wind and solar energy production. Biomass electricity also provides a carbon-negative and efficient method for bioenergy production, which is important because of mandated restrictions on carbon emissions. Furthermore, biomass electricity also provides an efficient method for providing renewable transportation energy that could replace current liquid fuel approaches. Although bioenergy may be important in producing electricity and developing energy storage mechanisms, the economic and environmental effects are unclear. Studies have been conducted on abandoned agricultural lands to try to find a path of producing bioenergy that has reduced land impact. Campbell et al. estimate at county level, the magnitude and distribution of abandoned agricultural lands in the United States and attempt to quantify how much potential energy storage could be produced by the provided bioenergy. Continue reading

Cellulosic Ethanol Technically Comes of Age

by Emil Morhardt

Making liquid fuel out of crop waste is, in principal, an extremely good idea. But the ethyl alcohol (ethanol) we add to gasoline—and also drink in vodka, wine and beer—has been made out of edible fruits and grains. Corn ethanol, the main gasoline substitute is made out of the corn kernels which otherwise might become corn meal or tortillas, cutting into the food supply and encouraging conversion of more land into cropland. There have been many studies on the effect of this land conversion on atmospheric CO2 levels, and it appears that it will often be a decade or more before the CO2 released from land conversion will be offset by the substitution of ethanol for fossil fuels. Continue reading

Oil Palm Plantation Boom in Indonesia

by Chieh-Hsin Chen

The anticipated depletion of fossil fuel has caused the production of alternative fuel sources to become an extremely important field of industry. Many less developed countries in South East Asia promote mass production of biofuel crops as a primary export. Palm oil, used in cooking as well as biofuel, is one of the main exports from Indonesia. The high demand of palm oil has led to a rapid increase of oil palm plantations, leading also to massive deforestation. Riau Province is one of the largest oil palm producing regions. From 1990s to 2012, there has been a significant decrease of forest in the region due to the boom of oil palm plantations. Ramdani and Hino (2013) analyze satellite imagery and greenhouse gas emissions from different time periods to determine the scale of deforestation. The results show that in the Riau Province, the oil palm industry rapidly increased from 1990 to 2000, with transformation of tropical forest and peat land as the primary source of emissions. Continue reading

Life Cycle Inventory of Electricity Cogeneration from Bagasse in the South African Sugar Industry

by Monkgogi Bonolo Otohogile

South Africa’s sugar industry is worth over $1.11 billion and South Africa is consistently ranked as one of the top 15 sugar producing countries in the world. The sugar manufacturing process also produces thousands of tonnes of a biomass called bagasse that is being underutilized. Mashoko et al. (2013) investigated the potential for the cogeneration of steam and electricity using bagasse in South Africa’s sugar industry. The authors’ developed life cycle inventories for bagasse electricity production, which they used to evaluate the environmental impacts of cogeneration. Using data supplied by various affiliated organizations and studies, Mashoko and colleagues determined the greenhouse gases, energy ratio, non-renewable energy input, sulfur dioxide, and nitrogen dioxide of a functional unit of 1 GWh of bagasse-derived electricity produced in the South African sugar industry and compared it to coal-derived electricity and bagasse-derived electricity in Mauritius. The authors found that bagasse-derived electricity performed better than coal-derived electricity in every category outlined above. Mashoko et al. argued that by increasing their boiler pressure, the sugar industry could produce cleaner electricity during the sugar life cycle by following in the footsteps of Mauritius. Bagasse-derived electricity could mitigate South Africa’s massive carbon dioxide emissions while also making the sugar industry self-sufficient and contributing to the grid. Continue reading

Sustainable Bioenergy: Evolving Stakeholder Interests

by Christina Whalen

The diversity of stakeholders’ interest and values complicates the decision-making process involved in the future of sustainable bioenergy production. Johnson et al. explores the different stakeholder perspectives and then examines how this diversity affects research on the subject. Biofuel production has been brought to the public’s attention because of the need to mitigate greenhouse gas (GHG) emissions, increase energy security, support farm production, and improve economic growth in rural areas. The recent increase in biofuel consumption has resulted in stakeholders questioning environmental, economic, and social benefits of using agriculture to produce ethanol and biodiesel. As a result, policy makers have passed legislation and modified regulations about renewable fuel production in order to promote the use of alternative biomass feedstocks. The general research community is looking for ways to convert this feedstock to a usable fuel source in vehicles. The expansion of biofuel production coincides with Continue reading

Global Effects of Biofuel Expansion

by Chieh-Hsin Chen

According to various economic and environmental estimations, it is highly possible that future global energy demand will increase up to 250% by 2050, which will be impossible to achieve using current available natural fuel sources. Biofuels have been proposed as a potential low-carbon energy source that may help assist in meeting energy demands; as well as improving greenhouse gas emission problem from fossil fuel combustion. Hallgren et al. (2013) used various assessment models that link an economic model with climate, biogeochemistry, and biogeophysics models to examine the effects of possible land use changes from an expanded biofuel program over the first half of 21st century. Surprisingly, the results of this modeling effort show that overall, the biogeochemical and biogeophysical impacts are negligible from a global perspective; the models do show regional patterns of climate change in certain areas such as Amazon Basin and parts of Congo Basin. Considering the amount of land conversion that will be needed there will no doubt follow considerable debate about the accuracy of this conclusion. We would welcome your comments below, but more explanation follows. Continue reading