Unit 7 Blog

Forestry Discussion

In many ecosystems, forest fires are an important natural process.  In recent years it has become more commonplace for prescribed burns to be used as an alternative way to manage forests.  Discuss at least one benefit and one cost for managing forests in this manner.  Make sure that for each example given, you discuss the economic, ecological and human impact of your example.

One benefit is that the risk of uncontrolled fires is minimized. Forest fires are natural process that occur as a result of lightning and lots of dry organic matter piling up to return nutrients trapped in organic matter to the soil. Uncontrolled, they can be very dangerous to human settlements and endanger people since they spread so fast. It would be an economic burden because of all the lost businesses and the costs of repairing damaged settlements. Uncontrolled fires may also spread across vast expanses of land and further endanger already endangered species. Controlled fires minimize the risk of uncontrolled burning by managing the amount of tinder available. 

One cost quite literally is that controlled fires do require a lot of equipment and labor to effectively manage. The tools to set and manage the fire can be quite costly economically. Firefighters can be injured while trying to control the fire, and plants die as a result of the fire, as well. 

Global Nutrition Discussion

While meat is a regular part of most American's diets, many people in other parts of the world have a primarily plant-based diet because meat is very expensive.  Explain why meat production is more costly than grain production in terms of the amount of land required, the amount of energy and resources needed and the overall environmental impact of meat production.

Meat production requires more land because not only is the land that houses the animals being raised for animals necessary, but land is required to grow the plants necessary to sustain those animals, which is more land per calorie than if just the plants were raised for human consumption. The transfer of energy is also less efficient since there are more trophic levels involved; only about 10% of energy gets passed on from each trophic level, so humans are getting about a tenth of the energy from meat as they would from the same mass of plants. In both cases, plants need to be planted and processed, but meat production has the additional costs for raising and processing the animals which results in external land, resource, and energy costs. 

Genetic Engineering Discussion

Genetically modified crops have become increasingly popular in the industrialized world.  Describe the benefits and costs of farming GM crops versus non-GM crops in terms of their environmental and economic impacts.  Make sure you discuss one at least one benefit and one cost for each impact.

Genetically modified crops often have increased yield and are resistant to certain herbicides and pests which is economically favorable since increased yield can be sold for more profit and less money can be spent on pesticides. Being able to spray herbicides indiscriminately across the field decreases labor costs and also decreases the need for tilling, which decreases the oxidation of soil that results in increased carbon dioxide being released, as well as minimizes erosion, which helps soil quality. 

GMOs, though, are stigmatized as their effects aren't completely known since they are relatively new which can cause them to sell worse in the marketplace and decrease profit. They can also cause a decrease in biodiversity because they are so hardy and crowd out native species, just like invasive species do in the status quo. A decrease in biodiversity could have drastic impacts since it is key to ecological resiliency and sustainability.

Sustainable Agriculture Discussion

The dust bowl of the 1930's was caused by a combination of extended severe drought conditions in the midwest and poor farming practices.  Not sure what the dust bowl was???  Take a look at this 3 minute video to help you get a better idea of the utter devastation that took place!  Http://www.history.com/topics/dust-bowl/videos/black-blizzard

In an effort to avoid a second dust bowl, soil conservation has become a priority to many farmers.  Discuss at lease two examples of farming techniques that can be used to prevent soil erosion and improve soil quality.  For each example, discuss both the economic and environmental benefits of these techniques.  

No-tilling agricultural technique can help minimize erosion. Tilling involves turning soil upside down to kill pupae and weeds, but this breaks apart soil particles and makes them more susceptible to erosion. It also increases the exposure of more soil which results in the oxidation of organic matter deep in the soil which reduces the organic matter content of the soil and increases atmospheric carbon dioxide concentrations. While no till agriculture minimizes these negative effects, it also requires increased herbicide use which can runoff and cause eutrophication and other problems in other places. 

Intercropping can help minimize the nutrient depletion of soil by planting two crops that have different needs that are complimentary to the other. For example, corn can be planted with peas since corn requires a lot of nitrogen and peas are nitrogen fixing; this would replenish nitrogen in the soil and minimize degradation. Farmers would no longer need to let the land lie fallow to regain nutrients and forgo profiting from the land that year which is economically beneficial. Farm machinery, however, is specific to one crop so it could be costly to either invest in the labor or new machinery necessary to harvest both crops concurrently. 

Pest Management Discussion

Many farms have started using integrated pest management as an alternative to traditional pesticides.  Define IPM and give at least two examples of of how it works.  For each example, explain how this method of pest control is considered to be more environmentally friendly to farms than traditional pesticide use.  Additionally discuss whether or not the method is considered to be more cost effective than traditional pesticides. 

Integrated pest management aims to minimize pesticide usage by using many different techniques, such as crop rotation, intercropping, pest-resistant crop varieties, enticing predators of pests, and limiting use of pesticides. 

Crop rotation thwarts pests that feed on specific crops that may have eggs in the soil from increasing in population size by switching up crops and eliminating their food source every year. This also minimizes the spread of crop-specific infections that may lay latent in infected plant material in the soil. Additional machinery may be needed to manage the second crop since agricultural machinery is so specialized which is costly but these costs should be offset by the decreased need for pesticides (since pests have no food source and can't survive) which must be purchased repeatedly and are quite costly themselves.

Pest-resistant crop varieties are often genetically engineered and minimize the need for pesticide application by producing their own organic version of pesticide to ward off pests. This can minimize pesticide runoff as well. Genetically modified organisms are patented, though, so new seed must be purchased every year. The cost of purchasing new seeds every year can still be offset by the increased yield and decreased purchase of pesticides, though.

BIG Picture Discussion  

This is where you will make the four BIG PICTURE connections to the ENTIRE UNIT (forgot what these were over the holiday???  human impact, environmental impact, economic impact and legislation that applies to the unit). Please tie in information you learned in your reading (chapters 10 and 11), from completing your assignments, the documentary we watched and from your labs.  There is not an exact length that I am expecting other than it should definitely be at least a paragraph for each section, should be thorough and show understanding of the topic.  Remember to be specific in your examples.  Do not just say "there are laws that govern this" or "people destroy the Earth."  Give me the names of the laws, what they regulate and who enforces them.  Tell me what humans are doing to destroy the earth. 

Human Impact: Humans have had a huge impact on the environment which is why land management is needed. Urban sprawl is a result of an increase in desire for suburban life and has resulted in the disruption of ecosystems and other natural resources as human settlement has expanded. This, in turn, negatively affected the new towns, especially in terms of water supply and available land, so there was a push towards sustainable forms of development that have been much less harmful to indigenous ecosystems but still have an impact. Agriculture is an entirely human process that has disrupted large swaths of land all around the world. Humans have clear cut large portions of land to grow their own crop which led to overworked soil and increased erosion. To combat these negative effects that made it hard to farm, humans developed alternate styles of farming such as intercropping and crop rotation, as well as GMOs that could withstand hardier conditions. GMOs are one of the biggest human impacts because humans engineered seeds to meet their benefits; these GMOs can have detrimental effects on ecosystems by acting as invasive species, though, and their total effects on agriculture and people are as yet unknown since they are relatively new.

Environmental Impact: Agriculture has had many effects on the environment. Obviously, in order for humans to cultivate crops, they have had to clear cut large areas of land to raise their desired crops. This results in many entire ecosystems being lost which is detrimental to biodiversity. GMOs have also been known to further crowd out native species which also harms biodiversity. Reduction in biodiversity is a critical problem because biodiversity is key to an ecosystem's resiliency and resistance as it preserves many adaptations that can be useful depending on what changes occur. Because so much land has already been poorly managed and so many ecosystems have been lost, public lands have been set aside which preserve natural ecosystems and maintain biodiversity. 

Economic Impact: Lost biodiversity means lost ecosystem services which always has an economic cost even if not entirely quantifiable. GMOs have also been shown to crowd out small farmers and their techniques because they keep getting outsold by these large corporations who have larger yield. As a result, more and more farmers are being contracted with large agricultural firms, leading to large business conglomerates and monopolies and fewer independent small farmers who can use their own methods. This allows large corporations to have a monopoly. GMOs have also increased yield and decreased pesticide usage which yields greater profits for the farmers. The increased need for herbicides and need to rebuy seeds each year can offset that greater profit with greater costs, though.

Government Legislation: There are multiple laws concerning land management. Public lands have various restrictions on what may or may not be done there, enforced by the National Park Service or the Bureau of Land Management depending on the type of public land. The US Fish and Wildlife Service has multiple laws concerning acceptable fishing to prevent overfishing and the tragedy of the commons. The Federal Insecticide, Fungicide, and Rodenticide Act (FIRFA) allows the Environmental Protection Agency (EPA) to regulate chemicals used to kill of pests, especially in farming. The Clean Water Act has a similar provision and is also enforced by the EPA.