Focus on Biogeochemical Cycles: Challenges and Solutions
Have you ever wondered where the food that you consume, the fresh water that you drink, or the air that you breathe comes from? What is the history behind the essential inputs of our lives and what can we do to better manage them?
Over geological time and evolutionary history, the interplay between different organisms and the physical makeup of the natural world has resulted in the emergence of relatively stable patterns of nutrient and chemical flows. Food webs, for instance, describe how energy and nutrients flow through the various organisms that make up an ecosystem. Each organism’s life cycle plays out within a network of relationships with both predators and prey. Biogeochemical cycles refer to how important chemical elements cycle through the ecosphere, connecting all of life and the physical substrate within which they live. Examples of important biogeochemical cycles include the carbon cycle, the nitrogen cycle, the phosphorus cycle, the oxygen cycle, and the water cycle. These cycles underlie the welfare of all life on earth.
Human activity has disrupted and impacted the natural flows of chemicals and nutrients in our environment in many different ways. Unfortunately our disruption of ecological cycles has had negative consequences for the wellbeing of humans as well as other life forms.
In this Discussion you will describe a biogeochemical cycle or nutrient flow of your choice, explain how human activity has impacted the cycle, describe one or more problems caused by our impact, and reflect on what we might do to improve or mitigate our impact.
To prepare for this Discussion
Review the Interactive Unit for this week and the links posted by your professor, and then conduct your own independent research to support your post.
Select a particular nutrient flow or biogeochemical cycle to focus on in your primary research-based post this week. Consider some of the benefits or services provided by this natural flow or cycle.
Consider the ways that humans impact the cycle of flow of your choice and how this impact challenges the health of humans and other life forms.
Reflect on what can be done to improve or mitigate our impact either individually or as a society.
With these thoughts in mind, complete the following:
Spark Response Post (20 points):
By Day 2
Post a two or more paragraph response to the Discussion Spark posted by your professor on Monday (Day 1) in the week 2 discussion forum. Notice that the responses to the Discussion Spark, the primary research-based Discussion Topic, and your colleagues or professor will be graded together. SPARK POST: This week your primary research-based discussion focuses on understanding how chemicals and nutrients critical to the life cycle flow through the atmosphere, geosphere, and biosphere, and how humans impact and manage these flows. In the spark this week you’ll consider some of the ways that humans pollute the air.
How are some ways that you or your neighbors pollute the air? What are some things that you can do as an individual to decrease air pollution?
Primary Research-based Post (35 points):
By Day 4
Post: four or more paragraphs in which you:
briefly describe a biogeochemical cycle or nutrient flow of your choice,
explain at least one way that humans impact this flow and why this is important to the health of humans or other life forms; and
reflect on at least one measure to improve our impact (either as individuals or as a society). If other people have already presented substantive posts on a given cycle, you might consider treating a different cycle. Cite at least two authoritative reference sources beyond the Interactive Unit for this week to support your presentation in this post.
Read a selection of your colleagues' and professor’s postings
The atmosphere has a mixture of gases, including nitrogen, oxygen, and inert gases. Oxygen is the second most abundant gas after nitrogen and can be found freely in the air or dissolved in water. Oxygen is critical in various processes, for instance, respiration, and is typically combined with other elements to form biomolecules, for instance, nucleic acids and proteins.
The oxygen cycle as a biogeochemical process describes oxygen movement within the ecosystem, the lithosphere, and the atmosphere. During the cycle, the green plants release oxygen into the atmosphere through photosynthesis; respiring organisms utilize the released oxygen; and lastly, the former release carbon dioxide into the atmosphere that is used by plants during photosynthesis, and the oxygen cycle begins again.
In most third world countries, individuals typically practice overgrazing; exposure of plants to excessive grazing for a longer time, for instance, to meet the intended profit margin. Additionally, in certain countries, the more animals an individual has, the more wealthy a person is considered. Overgrazing usually results in a negative impact on the ecosystem balance, mostly on the oxygen cycle. The overstocked animals feed on too many plants more than they(plants) are growing; this results in a shortage of plants that would have to take in the animals' released oxygen to create oxygen balance.
The activity also, increases the atmospheric carbon dioxide concentration. Consequently, this effect raises the global warming level resulting in an abnormal increase of the earth’s mean temperatures that, in the long run, results in increased drier conditions and thus desertification.
Overgrazing can be curbed through proper land and animal management; it entails keeping the appropriate number of animals in a piece of land, for instance, as required by the state’s policies. The practice can be controlled by adopting the appropriate grazing methods, such as rotational grazing, to give substantial time for the plants in the previously grazed land to grow and thus maintain the oxygen cycle.