Units 1 and 2 Flashcards
What is the Scientific Method?
The process of objectively establishing facts through testing and experimentation.
What are the steps of the Scientific Method?
- Recognize a problem
- Develop a hypothesis
- Design and perform experiments
- Analyze and interpret data
- Share the knowledge with other scientists
How is sustainable development applied to the effective management of a resource?
Sustainable development includes environmentally sound, economically viable and socially equitable decisions when developing and implementing public policies and programs. These steps are important in ensuring that future generations will have access to the resources we use today.
What are general features & conclusions that can be made when biocapacity and ecological footprint are compared over time and between nations?
We can determine if we run the risk of exceeding the ability for the environment to sustain itself.
What are the 3 types of resources? Explain
- Perpetual resource is a resource that will always be available.
- Renewable resource should ideally always be available as long as it’s not over-exploited and allowed to regenerate.
- Non-renewable resource is depleted upon consumption.
Give examples for each type of resource.
- A perpetual resource is wind or sunlight.
- A renewable resource would be trees, fresh water or fish.
- A non-renewable resource is fossil fuels (coal, natural gas, oil) or minerals (aluminum/copper)
Define the term sustainable development and how this is applied to the effective management of a resource.
Includes 3 pillars that should be weighed equally; the needs of society and human wellbeing, economic evaluation and context of the environmental limitations and constraints. This should be applied to effectively manage a resource to meet the current needs of our population and to ensure it’s usability for future generations.
Why is a person living in a less populated developed nation said to have a larger impact on the environment than a person living in a highly populated, less developed nation?
One individual in a highly developed nation consumes more resources than that of an individual in less developed nation.
In a highly developed nation there are people buying and throwing away items (like cars, phones, appliances etc..) whether or not they’re broken, all the time. In a less developed nation, although population may be higher, resources consumed are more for survival instead of affluence.
Explain how negative and positive feedback function to affect and moderate the environmental processes such as population growth and carbon dioxide concentrations in the atmosphere.
Negative feedback is when input and output cancel each other out, stabilizing the ecosystem or environment. Positive feedback is when the output feeds back into the system and continues further in one direction.
What are examples for positive and negative feedback?
An example for positive feedback would be exponential growth in the human population or CO2 emissions and climate change. An example of negative feedback would be if you were to remove vegetation by the shore to see the water better, but in doing so, you remove the stability of the soil. You then might see soil erosion and loss of land. Negative feedback would be replanting vegetation to prevent further erosion and restabilizing the shore.
What is a food chain? How is it structured?
A food chain is a hierarchy of food dependence and it’s structured to look like a pyramid. Within the pyramid there are different levels of the hierarchy that are called trophic levels. The first tropic level is producers, followed by primary consumers in the secondary trophic level. The third level is secondary consumers and the fourth is tertiary consumers.
Give examples of what may be on each trophic level.
- Producers - plants (algae)
- Primary consumers - herbivores (caterpillars/ hummingbirds)
- Secondary consumers - omnivores/carnivores (snakes/humans)
- Tertiary consumers - carnivores (sharks/hawks)
What laws govern the flow of energy in ecosystems?
There are two laws of thermodynamics, first law states that energy cannot be created nor destroyed, but it can be transformed. The second law states that transformations are inefficient and as energy moves from one form to another, there is tremendous loss that isn’t directed to useful work.
Which trophic level do decomposers belong to?
ALL OF THEM! Decomposers (like bacteria and fungi) consume waste and dead organisms to obtain residual amounts of stored energy.
What evidence is there proving that the laws of thermodynamics exist in the ecosystem?
There is evidence of these laws because of the amount of individuals at each tropic level. We see that at the first tropic level there is an abundance of plants because there needs to be a way to capture energy. As we go up in trophic level, the amount of individuals reduces, this happens because transforming energy is inefficient. Plants can capture the energy but most of it won’t be passed to the consumer.
What is an ecosystem? How do you define its boundaries?
An ecosystem is a community of biotic organisms living in conjunction with the abiotic organisms in their environment, interacting as a system. The boundaries of an ecosystem can be defined as the transition area between two biotic communities.
Identify a highly productive aquatic ecosystems; one that isn’t very productive. Why is there such extremes in production across ecosystems?
A highly productive aquatic ecosystem is the coral reef. There’s lots of biodiversity, algal and seagrass beds. The open ocean is not a productive ecosystem.
The reason why there is such a difference in productivity for these two ecosystems is because the ocean has low nutrient levels. Producers need nutrients to grow and multiply, coral reefs receive these nutrients through run off from the land.
What is the effect of the second law of thermodynamics on pyramids of energy and biomass?
As energy transforms from one form to another there is a tremendous loss that is not directed to useful work. This creates the pyramid shape as there are more producers than consumers.
Humans have profoundly influenced the nitrogen cycle through what pathway?
By increasing the amount of nitrogen stored in the biosphere through the burning of fossil fuels, this can result in a decline of biodiversity.
Humans have profoundly influenced the phosphorus cycle through what pathway?
When humans use fertilizer that has an abundance of vital nutrients, like phosphorus, and it rains. That may cause run off where the nutrients find themselves in bodies of water. With the excess of phosphorous and the movement from the lithosphere to the hydrosphere we can see a massive loss of biodiversity in these areas.
Humans have profoundly influenced the carbon cycle through what pathway?
One of the ways people have impacted the carbon cycle is through deforestation. When a large forest is cleared the stored carbon is then released into the atmosphere. When we have an excess of carbon we see an increase in global temperatures and ocean acidification.
Describe the steps involved in the transformation of carbon from carbon dioxide found in the atmosphere to carbonates found in oceanic sediments.
Through the carbon exchange, we have carbon dioxide in the atmosphere that is transferred to the ocean. Once the carbon is in the hydrosphere, marine life will use the carbon and transform it into calcium carbonates.
Describe the steps involved in the transformation of carbon in carbon dioxide in the atmosphere to glucose in the hydrosphere.
Aquatic plants take in carbon dioxide from the atmosphere through a process called photosynthesis which then produces glucose.
Molecular nitrogen gas (N2) is the most abundant component of our atmosphere making up 78%. Why then is it a limiting factor to plants and we must add it to fertilizer?
Nitrogen gas is unusable as is since it has to be broken down by other organisms first because of this, there is a limited amount of usable nitrogen in the soil.
What makes the phosphorus cycle so very different to the nitrogen cycle? How is the P cycle similar to the carbon cycle?
The biggest difference between the nitrogen and phosphorous cycle is that phosphorus is not present in the atmosphere. They are similar because they both interact with the soil and water components of our ecosystem.
Provide examples of the types of interactions found between species with outcomes that could be described as beneficial to both; beneficial to one yet not harmful to the second; and beneficial to one and harmful and/or deadly to the other.
- Mutualism (beneficial to both) - bees and nectar
- Commensalism (beneficial to one, the other is unaffected) - moss residing on a tree
- Parasitism (beneficial to one, harms the other) - ticks living on the surface of an individual
Describe the steps of the nitrogen cycle.
- Nitrogen fixation
- Nitrification
- Assimilation
- Ammonification
- Denitrification
