Ecosystems, Biomes, and Cycles Flashcards

Ecosystems and Environments

An ecosystem is the interaction of living (biotic) and non-living (abiotic) things in a specific region.
The environment refers to the entire natural world;
An ecosystem is a specific portion of the world's environment.
A habitat refers to the environmental conditions a species needs to survive. For example, the Arctic is a suitable habitat for caribou but not for capybaras.

Organisms can have various relationships with each other.
- Competitors: Organisms that fight over a shared resource.
- Symbionts: Organisms living in a close relationship with each other.

Symbiosis: Any organisms that live in close proximity to each other.
- Example: A tapeworm in a human is symbiosis, as the tapeworm lives in close proximity to the human, but it is not beneficial to the human.
Mutualism: A relationship that benefits both species.
- Examples:
  - Bees and the plants they pollinate.
  - Coral reefs, which consist of photosynthetic algae and coral-building animals (polyps).

The key question to ask in all species interactions is whether one, both, or neither species benefits from the relationship.

A biome is a region on Earth that shares a consistent yearly average temperature and precipitation pattern.
- Examples: Tropical rainforest and tundra.
Biomes are determined by average temperature and precipitation patterns.
Other characteristics, such as vegetation and animal diversity, are secondary and result from temperature and precipitation.
If temperature and precipitation patterns change, biome locations can shift.
Currently, there is an expansion of the tropics away from the Equator as global temperatures rise.

Aquatic biomes are influenced by temperature and precipitation, as well as:
- Salinity (saltiness level)
- Flow
- Depth

The salinity level of an aquatic biome is important because the plants and animals that live there need to be adapted to the dehydrating effects of salt.
- Trees like mangroves have adaptations to pump salt out of their leaves.

The flow of an aquatic biome is important because:
- It disrupts the surface, allowing oxygen to diffuse into the water.
- It carries sediments and nutrients from one place to another.

Estuaries are where the mouth of a river empties out into the ocean.
They have a unique salinity level, often referred to as brackish (partially saltwater, partially fresh).
Species in estuaries, like mangroves and saltgrasses, are uniquely adapted to these salinity levels.
Estuaries are highly productive due to the large amount of sediments and nutrients transported by the river, which supports high plant and animal biodiversity.

Biomes are determined by average annual temperature and precipitation.
Organisms living in biomes are uniquely adapted to those temperature and precipitation patterns.

Law of Conservation of Matter: Matter is never created or destroyed; it only changes forms.
Focus: How carbon, nitrogen, phosphorus, and water cycle throughout ecosystems.

Sources of carbon return carbon to the atmosphere.
Carbon sinks take carbon out of the atmosphere.
The amount of time carbon spends in its reservoirs varies and is important to global climate.
The atmosphere is a critical carbon reservoir because the amount of carbon it stores determines Earth's global climate.
- More carbon dioxide and methane in the atmosphere lead to a warmer Earth.
When studying the carbon cycle, it's important to consider whether carbon is being taken out of or put into the atmosphere.
- Photosynthesis is a key step.