Introduction to Ecology and Biomes

Housekeeping and Exam Reviews

The instructor worked hard last week to accommodate those wanting to review for Exam 3 due to a busy schedule this week.
If you missed the opportunity to review, the instructor sincerely apologizes.
He stayed late on a couple of nights to ensure all students had the chance to be taken care of in preparation for the upcoming final exam.

For students looking to identify specific chapters or topics to focus on for final exam preparation, the instructor is open to helping with that.
A general rule of thumb: If a student scores around the class average, it’s unlikely they did poorly in a specific chapter. Their self-assessment regarding their comfort with the material is important.
If a student did poorly overall on Exam 3, it indicates issues across multiple chapters, and reviewing specific questions may not provide clarity. Those specifics can be dealt with during the last week of classes.

A full review session is scheduled for Thursday before the final exam.
The last day of lecture will involve a review session, covering material not included in the lab practical.
This will allow for targeted discussion of topics that students wish to revisit, with the instructor prepared to show a bank of questions based on various topics throughout the semester.
Deadlines for filing for exam changes, potentially missed due to timing, have likely passed.
It is essential for students facing multiple finals to check the deadlines for adjustments through the Dean's office.
It is emphasized that these changes do not reflect changes in the Registrar system, all adjustments must go through the Dean's office.

Secession: The instructor defined succession as a process of recovery after a disturbance but also a means of ecosystem construction over time:
- Succession starts with bare rock and moves towards complexity over time.
- The weathering of rock allows for the slow accumulation of soil and nutrients, starting small with algae or mosses and progressing to larger plants.
- As plants die and decompose, they add organic material to the soil, enriching it and allowing for a wider variety of organisms to inhabit the area.
- Eventually, ecosystems can develop into complex structures like rainforests or coral reefs, marking what is known as a climax community.
Examples of disturbances include:
- Mild events such as branches falling or seasonal changes.
- More severe disturbances include wildfires.
Succession is a reset process for ecosystems, aimed at returning to an established ecological balance.

Biome: Described as a global set of conditions that support various ecosystems primarily defined by climatic factors.
- Mainly characterized by the plant life that exists in these regions, which is influenced by sunlight, precipitation, and temperature.
- Different conditions in various regions create distinct types of biomes.

Main factors shaping climate and therefore biomes include:
- Total amount of solar radiation.
- Sunlight and precipitation levels which define whether particular types of flora can survive (e.g., oak trees require longer growing seasons).

The Earth is tilted approximately 23.5 degrees, affecting solar radiation reception and resultant climate.
- Differential heating of the Earth's surfaces creates wind, ocean currents, and precipitation patterns, resulting in varying local climates.

The tilting of the Earth contributes to seasonal change (e.g., warmer summers, colder winters).

Differences in density and temperature allow for the movement of air masses, forming continuous cycles.
These air movements impact precipitation levels (wet and dry areas).

The movement of the Earth’s surface underneath air masses creates deviations from apparent wind direction, critical for understanding weather patterns.

The movement of warm and cold waters influences temperatures in nearby landmasses.
Gyres: Major ocean currents that encapsulate water and can gather plastic debris (e.g., ocean garbage patches).

Warming and moist air moving over mountains cools and condenses upon rising.
The air loses moisture on one side (windward side), resulting in lush vegetation, while the leeward side becomes arid (rain shadow).

Biomes are categorically broad ecological areas based on climatic conditions.
Characteristics include temperature ranges, precipitation levels, and dominant vegetation.
- Example: Temperate Forest biomes have broad ranges of temperatures and precipitation levels.

Tundra: Cold, short growing season, permafrost.
Taiga: Coniferous forests with more rainfall and a longer growing season than tundra.
Temperate Forest: Deciduous trees, rich biodiversity with moderate temperatures and consistent precipitation.
Grasslands: Areas characterized by grasses, influenced by grazing and fire disturbance patterns.
Deserts: Arid land with minimal vegetation, defined by high potential evapotranspiration compared to available moisture.

Chaparral: Plants adapted to fire and drought, found in breezy, dry conditions.
Aquatic Biomes: Distinguished between freshwater and saltwater ecosystems, dictated by movement patterns and biological dynamics.
- Characteristics can overlap but still follow the same ecological structuring.

The interconnectedness of climate, biomes, and ecological succession require a multifaceted understanding of ecological processes, which dictate how environments evolve over time.
Students are encouraged to engage with and read provided materials to reinforce the learning material for examinations and practical assessments.