Intro to ecology and the abiotic environment

What is the science of ecology? Define ecology.

The scientific study of interactions between organisms and their environment 

Provide 5 examples each of abiotic vs. biotic environmental components. 

Aboitic: sunlight, temperature, water, soil, and air 

Biotic: plants, animals. Fungi, bacteria, protists 

How do the fields of Environmental Science and Natural History differ from Ecology?

Environmental science focuses on human-environment interactions; natural history focuses on observing organisms in the wild, and ecology is the scientific study of interactions among organisms and their environment.

1. What is the goal of ecology?

The goal of ecology is to understand the distribution and abundance of organisms, the interactions that influence them, and how energy and matter move through ecosystems.

What is the difference between the “distribution” of an organism and the “abundance” of an organism?

Distribution: is where species are found geographically 

 Abundance: is how many individuals of a species are present

1. What are the 5 organizational scales of Ecology? 

1. Organism - an individual living thing, and how it interacts with its environment

2. Population - a group of individuals of the same species living in the same area

3. Community - all the different populations living and interacting in an area

4. Ecosystem - the community plus the abiotic environment

5. Biosphere - all ecosystems on earth; the entire zone where life exists

1. What are the 3 research tools/approaches that ecologists utilize? How does an observational study differ from an experimental study?

1. Observational studies - ecologist watch and measure organisms in their natural environment 

2. Experimental studies - ecologists manipulate one or more variables to test a hypothesis. Allows for cause and effect 

3. Modeling - using mathematical models, computer simulations, or conceptual diagrams to predict ecological patterns 

An observational study ONLY observes natural patterns; an experimental study, researchers change or control a variable. Includes treatment vs control groups.

1. What is the approximate timescale of weather?

Short timescale - typically hours to days

What is the approximate timescale of climates? Provide 3 examples of climate patterns.

Long timescale - usually decades to thousands of years 

Three types are: 

1. Average annual temperature 

2. Average annual precipitation 

3. Seasonality

1. Why is the weather not predictive of climate?

They operate on different timescales and describe different kinds of patterns. Weather = short-term (hour to hour) 

Climate - long-term

Which latitude receives the most energy from the sun?

1. The equator 

How does the sun’s energy reaching the earth change towards the poles?

Decreases. Sunlight is hit at a lower angle (the sunlight arrives more slanted)

Which two factors drive this spatial pattern in sunlight?

1.  The curvature of the Earth and the tilt of Earth’s axis (23.5 tilt)

Which two factors drive seasonality in temperature?

1.  Earth axial tilt and earth’s orbit around the sun

Where on earth is seasonality the strongest? Weakest?

1. Strongest: high latitudes - places far from the equator, such as poles and temperate regions (Canada, Russia). Weakest: Low latitudes - places near the equator 

During which time of the year is it coldest in Rio de Janeiro, Brazil?

1. June, july, august. Since Rio is tilted away from the sun during this part of the orbit 

What would the Earth were tilted at a more extreme angle? How would the Earth’s climate change in this scenario?

1.  Season would become much more extreme - summers would be hotter, winter would be cooler and much stronger seasonal differences at higher latitudes.

 What are the 4 major components of climate?

Temperature, precipitation, sunlight, and wind

What are the major trends in global temperature variation? In other words, how does mean average temperature change from the equator to the poles?

The mean annual temperature decreases. The equator receives the most direct sunlight tropics → Temperate zones: Gradual cooling as solar energy becomes less concentrated. Poles: coldest temperatures – sunlight arrives at a very low angle and for fewer hours per year

 What drives this pattern of global variation in temperature?

The angles of the sun’s ray and the amount of atmosphere sunlight must pass through, which causes equatorial regions to receive more energy than the poles.

What are the major trends in global precipitation variation? In other words, how does the mean average precipitation change from the equator to the poles?

Precipitation is highest at the equator, lowest at 30 (deserts), increases again around 60, and then becomes very low at the poles. 

What drives global variation in precipitation? In other words, how do air circulation cells explain wet tropics and dry deserts?

Global precipitation varies because rising air at the equator produces wet tropics, while sinking air at 30 degrees latitude creates the world’s major deserts

What would happen if air circulation cells were reversed in direction? Which areas would be dry, and which would be wet? What would happen if air circulation cells were reversed in direction? Which areas would be dry, and which would be wet?

If air circulation cells reversed, the equator would become dry, 30 degrees N/S would become wet, mid-latitudes would be dry and the poles would be wet.

Why are sites at high elevation colder and sites at low elevation warmer, even when these sites might share the same latitude?

 Higher elevations are colder because air pressure is lower and rising air cools as it expands, while low elevations are warmer because dense air holds more heat. 

Why is the west coast of South America cooler than the east coast of South America?

 The west coast is cooler because a cold ocean current flows along it, while the east coast is warmer because it is influenced by a warm current.

What is meant by the term “microclimate”? Provide 3 examples of microclimate.

 Microclimate is a small, localized area with climate conditions that differ from the surrounding regions. 

Three example: 

1. Forest understory 

2. Urban areas

3. Valleys or mountain slopes