Intro to Ecology + Global Abiotic Conditions (Day 5-6)

Ecology

Interactions of organisms with each other and with their environment

Abiotic vs. biotic

Nonliving vs. living

Scales of Ecology

• Individual

• Population (one species)

• Community (multiple species)

• Ecosystem (abiotic factors around them + multiple species)

• Biosphere (the Earth for us)

Organismal

Interactions of individuals with their environment (What kind of adaptations made for environment? How will organism respond to climate change?)

Populations

Group of individuals of the same species living in a specific area (How can we estimate population size (# of individuals)? What factors affect population size?) Boundaries may be unclear. Migration of individuals leading to inbreeding is common

Communities

Interactions among different species in a specific area (how do interactions with competitors, predators, and parasites affect abundance of a particular species and if a new one can come)

Ecosystems

Interactions between communities and their environments (What factors (now includes abiotic factors) affect ecosystem biodiversity and how does an ecosystem respond to change?)

Biosphere

Influence of energy on organisms across the planet (How does carbon capture by the Amazon rainforest affect global CO2 levels?)

Importance of ecology

• Management of resources: fishing/hunting, agriculture, ecosystem services

• Human health: “spillover” of disease from wildlife, human gut ecosystems

• Basic Science has value: understanding how environment sustains life on planet and drivers of evolution

Adaptations

Evolutionary process over generations which results in traits that increase survival and reproduction in an environment (ex: black-tailed jackrabbit having big ears to cool themselves and soles of feet covered in fur to protect from hot sand)

Acclimations

Short-term reversible adjustments of physiology/behavior to handle environmental stressors (black-tailed jackrabbit rests in shaded spots to avoid overheating and metabolism can adjust in response to heat)

Biogeography

Study of the distribution of living things and the abiotic factors that affect their distribution. Species distribution patterns are a result of biotic and abiotic interactions across evolution on large time scales.

Specialist Generalist scale

The scale can be used to show how comfortable in an environment and unable to adapt a certain animal is (specialists) or how well they can adapt in another environment (generalists). Can be in terms of many traits

Biome

Large geographic region characterized by a specific set of environmental conditions. ALSO INCLUDES the biological community that has formed in response to the physical environment

How is ecosystems different from biomes

They’re more specific as in they point towards a specific area (ex: a specific forest in England)

Water Biomes

Freshwater and Marine

Freshwater Ecosystems

• Streams, rivers, ponds, and lakes

• Rivers and streams: 0.0002% of Earth’s water, animals adapt to the current, strong currents affect plant and algal growth

• Ponds and Lakes: 0.007% of Earth’s water, ponds are shallow enough for sunlight to reach bottom letting plants grow, lakes and large ponds are too deep for plants to grow on the bottom, lower in oxygen than streams

Marine ecosystems

• 96.5% of Earth’s water

• Estuary: Where freshwater of a river meets saltwater of the ocean, intermediate salinity

• Intertidal Zone: the area between the highest high tide and the low tide line, organisms here must be able to survive pounding waves, water level changes, and temp changes. Barnacles, starfish, snails, clams + more

• Neritic Zone: the area below the low tide line which extends over the continental shelf, sunlight passes thru zone so plants can do photosynthesis, coral reefs may form in warm water

• Open ocean: 2 zones - surface zone which first few hundred meters deep of ocean where light penetrates and deep zone which is lower and totally dark

How are land biomes often classified and determined

By dryness (precipitation) and climate + temperature over space and time

Tropical rain forests

• Found in regions close to the equator

• Warm and humid all year long

• Lots of rain

• Diverse plant growth

• The trees from several layers. Examples are canopy (leafy roof formed by tallest trees) and understory (second layer of shorter trees and vines that must grow well in shade)

Temperate deciduous forests

• “Temperate” = having moderate temperatures

• Deciduous = dominated by trees that lose their leaves in fall

• Northwestern coast of U.S. is a temperate rain forest

• Lots of rain

• Huge trees: Cedars, Redwoods, Douglas Firs

Boreal Forests (Taiga)

• Typically dominated by conifers (spruce, pine, etc.)

• 11.5% of Earth’s land area

• Low annual temperatures

Grasslands

• Grassland (prairie) = An area populated mostly by grasses and other non-woody plants

• Low to moderate amount of rain

• Fires and droughts are common

• Home to many of the largest animals on Earth (ex: elephants, buffalo)

• Grazing by these large herbivores helps to maintain these grasslands

Chaparral

• “Shrubland”

• Mild wet winters, hot dry summers

• Infrequent, high-intensity fires

Deserts

• Desert = area that receives less than 25 cm of rain per year

• Some deserts receive NO precipitation at all during one year

• Deserts often undergo large shifts in temperature during the course of a day (hot during day, cold during night)

Tundra

• Extremely cold and dry

• Usually receives no more precipitation than a desert biome (sometimes is considered a desert)

• Most soil is frozen all year long (permafrost)

• During summer, the top layer of soil thaws, but the rest remains frozen

• Bc rainwater can’t soak into permafrost, many shallow pond and marshy areas during summer

How are you going to study for biomes

Using the chart on the Day 5 slides, reminder to do that

How do specialist species adapt to their environment

They fine-tune their diets and behaviors in order to match their extremely specific environment

Abiotic factors examples

• Water, Minerals, Nutrients, Tides

• Light, Radiation

• Temp, Humidity, Acidity, Salinity, Precipitation

• Wind, Dissolved oxygen, Altitude

What can limit species dispersal

Area inaccessible or insufficient time, predation, parasitism, competition, disease, abiotic factors

Correlation between sunlight and vegetation

More sunlight = more vegetation

How do temperature, precipitation, and latitude interact

The closer the latitude is to 0, the higher the temp and precipitation

Temp and altitude/elevation correlation

More altitude and elevation gets more towards where the atmosphere gets thinner and farther away from warm surface of Earth, causing temp to go down

Hadley cells

• The correlation of temperature, precipitation and latitude

• Collisions of air currents causes air to rise and go to the ends of the Earth (latitude increases)

• Cooling of air causes precipitation to fall and the air to warm, returning to the equator (latitude decreases)

• Deserts are dry because they’re in the area where the air is warm but not enough precipitation while rainforests are on the equator where precipitation is high with temperature

How does Earth spinning on it’s axis give us seasons

Its tilt and rotation give us our season by pointing some parts of itself to the sun while the other is facing away. That’s the reason why the time of US winter is New Zealand’s summer

Coriolis Effect on general wind direction

It explains that the Earth rotates faster at the equator, which causes surface winds. As the latitude increases, the Coriolis effect bends those wind currents causing the major global wind belts.

Temp and day length correlation with the equator

Bc less environmental stress, closer to the equator makes them more consistent

Rain Shadows

Moisture filled air blows from oceans, the air rises over the mountain and cools, causing precipitation. However, the mountain blocks and area behind it, creating what’s being defined.

El Nino Conditions vs La Nina Conditions

Lower and calmer winds which are warmer while the other is higher and colder winds. Both unpredictable and irregular patterns that happen every 2-7 years

El Nino effects on weather

For winter, it causes areas closer to it to be wetter, farther away to be hotter, and areas more right are drier

La Nina effects on weather

For winter, it causes areas above it to be colder, areas under but close to be wetter, and areas farther away but under to be drier

How can different soil can affect the type of biome

• Cascading effects on soil: warm, humid, environments, with more rain, have more acidic soils

• pH of soil depends on parent material (rock) and other processes

Why can the underground be warmer than the surface

When the surface becomes cold, the underground can hold onto that thermal energy.