Unit 1: The Living World (Ecosystems) 1.1-1.4

Environment

The sum of all the conditions surrounding us that influence life

Environmental science vs Environmentalism

-Interactions among human systems and those found in nature

vs

-Social movement that seeks to protect the environment through lobbying, activism, and education

APES - Four "Big Ideas"

-Energy Transfer

-Interactions Between Earth's Systems

-Interactions Between Different Species and the Environment

-Sustainability

Energy Transfer

-Conversion and transfer of energy among different components of systems (whether natural or manmade)

Interactions Between Earth's Systems

-Humans and natural factors influence Earth's systems.

Interactions Between Different Species and the Environment

-Life on Earth present for 4.5 by, but human life only past 2.5 my.

-Human tech has a profound impact on the nat'l environ

Sustainability

-Using Earth's resources in a way that doesn't jeopardize future generations

Dependent and Independent variables

-Dependent variables: factors which are being measured

-Independent variables: factors which are not being measured.

Accuracy vs Precision

-Accuracy: how close to true value

-Precision: How close repeated measurements are to eachother

Uncertainty

-Estimate of how much a value differs from the true value

Community Ecology

-The study of interactions among species.

-Consumption, competition, symbiosis.

Ecosystem

-A biological community of interacting organisms and their physical environment.

-Ecosystem boundaries are determined by abiotic and biotic factors, such as temperature, salinity, soil, etc --> can vary in size

Gause's Law (Competitive Exclusion Principle)

-Two species competing for the same resource cannot reasonably coexist.

-Negative Negative

-^leads too the extinction of the weaker competitor, or evolutionary/behavioral shift toward a different ecological niche

Resource partitioning

-Two species evolve to divide a resource through behavior or morphology in order to avoid competition.

Predation

-One animal kills and consumes another animal, in order to consume their energy. (Wolf hunting moose)

-Positive Negative

Parasitism

-One organism lives on or in another organism, consuming a small fraction of the host in order to keep it alive.

-^Sometimes consumes their prey by laying eggs inside the host organism, which then hatch and slowly consume it from the inside

-Positive Negative

Pathogens

-NOT PARASITES!

-Organisms that cause disease (viruses, bacteria, fungi, protists, and helminths worm-like parasites)

Herbivory

-Animals that only eat plants.

-An increase in herbivores can lead to collapse of ecosystems, so predation can sometimes keep them under control

-Positive Negative

Morphological defenses

-Camouflage, sharp spines, chemical defenses, mimicry

Mutualism

-A relationship between two species in which both species benefit

-Positive Positive

-EX: bees and flowers

Commensalism.

-A relationship between two organisms in which one organism benefits and the other is unaffected

-Positive Zero

-EX: bird and tree

Invasive Species

-Species that spread quickly and cause harm to native ecosystems

Exotic/non-native/cultivated species

-Those that are out of their historical range and can have an impact on those native species.

"Biome"

-A region of the world where particular plants and animals can be found.

Terrestrial biomes

-Defined by the dominant plant growth forms as well as annual temperature and precipitation

-Tundra and taiga biomes

-Temperate biomes

-Tropical biomes

Habitat

-Where a particular species lives in nature, not characterized by plants.

-Different from biome (smaller vs bigger)

Tundra

-A cold and treeless biome with low-growing vegetation defined by permafrost, a frozen layer of soil that prevents drainage.

-Average Precipitation (mm): 0-100

-Average Temp (C): -20-10

-Arctic fox, snowy owl

-Only in north bc no land in southern hemisphere

Taiga/coniferous/boreal

-A forest biome made of primarily coniferous evergreen trees that tolerate cold winters and short growing seasons, sometimes referred to as a boreal forest.

-Average Precipitation (mm): 0-100

-Average Temp: -20-20

-Spruce, evergreen

-Only in north bc no land in southern hemisphere

Temperate Rainforest

-A coastal biome typified by moderate temperatures and high precipitation

-Average Precipitation (mm): 0-200

-Average Temp: 0-20

Temperate Seasonal/ Deciduous Forest

-A biome with warm summers and cold winders with over 1 meter (39 inches) of annual precipitation.

-New Jersey!!!!

-Average Precipitation (mm): 0-100

-Average Temp: 0-20

Shrubland/Woodland

-Characterized by hot, dry summers, and mild, rainy winters

-Average Precipitation (mm): 0-100

-Average Temp: 10-20

Temperate grassland/cold desert

-Sometimes referred to as a cold

desert, typically has cold, harsh

winters and hot, dry summers

-Average Precipitation (mm): 0-100

-Average Temp: 0-25

Tropical Rainforest

-Warm and wet biome found between 20° N and 20° S of the equator, with little seasonal temperature variation, and high precipitation, soils are typically poor (heat + water = weathering and erosion)

-Average Precipitation (mm): 200-400

-Average Temp: 20-30

Savana

-Also known as tropical seasonal forest, is known for warm temperatures and distinct wet and dry seasons

-Average Precipitation (mm): 0-200

-Average Temp: 10-25

Hot Desert

-Located at roughly 30° N and 30° S with hot temperatures, extremely dry conditions, and sparse vegetation

-Average Precipitation (mm): 0

-Average Temp: 10-20

Aquatic Biomes

-Characterized by different means, such as salinity, depth, and water flow

-Freshwater

-^Streams, rivers, lakes, and wetlands

-Marine (Seawater)

-^Estuaries (where freshwater rivers meet ocean water), coral reefs, and open ocean

Freshwater biomes: Rivers and Streams

-Low salinity and are categorized as streams, rivers, lakes, ponds, and freshwater wetlands.

-MUST have flowing freshwater.

-Fast-moving streams tend to combine, forming rivers, which then slow down.

-Streams tend to have few plants and algae

-^When combined into a slower moving river, more sediments and organic material settle so plant growth

Freshwater biomes : Lakes/ponds - zones

-Lakes and ponds tend to have standing water, and may be too deep to support vegetation except near the shorelines, or the littoral zone (shallow down-sloping shelf).

-Limnetic zone: layer that receives

sufficient sunlight, allowing for photosynthesis. AKA “photic zone”. Photosynthetic algae!

-Profundal zone: Areas WITHOUT sunlight

-Benthic zone: BOTTOM of lake, pond, or ocean.

Classification of lakes through nutrients

-Oligotrophic lake = LOW amount of nutrients

-Mesotrophic lake = MODERATE amount of nutrients

-Eutrophic lake = HIGH amount of nutrients

-^Eutrophic lakes can have high concentrations of algae which block light → underwater plants can not perform photosynthesis!

Freshwater biomes : Freshwater wetlands

-Land that is saturated by water for at least part of the year, but shallow enough to support vegetation.

-Many bird species depend on wetlands during migration and breeding seasons.

-Much of these areas have been drained for agriculture and development.

-Marshes, swamps, bogs, fens, etc.

Marine biomes

-Characterized by salt water

-Estuaries/salt marshes

-Mangrove swamps

-Intertidal zones

-Open ocean

Marine biomes : Estuaries

-Near coast lines where rivers of freshwater and saltwater from the ocean combine --> Mark transition zone from land to sea.

-Tend to carry nutrients from rivers; estuaries then become very productive areas, and can help filter contaminants.

-Lack of biodiversity

-brackish water

Marine biomes: Salt Marshes

-Coastal wetlands that are defined by the areas flooded with saltwater and subsequently drained (often based on tide cycles)

-The safety provided by both estuaries and salt marshes mean that they tend to be nurseries for fish and other organisms.

Marine biomes: Mangrove Swamps

-Occur near tropical and subtropical coasts, and are characterized by mangroves with roots that rise above water to survive high salt content.

Marine biomes: Intertidal zones

-Narrow bands of coastline that exist between high and low tide.

-Many species must adapt to extreme temperatures and desiccation (loss of moisture)

Marine biomes: Coral Reefs

-Earth's most diverse marine biome, found in warm shallow waters beyond the shoreline in tropical regions.

-They are characterized by symbiotic coral species that are prone to coral bleaching.

Flowing water: Freshwater (low salinity) vs Marine (high salinity)

-Streams and Rivers

-Estuaries/salt marshes, mangrove swamps

Standing water, Deep water: Freshwater (low salinity) vs Marine (high salinity)

-Ponds and lakes

-Open Ocean

Standing water, Shallow water: Freshwater (low salinity) vs Marine (high salinity)

-Freshwater wetlands

-Coral reefs

Fluctuating water depths: Freshwater (low salinity) vs Marine (high salinity)

-N/A

-Intertidal zones