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Earth's Interior

• Earth's mantle is the mostly solid interior, lying between the core and crust.
• It's approximately 2,900 kilometers (1,802 miles) thick.
• The mantle comprises 84% of Earth's total volume.

Levels of Organization

• The biosphere is divided into five different biomes: tundra, grasslands, forests, deserts, and aquatic biomes.
• An ecosystem includes both biotic and abiotic factors.
• A community consists of interacting organisms (same or different species) coexisting in a particular area and time.
• A population encompasses all members of a particular species inhabiting a specific habitat.
• Organisms are the living entities composing the biosphere.

Biomes in BC

• Canada has four major biomes: tundra, desert, grassland, and forests.
• The Okanagan in BC has a semi-arid desert with low precipitation, hot summers (and cold nights), and dry winters.
• The temperate rainforest stretches along the BC coast from northern California to southern Alaska.
• Taiga (boreal forest). Boreal forest characterized by coniferous trees like spruces, larches, and pines.
• The taiga is the world's largest terrestrial biome.
• Alpine tundra is restricted to mountainous regions of BC and is characterized by cold temperatures (averaging between -4 and 0°C) and snow.

What is an Ecosystem?

• An ecosystem includes all biotic (living) and abiotic (non-living) factors within a specific region.
• These elements interact to form a balanced system.
• A community consists only of living things (plants and animals) in a specific region and how they interact.
• A biome spans a large geographic area defined by environmental conditions that determine which species can survive in each region.

Population Ecology

• Population ecology studies the structure and dynamics of populations.
• These involve biotic and abiotic factors that influence density, dispersion, and size within a population.
• A population is a group of individuals of the same species living in the same area.
• Population size can vary from a few to thousands of members.

Species, Populations, and Communities

• Populations are groups of the same species living in the same area.
• A community is a group of different species living in the same area.
• A species consists of organisms capable of interbreeding.

What is a Population?

• A population encompasses all members of a particular species that live in a particular area.
• A different population of a species will encompass all the members in a different set of defined locations.
• A species includes all organisms that share similar characteristics and can mate to produce fertile offspring. A population is a subset of that species.
• A community comprises all the different species inhabiting a specific area.

Species and Population Levels

• Species is a group of genetically linked individuals capable of interbreeding.
• Population is a group of organisms belonging to the same species in a particular region.
• Community is a group of populations of different species living in a particular area and interacting with each other.
• Ecosystem consists of all communities within an area, encompassing both biotic and abiotic factors.
• Biosphere is the narrow zone on Earth where life exists involving everything about life on our planet.

Distribution of Species and Populations

• Species are distributed using several parameters.
• Size of populations (and number of total individuals): Number of individuals.
• Density: Number of individuals per area.
• Dispersion: Arrangement of individuals in relation to one another (e.g., random, clumped, uniform).
• Occupancy: Habitat distribution, indicating the presence or absence of a species in each habitat.
• Population distribution: Location of a population across space.
• Geographic range: Span of a species' geographical limits, indicating its range.

Changes in Population Size

• Birth and immigration increase population size.
• Death and emigration decrease population size.

Estimating Population Size

• Quadrats are used for immobile or slow-moving organisms. A quadrat is a wooden, plastic or metal square used to estimate numbers of immobile individuals.
• Mark-recapture techniques are employed for smaller, mobile organisms, such as mammals. A sample of animals are captured, marked, and released to mix with the population.

Species Distribution Patterns

• Individuals in a population can be distributed randomly, in groups, or uniformly spaced.
• Important considerations include random, clumped, uniform distribution patterns.

Community Ecology

• Interacting populations within a habitat form an ecological community.
• The number of species within a community and their relative abundance is referred to as the diversity of the community.

Biogeochemical Cycles

• These cycles encompass the movement of nutrients and other elements between biotic and abiotic factors.
• Components like light, CO2, water, and others are cycled and recycled through various natural processes.

Types of Biogeochemical Cycles

• Gaseous cycles include the Carbon, Oxygen, Nitrogen and Water cycle.
• Sedimentary cycles include the Sulpur, Phosphorous, and Rock cycle.

The Water Cycle

• The water cycle (hydrologic cycle) involves the continuous circulation of water within the Earth-atmosphere system.
• It's driven by solar energy, which warms ocean surfaces causing evaporation, and ice to sublime (solidification to gas).
• Water exists in the atmosphere as water vapor.
• Water exists in various forms (like precipitation) across the Earth's surface.
• Water is also stored as freshwater in glaciers and ice caps and as groundwater in soil and various geological features.
• Various locations on Earth store water in different states.

Where is Earth's Water Located?

• About 96.5% of the Earth's water is located in oceans.
• About 1.7% is stored as polar ice, glaciers, and permanent snow.
• .001% of the Earth's water is in water vapor.
• The remaining water is in lakes, streams, rivers, and soil.

What are Decomposers?

• Decomposers are organisms, such as bacteria and fungi, that break down organic matter into simpler substances, thus releasing nutrients into the environment.
• Detritivores and saprophytes are two categories of decomposers.
• Scavengers are also decomposers that eat other animal's feces.

Key Points on Decomposers and Transformers

• Decomposers and transformers help maintain the dynamic structure of ecosystems. They break down dead organisms into simpler compounds.
• Transformers in ecosystems transform organic compounds into inorganic compounds for reuse by producers (plants).

Nitrogen Cycle

• Atmospheric nitrogen (N2) is converted into ammonia (NH3), a usable form for plants, through nitrogen fixation.
• This process includes lightning (physical) and biological fixation through non-symbiotic and symbiotic activities.
• The different forms of biological nitrogen fixation occur through particular microorganisms or bacteria and other microscopic life.

Steps in Nitrogen Cycle

• Atmospheric fixation is a natural phenomenon where lightning breaks nitrogen into nitrogen oxides, which are then used by plants.
• Industrial nitrogen fixation is a human process that contributes to nitrogen fixation.
• Biological nitrogen fixation involves bacteria (like Rhizobium) and blue-green algae transforming nitrogen into other compounds that plants can use.

Nitrification

• Nitrification is the process via which soil bacteria oxidize ammonia into nitrite and then into nitrate. Microorganisms like Nitrosomonas complete this reaction

Nitrogen Cycle Steps: Assimilation, Ammonification, and Denitrification

• Plants and animals absorb usable nitrogen compounds for biological processes.
• Ammonification involves the release of nitrogen compounds into the soil when plants or animals die.
• Denitrification returns nitrogen to the atmosphere as nitrogen gas.

Key Points on the Nitrogen Cycle and Methods

• The cycle involves microbial processes and atmospheric, industrial, and biological fixation.
• Different methods of converting and applying nitrogen to agriculture are relevant to environmental protection initiatives.

Carbon Cycle

• The carbon cycle is essential for life on Earth.
• Nature naturally balances the amount of carbon released from the environment with the amount of carbon absorbed.
• Humans have upset this balance via burning fossil fuels, which releases more carbon into the atmosphere than usual, leading to climate change.

Steps in Carbon Cycle

• Carbon moves from the atmosphere to plants as carbon dioxide (CO2).
• Plants, then, create their own food using photosynthesis and convert carbon dioxide into organic compounds.
• Carbon travels from plants to animals through food chains.
• Carbon returns to the atmosphere via respiration from animals and plants, and decomposition of organic matter.
• Combustion of fossil fuels in various industrial activities also releases carbon into the atmosphere.
• Oceans also incorporate and release carbon.

Fossil Fuels

• Fossil fuels are comprised of coal, oil, and natural gas.
• Collectively, they provide approximately 81 percent of the energy needs in the United States.
• They're used for heating and electricity generation in homes and businesses; and for running vehicles and factories.

Phosphorous Cycle

• The phosphorus cycle involves the movement of phosphorus through the biosphere.
• Phosphorus is predominantly found in phosphate compounds and in rocks.
• Geological uplifting processes move phosphorus to Earth's surface.
• Phosphorus can also be carried into waterways through runoff from agriculture.

Steps in Phosphorous Cycle

• Phosphate compounds in the soil can be taken up by plants and then transferred to animals.
• Phosphates are carried via surface runoff to rivers, lakes, and oceans, contributing to the phosphorus cycle.
• The breakdown of plants and animals releases phosphates.

Eutrophication

• Eutrophication occurs when too much nitrogen and phosphorus from fertilizer enter water bodies, causing algal blooms.
• These blooms deplete oxygen, creating "dead zones."
• Fertilizers containing excesses of nitrogen and phosphorus lead to excess amounts in runoff water and waterways.
• Algae production is enhanced which leads to the oxygen depletion in waterways, leading to fish suffocation.

Sulfur Cycle

• The sulfur cycle involves processes like volcanic eruptions, human emissions, and precipitation.
• The cycle encompasses the exchange of sulfur among different environments (like terrestrial and marine ecosystems.)
• The various forms and states of sulfur can exist in the environment.

Other Study Notes

• The text includes information about transpiration, evapotranspiration, and condensation, and other geological processes relevant to various cycles.
• The document further includes activity questions for each cycle.