Nutrient Cycling in the Biosphere

Nutrient Cycles Cycling maintains homeostasis (balance) in the environment. 3 cycles to investigate: 1. Water cycle 2. Carbon cycle 3. Nitrogen cycle

Water cycle- 4 stages Evaporation – liquid turns to vapor Transpiration – Loss of vapor to atmosphere Condensation – Vapor in atmosphere cools to a liquid in clouds Precipitation – Liquid water returns to Earth.

Water cycle-

Carbon cycle- Photosynthesis and respiration cycle carbon and oxygen through the environment. Involves both autotrophs and heterotrophs. CO 2 O2O2

Carbon cycle-

Nitrogen cycle- Atmospheric nitrogen (N 2 ) makes up nearly 78%-80% of air. Organisms can not use it in that form. Lightning and bacteria convert nitrogen into usable forms.

Nitrogen cycle- Only in certain bacteria and industrial technologies can fix nitrogen. Nitrogen fixation-convert atmospheric nitrogen (N 2 ) into ammonium (NH 4 + ) which can be used to make organic compounds like amino acids. Nitrogen-fixing cyanobacteria are essential to maintaining the fertility of semi-aquatic environments like rice paddies.

Nitrogen cycle- Nitrogen-fixing bacteria: Some nitrogen-fixing bacteria live free in the soil. * Some live in a symbiotic relationship with plants of the legume family (e.g., soybeans, clover, peanuts).

Atmospheric nitrogen Lightning Nitrogen fixing bacteria Ammonium Nitrification by bacteria NitritesNitrates Denitrification by bacteria Plants Animals Decomposers Nitrogen Cycle

Other resources In our planet, there are abiotic factors that are important to many species (including humans) to survive. Ex) Natural resources There are 2 types of resources used by organisms – Renewable and Non- renewable resources.

NONRENEWABLE RESOURCES A nonrenewable resource is a natural resource that cannot be re-made or re-grown at a scale comparable to its consumption.

NUCLEAR ENERGY Nuclear fission uses uranium to create energy. Nuclear energy is a nonrenewable resource because once the uranium is used, it is gone!

COAL, PETROLEUM, AND GAS Coal, petroleum, and natural gas are considered nonrenewable because they can not be replenished in a short period of time. These are called fossil fuels.

HOW IS COAL MADE ???

HOW ARE OIL AND GAS MADE ???

RENEWABLE RESOURCES Renewable resources are natural resources that can be replenished in a short period of time. ● Solar ● Geothermal ● Wind ● Biomass ● Water

SOLAR Energy from the sun. Why is energy from the sun renewable?

GEOTHERMAL Energy from Earth’s heat. Why is energy from the heat of the Earth renewable?

WIND POWER Energy from the wind. Why is energy from the wind renewable?

BIOMASS Energy from burning organic or living matter. Why is energy from biomass renewable?

WATER or HYDROELECTRIC Energy from the flow of water. Why is energy of flowing water renewable?