Bell Work

• Describe the process of recycling paper.

Intro to Biology – Lecture 31

Conserving Resources

What does this symbol mean?

Recycling

• Processing used materials (waste) into new products

Why is Recycling Useful?

• to prevent waste of potentially useful materials

• to reduce the consumption of fresh raw materials

• to reduce energy usage• to reduce air and water pollution

Energy for Recycling

• All forms of recycling use energy in the process of putting material resources back into use.

Recycling in Ecology

• Ecosystems use the diversity of food webs to recycle natural materials, such as mineral nutrients, which includes water.

Recycling in Ecology

• Regulated during the process of decomposition

• Nutrients are broken down by decomposers and returned to the soil to be used by plants.

Ecological Recycling

• Also known as the nutrient system.• An ecosystem functions as a unit

Recycling Matter

• Matter is recycled through an ecosystem through cycles

• Different animals with different eating habits help to recycle matter (carnivores, producers, herbivores, omnivores, scavengers, and decomposers).

Law of Conservation of Matter or Mass

• Matter can neither be created nor destroyed and that nature is essentially a closed system.

Within an Ecosystem

• Matter and energy are transferred • Nutrient cycling occurs in ecosystems that

participate in large scale energy transfers throughout the system.

Recycling is Natural

• The conservation of resources is a natural, almost unnoticeable process.

• Life substances are recycled in the ecosystem

Recycling in an Ecosystem

• The nutrient cycle is nature's recycling system

The Nutrient Cycle

• A nutrient cycle is nature's way of ensuring life can carry on in the closed system called Earth.

What is a Closed System?

• Nothing is inputted or outputted from the system

Nature is a Closed System

• This means that all the elements we rely on to support life on the planet are here and have been here since the beginning.

Where Nutrients are Shared

• Biogeochemical cycles are complex ways that chemical elements and compounds move between the atmosphere, the soils (lithosphere) living organisms (biosphere) and oceans, lakes etc. (hydrosphere).

How this Relates to Recycling

• In order for life to continue, each cycle must remain in motion.

• Once a living thing has finished using a nutrient and either excretes it or drops dead, the nutrient must cycle back for some other living thing to use it.

Recycling Elements

• About 95% of the total mass of all living things are made up of six elements: hydrogen, oxygen, carbon, nitrogen, phosphorus and sulfur.

• The nutrient cycles work to keep these elements in circulation.

The Nutrient Recycling Cycles

• Each cycle has a complex variety of pathways it can take to keep the nutrient moving through the system.

The Recycling Cycles

• The water cycle (hydrogen and oxygen)• The carbon cycle• The sulfur cycle• The phosphorus cycle• The nitrogen cycle

The Two Important Cycles

• Nitrogen cycle and Phosphorus cycle are the most important to life.

• This is because the most common limiting factors for growth are inadequate nitrogen or inaccessible phosphorus.

A Form of Recycling

• Composting – keeps important nutrients in circulation

• Throwing items away in plastic bags takes those molecules out of the nutrient cycles indefinitely.