Ecology Interactions in the biosphere depend on two

Ecology

• Interactions in the biosphere depend on two important categories of factors – biotic and abiotic

Biotic Factors • The living factors in an environment. • Includes all living organisms and their effects on other living things.

Abiotic Factors • The nonliving factors in an environment. • Includes water, O 2, light, temperature, soil, & nutrients.

Organization of the Bioshpere • Population: smallest grouping of organisms. • All individuals of a species that live in a certain area.

• Community: includes all populations in an area. • Ecosystem: includes a community and its physical environment. All ecosystems on earth are linked together.

Biodiversity • The variety of life in the world or in a particular habitat. • Greater biodiversity is a GOOD thing • What is better for the environment – a golf course or a forest?

Niche • The role and position a species has in its environment • How an organism meets its needs for food and shelter • Includes all of a species interactions with the biotic and abiotic factors in its environment • If two species are trying to occupy the same niche, they will compete = you are all trying to occupy the niche of valedictorian but only the “strongest” will survive

Population Dynamics • Populations can change size quickly & easily. • Grow when resources are not limited & when birth exceeds death.

Carrying Capacity • Limiting factors like disease, competition, & predation stop population growth. • Maximum population that can be supported.

• https: //www. youtube. com/watch? v=QI 2 ix. Je. Ix. EU

Organisms in an Ecosystem • Autotrophs: make their own food using CO 2. • Heterotophs: cannot make their own food, so they eat the autotrophs and other heterotrophs.

Types of Heterotrophs • Saprophytes, Herbivores, Carnivores, Omnivores

Saprophytes • Include heterotrophic plants, fungi, & bacteria which live on dead matter. • Recycle materials in the environment. • Mushrooms, mold, bacteria

Types of Symbiosis • Commensalism • Mutualism • Parasitism

Commensalism • One organism is benefited and the other is not affected • (+, 0) • Examples?

• https: //www. youtube. com/watch? v=lbm. Kqo. AYbdo

Mutualism • Both organisms benefit from the association. • (+, +) • Examples?

• https: //www. youtube. com/watch? v=Qqa 0 OPbdvjw

Parasitism • The parasite benefits at the expense of the host. • (+, -) • Examples?

• https: //www. youtube. com/watch? v=90 exk. FR 2 i. SM

Food Chain • A series of organisms through which food energy is passed in and through an ecosystem.

SUN (radiant energy) Energy

• Since practically all organisms may be consumed by more than 1 species, many interactions occur among food chains. • These interactions between food chains in an ecosystem are described as a food web!

What happens to the penguin population if the krill die off? What will happen to the algae? What happens to the squid population if the elephant seals overproduce? What will happen to the leopard seal?

https: //www. youtube. com/watch? v=-o. Vavgmvey. Y

Energy Pyramid • Top = Decomposers • Lower = Carnivores • Lower = Herbivores • Bottom = Producers

The Energy Pyramid

• There must be much more energy at the producer level in a food web than at the consumer levels! • Pyramid illustrates the loss of usable energy at each feeding level.

• Each consumer level utilizes about 10% of its nutrients to build new tissue. • This new tissue is the food for the next feeding level. • Remaining energy is lost as heat and unavailable chemical energy.

• Eventually, the energy in an ecosystem is lost and is radiated from the earth. • Thus, an ecosystem can’t sustain itself without the constant input of energy from the sun!

• https: //www. youtube. com/watch? v=c. Wh-XKhh 8 xo

Biomes!

• https: //www. youtube. com/watch? v=A 495 e 31 c. Dd. E

Succession is… • When ecosystems undergo change over time = evolution! • Living organisms change the environment, making it more suitable for some & less so for others.

PRIMARY SUCCESSION Begins from bare rock Occurs when life

PIONEER ORGANISMS First to inhabit an area Start process of soil formation. Lichen and moss

SECONDARY SUCCESSION Occurs when an ecosystem is upset and a new ecosystem takes

Follows a fire or clearcutting

Secondary Succession occurs more quickly than Primary

https: //www. youtube. com/watch? v=Ymrgo. CUj. HAw

3. Material Cycles Ø In a self-sustaining ecosystem, material must be cycled among the organisms and the abiotic environment. Thus, the same materials can be reused by different living organisms. Ø

Water Cycle Ø Water is vital to all living organisms and is a primary limiting factor within any

Carbon Cycle https: //www. youtube. com/watch? v=nz. Imo 8 k. SXi. U

https: //www. youtube. com/watch? v=dk 52 Hslj. VFA&index=12&list=PLAf. Hwv 37 -N_P 0 EPQs. Hgni 56 F 55 HEq. Oi. RW Ø The nitrogen cycle “recycles” the nitrogen necessary for the production of proteins, essential to all living things.

Plants use nitrogen for protein synthesis. Animals, which eat plants, convert the plant protein into animal protein.

Humans and the Environment! The bad news…

1. Negative Aspects Ø Natural systems have been upset because humans have not realized that we are PART of nature – not separated from it!

Human Population Growth Ø The total human population of the world has risen and is still increasing. Why? removal of disease • medical advances = increase of the average life span.

Human Population Expansion: https: //www. youtube. com/watch? v=v 28 Pk. XJI Ajs

Such activities include: 1. Overhunting: uncontrolled hunting, trapping, and fishing still occur in many parts of the world.

10 species that will soon be gone • https: //www. youtube. com/watch? v=fq. Xfefq 9 Vc. Q

2. Importation of Organisms: humans have accidentally and/or intentionally imported organisms to areas where they have no natural enemies – disrupts food webs.

Zebra Mussel https: //www. youtube. com/watch? v=ab. Imq. GDz. XBo

Purple Loosestrife https: //www. youtube. com/watch? v=Tm. Ms. I 3 ZYUq. I

Northern Snakehead Fish https: //www. youtube. com/watch? v=nm. U 7 et. SYYq. I

3. Exploitation: the exploitation of wildlife for their products and the pet trade has led to threatened populations and ecosystem disruptions.

Illegal pet trade • https: //www. youtube. com/watch? v=v 8 rz. MUhn 01 o

4. Deforestation: the extensive cutting down of tropical rain forests has led to habitat loss and erosion of topsoil.

deforestation https: //www. youtube. com/watch? v=M 4 jhjt 1_ey. M

5. Poor Land Use Management and Urban Sprawl https: //www. youtube. com/watch? v=r 2 Hz_C 3 XIpg

6. Water Pollution Ø Major water pollutants include: heat, sewage, phosphates, heavy metals, PCB’s and radioactive materials.

Ø These pollutants (toxins) cause harm to humans and wildlife. https: //www. youtube. com/watch? v=rre. BKDko 6 OY

7. Thermal Pollution The increased temperature of river water occurs when it’s taken from a river and used for cooling in factories and then returned to the waterway.

https: //www. youtube. com/watch? v=d. Ljow_j. Zj. LA

8. Air Pollution major air pollutants include: CO, hydrocarbons, and particulates. Ø NO and SO combine 2 with water vapor creating acid rain problems.

Acid rain has been responsible for the destruction of plants and animals in forests and bodies of water in North America and Europe.

Acid Rain in upstate NY https: //www. youtube. com/watch? v=6 oe 89 m. Dei 8 I

9. Global warming aka Climate Change The increasing levels of CO 2 have been linked to global warming. The Greenhouse Effect!

The greenhouse effect causing global warming… https: //www. youtube. com/watch? v=o. JAb. ATJC ugs

Ozone shield: the layer of the atmosphere that blocks out UV-radiation. Ø Compounds(CFC’s) in aerosol sprays and coolants have led to ozone depletion. This leads to higher cancer rates! THIS DOES NOT CAUSE GLOBAL WARMING!!!!!

Ozone hole reversing? • https: //www. youtube. com/watch? v=g. Eqi. HYTTCQA

10. Biocide Use: the use of biocides (pesticides and herbicide / poisons) has contaminated the soil, atmosphere, water supply, and has disrupted food webs.

DDT and biological magnification • https: //www. youtube. com/watch? v=L 8149 TO 0 EU 0

11. Disposal Problems the lifestyle of humans currently requires increasing products and energy, the production of which produces considerable wastes: solid, chemical, and nuclear.

12. Trade-offs • A situation that involves losing one quality or aspect of something in return for gaining another. • Losing a wetland in order to build a shopping mall is a trade-off. Species are usually moved to another location.

The good news…

1. Population Control: methods of controlling the human reproductive rate have been, and continue to be, developed. Ex) family planning

2. Conservation of Resources: In an attempt to reduce the loss of valuable agricultural land, reforestation and cover-cropping are serving as erosion controls. Ø Øhttps: //www. youtube. com/watch? v=g 2 i. Jca. Zh. I_8

Ø Along with maintaining valuable resources, the recycling of materials is reducing the need for landfills.

3. Pollution Controls: Ø Attempts are being made to control air and water pollution by law and by the development of new techniques for limiting pollution from cars, factories and sanitation.

4. Species Preservation: Ø Some efforts to sustain endangered species have included habitat protection (wildlife refuges and national parks) and wildlife management (game laws and fisheries).

The Bald Eagle https: //www. youtube. com/watch? v=ee. Icv. BNV m. Uc

5. Biological Control: Ø Using natural enemies of pest species to control population. ØUsing pheromones (hormones & scents)

This method is less likely to affect those species that are beneficial to humans, disrupt food webs, and contaminate the land. https: //www. youtube. com/w atch? v=Kq. Lx 6 jx. Ns. IA

Think Globally Act Locally