Balance to Ecosystems and Human Influence

Natural Balance to Biogeochemical Cycles• Carbon / Oxygen– Carbon and oygen is stored in tissues as carbohydrates, lipids, and

proteins– Methane (CH4) and Carbon Dioxide (CO2) are released into

atmosphere– Combustion (burning) of wood or other carbon based fuels release

CO2

– Weathering of carbonate rocks releases carbon– Photosynthesis takes in atmospheric CO2 and make glucose from it

for energy– Cellular respiration (in all organisms using oxygen) breaks down

glucose for energy and releases CO2

– Oxygen is also used to make upper atmosphere ozone (O3) needed for UV light protection

Natural Balance Cont.

• Nitrogen– Needed for making amino acids and proteins– Bacteria is necessary for nitrogen conversions to

usable forms• Nitrogen fixing bacteria • Nitrifying bacteria• Decomposing bacteria for ammonification• Denitrifying bacteria

Natural Balance Cont.

• Hydrologic Cycle (Water Cycle)– Driven by Sun’s energy (causes evaporation)– Used by organisms• Photosynthesis• Transpiration• Respiration• Elimination• Blood and/or body fluids

– Cleansing of air impurities with precipitation

•Greenhouse Effect is necessary and normal•Greenhouse gases include CO2, O2, CH4, and water vapor

Human Population• Human Population Clock•Human Population on this planet is roughly 6.7 billion people•The population is in a period of exponential growth, doubling every ~60 yrs•2070 =~13.4 billion people•Growth Rate- 1.14%

• ~75 Million people/ yr• ~203,000 people /day

•27% of the world is under age 15

Factors Affecting Population Growth

Death Rates

-Personal Hygiene improvements

-Improved Sanitation

-Improved Medical Practice/ Access

Birth Rates

-Health & Wellness Education

-Education of Women

-Access to Contraceptives

-Family Choice for Smaller Families(cost Vs. necessity)

-Spread of HIV/AIDS

Age Structure Diagrams• Shows the number of males and female in

each age group( cohort) for a population

Three growth pattern types:

Rapid( Developing country)

Slow or Decline( Developed Nations)

Resources – Striving for Sustainability (keeping the resource managed for long periods of time)

•Renewable – Resources that can be replenished in a short period of time

• Trees• Wind power• Water (if treated at a rate faster than use)• Compost / Organic Fertilizer• Soil (if best management practices are followed)• Solar power

•Nonrenewable - Resources that can be replenished• Fossil Fuels • Soils (if not managed)• Water (if not purified at a fast rate)• Minerals (if not recycled)

Human Factors Affecting the Environment

*Fertile Soil Depletion*Ozone depletion by CFC’s (choloflorocarbons) – causes increased rates of skin cancer•Pesticide Resistance*Solid waste disposal issues•Mining•Global Warming•Acid Rain•Habitat Destruction

Global Warming

AKA -Global Climate Change

Natural Process that is being sped up by human activity

*Global Temp has increased 1.4 oF (0.8 oC)

*The ‘80s and ‘90s were the warmest on record

*Rate of temperature in the Arctic is twice that of the rest of the globe

*Sea ice loss is damaging polar bear and Arctic populations

*Glaciers are receding. Glacier Nat’l Park has lost 123 Glaciers since 1910

*Sea temp rises are bleaching coral reefs

*Incidence of Wild Weather is increasing. (Wild fires, hurricanes, etc.)

C) Acid Rain

Acid Rain- any form of precipitation that is unusually acidic

*Normal Rain pH 5.6 --> Acid Rain pH ~3

*Can be rain, sleet, snow or fog

Caused by the mixing of SO2 and NOX with atmospheric water forming sulfuric acid and nitrous acids

-Major source- Electric Power Production

Negatively affects plants, animals, aquatic ecosystems and infrastructure

In the US the major affected area is in the New England area, though the industrial contributors are mainly located in the mid-west, thanks to the wind

Resulting in Dead Lakes and Stripped Forests

Aquatic Species Range of Tolerance

Mt. Mitchell, NC

SolutionsUse of scrubbers on industrial smoke stacks

Use of catalytic converters on cars

Reduce emissions from cars through public transit, HOV lanes

Restore damaged ecosystems

Push for use of alternative energy sources

D) Resource Use and Loss

Food for Thoughtactivity

Habitat Destruction-when a natural habitat is rendered incapable of sustaining its current species

In the Amazon -22,392 km2 per year is deforested

Leading cause of Extinction worldwide

Causes: Agriculture (#1)

Mining, Logging, Urban Sprawl and Infrastructure

Habitat Fragmentation, Climate Change

Introduced Species

Species Extinction- the end of a species, locally or globally

-Roughly 3 species per hour, most we don’t even know of yet

Introduced Species-a species that has been transplanted outside its normal(native) geographic range, though the actions of humans. The term invasive species describes species that act as pest.

Amazon Jungle 2000

Deforestation 2008Amazon Clearing

Mexican Jungle after burning

Habitat Destruction

http://www.conservation.org/act/get_involved/pages/stoptheclock.aspx

Dodo Bird-1681 Golden Toad-1989 Bali Tiger-1937

Passenger Pigeon-1914 Carolina Parakeet-1939

Extinct Species

Cane Toad-Australia Red Fox-Australia Zebra Mussel-US

Kudzu-Everywhere Eura. Tree Sparrow-US European Starling- US

Introduced Species

Hemlock Wooly Adelgid Gypsy Moth Defoliation-PA

Biological Control-the use of predators or parasites to control agricultural pests or invasive species

Failure

Cane Toad introduced in 1930’s to control Sugar Cane beetles

Cane Toad is a generalist. Instead they consumed food closer to the ground, where it was, since its size limits its mobility

Success

Alligator Weed is native to South America, but in US clogs waterways and out competes native species

Alligator weed is biologically controlled through a team of specialist insects

Alligator Weed Thrips -terrestrial foliage Alligator Weed Stem Borer-

stemsAlligator Weed Flea Beetle- foliage & stems