HUMAN IMPACT on the BIOSPHERE Part 3 BIODIVERSITY http://www.millan.net

BIODIVERSITY The sum of the genetically based variety of all the organisms in the biosphere = ___________________ Biodiversity gives __________ to the ecosystems that we are so dependent on, enhances their ____________, and provides an important source of new _____, ________, and other _________. BIODIVERSITY stability productivity medicine food products

BIODIVERSITY THREAT habitat destruction Development of natural areas for cities or agriculture results in ____________________ habitat destruction http://www.simtropolis.com/idealbb/files/SG_ShoppingCenter.JPG

http://www.abc.net.au/news/newsitems/200506/s1384632.htm BIODIVERSITY THREAT Changes in Brazilian rainforest over 30 years The tropical rainforests once covered more than 14% of the earth's total land surface, but now cover less than 6%.

BIODIVERSITY THREAT Habitat fragmentation Splitting a habitat into smaller disconnected pieces = _____________________ It results in small “islands” of natural area isolated from each other by crop land, pasture, pavement, or even barren land. Habitat fragmentation http://en.wikipedia.org/wiki/Habitat_fragmentation

BIODIVERSITY THREAT Habitat fragmentation brings wildlife in more frequent contact with humans. When it comes down to “us or them” . . . “they” usually lose. http://www.chrismadden.co.uk/eco/peterrabbit.html

BIODIVERSITY THREAT INVASIVE SPECIES PREDATORS INCREASE One of most important threats to biodiversity come from apparently harmless plants or animals that humans transport into new habitats = _____________________ New habitats don’t have ____________ and parasites that control the population in their native habitats, so invasive species populations _____________ rapidly. INVASIVE SPECIES PREDATORS INCREASE

EXAMPLES OF INVASIVE SPECIES http://psephos.adam-carr.net/countries/a/australia/images/australiamap.gif 24 rabbits turned loose for hunting in 1859 in Australia, reproduced at such a rapid rate they have taken over the continent. Within 10 years they had multiplied so rapidly, 2 million rabbits a year could be shot or trapped without any noticeable effect on population. http://en.wikipedia.org/wiki/Image:Wild_rabbit.jpg

EXAMPLES OF INVASIVE SPECIES http://en.wikipedia.org/wiki/Image:Rabbit-erosion.jpg They are believed to be responsible for the _______________ of 1/8 of the mammal species, unknown numbers of plant species, as well as serious ________________ problems. It is still a major problem and rabbit diseases have been purposely introduced to try to control the population. extinction soil erosion. http://www.csiro.au/communication/rabbits/qa1.htm

EXAMPLES OF INVASIVE SPECIES Zebra mussels _________________ are native to the Caspian Sea region of Asia. They are believed to have been transported to the Great Lakes in the ballast water from a ship. They were first discovered in 1988, and have since spread rapidly to all of the Great Lakes and waterways in many States and into Canada. http://en.wikipedia.org/wiki/Image:Dreissena_polymorpha3.jpg

PROBLEMS CAUSED BY ZEBRA MUSSELS Clog power plant and public water intakes and pipes, costing taxpayers millions of dollars · Damage boat engines · Blanket shorelines with their sharp shells and foul smell · Consume available food for native species and smother native mussels · Threaten water-based recreational activities http://en.wikipedia.org/wiki/Zebra_mussel

EXAMPLES OF INVASIVE SPECIES Kudzu There's so much of this fast-growing vine in the Southeastern U.S., you might think it was a native plant. Actually, it took a lot of hard work to help kudzu spread so widely. Now that it covers over seven million acres of the deep South, there are a lot of people working hard to get rid of it! But kudzu is used in ways which might surprise you...

BIODIVERSITY THREAT pollutants The addition of ________________ = harmful materials that can enter the biosphere through land, water or air can also threaten biodiversity. http://www.kidcrosswords.com/kidoutdoors/the%20environment/pollution_smokestacks.jpg http://www.iol.ie/~carigeen/pollution.jpg

_____ was first modern insecticide Example: _____ was first modern insecticide It was cheap, stayed active for long time, and kills many different insects Used to control agriculture pests and disease carrying _______________ DDT MOSQUITOES http://www.michigan.gov/images/mosquito_65147_7.jpg

drained into rivers and streams at LOW concentrations. When DDT was sprayed, it drained into rivers and streams at LOW concentrations. http://www.ci.cypress.ca.us/public_works/stormwater_images/kids_watershed.jpg

doesn’t ______________. food chain tissues degrade DDT in the environment gets into organisms through the ___________, is stored in __________, and doesn’t ______________. food chain tissues degrade http://www.geocities.com/~greyhawk_1/sh_eagle-9.jpg

→ → BIOLOGICAL MAGNIFICATION ______________________________ = the ____________ of a harmful substance ____________as it passes to organisms at _______________levels in food chain or web. concentration increases higher trophic Plants pick up DDT from water & store it Herbivores eat plants and store some DDT Carnivores eat herbivores and store more DDT → →

Figure 6-16 Biological Magnification of DDT Section 6-3 Magnification of DDT Concentration Fish-Eating Birds 10,000,000 Large Fish 1,000,000 100,000 Small Fish 10,000 Zooplankton 1000 Producers Water 1

The wide spread use of DDT threatened many species… especially fish eating birds like osprey, brown pelican, and bald eagles. DDT causes birds to lay eggs with ___________ shells so eggs would break when sat on. American Bald Eagle was declared endangered in 1967. It has since been reclassified as _____________________ http://image10.webshots.com/11/3/94/67/2146394670011493049pwlCDV_ph.jpg fragile “threatened”

_______________ published the book,_____________ which http://www.kimball.k12.sd.us/Heroes%20Web%20Page/Pictures/Rachel%20Carson.jpg In 1962, American biologist _______________ published the book,_____________ which told of DDT’s harmful effects. The book led to a large public outcry and eventually resulted in DDT being _________ in the United States in the 1970’s The book was one of the important events in the birth of the _________________________. Rachel Carson Silent Spring banned environmental movement

WHAT DOES IT MEAN? REMEMBER! Everything is connected. BIODIVERSITY is a measure of the __________ of an ecosystem. _______ DIVERSITY = BETTER HEALTH MORE Image from: Pearson Education Inc, publishing as Pearson Prentice Hall ©2006

CONSERVING BIODIVERSITY Examples of efforts to keep a species from becoming extinct: ___________________ (raised and protected in zoos until population is stable, then returned to wild Captive breeding http://www.blackfootedferret.org/

CONSERVING BIODIVERSITY Today conservation efforts focus on protecting entire ecosystems not just individual species ______________ = are places that are MOST endangered HOT SPOTS Image from: Pearson Education Inc publishing as Pearson Prentice Hall© 2006

WHAT CAN BE DONE? Urban planning so there is less “ Sprawl” Set aside land for parks/preserves Research to understand species/ecosystem interactions Concentration of $ on HOT SPOTS to maximize results for $ spent http://www.anselm.edu/homepage/jpitocch/genbios/piplosign6403.jpg