AGRICULTURE and HUMAN IMPACT on the BIOSPHERE Chapter 6
HUMAN POPULATION You are here http://www.learner.org/jnorth/spring2002/species/spring/Update041902.html#Humankind
WORLD POPULATION Current world population is just over _____________ https://mycupofcareisempty.files.wordpress.com/2011/11/overpopulation.gif World clock Current world population is just over _____________ Estimates predict it will reach 9 billion by 2050 http://www.peopleandplanet.net/
Does this look familiar? What is the Earth’s carrying capacity?
SUSTAINABILITY How can we grow enough food for all the people on the planet without destroying the environment? http://www.enjoy.org/hstech/HungerSite02/america/FordSchwartz/ http://ejcw.org/wp-content/uploads/2015/08/640x360-ag-runoff.jpg
Importance of Agriculture By middle of 20th century, despite agricultural advances there were ________________in many parts of the world. Governments and scientists began a major effort to ___________ food production http://www.enjoy.org/hstech/HungerSite02/america/FordSchwartz/
__________ REVOLUTION New plant ________ had higher yield & resisted pests 2. Modern farming__________ allowed planting larger areas 3. Chemical ___________ & ___________ boosted crop production and controlled pests http://interactive.usask.ca/ski/media/stills/agriculture/crops/t_plant-breeder.jpg http://www.wfbf.com/media_center/photo_gallery/Soybean%20combine.jpg
HOW DO WE GROW MORE FOOD? Large fields are planted with a single variety year after year = ____________ http://imagesource.allposters.com/images/NGSPOD04/107870.jpg
Allows farmers to grow large quantities of food BUT . . . MONOCULTURE Allows farmers to grow large quantities of food BUT . . . http://agronomyday.cropsci.illinois.edu/2003/csrec-welcome/aeriel-view.jpg
But . . . HAS HUGE IMPACT ON ECOSYSTEMS __________ increase yield BUT . . . RUNOFF can cause algal blooms and ____________ http://www.biology-blog.com/images/blogs/10-2007/fertilizer-15101.gif
But . . . HAS HUGE IMPACT ON ECOSYSTEMS ________ kill insects that damage crops BUT . . . they kill ________ insects too Bees Hand pollination http://cms1.good.is/posts/full_1289265646pesticides.jpg http://www.fllt.org/content/uploads/2014/12/1-Honey-Bee-001.jpg
_____ was first modern insecticide Example: _____ was first modern insecticide It was cheap, stayed active for long time, and killed many different insects Used to control agriculture pests and disease carrying _______________ http://www.michigan.gov/images/mosquito_65147_7.jpg
http://www. ci. cypress. ca http://www.ci.cypress.ca.us/public_works/stormwater_images/kids_watershed.jpg When DDT was sprayed, runoff carried it into rivers and streams in LOW concentrations. http://www.geocities.com/~greyhawk_1/sh_eagle-9.jpg DDT then passes into organisms through the ___________, is stored in _______, and doesn’t ___________. http://www.geocities.com/~greyhawk_1/sh_eagle-9.jpg
→ → ______________________________ = the ____________ of a harmful substance ____________as it passes to organisms at _______________levels in food chain or web. Plants pick up DDT from water & store it Herbivores eat plants and store some DDT Carnivores eat herbivores and store more DDT → →
American Bald Eagle was declared endangered in 1967. It has since been 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
told of DDT’s harmful effects. 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 _________________________.
But . . . HAS HUGE IMPACT ON ECOSYSTEMS Wearing away of topsoil = _________ is caused by plowing land and removing plant roots http://coweeta.ecology.uga.edu/coweeta_photographs/erosion.htm
But . . . HAS HUGE IMPACT ON ECOSYSTEMS http://i.telegraph.co.uk/multimedia/archive/02075/COW_2075448c.jpg ________ from feedlots and fields can contaminate surface and ground water ____________ happens to clear trees for beef farms Raising cows uses lots of ______ and releases ________ into the atmosphere increasing climate change.
Impact of Agriculture ______________ = changing of fertile land in dry climates into desert areas caused by farming, overgrazing, and drought http://4.bp.blogspot.com/-Pao2Oe2O_W0/U5F99ppqiII/AAAAAAAAAlY/rlbQFoR4b2c/s1600/invisible+fences+1.jpg
But . . . HAS HUGE IMPACT ON ECOSYSTEMS Many Midwest states rely on the _________ aquifer for their water needs. We are using water faster than the ______cycle can replace it. Evidence indicates this aquifer may _________ within 20-40 years. http://www.suu.edu/faculty/bowman/Econ1740/HeilbronerZinn/ogallala_aquifer_map_pic_2.gif
FRESH WATER RESOURCES Americans use BILLIONS of gallons of freshwater daily for ________, ________ and ___________________ drinking washing watering crops http://www.thesolutionsite.com/lesson/4601/freshwater.jpg
HOW DO WE HELP? Modern_________ is changing how farmers farm and lessening the impact on the environment. EX: __________ imaging _____ technology enable farmers to only apply chemicals where__________
HOW DO WE FIX IT? ________ keeps plant residue in fields Reduces __________ and protects ecosystems from runoff http://cbarc.aes.oregonstate.edu/images/no-till.jpg
HOW DO WE FIX IT? Planting legumes, alfalfa, grasses and other __________ keeps plants on soil between food crops - reduces __________ and protects ecosystems from runoff - reduces ______ - reduces need for fertilizer
HOW DO WE FIX IT? ______________ alternates what is crops are planted each year. - helps control ________ without pesticides - alternating with __________ replenishes soil nutrients without fertilizer
HOW DO WE FIX IT? ________________ = managing graze periods and herd densities - improves nutrient cycling - retains water - ________ desertification http://www.uaex.edu/farm-ranch/animals-forages/images/006.jpg
HOW DO WE FIX IT? __________ pest control uses natural predators like insects or spiders to kill insects instead of chemical pesticides http://static.dudeiwantthat.com/img/outdoors/garden/1500-live-ladybugs-11829.jpg
HOW DO WE FIX IT? _______________ = on hilly areas, plowing is done across the hill rather than straight up and down - prevents soil _______ from runoff http://images.slideplayer.com/24/7068759/slides/slide_25.jpg
HOW DO WE HELP ? Water conservation Protect wetlands and forests Water treatment plants Clean water regulations hhttp://www.romanviii.co.uk/bp/nhpage.asp?pcat=about_us
WAYS TO CONSERVE WATER http://www.watersavingtips.org/images/saving_1.jpg
WHAT CAN YOU DO? - Eat _____ meat - Don’t ______ food ~ 1/3 of all food produced worldwide, ($1 trillion) gets lost or wasted ~ US avg: 20 lbs/person/month wasted Per capita/year Food waste http://teacherweb.com/CA/NogalesHighSchool/mespinoza/fig50EnergyPyramid.jpg http://languagesoftheworld.info/wp-content/uploads/2014/10/Meat-consumption-World.jpg
WHAT CAN YOU DO? Be aware of ___________ water Water the is used to produce products that we don’t know or don’t think about The PRODUCTION OF: 1 kg wheat costs 1,300 L water 1 kg rice costs 3,400 L water 1 kg eggs costs 3,300 L water 1 kg beef costs 15,000 L water 1 cotton shirt costs 2,500 L water 1000 g of blue jeans costs 10,850 liters water 1 ton passenger car costs 400,000 liters of water Building a house uses about 6 million liters of water Change the way you think Change the way you think about your laptop