Lecture 13Outline of Last Lecture I. Water Types II. Water Input III. Water Quality IV. Water and Animal Abundance V. Water and Populations VI. Behavioral Responses VII. Disturbances VIII. Soils Outline of Current Lecture II. History III. Industrial Agriculture a. Modern Farming Practices b. Impacts on Wildlife IV. Farmland Restoration V. Conservation Reserve Program Current Lecture What might be the effects on wildlife abundance and diversity if farmlands were “abandoned”? !History Agriculture greatest factor affecting wildlife (not forestry or overhunting) - because it has essentially removed habitat and will be with humans for a long time - given this, how can we conserve wildlife in the face of agriculture? !Stone walls in the Northeast? NRC 261 1st Edition!!!These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute. !Edited with the trial version of Foxit Advanced PDF EditorTo remove this notice, visit:www.foxitsoftware.com/shopping! - it wasn’t always a forested area — they were stone walls in pastures in the 19th century - would have to pick rocks out of the field — so use those rocks to build walls to mark boundaries and keep animals in desired grazing areas ! Monocultures - lots of agriculture of the same kinds of species over a large stretch of land - out in the Midwest there are miles upon miles of agricultural land — some plowed (places with good water) ! Center-pivot irrigation — places with poor water use this kind of irrigation to be like artificial rain - creates circles on the ground - drill down to the middle of an area that irrigates the crops that are around it, the water source pivots in a circle !American prairies — what used to be there before farmland -in east it was deciduous forest -tundra and boreal forest in north -east of rockies to Mississippi river was tall grass prairie land (shorter grass prairie in the west because of less moisture) -sea of grass !Land rush and sod houses -no trees around, can’t build wood houses -in american prairie, cut down into the soil and picked pieces of sod (like roots of tall grass growing there) -made houses with these bricks of sod on top of nutrient rich loam soil that was a very nutrient resource for farming from thousands of years of plant matter decay -idea to use the skills you had as a farmer where you could actually grow things and have enough nutrients/water and produce crops at a much higher efficiency — why going west was so important -with homestead acts to encourage people to go farm, US was interested in expanding the potential of people who contribute to the economy by growing crops !Changes on family farms -most common type of farm in 1800’s and early 1900’s -limited in the type of equipment they had -lots of farms but because of density of people, there were lots of patches of forest still existing, so family farms were mixture of farmland and trees/natural vegetation -changed in WWII (coming on the tail of Great Depression and Dust Bowl) -US huge expense to wage war (germany and japan) -large scale increased need for food — millions of people leaving to fight and couldn’t be responsible for this!-had to put a lot of mechanical productions into war machines — however created an explosion in the mechanization of farming (not just horse and plows but now tractors etc.) that allowed for the needed amount of food to be harvested from the land -more farmland was developed — major landscape changes because increase in need for food and increase in way food was produced ! breeding birds in Illinois - particular plot of land (4 sq miles) someone in 1909 counted # of breeding bird species there were: 18 - post WWII there were only 9 species there - native species disappeared (like prairie chickens), some increases in birds (english house sparrows and european starlings for example) - those that stayed were generalists — the number of native species breeding declined so much because of changes (they were specialized to only a specific kind of habitat) land use - percentage of agricultural grassland went from over 1/2 to only 12% - corn & sobeans went from 1/4 of land to 3/4 of land - larger fields of row crops - borders of field that had vegetation with them went from 70 km down to 10 km in length (got rid of most of the hedgerows) wildlife - there were 130 places that were open grassland display places before WWII, and there were none afterwards - density of quail declined by 80% - rabbit index went from 5.1 to .2 (97% decline) - all of this happened because lots of places that were wildlife habitat disappeared, and so did the species that lived there (no species lived in row crops) !Industrial Agriculture (how do you feed 10 billion people?) Modern farming practices Mechanization of equipment — big machines doing work ! Hybrid grains - everything is genetically modified, but we’ve done it in ways that we believed was in the realm of nature - an attempt to try and produce more food on the same amount of land area ! Fertilizers — used lots more and tried to do it efficiently !! Pesticides ! Larger farms/fewer farms ! Draining and clearing of wetlands - bogs/marshes that we didn’t see as productive in any sort of way so they cleared them to plant corn (for exmaple) !!Specific types of impacts on wildlife ! Direct loss of places where animals could live - removal of cover - draining and filling of wetlands — complete changes in the kinds of landscapes that were there Pesticide Use - didn’t think about consequences up the food chain Fertilizer use - increased use - when there’s rain, lots run off of farmland and into water and change the environment in those ecosystems Clearing of hedgerows and woodlots - forest being fragmented (broken up) = wildlife fragmentation - all the connections between plots of land was gotten rid of - reduced diversity between plant and animal diversity (reduce habitat diversity) Fall plowing - wanted to turn over soil so the crop remains that were there could put nutrients back into the soil and so for the next season the soil was ready to have crops - total loss of winter cover and food (stubble usually at the top can provide cover as well as fragments of food to store)