AP Environmental Science Review

1. superposition The principle that any given rock layer is probably older than those above it and younger than those below it 2. continental crust Extends from surface of Earth down to 20-30 miles. Continental crust (granite) is less dense then ocean crust (basalt). 3. oceanic crust Extends down from the surface of the Earth to 7 miles. Crust is layered and very uniform. Com- posed of basalt. 4. mantle Contains most of Earth's mass. Composed of iron, magnesium, aluminum, and silicon-oxygen com- pounds 5. core Composed mostly of iron and is so hot that the outer core is molten. The inner core is under such extreme pressure that it remains solid. 6. Continental Drift Theo- ry 1915- Alfred Wegener proposed that all pre- sent-day continents originally formed one land- mass (Pangaea). 7. lithosphere Lithosphere (crust and upper mantle) is divided into massive sections known as plates, which float and move on the asthenosphere. 8. transform boundaries Occur where plates slide PAST each other. 9. San Andreas Fault Found near the western coast of North Ameri- ca. Where the Pacific and North American plates move relative to each other. 10. divergent boundaries Occur where two plates slide APART from each other with the space that was created being filled with molten magma from below. 11. Mid-Atlantic Ridge and Pacific Rise 12. East African Great Rift Valley Examples of oceanic divergent boundaries. Examples of areas of continental divergent bound- aries 13. convergent boundaries Occur where two plates slide TOWARD each oth- er, commonly forming either a subduction zone or orogonic belt. 14. subduction zone Occurs when a denser oceanic plate moves under- neath (subducts) a less-dense continental plate. e.g. Cascade Mountain range (includes Mount Saint Helens) 15. island arc A curved chain of volcanic islands created when two oceanic plates converge. e.g. Japan and the Aleutian Islands in Alaska 16. mountain range Created when two continental plates collide. e.g. Himalayas (Nepal and China) 17. earthquakes Caused by friction and stress buildup from the sliding plates, a common feature along transform boundaries. e.g. Haiti Earthquake 2010 18. seismic waves energy released in the form of vibrations when there is abrupt movement on an existing fault; they move in all directions through the surround rock 19. P waves (Primary waves) 20. S waves (Secondary waves) 21. The severity of an earthquake depends on: Are body waves that travel through the interior of the Earth. Are produced when material moves either vertical- ly or horizontally and travel only within the upper- most layers of Earth. -The amount of potential energy that had been stored -The distance the rock mass moved when the en- ergy was released -How far below the surface the movement occured -The makeup of the rock material 22. liquefaction The process by which an earthquake's violent movement suddenly turns loose soil into liquid mud. 23. tsunami A series of waves created when a body of water is rapidly displaced usually be an earthquake. e.g. TMhoku, Japan Earthquake and Tsunami 2011 (also led to nuclear meltdown at Fukushima) 24. volcano A mountain or hill having a crater or vent through which lava, rock fragments, hot vapor, and gas are being or have been erupted from the earth's crust 25. What do volcano erup- tions do to our atmos- phere? 26. Factors that affect the amount of solar ener- gy at the surface of the Earth: -Release CO2, SO2, HCl -debris and particulates can block sunlight, making a cooler climate -Earth's rotation (once every 24 hours) -tilt of Earth's axis (23.5 degrees) -revolution around the sun (once per year) -closest to sun in winter, furthest in summer 27. O Horizon Surface litter: leaves and partially decomposed organic debris. Thick in deciduous forests, thin in the tundra. 28. A Horizon Topsoil: organic matter (humus), living organisms, inorganic minerals. Topsoil is very thick in grass- lands. 29. E Horizon Zone of leaching: dissolved and suspended mate- rials move downward. In-between A and B horizon. 30. B Horizon Subsoil: tends to be yellowish in color due to the accumulation of Fe, Al, humic compounds, and clay leached down from A and E horizons. Can be rich in nutrients in areas with lots of rainwater. 31. C Horizon Weathered parent material: partially broken-down inorganic minerals 32. parent material The rock and minerals from which the soil derives. Nature of parent rock can be native to the area or transported by wind, water, glaciers, etc. 33. clay -very fine particles -compacts easily -forms large, dense clumps when wet -low permeability to water, thus upper layers bcome waterlogged 34. gravel -coarse particles -consists of rock fragments 35. loam -about equal mixtures of clay, sand, silt, and hu- mus -rich in nutrients -holds water but does not become waterlogged 36. sand -sedimentary material coarser than silt -water flow through too quickly for most crops -good for crops and plants requiring low amounts of water 37. silt -sedimentary material consisting of very fine par- ticles between the size of sand and clay -easily transported by water 38. What color soil is most fertile? a rich dark brown 39. waterlogging saturation of soil with water resulting in a rise of the water table 40. problems of waterlog- ging 41. solutions of waterlog- ging salty water envelops deep roots killing plants; low- ers productivity; eventual destruction of plant life switch to less water-demanding plants in suscepti- ble areas; utilize conservation-tillage farming; plant waterlog-resistant plants; install drainage popes 42. salinization a soil degradation process caused by repeated an- nual application of irrigation water in dry climates, which leads to the gradual accumulation of salts in the upper soil layers 43. problems of saliniza- tion 44. solutions of saliniza- tion stunted crop growth; lower yield; eventual destruc- tion of plant life take land out of production for a while; install drainage pipes; flush soil with freshwater; planted halophytes (salt-loving plants) like barley, cotton, sugar, or wheat 45. desertification occurs when the productive potential of soil, espe- cially on arid or semiarid land, falls by 10% or more because of a combination of prolonged drought and human activities that reduce or degrade top- soil 46. problems of desertifica- tion 47. solutions of desertifica- tion loss of native vegetation; increased wind erosion; salinization; drop in water table; reduced surface water supply reduce overgrazing; reduce deforestation; reduce destructive forms of planting, irrigation, and min- ing; plant trees and grasses to hold soil 48. Soil erosion is the movement of soil components, especially surface litter and topsoil, from one place to another by the actions of wind and water 49. What is most harmful human activity? Agriculture has a greater harmful environmental impact than any other human activity 50. igneous formed by cooling and classified by their silica content. -majority of rocks in Earth's crust are igneous -Intrusive igneous rocks solidify deep under- ground, cool slowly and have large-grained tex- ture. -Extrusive igneous rocks solidify on or near the surface, cool quickly, and have fine-grained smooth texture. -Igneous rocks are broken down by weathering and water transport. e.g. granite and basalt 51. metamorphic formed by intense heat and pressure e.g. diamond, marble asbestos, slate, anthracite coal 52. sedimentary formed by piling and cementing of various materi- als over time in low-lying areas. Fossils form only in sedimentary rock. e.g. conglomerate, breccia, sandstone 53. What seven prima- ry compounds is the Earth's atmosphere composed of? 54. Nitrogen (N2) -nitrogen (78%) -oxygen (21%) -water vapor (0-4%) -carbon dioxide (<<1%) -methane (<<<1%) -nitrous oxide (<<<1%) -ozone (<<<1%) Fundamental nutrient for living organisms. De- posits on Earth through nitrogen fixation and reac- tions involving lightning and subsequent precipita- tion. Returns to the atmosphere through combus- tion of biomass and denitrification. 55. Oxygen (O2) Oxygen molecules are produced through photo- synthesis and are utilized in cellular respiration. 56. Water vapor (H2O) Largest amounts occur near equator, over oceans, and in tropical regions. Areas where atmospher- ic water vapor can be low are polar areas and deserts. -most voluminous greenhouse gas, cannot be added or reduced 57. Carbon dioxide (CO2) Volume of CO2 has increased about 25% in the last 300 years due to the burning of fossil fuels and deforestation. CO2 is produced during cellular respiration and the decay of organic matter. It is a reactant in photosynthesis. CO2 is also a major greenhouse gas. -stays in atmosphere 100 years 58. Methane (CH4) Methane contributes to the greenhouse effect. Since 1750, methane has increased about 150% due to use of fossil fuels, coal mining, landfills, grazers, etc. -stays in atmosphere 12 years 59. Nitrous oxide (NO2) Concentration increasing about 0.3% per year. Sources include burning of fossil fuels, use of fer- tilizers, burning biomass, deforestation, etc. Can come from livestock farts. -stays in atmosphere 120 years 60. Ozone (O3) 97% of ozone is found in the stratosphere (ozone layer). Ozone absorbs UV radiation. Ozone is pro- duced in the production of photochemical smog. CFC's have contributed to ozone layer depletion. Ozone is a pollutant in the troposphere. 61. troposphere -75% of atmosphere's mass is in the troposphere -temperature decreases with altitude -weather occurs in this zone 62. stratosphere -temperature increases with altitude due to ab- sorption of heat by ozone -ozone is produced by UV radiation and lightning -contains the ozone layer 63. mesosphere -temperature decreases with altitude -coldest layer -ice clouds occur here -meteors (shooting stars) burn up in this layer 64. thermosphere (ionos- phere) -temperature increase with height due to gamma rays, X rays, and UV radiation -molecules are converted into ions -causes Northern lights 65. Relationship between altitude, pressure, and temperature within the zones 66. weather is a LOCAL area's short-term temperature, pre- cipitation, humidity, wind speed, cloud cover, and other physical conditions of the lower atmosphere as measured over hours or days -caused by movement of heat energy 67. climate is an area's GENERAL pattern of atmospheric of weather conditions measured over long periods of time ranging from decades to thousands of years 68. radiation the flow of electromagnetic radiation. Method by which Earth receives solar energy. 69. conduction involves transfer of heat through a substance that results from a difference in temperature 70. convection is the primary way energy is transferred from hotter to colder regions in the Earth's atmosphere and determines weather patterns 71. Relationship between cold and hot air Cold air is more dense, hot air is less dense and more spread out 72. albedo is the diffuse reflectivity or reflecting power of a surface 73. specific heat is the amount of heat per unit mass required to raise the temperature by one degree Celsius (wa- ter has a high specific heat) 74. temperature inversion stops atmospheric convection (which is normally present) from happening in the affected area and can lead to the air becoming stiller and murky from the collection of dust and pollutants that are no longer able to be lifted from the surface. Worsens pollution. (COLD air) OVER (WARM air) 75. formation of clouds when rising air, through expansion, cools to the point where some of the water vapor molecules "clump together" faster than they are torn apart by their thermal energy. Some of that (invisible) water vapor condenses to form (visible) cloud droplets or ice crystals. 76. dew point is the temperature below which the water vapor in a volume of humid air condense into liquid water 77. Rain shadow (oro- graphic) effect the loss of moisture from the landscape and the re- sulting semiarid or arid conditions on the leeward side of high mountains -Windward= lush, green, clouds, precipitation, ocean...leedward= deserts, sinking air, dry 78. Coriolis Effect an effect whereby a mass moving in a rotating system experiences a force (the Coriolis force) acting perpendicular to the direction of motion and to the axis of rotation. 79. monsoons a seasonal prevailing wind in the region of South and Southeast Asia, blowing from the southwest between May and September and bringing rain (the wet monsoon), or from the northeast between October and April (the dry monsoon) 80. El Niño and La Niña (Southern Oscillation (ENSO)) large-scale weather phenomenon occurs every few years when prevailing winds in the tropical Pacific Ocean weaken and change direction o Above-average warming of Pacific waters affects populations of marine species by changing the dis- tribution of plant nutrients, hurting fishing industry o Low nutrients, low dissolved oxygen (in South America, but in Australia during La Niña) o Severe flooding, storms, drought, mudslides, $ damage, human health hazards (dehydration, di- arrhea, zoonotic diseases [lyme, Hanta]) 81. Grasshopper effect occurs when volatile air pollutants are transported by evaporation and winds from tropical and tem- perate areas though the atmosphere to the earth's polar areas, where they are deposited. 82. natural sources of pol- lution 83. manmade sources of pollution • dust blown by wind • pollutants from wildfires and volcanic eruptions • VOCs (volatile organic chemicals) released by some plants • Removed naturally by chemical cycles, precipita- tion, and gravity • Industry, cars, electrical plants, coal • Burning of fossil fuels 84. primary pollutants are harmful chemicals emitted directly into the air from natural processes and human activities e.g. SOx, NOx, CO, VOCs, particulates, Lead 85. secondary pollutants formed by some primary pollutants reacting with one another and with the basic component of air to form new harmful chemicals e.g. O3, HNO3 (nitric acid), H2SO4 (sulfuric acid [acid rain]) 86. Ways Air Pollution is In- creased: • Urban buildings can slow wind speed and reduce dilution and removal of pollutants • Hills and mountains can reduce the flow of air in valleys and allow pollutant levels to build up at ground level • High temperatures promote the chemical reac- tions leading to photochemical smog formation (global warming increases smog!) • Emissions of VOCs from certain trees and plants (e.g. oak, sweet gums, poplars, and kudzu) can play a large role in photochemical smog formation • Grasshopper effect • Temperature inversions 87. Industrial smog (gray color) consists mostly of sulfur dioxide, sus- pended droplets of sulfuric acid, and a variety of suspended solid particles 88. Photochemical smog (brown color) is a mixture of primary and sec- ondary pollutants formed under the influence of UV radiation from the sun; formation of this smog begins when exhaust from morning commuter ve- hicles releases large amounts of NO and VOCs into the air over a city • VOCs + NOx + heat + sunlight ’ ground level ozone (03) + other photochemical oxidants + alde- hydes + other secondary pollutants 89. Properties of Water: • strong hydrogen bonds • high specific heat • high boiling point • needs a lot of energy to evaporate • expands when freezes 90. Where is our water? • 70% of Earth's surface is covered by water • oceans hold about 97% of all water • 3% is freshwater • majority of freshwater is stuck in glaciers • 71% is saltwater, 0.024% is readily available freshwater • 60% of the human body is water 91. Lake zonation: • littoral zone • limnetic zone • photic zone • profundal zone • benthic zone (some zones are also applicable to oceans) 92. littoral zone • top layer, near the shore • consists of the shallow sunlit waters to the depth at which rooted plants such as cattails stop grow- ing • most productive zone because of sunlight and nutrients from the surrounding land • high biological diversity 93. limnetic zone • sunlit surface away from shore that extends the depth sunlight penetration • the main photosynthetic body of the lake • produces the food and oxygen that support most of the lake's consumers 94. photic zone • also called euphotic zone • sunlight zone is the depth of the water in a lake or ocean that is exposed to sufficient sunlight for photosynthesis to occur 95. profundal zone • deep open water where it is too dark for photo- synthesis • without sunlight and plants, oxygen levels are low 96. benthic zone • bottom layer • inhabited by decomposers, detritus feeders, and some fish • dead matter falls here 97. oligotrophic lakes lakes that have a small supply of plant nutrients e.g. glaciers, mountains, lakes 98. eutrophic lakes lakes that are well-nourished; have large supply of plants nutrients; are shallow with murky brown or green water 99. mesotrophic no nutrients in lakes 100. hypereutrophic too many nutrients 101. phytoplankton "drifting plants"- primary producers that support aquatic foods webs e.g. many types of algae 102. zooplankton "drifting animals"-primary consumers that feed on phytoplankton and secondary consumers that feed on other zooplankton; daily vertical migration for food e.g. range from single-celled protozoa to large in- vertebrates like jellyfish 103. ultraplankton extremely small photosynthetic bacteria that are responsible for 70% of the primary productivity near the ocean surface 104. nekton strongly swimming consumers such as fish, tur- tles, and whales 105. benthos consists of bottom dwellers such as oysters, clams, worms, lobsters, and crabs 106. limiting factors that determine where a species will live: • temperature • dissolved oxygen content • availability of food • availability of light and nutrients for photosynthe- sis 107. euphotic zone the upper layers where photosynthesis is largely confined because sunlight can penetrate 108. aphotic zone zone where there is no sunlight 109. turbidity when the water is clouded by excessive algal growth or natural/human disturbances like waves, wind, currents, boats, tides, storms, etc. • can prevent sunlight from penetrating the water for photosynthetic plants • can clog fish kills • can prevent fish/organisms from properly hunting prey 110. ocean zonation: • coastal zone • intertidal zone • continental shelf • euphotic zone • bathyal zone • abyssal zone 111. coastal zone • warm temperature, nutrient-rich, extends from shallow water to continental shelf 112. intertidal zone • area of shoreline between low and high tides • organisms must be able to avoid being swept away or crushed by waves; must deal with being immersed in high tides and left dry during low tides; must deal with changing levels of salinity • most intertidal organisms: hold onto something, dig in, or hide in protective shells 113. wetlands (estuaries, swamps, marshes) • water table stands at or near the land surface • soil is either permanently or seasonally saturated • most biologically diverse of all ecosystems • water can be saltwater, freshwater, or brackish • breeding grounds, storm protection, reduce wave impacts, support marine life, stabilize shorelines • productive-high nutrient input from rivers and nearby land and rapid circulation of nutrients • ample sunlight in shallow waters • plant life includes: mangroves, cattails, cypress • animal life includes: birds, mammals, amphib- ians, etc. 114. mangrove forests • reduce the impacts of rising sea levels and more intense storm surges, which may become more powerful with global warming • help maintain water quality through filtration • produce food, habitats, and nursing sites • reduce storm damage • adapted to changing salinity within tides • threatened by rising sea levels, a result of global warming • largest mangrove area is in Indonesia 115. barrier islands • low, narrow, sandy islands that form offshore, parallel to some coastlines • generally have one or more rows of natural sand dunes (protection) 116. economic and ecolog- ical services provided by marine ecosystems: • value of goods and services yearly is about $12 million • oil and natural gas, food, animal/pet food, phar- maceuticals, transportation/harbors, employment • reservoirs of biodiversity • climate moderation (CO2 absorption) • waste treatment • nutrient recycling • reduced storm impact 117. threats to aquatic biodi- versity: • dams and canals fragment natural biodiversity and destroy wildlife • cities and farms add pollutants and excess plant nutrients 118. trawler fishing • drags funnel-shaped nets weighted down with heavy chains and steel plates over ocean bottoms to harvest a few species of bottom fish and shell- fish • crushes organisms, buries them in sediment, exposes them to predators • catches shrimp, cod, flounder, and scallops 119. bycatch the unwanted fish and other marine creatures caught during commercial fishing for a different species 120. purse-seine fishing • used to catch surface-dwelling species by having ships senclose on large schools of fish and throw nets • tuna, mackerel, anchovies, herring 121. longlining • putting out lines up to 80 miles long, hung with thousands of baited hooks, to catch open-ocean fish species • swordfish, tuna, sharks, halibut, cod • also bycatch (hook and kill accidentally) endan- gered sea turtles, dolphins, and seabirds 122. drift-net fishing huge fish are caught by huge drifting nets that can hang as deep as 50 feet below the surface and extend 40 miles long. This method can lead to overfishing of the desired and unwanted species. 123. commercial extinction the decline in the population of a wild species, used as a resource, to a level where it is no longer profitable to harvest the species 124. biological extinction occurs whenever a species of animal or plant life is permanently lost 125. ecosystem approach to protect and sustain whole marine ecosystems for current and future generations instead of focus- ing primarily on protecting individual species 126. maximum sustained yield 127. optimum sustained yield 128. multispecies manage- ment model to project the maximum number of fish that can be harvested annually from a fish stock with- out causing a population drop takes into account interactions among species and provides more room for error takes into account their competitive and preda- tor-prey interactions 129. precautionary principle sharply reducing fish harvests and closing some overfished areas until they recover and until we have more information about what levels of fishing can be sustained 130. Three general patterns of marine biodiversity: • The greatest marine biodiversity occurs in coral reefs, estuaries, and the deep-ocean floor • Biodiversity if higher near coasts than in the open sea because of the great variety of producers and habitats in coastal areas • Biodiversity is higher in the bottom region of the ocean than in the surface region because of the great variety of habitats and food sources on the bottom 131. Hydrologic cycle the movement of water in the seas, in the air, and on land, which is driven by solar energy and gravity 132. groundwater water held underground in the soil or in pores and crevices in rock 133. Zone of saturation spaces in soil and rock are completely filled with water 134. Zone of aeration lies between the earth's surface and the water table; the surface is marked by the presence of vegetation 135. water table top of the groundwater zone; can fall or rise de- pending on weather 136. aquifers • underground caverns and porous layers of sand, gravel, or bedrock through which groundwater flows • most aquifers recharge extremely slowly because urban development prevents water from easily penetrating the ground 137. confined aquifers is bounded above and below by less permeable beds of rock, and its water is confined under pres- sure 138. unconfined aquifers is an aquifer with a permeable water table 139. deep aquifers some of these aquifers hold enough water to sup- port billions of people; water quality is higher than most rivers and lakes; people must experiment to see if salt or fresh 140. artesian well is a confined aquifer containing groundwater under positive pressure 141. natural recharge process in which aquifers are replenished naturally by precipitation that percolates downward through soil and rock 142. lateral recharge process in which aquifers are recharged from the side from nearby rivers and streams 143. spring is any natural situation where water flows to the surface of the Earth from underground; a spring is a site where the aquifer surface meets the ground surface 144. saltwater intrusion movement of saltwater into an aquifer, which may cause contamination 145. cone of depression occurs in an aquifer when groundwater is pumped from a well 146. surface runoff precipitation that does not infiltrate the ground or return to the atmosphere by evaporation 147. reliable surface runoff the amount of surface runoff that we can generally count on as a source of freshwater from year to year 148. watershed or drainage basin the land from which surface water drains into a particular river, lake, wetland, or other body of water • 70% of water is used for agriculture, 20% of water is used for industry, 10% of water is used by humans and cities 149. drought a prolonged period in which precipitation is at least 70% lower and evaporation is higher than normal in an area that is normally not dry • dries out soils, reduces stream flows, decreases tree growth and biomass, lowers net primary pro- ductivity, reduces crop yields, and causes a shift in some biomes towards relatively dry conditions • political/legal conflicts, depression for farmers 150. main factors causing water scarcity: 151. Water Privatization: Pros 152. Water Privatization: Cons 153. Withdrawing Ground- water: Advantages • dry climate, drought, too many people using a normally reliable supply of water, and wasteful use of water • farmers, cities, and car owners are increasingly competing for access to the world's grain and wa- ter supplies, which in turn can degrade some of the natural capital that provides these resources • Private companies have the money and exper- tise to manage water resources better and more efficiently than governments • Some private water management companies have done a good job in the past • Because private companies make money by de- livering water, they have an incentive to sell as much a possible rather than conserving it • Because they have too little money to pay water bills, the poor will continue to be left out • Water should be a public resource • Useful for drinking and irrigation • Available year-round • Exists almost everywhere • Renewable if not overpumped or contaminated • No evaporation losses • Cheaper to extract than most surface waters 154. Withdrawing Ground- water: Disadvantages • Aquifer depletion from overpumping • Sinking of land (subsidence) from overpumping • Aquifers polluted for decades or centuries • Saltwater intrusion into drinking water supplies near coastal areas • Reduced water flows into surface waters • Increased cost & contamination from deeper wells 155. land subsidence withdrawing large amount of water sometimes causes sand and rock in aquifers to collapse, which causes the land above the aquifer to subside or sink 156. sinkholes large craters that form when the roof of an under- ground cavern collapses after being drained of the groundwater that supports it 157. Groundwater Deple- tion: Solutions • Waste less water • Subsidize water conservation • Limit number of wells • Do not grow water-intensive crops in dry areas • Raise price of water to discourage waste • Tax water pumped from wells near surface waters • Set and enforce minimum stream flow levels • Divert surface water in wet years to recharge aquifers 158. dam • a structure built across river to control the river's water flow • ¼ of the world's damn produce about 20% of the world's electricity 159. reservoir 160. Damming the Water- ways: Advantages 161. Damming the Water- ways: Disadvantages an artificial lake created by the river's flow after it is dammed; behind dam • Provides irrigation water above and below dam • Provides water for drinking • Reservoir useful for recreation and fishing • Can produce cheap electricity (hydropower) • Reduces downstream flooding • Capture and store runoff • Flooded land destroys forests or cropland and displaces people • Large losses of water through evaporation • Deprives downstream cropland and estuaries of nutrient-rich silt • Risk of failure and devastating downstream flood- ing • Disrupts migration and spawning of some fish • Sediments build up behind dam in reservoirs • Higher rates of evaporation • Downstream people have less water 162. Water in Saudi Arabia • Saudi Arabia is as water-poor as it is oil-rich, so it gets about 70% of its drinking water at a high cost from the world's largest system for removing salt from seawater, located on its eastern coast • Saudi Arabia has the world's largest number of desalination plants 163. desalination • removes dissolved salts from ocean water of from brackish water in aquifers of lakes for domestic use -High cost and energy footprint -Pumping large volumes of seawater through pipes and using chemicals to sterilize water and keep down algal growth kills many marine organ- isms -Produces large quantities of briny wastewater that contain lots of salt and other minerals...dumping this water into the ocean is bad 164. distillation heating saltwater until it evaporates, leaving be- hind salts in solid form and condensing freshwater 165. reverse osmosis (mi- crofiltration): uses high pressure to force saltwater through a membrane filter with pores small enough to re- move the salt 166. flood irrigation water is distributed over the soil surface by gravity; the most common form of irrigation and most inef- ficient; loses 40% of water 167. center-pivot, low-pres- sure sprinkler 168. low-energy, precision application (LEPA) sprinklers uses pumps to spray water on a crop; results in a series of circular irrigated areas; 80% of water reaches crops another form of center-pivot irrigation, put 90-95% of the water where crops need it 169. drip or trickle irrigation (micro irrigation) 170. Reducing Irrigation Wa- ter Waste: Solutions method that saves water and fertilizer by allowing water to drip slowly to the roots of plants, either onto the soil surface or directly onto the root zone, through a network of valves, pipes, tubing, and emitters; MOST efficient method because least evaporation; 90-95% of water reaches the crops • Line canals bringing water to irrigation ditches • Irrigate at night to reduce evaporation • Monitor soil moisture to add water only when necessary • Grow several crops on each plot of land (polycul- ture) • Encourage organic farming • Avoid growing water-thirsty crops in dry areas • Irrigate with treated urban wastewater • Import water-intensive crops and meat 171. xeriscaping uses drip-irrigation and copies nature by replacing green lawns with plants that need little water; re- duces water use by 30-85% and sharply reduces need for labor, fertilizers, and fuel 172. rainwater harvesting involves running pipes from rooftops and digging channels to catch rainwater 173. Reducing wastewater: • Redesign manufacturing processes to use less water • Recycle water in industry • Fix water leaks, use water meters, raise water prices • Use drip irrigation • Use waterless composting toilers • Require water conservation in water-short cities • Purify and reuse water for houses, offices, build- ings 174. Sustainable water use: • Waste less water and subsidize water conserva- tion • Do not deplete aquifers • Preserve water quality • Protect forests, wetlands, mountain glaciers, wa- tersheds, and other natural systems • Get agreements among regions and countries sharing surface water resources • Raise water prices • Slow population growth 175. floodplain • is an area of land adjacent to a stream or river that stretches from the banks of its channel to the base of the enclosing valley walls and experiences flooding during periods of high discharge • Pros: amble water for irrigation; availability of nearby rivers for transportation; flat land suitable for crops; include highly productive wetlands; help to provide natural flood and erosion control; main- tain high water quality; recharge groundwater; fer- tile soil • Cons: floods kill people; damage to property 176. Reducing Flood Dam- age: Solutions 177. biodiversity • Preserve forests on watersheds • Preserve and restore wetlands in floodplains • Tax development on floodplains • Use floodplains primarily for recharging aquifers, sustainable agriculture, and forestry • Straighten and deepen streams (channelization) • Build levees or floodwalls along streams • Build dams is the variety of the earth's species, the genes they contain, the ecosystems in which they live, and the ecosystem processes that sustain all life 178. functional diversity the variety of processes such as matter cycling and energy flow taking place within ecosystems 179. ecology the study of how organisms interact with their living (biotic) environment 180. biological evolution the process whereby earth's life changes over time through changes in the genes of populations 181. fossil record is incomplete because of decomposers, nonideal conditions, natural disasters, asteroids or meteors, etc. 182. natural selection occurs when some individuals of a population have genetically based traits that enhance their ability to survive and reproduce 183. differential reproduc- tion enables individuals with the trait to leave more off- spring than other members of the population leave (a trait must do this and MUST BE HERITABLE for natural selection to occur) 184. genetic resistance the ability of one or more organisms in a popula- tion to tolerate a chemical designed to kill it (e.g. bacteria with regard to hand sanitizer) 185. Geological processes that affect natural se- lection: • Tectonic plates- locations of continents and oceanic basins greatly influence the earth's cli- mate and movement of continents spread animals to new places (new resources) • Earthquakes- disruptions in earth's crust that can isolate species • Volcanic eruptions- can reduce or wipe out pop- ulations • Natural catastrophes 186. speciation process when two species arise from one 187. geographic isolation occurs when different groups of the same popula- tion of a species become physically isolated form one another for longs period 188. reproductive isolation mutation and change by natural selection operate independently in the gene pools of geographically isolated population 189. background extinction species disappearing at a low rate throughout his- tory 190. species diversity the number of different species a community con- tains (species richness) combined with the rela- tive abundance of individuals within each of those species (species evenness) 191. endemic species species that are found in only one area; vulnerable to extinction 192. generalist species broad niches (e.g. deer) 193. specialist species narrow niches; more vulnerable (e.g. panda bear) 194. indicator species species that provide early warnings of damage to a community or an ecosystem (e.g. amphibians [because their breath through skin]) 195. keystone species have a large effect on the types and abundance of other species in an ecosystem (e.g. shark, bum- blebee, sea otters in kelp forests) 196. foundation species role in shaping communities by creating and en- hancing their habitats in way that benefit other species (e.g. kelp forest) 197. biomass the amount of living material, or the amount of or- ganic material contained in living organisms, both as live and dead material, as in the leaves (live) and stem wood (dead) of trees 198. productivity the rate of production; that is, the amount of in- crease in organic matter per unit of time (for ex- ample, grams per meter squared per year) 199. ecological succession the process of the development of an ecological community or ecosystem, usually viewed as a se- ries of stages: early, middle, late, mature (or cli- max), and sometimes post-climax 200. primary succession the gradual establishment of biocommunities in a lifeless area that has NO soil or sediment 201. early succession- al species/pioneer species species that occur only or primarily during early stages of succession. With vegetation, these are typically rapidly growing and short-lived with high reproductive rates. 202. secondary succession a series of communities or ecosystems with differ- ent species that evolve where there's soil 203. late successional species 204. Early, Middle, and Late Successionary Stages: species that occur only or primarily in, or are dom- inant in late stages in succession. With plants, these are typically slower growing and long-lived species. • Early: biomass and biological diversity increase organic matter. • Middle: biomass increases; diversity remains in- creases, organic matter increases. • Late: biomass decreases, diversity decreases, and organic matter decreases. 205. island biogeography • proposes that the number of species found on an undisturbed island is determined by immigration and extinction • Distance from mainland: closer island, higher immigration • Size of island: small island have fewer sepcies than large islands and smaller target for immi- gration...higher extinction because less resources and diversity 206. interspecific competi- tion 207. competitive exclusion principle occurs when members of two or more species in- teract to gain access to the same limited resources (e.g. food, light, or space) no two species can occupy exactly the same eco- logical niche for very long (e.g. cheetahs and lions) 208. predation occurs when a member of one species (the preda- tor) feeds directly on all or part of a member of another species 209. Techniques to avoid predation: camouflage, chemical warfare, warning coloration, mimicry 210. coevolution evolution in which two or more species interact and exert selective pressures on each other that can lead each species to undergo adaptations e.g. bats and insects 211. resource partitioning occurs when species competing for similar scarce resources evolve specialized traits that allow them to use shared resources at different times, in dif- ferent ways, or in different places 212. population dynamics 213. Patterns of population distribution: the study of how characteristics (distribution, numbers, age, structure, density) of populations change in response to change in environmen- tal conditions (temperature, resource availability, presence of diseases) • Clumping- beneficial because 1. Species tend to cluster where resources are available, 2. Mov- ing in groups increases chances of encountering resources, 2. Living in groups protects some ani- mals from predation, 4. Hunting in packs increases chance of catching prey • Uniform dispersion • Random dispersion 214. biotic potential • is the maximum reproductive capacity of a popu- lation if resources are unlimited • Large animals (e.g. elephants), low potential • small animals (e.g. bacteria), high potential 215. Intrinsic rate of in- crease (r) 216. environmental resis- tance • rate at which a population would grow if it had unlimited resources • High rate= reproduces early, short generation times, reproduces many times, many offspring the combination of all factors that act to limit the growth of a population (e.g. of limiting factors: light, water, space, nutrients, amount of water) 217. carrying capacity (K) maximum population of a given species that a particular habitat can sustain indefinitely without being degraded 218. exponential growth (J curve) 219. logistic growth (S curve) • growth that increases at a constant rate per unit of time • starts slowly, but accelerates as population in- creases rapid population growth, followed by a steady de- crease in population growth until the population size levels off 220. genetic drift random changes in gene frequencies in a popula- tion that can lead to unequal reproductive success, some individuals will breed more, thus their genes will dominate the gene pool 221. inbreeding occurs when individuals in a small population mate with one another 222. minimum viable popu- lation size long-term survival species...the number of individ- uals need for long-term survival 223. founder effect occurs when only a few individuals in a population colonize a new habitat that is geographically iso- lated (e.g. finches on Galapagos Islands) 224. demographic bottle- neck effect 225. density-dependent fac- tors: occurs when only a few individuals in a population survive catastrophic events, and then the popula- tion lacks genetic diversity infectious disease, parasitism, predation, competi- tion 226. density-independent factors: 227. r and k selected species: habitat destruction, pollution, temperature change -