APES Unit 5 STUDENT PDF

UNIT 5: LAND AND WATER USE  Learning Objectives ◦ Unit 5 Enduring Understanding ◦ 5.9: Impacts of Mining ◦ When humans use natural resources, they alter natural systems. ◦ Describe natur...

UNIT 5: LAND AND WATER USE  Learning Objectives ◦ Unit 5 Enduring Understanding ◦ 5.9: Impacts of Mining ◦ When humans use natural resources, they alter natural systems. ◦ Describe natural resource extraction through mining. ◦ Humans can mitigate their impact on land and water resources through sustainable use. ◦ Describe ecological and economic impacts of natural resource extraction through mining. ◦ 5.1: The Tragedy of the Commons ◦ 5.10: Impacts of Urbanization ◦ Explain the concept of the tragedy of the commons. ◦ Describe the effects of urbanization on the environment. ◦ 5.2: Clearcutting ◦ 5.11: Ecological Footprints ◦ Describe the effect of clearcutting on forests. ◦ Explain the variables measured in an ecological footprint. ◦ 5.3: The Green Revolution ◦ 5.12: Introduction to Sustainability ◦ Describe changes in agricultural practices. ◦ Explain the concept of sustainability. ◦ 5.4: Impact of Agricultural Practices ◦ 5.13: Methods to Reduce Urban Runoff ◦ Describe agricultural practices that cause environmental damage. ◦ Describe methods for mitigating problems related to urban runoff. ◦ 5.5: Irrigation Methods ◦ 5.14: Integrated Pest Management ◦ Describe different methods of irrigation. ◦ Describe integrated pest management. ◦ Describe the benefits and drawbacks of different methods of irrigation. ◦ Describe the benefits and drawbacks of integrated pest management (IPM). ◦ 5.6: Pest Control Methods ◦ 5.15: Sustainable Agriculture ◦ Describe the benefits and drawbacks of different methods of pest control. ◦ Describe sustainable agricultural and food production practices. ◦ 5.7: Meat Production Methods ◦ 5.16: Aquaculture ◦ Identify different methods of meat production. ◦ Describe the benefits and drawbacks of aquaculture. ◦ Describe the benefits and drawbacks of different methods of meat production. ◦ 5.17: Sustainable Forestry ◦ 5.8: Impacts of Overfishing ◦ Describe methods for mitigating human impact on forests. ◦ Describe causes of and problems related to overfishing.  Fishlab 5.1: Tragedy of the Commons ◦ Individuals will use shared resources in their own self interest rather than in keeping with the common good, thereby depleting the resources ◦ Examples: overgrazing, overfishing, water and air pollution, overuse of groundwater ◦ When no one owns the resource, no one directly suffers the negative consequences of depleting, degrading, or overusing it ◦ People assume others will overuse the resource if they don’t So how do we mitigate this? ◦ Private land ownership (individual or government) ◦ Fees or taxes for use (permit system for grazing or logging) ◦ Taxes, fines, criminal charges for pollution of shared air/soil/water resources  4.6: Watersheds ◦ All of the land that drains into a specific body of water (river, lake, bay, etc.) ◦ Vegetation, soil composition, and slope all play a large role in how watersheds drain water soil ◦ More vegetation= more infiltrationin more and groundwater recharge ◦ Greater slope= faster velocity of runoff and more soil erosion ◦ Soil permeability determines runoff vs infiltration rates ifagwatershed off ◦ Human activities on it oesinto r run soiloJust impact water quality, agriculture, clearcutting, urbanization, dams, mining  accesabletohumans litteratyintheground Aquifers and Groundwater ◦ Groundwater: H2O stored in pore space of permeable rock and sediments ◦ Aquifers are useable groundwater deposits for humans ◦ Replenished by groundwater re-charge (rain percolates down through soil into aquifer) The Race to Feed the World The industrialization of agriculture has boosted worldwide production of food and fiber immensely, but has also brought increased pollution and resource depletion.  Agriculture Agriculture is the practice of raising crops and livestock for human use and consumption. Most of our food and fiber is obtained from cropland, land used to raise crops for human use. Rangeland, or pasture, is land used for grazing livestock. Growing crops and raising animals require inputs of resources—soil, sunlight, water, nutrients, and pollinators.createswast Agriculture has changed over time 10,000 years ago, many cultures began to domesticate and raise animals and plants for food, which enabled the development of cities, culture, and organized government Traditional agriculture is known as subsistence agriculture, where each family grows crops for themselves, family relies on animal and human labor to plant and harvest crops growingenoughfoodfor your familyonlynoprofit In highly developed countries, subsistence agriculture has largely been left behind and replaced by agribusinesses Today, 38% of land on Earth is used to produce food and fiber. 5.3-5.6: The Green Revolution The Green Revolution introduced new technologies, crop varieties, and farming practices to the developed world. Started a shift of new age practices in order to increase food production, with both positive and negative results Decreased world hunger and increased earth’s carrying capacity Increased soil erosion, biodiversity loss, ground and surface water contamination, and more Was introduced in the 1940’s but really took hold in the 1960’s 6 main aspects of The Green Revolution 1. Mechanization 2. Monocultures 3. GMOs 4. Fertilization 5. Irrigation 6. Pesticides  Mechanization ◦ Increased use of tractors for plowing and tilling fields, and combines for harvesting led to increased yield and profits Pros Cons Machinery does not have the Fossil fuel use (extraction, drawbacks of living labor combustion, reliance upon) Can be specialized and updated Soil compaction Easy to use Efficiency leads to higher yields and profits Monocultures ◦ Growing one single species (corn, wheat, soy) of crop in a field Pros Cons Easy to plant Loss of habitat and Easy to maintain biodiversity Easy to harvest Loss of ancestral varieties All plants need the same Increased possibility of fertilizer, have the same pests, catastrophic event require the same watering Increases soil erosion schedule, etc.  GMOs ◦ A GMO, or genetically modified organism, is a plant, animal, microorganism or other organism whose genetic makeup has been modified in a laboratory using genetic engineering or transgenic technology. Pros Cons Greater yield Safety for human (disease/drought/faster consumption??? growth) Effects on biodiversity Greater food quality Regulation of genetically Reductions in pesticide use modified organisms Reduction of world hunger by increased food production Increased profits GMO Examples  Fertilizers ◦ Shift from organic fertilizers (like manure and compost) to synthetic fertilizers (man made ammonium (Haber Bosch Process), nitrate, and phosphate) Pros Cons Contains measurable and customizable Water soluble runoff levels of nitrogen, phosphorous, and Often overused potassium Does nothing to improve soil structure Easy to transport Disrupts nitrogen cycle Timed release Can cause eutrophication Easily and quickly dispersed No smell Ensure higher yield  Irrigation ◦ Drawing water from the ground or nearby surface waters and distributing it onto fields to increase plant growth Pros Cons Customizable application Depletion of freshwater resources Maximizes yield by maximizing Associated environmental effects growth potential (waterlogging, salinization) Makes agriculture possible in parts Accessible options are typically the of the world where it is naturally least efficient too dry Irrigation and Water Consumption ◦ Industrial: power plants, metal/plastic manufacturing ◦ Municipal: households (toilet, shower, drinking water) ◦ Agriculture: water for livestock, irrigation water for crops ◦ There are four main irrigation strategies and each consume and waste different amounts of water 1. Furrow irrigation 2. Flood irrigation 3. Spray irrigation 4. Drip irrigation Furrow irrigation A trench or furrow that is flooded with water Least efficient- 35% of water lost to evaporation Pros: low investment, high sediment water can be used, allows for some precision of application Cons: ineffective in sandy soil, difficult to apply in small amounts, soil erosion Flood irrigation A body of water is diverted into a field and it is flooded Pros: easy, inexpensive, no mechanization required Cons: requires nearby water, not for all plant types, land must be graded, levees needed, 20% of water used is lost to evaporation, can lead to waterlogging and salinization ○ Waterlogging: A form of soil degradation that occurs when soil remains underwater for prolonged periods. ○ Salinization: soil saltinthe toomuch A form of soil degradation that occurs when the small amount of salts in irrigation water becomes highly concentrated on the soil surface through evaporation. Spray irrigation most common Uses pumps to pump out water to spray directly onto plants ◦ Pros: precision application, supplements can be added, efficient, less than 25% of water lost to evaporation, can be programmed to run at certain times of the day/year ◦ Cons: larger upfront cost than flood and furrow irrigation, can include machinery that runs with electricity or fossil fuels, nozzles can clog, pivot system can wear ruts into soil Drip irrigation Pipes that have pores in them that are buried underground and sweat water directly onto the roots Pros: very low evaporation (5%), reduces nutrient leaching, no land gradient needed Cons: very expensive, clogs easily, requires mechanization, placement makes any other processes difficult Irrigation effects Aquifers can be severely depleted if overused for agricultural irrigation Ogallala Aquifer in the Central US Pesticides ◦ Pesticide A substance, either natural or synthetic, that kills or controls organisms that people consider pests. ◦ Insecticide A pesticide that targets species of insects and other invertebrates that consume crops. ◦ Herbicide A pesticide that targets plant species that compete with crops. Pros Cons Can be customized Possible extermination of nontarget Mass produced species Easily shipped and stored Persistence (they do not break down, Easily and quickly dispersed their toxicity can last a long time) Ensure higher yield Possible human health effects Contamination of ground water Evolution of pesticide resistant pests, creates a pesticide treadmill Pesticides do not cause eutrophication If there is pesticide runoff, it kills nontarget species where it is carried DDT and Atrazine The heavy use of chemical pesticides can cause harm to the environment Herbicide Atrazine is linked to endocrine disruption in frogs DDT causes thinning of eggshells  Pesticide treadmill Chemical pesticides tend to become less effective in time as pests evolve resistance to them. Most pests occur in huge numbers, so it is likely that a few of them have genes that detoxify or metabolize a given pesticide. Individuals with the gene will survive and reproduce at greater rates, creating a new generation with a much higher rate of carrying the gene. Eventually the pesticide becomes ineffective and must be replaced by a new one. 5.4: Impacts of Agricultural Practices ◦ Aside from the pros and cons of practicing advanced agriculture, there are other practices that can cause damage to the environment, including slash and burn agriculture and tilling  Slash and Burn Agriculture ◦ Farming technique found in developing countries ◦ Cutting down trees and vegetation and burning to clear land for agriculture and return nutrients in plants to soil to be used again ◦ Typically tropical rainforest in low nutrient soil ◦ Subsistence farmers ◦ Ash used as fertilizer ◦ Unsustainable ◦ Nutrients provided by ash are quickly used up ◦ Forced to cut down new plot of land for crops  Tilling Tilling- prepares the soil for planting seeds by mixing and breaking up soil When you have bare soil, soil erosion and evaporation can occur Can lead to eutrophication and a need to add fertilizer Turned soil impacts soil structure Turned soil can release sequestered carbon in the form of CO2 Mechanized farming equipment is heavy and leads to compacted soil. They increase emissions and require fossil fuels. 5.7: Meat Production Methods As global wealth and commerce have increased, so have the production and consumption of meat, milk, eggs, and other animal products. Meat production has grown more than fivefold since 1950, and per capita meat consumption has doubled Concentrated Animal Feeding Operations (CAFOs) ◦ Used as a way to quickly get livestock ready for slaughter Pros Cons Less time to produce meat Less expensive, cost to consumers low Crowded and requires antibiotics Given growth hormones to speed production Animals fed grains instead of grass Generate large amounts of organic waste, which can contaminate ground and surface water Free Range Grazing Pros Cons Allows animals to graze on grass entire lifecycle Requires large areas of land Tends to be antibiotic and hormone free Meat produced is more expensive to consumers Organic waste can act as fertilizer Overgrazing can be a concern Animals can graze on land too dry for most crop growth  Overgrazing ◦ Overgrazing exposes soil and makes it vulnerable to erosion. ◦ In a positive-feedback loop, soil erosion makes it more difficult for native plants to grow, perpetuating the problem. ◦ Too many animals grazing an area of land can remove all the vegetation (grass) and compact the soil which leads to topsoil erosion and low water holding capacity ◦ Can cause desertification- degradation of low precipitation regions toward being increasingly arid until they become deserts Effects of Consuming Less Meat ◦ Producing meat for humans to eat is far less efficient than producing plants in terms of energy, land, and water use ◦ Land: all of the room animals take up on land and all of the effects associated with that PLUS ◦ Water: all of the water for the crops that the animals eat PLUS the water the animals themselves drink ◦ Energy: all the energy needed to plant, grow, and harvest plants to feed to animals (10% rule) PLUS ◦ The energy needed to bring water and food to the animals, the energy needed to house the animals, the energy needed to slaughter and package the animals, and the energy to transport and store the meat ◦ Overall: ◦ Reduce CO2, methane, and N2O emissions ◦ Conserve water ◦ Reduce the use of antibiotics and growth hormones ◦ Improve topsoil 5.8: Impacts of Overfishing ◦ Of all the human impacts on the ocean, overfishing may be the most pressing, as may fish stocks have been severely depleted ◦ About 60% of the world’s marine fisheries are fully exploited, meaning we cannot harvest them further without depleting them ◦ Industrialized fishing facilitates overharvesting ◦ Technology advances in the 20th century along with massive ships brought commercial fishing to unimagined levels of harvesting and initiated fishery collapses we are observing today ◦ Overfishing has led to the extreme scarcity of some fish species, which can lessen biodiversity in aquatic systems and harm people who depend of fishing for food and commerce Industrialized fishing methods Purse Net/Purse Sein essentially a giant purse with two drawstrings on it, they find schools of fish using sonar, deploy the net and close it up Drift Nets/ Gill Nets miles long nets that can be set at varying depths behind a ship. As fish swim by, their gills and appendages get caught Longline an extremely long line with evenly spaced hooks help up by buoys that is dragged behind a ship. Trawling involves dragging a cone shaped net through the water or along the bottom of the sea floor. Sonar used to track schools of fish. It’s a very effective tool, especially with purse sein netting. Fishing Down the Food Web 5.9: Impacts of Mining Mining and refining Mining = obtaining minerals from the ground Gold Diamonds Phosphorous bearing rock Gravel Coal Refining = industrial process that removes impurities from a substance When things are mines they typically are not pure substances, they contain impurities. This is called ore Ore runningoutharderto find There is high quality and low quality ore When you have high quality ore it doesn’t take a lot to purify it Low quality ore requires a lot of energy, fuel, and water to refine. You also have to do more harvesting and disturb more land to get the same amount of product Strategies of mining Overburden vs. spoils I Surface mining strategies bulldozer Tailings and Slag vs Target Material Slag Cyanide Heap Leaching 1 Environmental impacts of mining Bare earth leads to soil erosion which leads to no topsoil which leads to no vegetation which leads to desertification all the way to primary succession oflightthatasurfacereflects fraction Lowered albedo leads to increased temperatures Mining equipment uses fossil fuels If there’s water nearby increased turbidity, decreased albedo, increased temperature, effects organisms that live there Acid Mine Drainage Sustainable mineral use ◦ In addition to the impacts of mining, we also have to consider that minerals are nonrenewable resources. ◦ Reducing waste and recovering and recycling used mineral resources are key to the sustainable use of minerals.  Remediation techniques Fix things back to the way they used to beputoverburdenback Enrich topsoil Plant native plants  5.10: Urbanization Urbanization is the movement of people from rural cities to densely populated cities Fewer farms and farmers exist today, resulting in reduced employment opportunities in rural areas Rural occupations include fishing, logging and farming Urban occupations are not connected directly with natural resources Urbanization is often associated with the depletion of natural resources Worldwide shift from rural to urban areas Benefits of urbanization Mass transit- lowering fossil fuel use per capita, efficient use of space Everything is close together- walking and biking, increases human activity levels As cities grow, they often grow up instead of out, which minimizes land impact  Environmental problems of urban areas Urban air and water problems High density of commercial enterprises in urban areas causes buildup of airborne emissions Particulates Sulfur, carbon, and nitrogen, oxides Volatile organic compounds Urban areas in developing nations have the worst air pollution in the world Urban areas are dominated by impermeable surfaces like buildings and roads, which increases runoff Urban runoff can contain multiple pollutants, and sometimes remains untreated, potentially contaminating waterways distant from the city Effects the water cycle  Urbanization disadvantages ◦ Saltwater intrusion ◦ When a freshwater aquifer is close to a body of salt water, overuse of the aquifer can not only result in depletion of the resource, but can also pull salt water into the freshwater aquifer ◦ Effects carbon cycle Use of fossil fuels- industry, cars, etc. Increased populations create a lot of waste which is released as CO2 or methane, which are greenhouse gasses  Urban sprawl Sprawl is the change in population distribution from high population density areas to low density suburbs that spread into rural lands, leading to environmental problems Sprawl results from development that places homes on spacious lots spread out over large areas far from urban centers. Most people who work in cities don’t live there, they commute. They live in suburbs for cheaper cost of living, more space, etc. Increasing road networks and the use of cars have continued the spread of suburban areas By allotting more space to each person, suburbs have spread human impact across the landscape, creating sprawl. Urban Sprawl Sprawl constrains transportation options, essentially forcing people to own a vehicle and spend much more time in it due to commuting distances. Pollution is increased by sprawl due to the use of vehicles. Cars directly release carbon dioxide, nitrogen, and sulfur-containing pollutants. Paved areas create runoff that may contain salt or motor oil. Sprawl promotes physical inactivity, as driving takes the place of walking in daily errands. As more land is developed, less is left as forests, fields, farmland, or ranchland.  5.11: Ecological Footprints ◦ Expresses the cumulative area od biologically productive land and water required to provide the resources a person or population consumes and to dispose of the waste the person or population produces ◦ Compare the resource demands and waste production required for an individual or society Increases Footprint Decreases Footprint Affluence (wealth) increases carbon and ecological Renewable energy use (wind, solar, hydroelectric) footprint Public transportation (less gas) Larger houses Plant based diet More travel (fuel) Less consumption, less travel, less energy use Meat consumption- more land, water, and energy Fossil fuel usage (heating, electricity, travel, plastic, etc.)  5.12: Introduction to Sustainability ◦ Living within the planet’s means, such that Earth and its resources can sustain us- and all life for suture generations ◦ Sustainable yield is the amount of renewable resource that can be taken without reducing the available supply ◦ Environmental indicators can guide humans to sustainability ◦ Biological diversity ◦ Food production ◦ Average global surface temperatures and CO2 concentrations ◦ Human population ◦ Resource depletion  5.13: Reducing Urban Runoff and Sustainable Development Increasing vegetation in urban areas helps to reduce runoff, decreases heat, and takes in excess CO2 Extended mass transit to commuter areas Permeable pavement- increases water filtration and reduces runoff Growing up instead of out Remediate brownfields- abandoned buildings create impermeable surfaces that no one is using. By tearing those down and replacing it with something people use or returning it back to its natural state, you reduce those negative effects. 5.14: Integrated Pest Management IPM is a combination of methods used to control pest species while minimizing the disruption to the environment It includes biological, physical, and chemical controls The goal is to reduce the amount of chemical pesticides used to reduce the pesticide treadmill and poisoning of non-target species and humans IPM does not want to exterminate all agricultural pests, these organisms are part of the trophic structure of that ecosystem and extermination isn’t sustainable or ideal in terms of biodiversity  Biological Control The most obvious alternative to chemical pesticides is biological control, where natural predators or parasites are introduced to eliminate the pest. In the 1920s, the cactus moth was successfully introduced into Australia to control the invasive prickly pear cactus. ◦ A modern example of biological control is the use of the Bacillus thuringiensis (Bt) soil bacterium, which produces a protein that kills many caterpillars and some fly and beetle larvae. ◦ Bt spores can be sprayed directly on plants. ◦ The gene responsible for producing the protein has been genetically engineered into crop plants, allowing them to produce the poison. When a pest is a non-native species, scientists may consider introducing a non-native predator to combat it. This is risky, because the full effects of introducing a new species cannot be predicted. The cactus moth employed in Australia to fight prickly pear cactus was also used in Caribbean countries, but has spread into the United States and is now consuming native cacti. IPM: Crop Rotation and Intercropping Benefits of IPM Drawbacks of IPM Decreases amount of chemical Complex process pesticides used Slow Economic savings due to less Can be expensive chemical pesticides used Sustainable Targets specific things instead of killing everything Minimizes loss of pollinators Minimizes health risk Decreases pesticide resistance 5.15: Sustainable Agriculture Sustainable agriculture- agriculture that fulfills the need for food and fiber while enhancing the quality of the soil, minimizing the use of nonrenewable resources, and allowing economic viability for the farmer. The preservation of soil is essential to maintaining sustainable food production practices Maintaining soil fertility is also important in practicing sustainable food production Sustainable Soil Conservation Methods Sustainable Management of Soil Fertility  5.16: Aquaculture Aquaculture is the farming of fish, shellfish, mollusks, crustaceans, or aquatic plants by an individual or corporation with the intent to sell the farmed organisms to consumers for profit Can occur in both marine and freshwater environments depending on the organisms being farmed Human population has greatly increased in recent history, which has caused the middle class to expand in developing nations. This growth has caused higher demands for quality protein. Wild fish harvests have been largely flat or declining since the 1990’s Aquaculture provides much needed income to fisherfolk, it is less time consuming and less dangerous than open-water fishing Aquaculture is more efficient at producing animal protein than terrestrial agriculture and requires far less fossil fuel inputs, acreage, and water consumption Aquaculture can help mitigate overfishing and provides affordable, high quality protein to humans efficiently and with resource use Disadvantages of Aquaculture Waste from organisms can pollute waterways, with excess nitrogen causing algal blooms and hypoxic conditions Uneaten food pellets can pollute waterways Farmed organisms may escape from pens and interbreed or compete with wild organisms The density of organisms in pens means infectious diseases and parasites can spread more easily These must be controlled using antibiotics and other medications Medication residue can contaminate surrounding waterways Diseases in farmed populations can spread to wild populations Forestry Forests are an important natural resource that provide ecosystem services to humans Food Medicine Fuel, fiber, and timber Carbon sequestration Air purification Flood and erosion mitigation Maintenance of biodiversity Recreation Aesthetic and cultural value  5.2 Clearcutting ◦ A forestry technique that involves removing all or most of the trees in a given area at once ◦ Clearcutting can be economically advantageous but leads to soil erosion, increased soil and stream temperatures, and flooding ◦ Soil erosion- caused by loss of stabilizing root structure, removes all soil organic matter and nutrients from forest and deposits sediments in local streams. ◦ Increased soil and stream temperatures- loss of tree shade increases soil temperature, soil has a lower albedo than leaves of trees, loss of tree shade along rivers and streams warms them ◦ Flooding and landslides- logging machinery compacts soil and increased sunlight dries it out, the loss of root structure means most of the top soil can be eroded very quickly, all of these factors decreases the water holding capacity of the soil and causes floods and landslides 5.17: Sustainable Forestry Collection of methods that attempt to mitigate the human impact of harvesting trees and using forest resources Mitigation of deforestation Deforestation is obviously unsustainable forest use There are numerous methods that can be employed to mitigate the effects and begin the sustainable use of forests Reforestation: the intentional restocking of existing forests and woodlands that have been depleted Buying and using wood from certified providers that use ecologically sustainable forestry techniques Selective harvesting Prohibiting logging in ecologically sensitive or highly biodiverse areas of forested land Transportation of felled trees via techniques that limit ecological disruption and soil compaction Reusing, recycling, and repurposing wood Sustainable Management of Pathogens in Forestry Diseased trees can threaten the health of the entire forest ecosystem IPM techniques can help minimize the threat of infestation in an ecologically sustainable manner Continual monitoring of the health of tree stands Knowledge of common pest species Understanding economic pest threshold Setting traps/manual weeding Biological control with natural predators Chemical control with repellants and pesticides, as a last resort The selective removal of diseased trees can also help slow the spread of infestation in a stand  The Role of Fire in Sustainable Forestry We tend to think of forest fires as a negative, but prescribed burns can actually improve forest health and are important sustainable forestry techniques Fire removes excess understory plants as well as dead tree limbs, needles, and branches This selective removal can help reduce the severity of natural forest fires by reducing the amount of dry matter available as fuel and can also help reduce pest infestations Advantages of Sustainable Forestry Disadvantages of Sustainable Forestry Mitigates deforestation Sustainable forestry methods often increase the Preserves biodiversity economic costs of using forest resources and reduce profit margins for timber companies Preserves critical ecosystem services forests provide Require forestry workers to be trained in how to properly use these techniques Using IPM and selective tree removal for pest management Reduces impact of pesticide use on non-target species, soil, and water Prescribed burns Lessens the severity of naturally occurring fires by removing underbrush and debris Encourages new growth of native species Helps manage pest species