Sunday, September 29, 2019
Geography Prelim Notes
Geography Preliminary Exam Outline 20 multiple choice ââ¬â skills Short Answer Questions ââ¬â Biophysical Interactions (some or all or how they integrate), population and culture integration. Extended response ââ¬â Natural resources ââ¬â one or a combination of the four points Geography Preliminary Notes The Biophysical Environment * The Biophysical Environment is the interaction of all abiotic and biotic elements found on the planet. * Expressed another way the BPE is made up of all the features of the physical and the built environment and how these features interrelate. The BPE is then the interactions, which occur between the Atmosphere, Lithosphere, Biosphere and Hydrosphere. ATMOSPHERE * Atmosphere, mixture of gases surrounding any celestial object that has a gravitational field strong enough to prevent the gases from escaping; especially the gaseous envelope of the earth. The principal constituents of the atmosphere of the earth are nitrogen (78 percent) and ox ygen (21 percent). The atmospheric gases in the remaining 1 percent are argon (0. 9 percent), carbon dioxide (0. 3 percent), varying amounts of water vapour, and trace amounts of hydrogen, ozone, methane, carbon monoxide, helium, neon, krypton, and xenon. * The water-vapour content of the air varies considerably, depending on the temperature and relative humidity. With 100 percent relative humidity the water-vapour content of air varies from 190 parts per million (ppm) at -40à ° C to 42,000 ppm at 30à ° C. Minute quantities of other gases, such as ammonia, hydrogen sulphide, and oxides of sulphur and nitrogen, are temporary constituents of the atmosphere in the vicinity of volcanoes and are washed out of the air by rain or snow.Divisions of the Atmosphere: Without our atmosphere, there would be no life on earth. A relatively thin envelope, the atmosphere consists of layers of gases that support life can provide protection from harmful radiation. Issues related to the Atmosphere * Daily weather conditions, climatic conditions (seasonal/short-term/long-term/cyclical) * Global warming, Greenhouse Effect (GHE) * Ozone depletion * Acid rain * Smog, photochemical smog, brown haze * Radioactive fallout Atmosphere Impacts Oxides and other pollutants added to the atmosphere by factories and automobiles have become a major concern, however, because of their damaging effects in the form of acid rain. In addition, the strong possibility exists that the steady increase in atmospheric carbon dioxide, mainly as the result of fossil-fuel combustion over the past century, may affect the earth's climate (for example enhanced Greenhouse Effect). * Similar concerns are posed by the sharp increase in atmospheric methane.Methane levels have risen 11 per cent since 1978. About 80 per cent of the gas is produced by decomposition in rice paddies, swamps, and the intestines of grazing animals, and by tropical termites. Human activities that tend to accelerate these processes include raising more livestock and growing more rice. Besides adding to the greenhouse effect, methane reduces the volume of atmospheric hydroxyl ions, thereby curtailing the atmosphere's ability to cleanse itself of pollutants. (for example photochemical smog) Atmosphere ââ¬â Ozone DepletionThe ozone layer became a subject of concern in the early 1970s when it was found that chemicals known as chlorofluorocarbons (CFCs), were rising into the atmosphere in large quantities because of their use as refrigerants and as propellants in aerosol dispensers. The concern centred on the possibility that these compounds, through the action of sunlight, could chemically attack and destroy stratospheric ozone, which protects the earth's surface from excessive ultraviolet radiation. HYDROSPHERE * The hydrosphere refers to all liquid and frozen surface waters, groundwater held in soil and rock, and atmospheric water vapour. Water is the most abundant substance at the surface of the Earth. About 1. 4 b illion cubic kilometres of water in liquid and frozen form make up the oceans, lakes, streams, glaciers, and groundwater. * Central to any discussion of the hydrosphere is the concept of the hydrologic cycle. This cycle consists of a group of reservoirs containing water, the processes by which water is transferred from one reservoir to another (or transformed from one state to another), and the rates of transfer associated with such processes.These transfer paths penetrate the entire hydrosphere, extending upward to about 15 kilometres in the Earth's atmosphere and downward to depths in the order of five kilometres into the crust. * Although water storage in rivers, lakes, and the atmosphere is small, the rate of water circulation through the rainââ¬âriverââ¬âoceanââ¬âatmosphere system is relatively rapid. The amount of water discharged each year into the oceans from the land is approximately equal to the total mass of water stored at any instant in rivers and lakes. The biosphere, though primarily H2O in composition, contains very little of the total water at the terrestrial surface, only about 0. 00004 per cent. Yet, the biosphere plays a major role in the transport of water vapour back into the atmosphere by the process of transpiration. Impact of Human Activities on the Hydrosphere * The activities of modern society are having a severe impact on the hydrologic cycle. * Humans alter the natural functioning of the water cycle through quantitative or qualitative changes to the cycle. For example the dynamic steady state is being disturbed by the discharge of toxic chemicals, radioactive substances, and other industrial wastes and by the seepage of mineral fertilizers, herbicides, and pesticides into surface and subsurface aquatic systems. Inadvertent and deliberate discharge of petroleum, improper sewage disposal, and thermal pollution also are seriously affecting the quality of the hydrosphere. * Humans alter the quantity of water available throu gh by a range of activities such as the construction of Dams.Weirs, irrigation schemes, aqueducts, reservoirs, dyke & levee schemes and land reclamation projects. * In more subtle ways humans through enhancing the Greenhouse Effect may be changing regional climates and therefore rainfall patterns within regions. * While large scale dams can mitigate flood damage, provide Hydro-electric energy and reliable water supply they also present significant environmental and ecological costs. * People alter the quality of water in many ways such as through domestic, agricultural, commercial and industrial pollution. The pollution of waterways is classified according to point or non-point pollution. * Pollution in waterways can mean the quality of water is unfit for human consumption (toxic to humans) or of a low enough quality to seriously impact on the ecology of the water system. LITHOSPHERE * The Earth's outermost rigid, rocky layer is called the lithosphere. It is broken, like a slightly cracked eggshell, into about a dozen separate rigid blocks, or plates. There are two types of plates, oceanic and continental.An example of an oceanic plate is the Pacific Plate, which extends from the East Pacific Rise to the deep-ocean trenches bordering the western part of the Pacific basin. The North American Plate exemplifies a continental plate. * The upper layer of the lithosphere is termed the crust. * The earthââ¬â¢s crust is comprised of bedrock material in various situ * Rocks are commonly divided into three major classes according to the processes that resulted in their formation.These classes are (1) igneous rocks, which have solidified from molten material called magma; (2) sedimentary rocks, those consisting of fragments derived from pre-existing rocks or of materials precipitated from solutions; and (3) metamorphic rocks, which have been derived from either igneous or sedimentary rocks under conditions that caused changes in mineralogical composition, texture, and internal structure. * Elements of weathering, erosion and gradational forces over time then shape these rock components into landform.This is known as the geomorphological process. * Such forces as tectonic plate movement, fluvial action, gradational forces and the action of the wind and sun shape landform features. * Tectonic plates move in three main ways relative to each other. Translation, seduction and convergence (Spreading). The results of this plate movement is often seen as volcanic activity (eruptions, geysers, hot springs) as earthquakes or tremors and in subsidence, land slips and slumping. * Fluvial action is the process of water eroding, transporting and depositing rock material. Wind can erode rock material by blasting, while the sun heating up rock and the rock cooling can break it down in a process call exfoliation. The top three soil issues confronting Australia are; 1. Loss of valuable topsoil due to over-clearing and subsequent erosion 2. Soils salinity ââ¬â as result of over-clearing and or irrigation rasing the water table and bringing salt to the surface. 3. Acid Sulfate soil exposure ââ¬â as a result of construction and mining exposing acid sulfates locked up in soil and these sulfates leaching into local waterways. BIOSPHERE The Biosphere is defined as the relatively thin life-supporting stratum of the Earth's surface, extending from a few kilometres into the atmosphere to the deep-sea vents of the oceans. * The biosphere is a global ecosystem composed of living organisms (biota) and the abiotic (nonliving) factors from which they derive energy and nutrients. * The biosphere can be broken down into segments of abiotic and biotic components, called ecosystems. Oceans, lakes, and wetlands are examples of aquatic ecosystems, while forests, deserts, and tundra are examples of terrestrial ecosystems.Through these systems, energy flows and chemicals essential to life are cycled in what is known as biogeochemical cycles. * The biosph ere itself can be studied as a worldwide ecosystem through which the interconnectedness of all life and life-supporting systems on the Earth can be understood. * The earthââ¬â¢s biodiversity (total known stock of varying species of fauna and flora on the planet) is classified into several major Biomes. Each Biome is made up of a multitude of interconnected and interrelating ecosystems. An ecosystem is defined as the complex of living organisms, their physical environment, and all their interrelationships in a particular unit of space. * An ecosystem can be categorized into its abiotic constituents, including minerals, climate, soil, water, sunlight, and all other nonliving elements, and its biotic constituents, consisting of all its living members. Linking these constituents together are two major forces: the flow of energy through the ecosystem, and the cycling of nutrients within the ecosystem. Cycles within ecosystems which transfer / transform energy and matter are known as t he Biogeochemical cycles (eg. Carbon, Oxygen, Nitrogen, Phosphorous etc.. ) * The biosphere supports between 3 and 30 million species of plants, animals, fungi, single-celled prokaryotes such as bacteria, and single-celled eukaryotes such as protozoans. Of this total, only about 1. 4 million species have been named so far, and fewer than 1 percent have been studied for their ecological relationships and their role in ecosystems. * A little more than half the named species are insects, which dominate errestrial and freshwater communities worldwide; the laboratories of systematises are filled with insect species yet to be named and described. Hence, the relationships of organisms to their environments and the roles that species play in the biosphere are only beginning to be understood. BIOPYSICAL ENVIRONMENT Impacts of Humans on the Biophysical Environment * The biosphere supports between 3 and 30 million species of plants, animals, fungi, single-celled prokaryotes such as bacteria, a nd single-celled eukaryotes such as protozoans. Of this total, only about 1. million species have been named so far, and fewer than 1 percent have been studied for their ecological relationships and their role in ecosystems. * A little more than half the named species are insects, which dominate terrestrial and freshwater communities worldwide; the laboratories of systematises are filled with insect species yet to be named and described. Hence, the relationships of organisms to their environments and the roles that species play in the biosphere are only beginning to be understood. Management Strategies for human impacts on BPE Management strategies can be based on a number of approaches such as reactionary, precautionary or proactive management. * As many issues have multiple causal factors at a variety of scales any successful management strategies must be designed with this in mind. Often the real measure of success of a management strategy is a direct reflection of effectiveness or otherwise of a co-ordinating authority. * An example of this need for a co-ordinated response to management can be seen through reviewing the Murray Darling Basin Commission (MDBC).This authority must oversee management strategies in literally hundreds of sub-catchments of the Murray Darling river and across local, state and federal levels of jurisdiction. Natural Resources Definition of a Natural Resource A natural resource is any part of the biophysical environment that can be used in some way to satisfy human needs. For example; air, water, forests, minerals. They can either be either RENEWABLE or NON-RENEWABLE. RENEWABLE RESOURCES Renewable resources are those that are naturally renewed within a sufficiently short time span to be useful to human beings.There are two categories of renewable resources: * Non-critical zone resources * Critical zone resources Non-critical zone renewable resources: * These types of natural resources remain renewable irrespective of how much and ho w often humans use them * Some examples include solar energy, tides, wing, waves, water and air. Critical zone renewable resources: * These are resources that naturally renew within short periods of time but can be affected by how much and how often humans use them, That is humans use them before they can be renewed. * Examples include fish, forests, animals, soil, underground water (aquifers)NON-RENEWABLE RESOURCES * These are resources that have taken millions of years to formââ¬â¢ * These are resources that are deemed to be in fixed supply that is once they are used they can never be replaced. There are two categories of non renewable resources; * CONSUMED BY USE and * RECYCLABLE OR THEORETICALLY RECOVERABLE Consumed by use Non-renewable * These are resources that once used they can not be replaced. These are basically the fossil fuels such as oil, natural gas and coal. There are called fossil fuels because they were once living organisms million years ago. * Because of the ra te of use in recent times these resources could ace exhaustion. It is predicted that after 2008 that oil will reduce as we have used it up. Recyclable or Theoretically Recoverable Non-renewable * These are the metallic minerals that are mined such as iron ore, aluminum copper, gold, silver etc. These also take millions of years to be created and once used they too cannot be replaced; the significant difference is that these resources can be reused or recycled. Think of aluminum cans or metal scrap yards. What constitutes a resource? For these resources defined earlier several conditions must exist before it can actually become a resource. 1.It must be recognized as being a resource indirectly or directly. 2. There must be the skills, equipment and social organization present to transform the resource into something useful. 3. The transformation must be achieved at a cost and convenience that make it more appropriate than an alternative. 4. The adverse impacts generated by the activi ty must be acceptable to society. What a natural resource is, depends on a number of factors; 1. Economic ââ¬â what is the cost of extraction e. g. , extracting petroleum out of deep-sea deposits is expensive and risky ââ¬â the deep sea well in the golf of Mexico. 2.Cultural ââ¬â What is a resource for one culture might not be for another e. g. Kangaroo meat. 3. Technology ââ¬â the resource might not be technologically possible at the moment e. g. fusion power 4. Political ââ¬â governments might promote exploitation of natural resources for strategic, economic & political reasons e. g. the cotton industry in Australia is a result of government policy in the 1960s that wanted to reduce our reliance on imported cotton. 5. Environment and health factors ââ¬â concerns about the impact on the environment and the health of people and ecosystems may effect the nature and rater if resources exploitation.Environment + Impact Statements (EIS) are often used to assess t he impact on ecosystems of the exploitation of a resource. Economic & political issues related to the use of natural resource, their ownership and management 1. Rate of use: Supply and Demand * Economically, natural resources will be used at a higher rate while that resource is in demand. * If demand is reduced over time it could have economic repercussions for the country that relied on its sale ââ¬â relevant to the economic well being of many developing countries. They take out large loans to help develop their country based on the performance of selling their natural resources * Once demand decreases their ability to pay back the loan is reduced which then makes the country more in debt. * Money made from selling the resources is used to pay off interest on the loans and little is put back into the country to make it better off. 2. Continued demand for a resource * Can jeopardise economic prosperity due to economically unsustainable practices * Uncontrolled exploitation may j eopardise long term production levels.A good example of this is fishing. * May cause stocks to be reduced * Threat to the preservation of the fish species * Industry and jobs would be lost * Boat owners would incur increasing debts * Food supplies would be threatened by high prices and limited availability Political Issues 1. Opposing views * Political issues of resource use can arise when competing groups wish to use the same resources. * Countries who dispute ownership of a major resource e. g. the waters of a river that flows through more than one country. * Subgroups within a society
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