Friday, September 20, 2019

The Overall Concerns Of Resource Depletion Environmental Sciences Essay

The Overall Concerns Of Resource Depletion Environmental Sciences Essay Recently, people become very concern about the environmental issues. Our environment is our surrounding, its a gift that we have to keep , take care of and serve. One of the main problems that facing the globe is resource depletion .Resource depletion either it was for non-renewable or renewable sources, it has negative influence in both society and economy. Depletion of resources will make them very expensive. Or even after years from now we will not find resource to pay for .Many institution raise this problem up to aware people about this risk, a suggested solution is renewable energy. We should start thinking about the next generations. Renewable energy will be always there, there is plenty of it for present and future, especially because the world is facing continuous growing in population which is considered the main reason for resource depletion. Abstract: In this report we started by explaining the meaning of resource depletion. We mentioned some causes of this problem. The main three parts of resource depletion that we choose are fossil fuel depletion, water depletion and forest depletion. For fossil fuel we suggested renewable energy technologies as solution. We choose to talk about solar energy, wind power and hydroelectric power. For the water depletion we show how water is important .Also we discussed some methods to maintain water which are reclaimed water, solar desalination and rainwater harvesting. The third type is forest depletion and we suggested recycling as solution The meaning of resource depletion: Resource of depletion; its an economic word which mean all natural resources that divided between renewable resources and non-renewable resources, have been exhausted within a region. Using the resources beyond its rate we thought any replacement for it is considered as resource depletion. The human nowadays use resources without care about if they can find it in the future for the new generation. The depletion of natural resources continues which have 11.8% of global environmental problem. An average of 23% of Imagine lands soils are degraded to the extent that their productivity is limited. 1% every year of the countrys forested area is going down. There are water shortages, and 100 high plant species are threatened during the dry seasons. Because of expansion and intensification of agriculture, among others also for reasons of commercialization and increase of global trade the pressure on the natural resources will increase. A lot of resources in the world have been decline a very year, such as fisheries, tropical forests, water, fossil fuels (oil, natural gas and coal) and materials. The first report to the Club of Rome, The Limits to Growth, was published in 1972. It marked the beginning of modern environmental policy. The report highlighted the impossibility of sustaining exponential economic growth and its associated Resource Depletion (1). The environmental policy has change to other policy filed in the twenty-five years after Limits to Growth, as example as we have released that the plenty resources of coal in the world, we cannot fully exploited because of the climate Change. Despite this the threat of Resource Depletion is still continue. Focusing on the mineral oil during the first and second oil crises (1973-1974, 1979) has been replaced by a wider picture of resources including groundwater, energy, land, fertile soil, forests and fish stocks. One common aspect of these resources is their depletion may have economic repercussions. Causes of resource depletion: Excessive or unnecessary use of resources Non-equitable distribution of resources Overpopulation Slash and burn agricultural practices, currently occurring in many developing countries Technological and industrial development Erosion Irrigation Mining for oil and minerals. Types of resource depletion: Fossil fuels depletion: The fossil fuels are very important key for energy in the world and for modern economic, which is non-renewable resource that takes a million of years to create. The fuels are; oil, coal and natural gas. It is 86% of the world of global energy supplies nowadays. Fossil fuel helps to produce cheap energy that modern industries depend on it. It can be burned and producing significant amounts of energy per unit weight .Also, it is primary source of the cheap energy that powers our modern Industrial Civilization that depends on it such as; automotive Industry, steel Industry and transportation Industry. Nowadays we are facing a huge level crisis in energy. Any careful examination of the writings and papers of the worlds leading energy scientists will convince the reader of the validity of the fossil fuel energy crisis. The U.S. Department of Energy Projects tell us; the demand of fossil fuel energy will increase approximately 60% between 2006 and 2030 globally. The energy crisis is caused by the depletion of fossil fuels. From the graph you can see the depletion of world fossil fuels energy from 1900 to 2300. The Industrial civilization cannot exist without oil. The prices of the oil have drawn attention to the issue of the relative supply and demand for basic oil that has a central place in the modern economy. The Knowledge of petroleum geology has made great advances in recent years. It transpires that the bulk of the Worlds current production comes from deposits formed in two brief and exceptional epochs, 90 and 150 million years ago. This tells us that oil is a finite resource, which means that it is matter to depletion. Is the oil running out? Yes, we started when we produced the first drum. But Running Out is not the major issue as the resource will not be finally exhausted for very many years. The important question that we should have answered it is: when will production reach a peak and begin to decline? Gas depletion you can see from the graph the amount of natural gas used between 1965 and 2004. This is look as depletion because gas is burned much more quickly than it is formed. There are limited natural gas reserves. During the 40 year period, the gas equivalent of almost 60 billion tones of oil was used up. The region that used the most gas over this period was the United States, the Russian Federation, the Ukraine and Canada. Nearly all the natural gas that has been burnt as fuel was burnt during these forty years, and the years since. Until about 1965 natural gas from oilfields was often considered hopeless, so was disposed of by flaring. It has since been used widely, as a fuel. Water depletion: Water is other important resource for irrigation, drinking, cleaning and in every part of the global. There are too kind of water; Groundwater and surface water. The water depletion is very important issue after the fossil fuels depletion because of decreasing in clean and fresh water in some location and areas. The United Nations Global Environment Outlook have Four reports estimate, a third of the worlds current population will live in areas with water shortage by 2025, while the remaining two-thirds are expected to be under water stress that mean almost 2 billion people. That means there will be no enough water in the future for sustain agriculture, energy production, industry and domestic life at all. The groundwater is an important resource throughout the world for some country especially US; it supplies many of the human needs. It is the source of drinking water for about half the total population and nearly all of the rural population, and it provides over 50 billion gallons per day for agricultural needs in the United States. A lot of area in the United States they have groundwater depletion. What mean Groundwater depletion? Groundwater depletion is a term that defined as long-term water-level declines caused by sustained groundwater pumping, is a key issue linked with groundwater use. We can compare water stored in the ground with the money that kept in a bank account. Pumping water out of the ground faster than it is replenished over the long-term cause a problem. The volume of the storage water in the ground is decreasing in many areas especially in the United States because of pumping. Groundwater depletion is primarily caused by sustained groundwater pumping and pumping g roundwater at a faster rate than it can be recharged can have some negative effects of the environment and the people who use the water, such as: drying up of wells reduction of water in streams and lakes deterioration of water quality increased pumping costs land subsidence The chart shows monthly-mean water levels from 1964 to 2003 for a well in Cook County, sourthwest Georgia. The well is used for irrigation and public-supply purposes and offers a good visual representation of long-term groundwater declines due to excessive pumping7. Forest resources depletion: The Echo systems help sustains life for millions of species. It is the forests that provide a home for a large majority of the species alive. Therefore the most important species are trees in these forests. There are many benefits that we can get from forests some of these benefits are; cleaner drinking water, a home for plants and animals, economic growth, clean air, recreational opportunities, reassuring future. Also there is another benefit we can get from trees is called oxygen. We would not be able to live If there were no trees to give us oxygen to breath. So this is a very important reason to protect forest which is staying alive. Forests have many resources that people can use to raise their living standards. For example; the wood for building houses and paper making. Some wood materials last a long time so they keep the house warm and make it easy to manufacture homes. Unfortunately the overpopulation and the demand for a higher standard of living are constantly increasing. Therefore the demand for more resources is increasing to levels that cannot be sustained any more. Since forests provide a large of resources to the worlds, so many forests are cut down or burned, because human demand and greed Look around yourself right now and you will find a product within your reach that is made of wood. The cause for cutting down forests and depletion is directly associated to manufacture paper products and lumber for other manufacturing like furniture. We use wood for everything in our live. It is used in home building, furniture, marine products and the list seems like its endless. Not only wood is good building material, but also has great aesthetic qualities. Unfortunately we dont always take in to account how many trees need to be cut down so we can have luxuries furniture in our lives. Another direct cause for forest depletion is simply burning forests for farmland. Many poor farmers burn or cut small area from the forests in some countries so they can have room for farming and cattle, these countries are undeveloped and have tropical rainforests. But the problem in the big scale is created when thousands of square acres a year burned by huge corporate farms. They need this much area to provide farming on a much larger scale to compete in the world market for food. The reason forests are burned is due to the rich minerals fertility of the soil. Some farmers in undeveloped countries they dont have any education in how they can re-use the soil. So that the soil is use up and left as a desert, while they burn and cut more forest to make another farm. The Amazon rainforest which located in South America is the largest in the world has fallen to be victim of deforestations. Also, as another example of country that has fallen to be victim of deforestations is Brazils mar ket which is the third of all the Latin countries. The Brazils foreign debt, except in the most unlikely of positive economic conditions, is simply unsustainable in the further years. The economical pressure on a country is an additional cause that forces a country to deforestation such as the case in Brazil. The data shown from 1978 to 1988 that 230,000 square miles was affected from deforestation, by Basic Science and Remote Sensing Initiative (BSRSI). That is 16.5% of the entire rainforest in the Amazon. The farming is another example shows the cause of deforestation. Between 1990 and 2001 the percentage of Europes process meat imports that came from Brazil rise from 40 to 74 percent according to the Center for International Forestry Research (CIFOR). By 2003 the growth in Brazilian cattle production-80% of which was in the Amazon-was mostly export driven, for the first time ever. As more roads are built to provide access to forests in undeveloped countries more deforestation will appear. As we side before about the benefit of the forests .We get a large part of our oxygen from plant such as trees and most of the trees live in forests. It is important for human to understand the problem with deforestation may have on our air quality. The gas that has an impact on the greenhouse effect is Carbon dioxide (CO2). There is a cycle between CO2 producers such as cars and CO2 consumers such as plants called the Global Carbon Cycle. The tropical forests hold 460-575 billion metric tons of carbon worldwide in the plants and soil. From 1850 to 1990 deforestation worldwide released 122 billion metric tons of carbon into the atmosphere, with the current rate being between 1.6 billion metric tons per year. Therefore deforestation plays a significant role in Global Warming and clean air. Also, another problem with deforestation is a decrease in biodiversity. The biodiversity is important for Ecosystem sustainability, agriculture, medicine and recreation, aesthetic and commercial val ue. There are about 5 to 80 million species that live on this world. The tropical rainforests are home to more than half of the species living in the world. After deforestation, many species cannot live and possibly go to extinct. For many resources we depend on these species, so their extension will take from us their benefits. The solution: For fossil fuel depletion: Renewable energy: Because what fossil fuel coal, oil and natural gas cause to our environment and because the scientist warn of decreasing of amount of fossil fuel. We need to use other sources to provide energy both for present and future generations. There are other alternative which give billions of people the energy they need more than that, it consider to be clean and low-carbon energy systems and they will never run out .these alternative are renewable energy such as solar energy ,wind power ,geothermal ocean energy, biomass and hydro energy. In this report we will concentrate in solar energy, wind power and hydropower which are clean sources and clean technologies. Different type of renewable energy varies according to the cost, local conditions and performance These sources of energy can replace fossil fuel. Reported from the European Renewable Energy Council 2004 said that renewable energy could provide the power needs, and supply 50% of the worlds energy by 2040. Not only have that, but renewable energy technologies dont produce greenhouse gases emissions and can addressed climate change. Japans Ministry has a study about the Environment; conclude that renewable energy could reduce greenhouse gas emissions to a level a 70% reduction by 2050. The graph below show the use of worldwide energy for all energy types .The Graph 2 show the expected future behavior by the EIA (Energy Information Administration) it shows that oil and coal will keep increasing. Nuclear power will increase but will not lead. While the condition of renewable energy is uncertain. They think that it capacity will explode. Graph 2: worldwide energy use by energy Type. Solar energy: Sunlight or solar energy sends out every day from the sun .is the most form of renewable energy. The usage of solar energy in renewable energy technology it either direct heat buildings and water and to generate electricity. or indirect because the heat from the sun cause the movement of the wind which we take benefit from it in wind power ,also it provide trees the main source to grow which used in biomass energy more than that sun light cause the evaporation which makes hydropower happen. The direct use of solar energy dont cause pollution in air or water more than that it is available everywhere on Earth. The light reaches us from the sun by two different radiation types. One of them reaches earths surface in an unbroken line which called direct, while the radiation that spread by clouds, dust, humidity and pollution is called diff. .so we have two technologies for the solar energy. One of them uses mirror to concentrate the direct radiation. PV cells and other solar technologies for diff radiation. Know if we want to ask ourselves why solar power? Because it doesnt bring co2 in one hour sun shine, the Earth receives more energy than human put away in whole year. Also, the Sun has enough helium mass to supply the Earth with energy for another five billion years. The Americas Department of Energy said that, if solar panels placed on 0.5% of USAs mainland landmass, it could grant for all of its electricity needs. It is true that solar energy is five times the fossil fuel price, but once it is applied it pay for it self The Environmental Impact of Solar energy technologies do not cause pollution, some thermal energy technologies need cooling by water, which can be recycled. Only small amounts of unsafe substances are formed in the manufacture of photovoltaic cells and CSP equipment. For the land required Most PV systems are installed on existing structures such as homes and buildings which doesnt need extra area . but CSP plants need large land, For example, One CSP plant near Las Vegas covers 400 acres and can produce 64 MW of electricity. Which is enough to power 15,000 homes annually. The cost of the solar energy decrease but it is still expensive. In U.S 2006 trade electricity prices for all sectors averaged 8 cents per kWh, and for housing electricity, the price averaged about 10 cents per kWh. But CSP systems generated electricity at a cost of 12 cents per kWh, while PV systems generated electricity for about 18 to 23 cents per kWh. PV systems usually generate more electricity during the hottest time as shown in the graph3 . And this is another advantage of solar energy. In Texas, the need is at peak in the summer because of air conditioning when the solar source is maximum. More than that, the most need for electricity is in the later afternoon period when existing solar energy is high. Graph 3: percentage of generate electricity by solar system among the year The Solar Electricity, to convert the solar energy to electricity. There are two ways which are photovoltaic and solar thermal systems. The name of Photovoltaic is from the words photo which means light and the word volt, the short of photovoltaic cells is PV cells or solar cells. Some example of PV which change sunlight into electricity in Solar-powered toys, calculators, and roadside lights as shown in the Figure1. Figure 1: PV cells The wide use of PV cells because it made from silicon material, it is the same material that makes up sand and it is the second most widespread material on earth. PV cells can provide power to anything that is powered by batteries or electrical power. Also because the transfer of sunlight into electricity happen silently and right away Solar Thermal Electricity, It has two names as well solar thermal systems and concentrated solar power (CSP), It also convert solar energy to electricity, but in a different way. This way need solar collector with mirror in order to gather the sunlight onto a receiver that heats a liquid. Then the hot liquid create steam to generate electricity in the same way of coal plants as shown in Figure 2. the usage of this type is wide .In Mojave Desert There are nine solar thermal power plants which create 360 MW of electricity. Figure 2: concentrated solar power Wind power What is the meaning of wind? Wind is the movement of air. When it happen? It happen when hot air moves up and cooler air swap it. The energy of moving air used long time ago in sailing and ext. Nowadays wind energy generates electricity by capturing the wind in wind turbines. How it happen? Wind power is in fact a form of solar power, it caused by heat that comes from the sun. Solar radiation causing the Earths surface to be warm and it heat the water, sand and stone at day time and it cool at bight. The hot air move up and that cause reduce in the atmospheric pressure near the surface of the earth which make the cooler air replace it. This movement called wind. The energy caused by the wind power is Clean and Renewable energy. It uses natural and infinite sources. More than that it doesnt cause pollution or waste The Energy caused by the wind is relative to the cube of wind velocity. The equation of wind power is the following: Power = density of air x swept area x velocity cubed , P =  ½.à Ã‚ .A.v3 velocity (v) is in m/s, at sea level (density of air is 1.2 kg/m3) the power density in the wind will range from 10W/m ² at 2.5m/s (a light breeze) to 41,000W/m ² at 40m/s (a hurricane). In general, wide areas have annual wind speeds below 3m/s this number is not useful for wind power system. For the area which have annual wind speeds more than 4.5m/s wind power will be economically useful. That why this source of energy is more economically practical in windy areas. In fact the energy which produced by a wind turbine can increase by 20% for each 10% increase in wind speed. The graph 4 below show that when wind speed increase the power output increase proportionally. Graph 4:the relationship between wind speed and power output. The world-wide require for wind turbines has been raising quickly over the last 15 years. In 2001 the wind energy industry set up 5,500 MW power generators. More than 24,000 MW of wind power is now expected to be in action around the world .the graph 5 below shows the increasing in depending on wind power throw the years. Graph 5: increasing of wind energy use. Turbines used to cover the demand of electricity. so , the size of the turbine enlarged from 100 kW to 1 MW of electricity generation power, even residential offshore as shown in the Figure 3 below. Figure 3: 2 MW Wind Turbines at 40 MW Offshore, Windfarm in Denmark. Hydropower The word Hydro means water. Moving water have energy and that what we call it Hydropower. Technology has made this energy to be able to change it to electricity. The force of Gravity, which attracts the objects and drags them down, it, pulls the water from high land to lower land. This water which falls down has a power. More than that, Water is a renewable source, because of the continuous cycle of evaporation and precipitation. But how this cycle happen? it always start from the sun , The heat of the sun reaches to water in the earth surface , and that lead to evaporation in ocean and other water surfaces and form clouds. After that the rain or snow falls down to earth, and drains into rivers and streams that run again to the ocean. As in the figure 4 .This moving water could power water wheels that operate mechanical processes, and captured by turbines and generators. The cycle of water is always there, it will not run out. Figure 4: water cycle. We imitate the natural behavior of moving water. By building dam in a river in order to capture the water, then it will formulate a big lake at the back of dam. We this lake is called a reservoir. When the water allowed moving by opening the dam it will run down and operate the huge wheels of turbine. From the power we get in this process we can generate electricity. Hydropower has more than 92 % among renewable energy as shown in graph 6 .It is commonly among developed countries around world. About 150 countries, nowadays there are around 2,000 dams in U.S only. Graph 6: amount of electricity generated from different types of renewable energy. In order to have continuous supply of electricity in an interconnected grid which rely in both wind and hydropower technologies. Hydropower can be used to cover for wind power and vice versa. That means when there is no wind, we can depend on hydropower. Also when there is low water period we can use wind to generate power usually generated by the hydropower systems. For water depletion: Why save water? Many people say, we dont have t consider water lost because water is covering 71% of the earth. However, most people dont know that this percent dividend to 1% for freshwater, 97% is too salty for human use, and the rest is frozen, and Figure 5 show how hard it is to find freshwater on earth ether it is ground water or iced. This sum up the 1/3 of the worlds population is already facing problems due to both water shortage and poor drinking water quality, and the UNESCO has predicted that by 2020 water shortage will be a serious worldwide problem. So, who is responsible to save water? Farmers, governments, engineers and people, they all play an important role to save water. Figue 5: Water distribution on earth in precentage. Governmental efforts: Some governments around the world developed an environmental policies and guidelines, some of them is provide water efficiency regulation. Their main policy is to sustain natural recourse such as water, and any sustainable development that serves future generations economically, environmentally, and socially. Examples for these organizations: The Australian National Water Quality Management Strategy (NWQMS) The Indian Ministry of Water Resources. The Quà ©bec Ministry of Sustainable Development, Environment and Parks U.S. Green Building Council The UNICEF Estidam Water sector in the United States USGS UN-HABITAT The Millennium Development Goals (MDGs) à ¢Ã¢â€š ¬Ã‚ ¦etc All of these organizations tend to improve the sustainable developments in their regions. Sustainable water There are soo many ways to sustain water, and we are going to discuses some of the known methods to maintain water. Reclaimed water: Is a term used for recycling water. Rather than dispose wastewater -sewage and greywater-, reuse it in non-potable uses, such as irrigation, dust control, and fire suppression. However, this reclaimed water need to follow up in some procedure to make it applicable to use. Wastewater treatment process, it is the process of removing physical, chemical and biological contaminants from sewage and wastewater through physical, chemical, and biological processes, to manufacture an environmentally safe fluid suitable for disposal or reuse. And from figure 6 we can study the treatment process: Preliminary Treatment It is a physical process by using devices to remove or cut out large objects such as inorganic solids, oil and greases; to protect pumping equipment and facilitate subsequent treatment processes from damage these object can do. Examples for these devices: Screens Comminuting devices (shredders , cutters, grinders) Grit chambers Preparation tanks   And chlorination is needed in preliminary treatment.   Primary Treatment After Preliminary process, some suspended solids still contained by the treatment water, it is removed by physical process of sedimentation through a sedimentation tanks which hold the treatment water for 2 or 3 hours, and the suspended solids -sludge- settle on the tank are removed with mechanical scrapers and pumps. And the floating sludge are removed by surface skimming equipment. Secondary Treatment In this stage a microorganisms are involved to remove dissolved organic matter from what remained in the wastewater. These microorganisms feed on organic matter from sewage as their energy supply. Final Treatment In the final treatment chorine is add to remove all pollutants from the water, and the product is usable water. Figure 6: Waste-water treatment process. Solar desalination Desalination is a method to remove salt and minerals from water (ocean). Solar is referring to the energy used for this process. There are two types of solar desalination: Reverse Osmosis Its a simple operation of water desalination, through applying pressure to the sea water in one side of the system through a membrane and salt is essentially filtered, with a mathematical. This method used in large-scale desalination implementations where electricity is less costly. Here, solar energy is collected and converted into electrical or mechanical energy to initiate the process. From figure 7 we can explore the process. Figure 7: Reverse Osmosis process The solar humidification-dehumidification (HDH): Also called the solar multistage condensation evaporation cycle (SMCEC) or multiple-effect humidification (MEH), is a technique that simulates the natural water cycle on a shorter time frame by evaporating using solar energy (sun) and condensing water to separate it from other substances. And the condensed water is collected in a chamber. As shown in figure 8. Figure 8: the HDH process Rainwater harvesting Is a very simple system of collecting rainwater before it reaches the aquifer through the storm water harvesting, which is a surface especially prepared for this purpose, such as buildings roof, and ground; to reuse it as drinking water, irrigation, water for livestock, and any other apply. However, this system is not suitable for every where, where it is used in areas with an average rainfall greater than 200  mm/ year. first water is collected via the storm water harvest (roof), then transfer through gutters and pipes which includes sufficient incline to avoid standing water, and strong to carry large amount of rainwater. Storage tanks should be covered to prevent mosquito breeding and to reduce evaporation losses, contamination and algal growth. Figure 9 conclude the procedure. Figure 9: Rainwater harvesting system For forest depletion: Why save forest? Cities, massive projects, farmlands, factories, firewood, tables, books, newspaper à ¢Ã¢â€š ¬Ã‚ ¦etc. What is there origin? Forest. Through history human activities destroyed and deforest the forest around the world, cities such as Ur, Uruk, and Babylon contributed deforestation massively of surrounding areas, which are forest. Agriculture, in the other hand, was one of the main reasons of forest deforestation, in order to use it to harvest. So why we should concern about forest and protect it? Well, if there is no forest, there is no trees and plant, no trees no species, no ecosystem, and no reduction of carbon sinks; which lead to a bigger problem known as global warmingà ¢Ã¢â€š ¬Ã‚ ¦ Facts: once forests covered14% from land surface; and now they cover only 6%, and if it is keeping in that track its going to be more decrease in this percentage, as the Forest transition theory Predicts, as shown in Graph 7. Graph 7: The forest transition theory Because of the massive developing and industry, every 1 sec there is a loss of about one and one-half acres of rainforest. The major authorities to blame are governments, multi-national logging companies, and land owners. <

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