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hbr review Moreton Hall School

Ecosystems are systems through which incoming solar energy is captured and moved through a hierarchy of life forms. hbr review Moreton Hall School. Ecosystems are characterized by the critical thinking courses clifton college, complex interactions between the abiotic and biological environments. It involves a number of major systems- the biosphere, the lithosphere, the hydrosphere and the atmosphere. Ecosystems feature a set of processes by which nutrients are retained and recycled. How to write reflective essay Les Roches Marbella International School of Hotel Management. Ecosystems are dynamic: that is ever changing due to natural or human events Ecosystems are usually classified according to their dominant feature e.g.: polar ecosystem Land boxed ecosystems are called terrestrial e.g.: forests Water boxed ecosystems are called aquatic e.g.: coral reefs The zone of transitions between ecosystems is called an ecotone All the world’s ecosystems together are called the ecosphere. The functioning of an ecosystem refers to the ecosystem’s ability to hbr review Moreton Hall School capture, store and a-g requirements for high school montverde academy, transfer energy, nutrients and hbr review Moreton Hall School, water. Ecosystems depend on 2 basic processes:- These processes link the energy, chemicals and organisms of an ecosystem. Nutrients such as oxygen, carbon, nitrogen and phosphorus are constantly cycled through ecosystems, making them available for plant growth. Water is also cycled through ecosystems and is important in allowing other cycles to take place. The earth is writing analytical essay les roches jin jiang international hotel management college, a vast storehouse of carbon. Only a small amount of this is critical thinking text st. clair college, available for hbr review Moreton Hall School use in ecosystems. Most carbon is a-g requirements for high school montverde academy, available as carbon dioxide CO², plants extract the carbon from CO² and give off oxygen. Carbon cycle varies in time and space. Humans can have a huge impact on the hbr review Moreton Hall School, carbon cycles: releasing long term stores of CO² by mining and burning of fossil fuels large scale destructions of forests, again releasing large amounts of CO² into the a-g requirements for high school montverde academy, atmosphere. As CO² is a greenhouse gas, the impact of humans has been the so-called “enhanced greenhouse effect”. The Nitrogen cycle The Oxygen cycle The Phosphorus cycle The Hydrological cycle energy flow. All life depends on energy from the critical thinking courses clifton college, sun. Energy flows through ecosystems by means of food chains and food webs. Solar energy is absorbed by plants and made into hbr review Moreton Hall School, usable chemical energy through photosynthesis. This “energy” is consumed by other living organisms which in hbr review Moreton Hall School, turn provide a food and energy source for other organisms. The system is known as a food chain, or, if more complex, a food web. Organisms can be divided into trophic (or feeding) levels. At each level of a food chain, energy is lost, therefore more bulk must be consumed. In all ecosystems the number of consumers at higher levels is smaller because of hbr review Moreton Hall School, the energy loss. How energy flows and critical thinking text st. clair college, nutrient cycles occur (i.e. hbr review Moreton Hall School. how ecosystems function) is affected by how the 4 components of the biophysical environment interact. Abiotic influences on ecosystems Celestial. Celestial influences include the sun and the moon influencing the amount of how to write reflective essay les roches marbella international school of hotel management, day, night, heat, light and gravitational pull on the earth. Earth influences include seasonal changes, rainfall, temperature and hbr review Moreton Hall School, wind patterns, tidal changes and ocean currents. Chemical influences include sea spray blown inland, nutrient up welling in the oceans and the fallout from the hbr review Moreton Hall School, atmosphere of sulphur dioxide and hbr review Moreton Hall School, volcanic activity. Major events influences such as large volcanoes, tsunamis, fires and storms. Biotic (living) influences Life cycles. Life cycles influence food chain relationships. Migration behavior patterns. Migration behavior patterns of birds and animals influence such things as vegetation patterns, seed dispersal and cross-pollination. Population dynamics (explosions and crashes in populations) influence species interactions. Adaptations influence the distribution of species in an ecosystem. Species interactions determines the maintenance, health and functioning of ecosystems. The Atmosphere is the main source of the climatic factors that impact on sample of academic writing essay curtin university singapore, ecosystem functioning. Climatic factors such as temperature and the amount of rainfall determine the nature of all factors within the ecosystem and the speed at which they function. Examples of the effect of the atmosphere on ecosystems are diverse: The warm moist climate of the rain forest ecosystem is the main reason why they are so dynamic. These conditions accelerate the rate of plant growth, the decay of dead material and the take-up of hbr review Moreton Hall School, minerals. Circulation patterns in the atmosphere determine spread of pollutants. The Hydrosphere. The Hydrosphere is closely linked to the atmosphere. It is, after all, the hbr review Moreton Hall School, atmosphere that determines the nature of the water cycle in a particular area. For example polar ecosystems are cold deserts with annual rainfalls of hbr review Moreton Hall School, less than 250mm and very little available fresh water. Because of the extreme cold and the low precipitation, polar ecosystems function very slowly. In tropical rain forests, as large amounts of rain fall at one time, they can maintain high biodiversity levels. Large bodies of water moderate the temperatures of adjoining land masses because water heats and hbr review Moreton Hall School, cools more slowly than land. The lithosphere determines the nature of soils and provides habitats for many of the decomposer organisms that recycle the minerals essential to the plants forming the basis of the food web. The lithosphere stores mineral nutrients and also stores water within the soil's interstitial spaces where it is available for use by plants. It determines the nature of soils and provides habitats for many of the decomposer organisms. Depending on how porous the soil is, the area may turn into a wetland or desert etc. In areas of non-porous clays, for example, wetlands may develop because water is trapped close to or above the hbr review Moreton Hall School, surface. Landforms also affect ecosystems. Small variations in elevation can result in marked differences in plant communities because of changes in availability of moisture. Average temperatures decrease with increasing altitude, so the climate and ecosystems of mountains often differ markedly from those of nearby valleys and plains. The biosphere is the domain on or near the earth’s surface here the environmental conditions enable solar energy to produce the hbr review Moreton Hall School, chemical changes necessary for life. The biosphere consists of 2 types of organisms: Autotrophic – self sufficient manufacturers of food. Use solar energy, water, carbon dioxide and nutrients from soil to produce energy and nutrients. Heterotrophic – consumers – herbivores, carnivores and omnivores, decomposers. Nearly all life on earth exists in a narrow zone extending from around 200m below the surface of the sae to about 9000m above sea level. The interdependence of critical thinking courses clifton college, all parts of an ecosystem that creates their fragility. Because of human use of technology to manipulate the environment, other elements now depend upon humans for survival. Technological advances have made humanity see itself as a separate entity of the ecosystems that support it. Development of ‘technosphere’ has encouraged ‘growth is good’. In some places now, the hbr review Moreton Hall School, technology must maintain the ecosystem of hbr review Moreton Hall School, it falls. What is biodiversity? Life has undergone changes in response to essays writing in english institut montana zugerberg changes in environmental conditions over time. hbr review Moreton Hall School. Species have become extinct and writing analytical essay les roches jin jiang international hotel management college, new ones have evolved. The result of these changes through time is present variety of writing analytical essay les roches jin jiang international hotel management college, life forms that are found on Earth. This biological diversity, or biodiversity, represents the variety of life forms that are best suited to survive the conditions currently existing on hbr review Moreton Hall School, Earth. Biodiversity includes three things: Genetic diversity - variations in the genetics of individuals within a species. Species diversity - the variety of species in different habitats. Ecological diversity - the variety of biological communities that interact with each other and the non-living environment. The variety of genetic information contained in all the individual plants, animals and micro-organisms Favors the survival of sample of academic writing essay curtin university singapore, a species because it increases the chance that some members of the species will have characteristics that help their survival if the population is essays writing in english institut montana zugerberg, subject to stress. (the plant or animal has genes that over hbr review Moreton Hall School time are now suited to survival needed in this particular ecosystem) Genetic diversity is the variety of genetic information contained in all the individual plants, animals and micro-organisms. Genetic diversity occurs within and between populations of species as well as between species. Genetic diversity favors the survival of the species, because it increases the chance of some members of the species will have characteristics that aid their survival if the population is hbr review Moreton Hall School, subject to stress. A measure of the number of species at hbr review Moreton Hall School, each trophic level of an ecosystem When ecosystems are diverse, there is a range of pathways for hbr review Moreton Hall School the ecological processes. Species diversity is a measure of the number of species at each trophic level of an ecosystem. The greater the species diversity the more robust the ecosystem. Ecosystem diversity is the variety of habitats, biotic communities and hbr review Moreton Hall School, ecological processes, as well as the diversity present within ecosystem in terms of habitat differences and the variety of ecological processes. The extent is the hbr review Moreton Hall School, product of a variety of factors. The most important are the microclimatic variations created by the physical features of an area. Ecosystems that are restricted to relatively small areas or subject to extensive damage are particularly vulnerable. In a rainforest ecosystem a loss of writing analytical essay les roches jin jiang international hotel management college, small areas can result in the extinction of a plant or animals species but as savanna grasslands have large populations of small numbers of species over much larger areas. The Extent of terrestrial ecosystems varies in accordance with many factors, the critical thinking text st. clair college, most important of which is climate. But extent is not always easy to establish; there is usually a great deal of overlapping of ecosystem boundaries. Ecosystems that are restricted to sample of academic writing essay curtin university singapore relatively small areas or have already been subject to extensive disturbance are especially vulnerable. A-g requirements for high school Montverde Academy. Tropical rain forests, for example, have relatively small populations of a large number of hbr review Moreton Hall School, species confined to relatively small, localized communities. The loss of a-g requirements for high school montverde academy, even small areas of rain forest can lead to the extinction of plant and animal species. Savanna grasslands, on the other hand, have large populations of a relatively small number of species spread over much larger areas. The loss of a small area of grassland therefore need not result in the extinction of critical thinking text st. clair college, an animal of plant species. The latitude, distance from the sea and altitude play decisive roles in determining climate and ultimately the nature of particular ecosystems. Some ecosystems are located in environments we consider extreme: deserts, the polar regions and high mountain peaks. Organisms living in these regions must be highly specialized. The greater the degree of specialization an organism has to a particular set of environmental conditions, the more vulnerable that organism is to changes in those conditions. The location of ecosystems plays a large role in determining their nature, including their vulnerability. Climatic variations produced by latitude, altitude and distance from the sea (continentality) determine the nature of terrestrial. ecosystems. On a smaller scale, microclimatic conditions, such as slope and location of water bodies, play a role in creating diversity in terrestrial ecosystems. The greater the degree of critical thinking courses clifton college, specialization an hbr review Moreton Hall School, organism has to a particular set of hbr review Moreton Hall School, environmental conditions the more vulnerable the organism is to changes in hbr review Moreton Hall School, those conditions. Writing analytical essay Les Roches Jin Jiang International Hotel Management College. There are two species of corroboree frogs in the Australian Alps, for example. The northern species lives only in the alpine bogs and leaf litter of Namadgi National Park in NSW. The southern species lives in the sphagnum bogs near Mt Kosciusko. Both frog species are listed as threatened. If global warming occurred, the habitat for writing analytical essay les roches jin jiang international hotel management college the frogs could change and their survival could be at risk. Many ecosystems contain specialist populations like this, and it is usually these species that are most vulnerable to changes because of their inability to adapt quickly to changing conditions. Interdependence (related to species diversity) Greater the level of interdependence, greater the ecosystem’s ability to absorb change. Ecosystems that have low levels of a-g requirements for high school montverde academy, interdependence are much more vulnerable to change (if the animals and plants in the ecosystem do not depend on each other as much, the ecosystem is hbr review Moreton Hall School, more vulnerable to change) Interdependence or linkages between species is closely related to species diversity. Ecosystems with a high degree of interdependence have a higher capacity to absorb change while ecosystems with low levels of interdependence are more vulnerable to change. For example there are few linkages up through the. food chain of the oceans around Antarctica. Krill are the dominant primary consumer organism and the main source of hbr review Moreton Hall School, energy (food) for some species of whale. There are on intermediary stages in the food chain. Any reduction in the supply of krill, from large-scale commercial harvesting for example, will directly impact on the number of whales that ecosystem can support. Interdependence can take very subtle forms. For example some flowering plants can be fertilized by writing analytical essay les roches jin jiang international hotel management college, only one species on insect. Sample of academic writing essay Curtin University Singapore. This insect may, in hbr review Moreton Hall School, turn, be dependent on some other organism for part of its life cycle. hbr review Moreton Hall School. Anything that jeopardizes this third organism, therefore, will affect the reproductive success of the flowering plant. Resilience is a natural function of ecosystems to adapt to the changes and restore equilibrium after an episode of stress or change, either natural or man made. The greater the critical thinking text st. clair college, degree of biodiversity is, the a-g requirements for high school montverde academy, greater the hbr review Moreton Hall School, resilience in that ecosystem. Grasslands generally have a high resilience to fire and regenerate quickly. This is because their roots are underground. But grasslands can be destroyed through overgrazing or ploughing up the roots of the grasses to plant crops. Long-term damage to ecosystems occurs when the size, intensity and duration of critical thinking text st. clair college, the changes prevents the hbr review Moreton Hall School, recovery of critical thinking text st. clair college, the affected components of hbr review Moreton Hall School, the ecosystem. Species that are successful in regenerating and adapting are less vulnerable to changes in sample of academic writing essay curtin university singapore, their ecosystem. Events like bush fires or prolonged droughts are part of the natural cycle in hbr review Moreton Hall School, some ecosystems and species are able to cope with theses stresses. Their resilience is inbuilt in their species through adaptations over time to these regular events. There are three important concepts related to resilience in hbr review Moreton Hall School, ecosystems- elasticity, malleability and amplitude. Elasticity is the rate of recovery of an ecosystem after stress. Malleability in an ecosystem is the difference between the critical thinking text st. clair college, final recovery level and the level of the pre-stress period. The greater the malleability, the less the ecosystem’s resilience. The lower the sample of academic writing essay curtin university singapore, malleability, the greater the ecosystem’s resilience. Amplitude is the threshold level of change that prevents an ecosystem from recovering to hbr review Moreton Hall School its original level. If natural stress occurs slowly, ecosystems can adapt. Sudden natural disasters can destroy ecosystems. Depending on the severity, ecosystems may take a long time to hbr review Moreton Hall School recover. Climatic changes that occur over millions of years, allow plants and animals that are more suited to change to survive, breed and how to write reflective essay les roches marbella international school of hotel management, pass on their favorable characteristics to new generations. Those unsuited to change die out. hbr review Moreton Hall School. This process is called natural selection, e.g. the Wollemi pine once covered a vast area of Australia. As climate changed it gradually died out until it is hbr review Moreton Hall School, now found naturally in only one valley in the Blue Mountains of Australia. Examples of catastrophic rates of stress: Examples of gradual rates of stress: Adaptation, evolution. Climatic changes. Disease. Ecological succession. Immigration. Ecosystems and the communities within them are constantly responding to environmental changes, either catastrophic or gradual. The gradual change in the composition and function of communities, especially plants, is called ecological succession. There are two types of ecological succession. Primary succession occurs when there has been a catastrophic change such as a volcanic explosion, lava flow, mud flow, or glacial retreat, where all the topsoil has been removed. The establishment of vegetation and soil on the bare rock over a period of writing analytical essay les roches jin jiang international hotel management college, hundreds of years. Secondary succession occurs in an area where the natural vegetation has been altered, disturbed, removed or destroyed. Abandoned farmland, forests affected by fire or logging and heavily polluted streams are good examples. The soil remains intact and pioneer species such as weeds and grasses prepare the hbr review Moreton Hall School, way for other species, possibly larger trees and shrubs, depending on the environmental conditions and hbr review Moreton Hall School, the nature of the surrounding ecosystems. Mt St Helens eruption: an example of natural stress. The Mt St Helens eruption shows how resilient ecosystems are to natural stress. hbr review Moreton Hall School. In the case of Mt St Helens, the effects on the surrounding ecosystem were devastating. 120m of summit vanished, leaving in its place a crater 2km wide, 4km long and how to write reflective essay les roches marbella international school of hotel management, 1.5km deep. 380km2 of land to the north of the mountain was devastated by the blast and covered by hbr review Moreton Hall School, hot volcanic debris. large areas of coniferous forest were destroyed and critical thinking text st. clair college, countless numbers of hbr review Moreton Hall School, animals were killed. Volcanic ash, carried by the hbr review Moreton Hall School, prevailing winds, was spread 1500km to the west. 100 people lost their lives. Within just a few years of the eruption scientists found that pioneering flora and fauna was staring to colonize the hbr review Moreton Hall School, ash grey volcanic landscape. Plants such as lupin, Indian paintbrush, pearly everlasting, and fire weed took root amongst the coarse grey rock. Willow and elder trees had grown to the height of 1.2m. The roots of decaying leaves and stems of the vegetation provided the organic material needed to convert volcanic grit into sustaining soil. By activities that humans partake in, in order to produce their food, goods and services, ecosystems are disturbed. There have been 3 major surges in the human population, always related to some kind of change in technology. The first was associated to the breakthrough in weapons technology. The invention of the throwing stick increased the supply of essays writing in english institut montana zugerberg, food and moved humans up the trophic level. The second was when people settled down and sample of academic writing essay curtin university singapore, domesticated certain animals and plants. The standard of living increased and farming had a major impact on the land. The third surge was technologically based. hbr review Moreton Hall School. Technology has been used to greatly increase food supplies and combat disease. A-g requirements for high school Montverde Academy. Rapid growth placed stresses on all aspects of ecosystems. The modification of ecosystems results in hbr review Moreton Hall School, the simplification of the ecosystem and eventual breakdown. Impacts of modification. Impacts of modification: Changes the energy flows, biogeochemical cycling and nutrient cycling. Leads to the eventual destruction of the ecosystem or parts of it without regeneration Can cause global environmental crises. Humans have been interacting with ecosystems and modifying them for as long as human life has existed on Earth. But the scale, speed and degree of change that is now occurring threatens the survival and integrity of many ecosystems and indeed of human life. The impacts of human-induced modifications to ecosystems in a-g requirements for high school montverde academy, modern times have been increased in the following ways: The speed at which humans can change ecosystems has never been greater. hbr review Moreton Hall School. The scale of ecosystem change humans are capable of has never been larger, extending to the global level. The technology to implement large-scale changes efficiently to ecosystems is accelerating. The Earth’s human population is continuing to grow at an alarming rate, placing even greater pressure on ecosystems. Examples of catastrophic rates of human-induced change: Change to stream course. Deforestation. Critical thinking courses Clifton College. Erosion. hbr review Moreton Hall School. Fire. Loss and degradation of wildlife habitat. Mining. Overgrazing. Pesticide application. Ploughing. Toxic contamination. Urbanization. Water and essays writing in english institut montana zugerberg, air pollution. Examples of gradual rates of human induced change: Depletion of groundwater. Elimination of ‘pests’ and writing analytical essay les roches jin jiang international hotel management college, predators. Excessive tourism. Introduction of exotic species. Loss and degradation of wildlife habitat. Over hunting and overfishing. Salinisation and waterlogging of solis from irrigation. Soil compaction. Toxic contamination. hbr review Moreton Hall School. Urbanisation. Water and air pollution. How to write reflective essay Les Roches Marbella International School of Hotel Management. Types of modification. Types of modification: Physical control Habitat control Biological control Chemical control Water Cycle control. Humans have modified natural ecosystems in many ways. It is possible to classify these as intentional or unintentional, but the distinction is not always clear. An example of an intentional modification to hbr review Moreton Hall School ecosystems would be the a-g requirements for high school montverde academy, construction of a dam on a river. The unintentional changes that could result might be the a-g requirements for high school montverde academy, extinction of some species that needed shallow water to survive. There are six major ways humans have changed natural ecosystems. Ecosystems are destroyed, degraded and simplified. hbr review Moreton Hall School. Agricultural land use often requires the wholesale clearing of land to grow single crops or graze animals. This monoculture system simplifies the complex interrelationships existing in hbr review Moreton Hall School, natural ecosystems and is maintained through pesticides and fertilizers. Urban land creates greatly modified ecosystems. Pest populations have become stronger. To maintain monocultures, pesticides and herbicides need to sample of academic writing essay curtin university singapore be applied to keep crops safe from damage. Through natural selection, insects and unwanted plants can quickly develop resistance to pesticides and herbicides. Predators are eliminated. Any species that may be a threat to domesticated animals, either through direct competition for critical thinking courses clifton college grass or through preying are usually eliminated. The Tasmanian tiger was exterminated because it was seen as a threat to sheep. Alien species are introduced. The introduction of alien species can be intentional, such as the introduction of foxes and sample of academic writing essay curtin university singapore, rabbits into Australia, or unintentional, such as the release of marine organisms like the North Pacific sea star into Australian waters through ballast water. These foreign species can have a devastating impacts on natural ecosystems where they usually have no predators. They also have sever economic costs because of the cost prevention measures and loss of production. Potentially renewable resources are over harvested. Overgrazing of hbr review Moreton Hall School, grasslands can lead to desertification, where the ecosystem becomes degraded and the vegetation and soils are depleted. These marginal ecosystems can be transformed into semi-desert or desert and suffer sever damage. Fisheries are no exception and how to write reflective essay les roches marbella international school of hotel management, there have been several collapses of fisheries that had been pushed beyond their resilience. Chemical cycling and energy flows are interfered with. A simple monoculture is an abnormal system compared with a natural ecosystem. Vast quantities of fertilizers, herbicides and pesticides are required to sustain the yields of the crops. The runoff pollutes streams, lakes and oceans and causes changes in their ecosystems. The natural chemical cycling and energy flows are disrupted. Energy and matter is captured, transferred and lost as it flows between the various biotic and abiotic components of an ecosystem. At each stage, heat is lost or given off. On a global level, human modification of hbr review Moreton Hall School, energy flows in ecosystems can change entire biomes. The enhanced greenhouse effect may lead to increased surface. temperatures and this will change climates over the long term. Some areas may experience increased rainfall while others may experience decreased rainfall. The nature of the changes is fairly unpredictable and scientists disagree as to what the impacts will be. Natural energy flows are disrupted in urban areas through the creation of hbr review Moreton Hall School, large heat islands and dust domes. The heat island around urban areas causes wind circulation patterns that create a trapped dust dome of suspended pollutants above the urban areas. Winds may move this dome away and form a dust plume spreading the city’s pollution many kilometres away. Natural ecosystems have several nutrient cycles operating in them. hbr review Moreton Hall School. These cycles continuously move the elements and compounds from the abiotic environment to the biotic environment and back. They are driven by solar energy and gravity and include the: The Carbon cycle. The Nitrogen cycle. The Oxygen cycle. The Phosphorus cycle. Critical thinking text St. Clair College. The Hydrological cycle. Human-induced changes in one ecosystem usually have cascading and unpredictable effects on other inter-related ecosystems through these nutrient cycles. Human-induced modifications to nutrient cycles are numerous and critical thinking text st. clair college, vary in scale from local to global. The clearing and removal of timber from hbr review Moreton Hall School a rainforest disrupts the nutrient cycle in these low-fertility ecosystems. The apparent richness of the rainforest ecosystem is a result of the recycling of nutrients stored in the trees and leaves. hbr review Moreton Hall School. The soils are typically shallow and leached because of heavy rainfall. Writing analytical essay Les Roches Jin Jiang International Hotel Management College. If the timber is removed, the nutrients are not recycled and the soil is not replenished. In addition, once the protection offered by the trees and hbr review Moreton Hall School, their root systems is a-g requirements for high school montverde academy, removed, rapid erosion occurs, removing the shallow topsoil and how to write reflective essay les roches marbella international school of hotel management, making regeneration of the rainforest a long, slow process that may take centuries, if It is allowed to happen. Ecosystems have six key features that determine the relationships between their biophysical components: Interdependence Diversity. Resilience Adaptability (the ability of an organism to adapt to changes in hbr review Moreton Hall School, its environment. Unpredictability (could include things like genetic evolution and climatic change). Critical thinking text St. Clair College. Limits (set by abiotic and biotic factors). Humans simplify ecosystems and attempt to control them for their own purposes. There are many complex inter-relationships between biophysical components in. natural ecosystems that are disrupted through human activities. Some of these disruptions create feedback loops that adversely affect human activities. hbr review Moreton Hall School. If crocodiles were not protected in Australia, for example, their role as a keystone species would be threatened. When hunting of crocodiles was permitted, the saltwater species was on the brink of extinction. Since protection, their numbers have built up to pre-hunting levels and the estuarine ecosystems where they live are more in balance. Ecosystems rich in diversity generally have greater resilience and are, as a result, able to hbr review Moreton Hall School recover more readily from naturally induced stress, such as drought and fire, and human-induced habitat degradation. Where diversity is diminished, the functioning of ecosystems (and by association the wellbeing of hbr review Moreton Hall School, people) is put as risk. Biological diversity or biodiversity covers 3 areas: Genetic diversity. Species diversity. Difference in Ecology Genetic diversity. Genetic diversity is the variety of critical thinking courses clifton college, genetic material contained in all individual plants, animals and micro-organisms Ecosystems rich in genetic diversity generally have greater resilience and therefore are able to hbr review Moreton Hall School recover more readily from natural and human stresses. Where diversity is low, ecosystem functioning is often at risk. Communities of plants and/or animals with high levels of genetic diversity often survive periods of stress because some of a-g requirements for high school montverde academy, the organisms are usually not affected by the change. The living organisms pass on their favorable genetic traits to their offspring. In this way species over time adapt to change. This is called natural selection. Ecologists say that of critical thinking courses clifton college, an estimated 5.3 million species currently inhabiting the planet, over 1.4 have been identified. hbr review Moreton Hall School. Evolutionary extinction (i.e. natural extinction) accounts for the loss of about one species/year. hbr review Moreton Hall School. The actual extinction rate is now estimated at one/day. This reflects the impacts of human. Diversity high → greater resilience We kill species → ecosystem cannot withstand natural & human stress. Genetic diversity is the variability in the genetic components among individuals of a single species. If a number of individuals are limited, then the genetic diversity is limited and the species is more likely to be vulnerable to extinction. About 80 northern hairy-nosed wombats, for hbr review Moreton Hall School example, live in one 300-hectare site in Epping Forest National Park in central QLD. There are no others in existence. Is a disaster struck this small population, the genetic diversity would be further be reduced and inbreeding could occur. Sample of academic writing essay Curtin University Singapore. The genetic pool needs to be wide so there is a greater chance of the species surviving. Species diversity describes the variety of species in different habitats. Is a species is lost through extinction, then the species diversity of the ecosystem suffers. hbr review Moreton Hall School. Species diversity varies through time and over different geographical areas. For example, the Great Barrier Reef has around 2,000 fish species and around 500 coral species compared with 100 fish species and 300 coral species in the coral reefs around New Caledonia. The variety of biological communities that interact with each other and their non-living environment is called ecological diversity. Scientists admit that they have not found and identified many of the world’s species. Ecologists say that of the estimated 5-30 million species that currently inhabit the planet only 1.4 million have been identified. These represent only 10% of the species that have ever existed on earth. The other 90% have fallen victim to an hbr review Moreton Hall School, evolutionary process of natural extinction. why biodiversity should be maintained untapped resource. Biodiversity is an untapped resource. We do not know what species may be useful to humans in the future as a source of medicine, food and other human needs. There is economic potential yet to be realised. ecologically sustainable development. We need the variety of living resources for hbr review Moreton Hall School ecologically sustainable development. insurance policy against disaster. A variety of genetic material is an insurance policy against disaster. This is essays writing in english institut montana zugerberg, concerning the usefulness of ecosystems in monetary terms:- Recent study estimated that total value of goods and services provided by the earth’s ecosystems is US$33 trillion. There is an enormous variety of products obtained from ecosystems:- Rattan (wild vine in SE Asian forests) – cane furniture and other products. Critical thinking text St. Clair College. Generates $2.7 billion in exports/year. US Coastal fishing industry valued at US$3.3 billion in 1991. Rubber & tropical fruits (Amazon rainforest) – net economic value of US$7000/hectare w/o harming the forest. If the same area is cleared however, 94m³ of timber produced. In 1992, an estimate of medicines derived from natural sources, came to US$40 billion/yr worldwide. Tribes in Peru were found to use plants to treat skin disorders, tuberculosis, fevers, animal bites, infertility, kidney disorders, wounds, burns, tooth decay. Ecosystems with a high utility value include: Mangroves Forests Swamps Floodplains Natural marshes. All the critical thinking text st. clair college, living and non-living components of the earth’s ecosphere have either an existing or potential utility value or usefulness. By maintaining and protecting ecosystems we maximise humanity’s ability to adapt to change. The sheer diversity of life represents a vast store of genetic material that can be tapped as human needs change. The loss of a species- whether plant, animal, fungus, bacterium or virus- denies humanity a possible future source of food, medicine, chemicals, fibres and other materials. hbr review Moreton Hall School. Australia’s flora and fauna, for example, make a substantial contribution to the national economy through forestry, the pastoral industry, fisheries, tourism, land reclamation, beekeeping, wildflower harvesting and the kangaroo trade. Ata global scale, components of the various ecosystems play a vital role in protecting catchments, purifying water, regulating temperature, regenerating soil, recycling nutrients and wastes, and maintaining the quality of air. Their protection is critical to the physical wellbeing of humanity. Almost all of the important food crops are native to hbr review Moreton Hall School environments at risk in the developing world: for example wheat is from Afghanistan, potatoes from the highlands of hbr review Moreton Hall School, Peru, and sorghum and coffee from how to write reflective essay les roches marbella international school of hotel management Ethiopia and Sudan. Critical thinking text St. Clair College. It is to these regions, to the wild relatives of the crop plants of the traditional varieties grown by subsistence farmers, which the plant breeders have to turn to for their genetic material. This vital resource can only be maintained by preserving the environments in which the a-g requirements for high school montverde academy, wild species grow, and by making it worthwhile for poor farmers to continue growing their traditional varieties instead of changing to modern higher-yielding strains. In the highly competitive ecosystems, such as tropical rainforests, many organisms depend on writing analytical essay les roches jin jiang international hotel management college, chemically based protective mechanisms for their own survival. These naturally produced chemicals constitute a major pharmacological resource. The loss of an even a small area of hbr review Moreton Hall School, rainforest could therefore mean the loss of disease-conquering chemical compounds. Medical scientists have estimated that they have managed to examine only about 5,000 of the estimated 250,000 plants that have pharmacological value. The vine Tylopora is hbr review Moreton Hall School, a source of drug tyocrebrine, which has been effective in hbr review Moreton Hall School, treating lymphoid leukemia. In a world where almost everything is measured in terms of its monetary value it is how to write reflective essay les roches marbella international school of hotel management, not surprising that some economists should attempt to value ecosystems in terms of what people are prepared to pay either to hbr review Moreton Hall School consume them or preserve them. Sample of academic writing essay Curtin University Singapore. The existence value of an ecosystem is defined as the hbr review Moreton Hall School, value of a community is hbr review Moreton Hall School, prepared to place on an ecosystem in its natural state. Many national parks, for example, occupy areas that could otherwise be used for hbr review Moreton Hall School farming or urban development. They also contain resources, such as timber and minerals, which could be exploited. The amount that people would be willing to hbr review Moreton Hall School pay for the land plus the cost of maintaining the hbr review Moreton Hall School, parks is known as its existence value. The community, through government authorities, must be prepared to accept the cost. Writing analytical essay Les Roches Jin Jiang International Hotel Management College. Given that ecosystems have an hbr review Moreton Hall School, economic value it follows that they also have an option value. The option value is the cost of keeping the how to write reflective essay les roches marbella international school of hotel management, ecosystem or species in its natural state as opposed to exploiting its resources. Another benefit to be derived from the protection of ecosystems is the avoidance of the costs of inaction. Environmental degradation diminishes the productive capacity of the land. This not only essays writing in english institut montana zugerberg, incurs an economic cost but also diverts resources from other social priorities to the repair of environmental degradation. Exploiting the utility value of ecosystems would, if taken to its extreme, destroy the environment. Utility value, in a practical context, should incorporate appropriate management techniques so as to minimise the risk of environmental degradation. Intrinsic having value in existing alone as a natural phenomenon Ecosystems are priceless and precious. ‘Intrinsic value’ is used to signal amenity value – the value in providing pleasure, enrichment and satisfaction. Most ecosystems are inherently useful and frequently are regarded by economists as natural capital to how to write reflective essay les roches marbella international school of hotel management become useful at some time in the future. hbr review Moreton Hall School. Many different religions’ theologies include an intrinsic value for nature, e.g. Jainism and Buddhism see all creatures as part of a suffering world. Ecosystems are endowed with their own intrinsic and ethical value, that is, they have the essays writing in english institut montana zugerberg, right to exist irrespective of their utility value. While few would disagree with such a sentiment, and most people would support the hbr review Moreton Hall School, view that we need to protect ecosystems for the benefit of future generations, there is still no. generally agreed mechanism or strategy by which this could be achieved. Central to the notion of hbr review Moreton Hall School, the intrinsic value of ecosystems is a recognition that the biophysical environment provides for many of the inspirational, aesthetic and spiritual needs of people. In an increasingly urban society, aesthetic values, for example, make an important contribution to emotional and spiritual well being. By interacting with elements of ecosystems, humans are reminded that they are part of an interdependent natural world. The aesthetic qualities o ecosystems are also valued for their recreational potential. Essays writing in english Institut Montana Zugerberg. Activities such as photography, trekking, bush walking, bird watching and field studies draw heavily on the aesthetic qualities of the biophysical environment. The growth of ecotourism is critical thinking text st. clair college, closely linked to the growing appreciation of the aesthetic and ecological qualities of environments. The intrinsic value taken to its extreme would mean that no, or minimal, human uses would take place in an ecosystem. This option would assist the hbr review Moreton Hall School, long-term survival of essays writing in english institut montana zugerberg, the ecosystem due to the removal of how to write reflective essay les roches marbella international school of hotel management, direct human-induced change to the ecosystem that would risk degradation of its features. An area set aside for its intrinsic value, however, may experience problems from adjacent land use leading to the indirect human-induced change, and problems from lack of public support due to the lack of familiarization with the site caused by lack of utilization. In a practical context, protection of an area may involve acknowledging its intrinsic value but managing it with a utility value for social, political and economic reasons, or may require extensive public education campaigns to increase public awareness and support. Heritage protection of areas seen as having outstanding universal value. In Australia, the Royal National Park was dedicated as an area of outstanding heritage as early as 1879. The latter half of the 20th century saw the emergence of great concern for the heritage value of ecosystems. The UN formed an important organization – the World Conservation Union (IUCN). The IUCN is a network of governments. The Australian heritage Commission views natural heritage, worthy of National Estate listing, to hbr review Moreton Hall School include ‘those places, being components of the natural environment of Australia or the critical thinking courses clifton college, cultural environment of Australia, that have aesthetic, historic, scientific or social significance or other special value for future generations, as well as for the present community’. Critical thinking text St. Clair College. In Australia, the hbr review Moreton Hall School, concept of ‘natural heritage’ is wide enough to encompass both large areas of pristine wilderness and those sites more readily accessible to humans. Education has played a critical role in developing public support for heritage listing. As support has grown, additional sites (particularly those close to human settlements) have been added to the hbr review Moreton Hall School, list. In some cases, listing was granted after a public controversy arising from a development proposal that would have degraded the heritage value of an ecosystem. Current Australian World Heritage Areas: Great Barrier Reef, Kakadu National Park, Ulura-Kata Tjuta National Park, Fraser Island. Ecosystems are continually changing and hbr review Moreton Hall School, evolving. If we don’t allow this to occur naturally then ecosystems can be damaged and the quality of human life can be affected (dropped). Overloading Australian rivers with nutrients = blue green algae blooms = lower utility value and hbr review Moreton Hall School, degraded ecosystem Increase saline water tables = changing ecosystems quickly = plants can’t adapt Global warming = increase temperature of water = coral bleaching = natural change can’t proceed The loss of crucial species may have unforeseen consequences and therefore must maintain species if natural change is to occur. We must learn from the past to protect the hbr review Moreton Hall School, future. The most valuable earth based ecosystems, estimated at US$4.9 trillion, are wetlands – mangroves, forests, swamps, floodplains & natural marshes. The most important role these wetlands have is in controlling floods, storm protection and cycling both nutrients and waste. Wetlands in hbr review Moreton Hall School, Australia’s high country are at risk through the hbr review Moreton Hall School, trampling of stock and the impact of the heavy tread of bush walkers. The upland wetlands act as sponges, slowly releasing water through the hbr review Moreton Hall School, catchment during dry periods. The health and hbr review Moreton Hall School, integrity of these ecosystems needs to be maintained. Human alteration of water flowing through catchments has increased the rate of flow, destroyed soil resources and hbr review Moreton Hall School, exacerbated floods and droughts. In far too many locations around the world, there is evidence of disruption to a-g requirements for high school montverde academy nutrient cycling. Rather than allow natural change to proceed unhindered, many ecosystems are overloaded with nutrients. Rising saline water tables, dryland salinity and spreading acid sulphate soils are all Australian examples of interfering with natural changes and preventing natural change from proceeding unhindered. The multiplicity of life forms on how to write reflective essay les roches marbella international school of hotel management, earth is a product of ongoing evolutionary process. Many ecologists and environmentalists argue that humans have an ethical responsibility, and a-g requirements for high school montverde academy, selfish rationale, to see that this evolutionary process continues relatively unimpeded. To ensure that this occurs it will be necessary to protect large areas of hbr review Moreton Hall School, representative ecosystems. Essays writing in english Institut Montana Zugerberg. To achieve the desired objectives these areas should: Be large enough to protect and conserve intact ecosystems effectively and to allow evolutionary processes to continue. The areas must have representative biodiversity- small fragmented areas often lack biodiversity. Boundaries need to be environmentally based and cross-national if possible – bilateral agreements need to put the ecosystem before political considerations. Sample of academic writing essay Curtin University Singapore. Local people need to hbr review Moreton Hall School be integrated into the management program so the benefits are shared in their communities. The local economy should benefit, not suffer, from the protection of hbr review Moreton Hall School, the ecosystem. The knowledge of hbr review Moreton Hall School, the local people should be used as part of the management strategy. Ideally, the surrounding areas need to hbr review Moreton Hall School have a buffer zone that allows for migration patterns of animals and regeneration of species. The reserves need to be well managed and adequately funded. hbr review Moreton Hall School. Rangers need to critical thinking text st. clair college ensure that the hbr review Moreton Hall School, animals are protected from the people outside the area and a-g requirements for high school montverde academy, that the people are protected from the animals within the area. In 2000, South Africa’s Kalahari Gemsbok National Park and Botswana’s Gemsbok National Park were united to hbr review Moreton Hall School form Kgalagadi Transfrontier Park. Sample of academic writing essay Curtin University Singapore. The new 3.8-million-hectare park is managed as a single ecosystem and allows free movement of animals and people around the park. This park is southern Africa’s first ‘peace park’, established as much to foster goodwill between nations as to hbr review Moreton Hall School increase the how to write reflective essay les roches marbella international school of hotel management, viability and size of essays writing in english institut montana zugerberg, conservation reserves. Success can only be measured over a long period of time to ensure changes are not just part of normal ecosystem fluctuations. Some objective measures include species numbers and stability of population based on reliable benchmarks. Lack of benchmarks can be overcome by undertaking an environmental audit: measuring key aspects of hbr review Moreton Hall School, environment quality. This can be used to evaluate the success of management practices. Success needs to be judged in terms of sustainability. Components of writing analytical essay les roches jin jiang international hotel management college, Ecosystem Management. The Committee on hbr review Moreton Hall School, Ecosystem Management of the Ecological Society of America identified eight elements for ecosystem management. hbr review Moreton Hall School. They are: Clear operational goals. Sound ecological models and understanding. An understanding of complexity and interconnectedness. Recognition of the dynamic character of ecosystems. Acknowledgement of ignorance and uncertainty. Commitment to adaptability and accountability. Acknowledgement of humans as ecosystem components. Most contemporary management strategies rely on the principles of ecologically sustainable development. Some of the concepts involved in ecologically sustainable development are listed below. Intra-generational equity/Ensuring social equity. all people have the right to benefit from the worlds resources. present generations shouldn’t use resources in such a way that future generations are in a worse position. We have an obligation to ensure ecosystems are healthy, diverse and productive. Maintaining natural capital Limiting use of natural resources The precautionary approach. where there is hbr review Moreton Hall School any doubt about using a resource, don’t do it. Planning for qualitative development Pricing Biological diversity. it is essential for the evolution and maintenance of ecosystems. The habitat and species are totally protected from human activity of any kind. e.g.: GBR & some wilderness areas. There are three alternative management approaches to wildlife. They are: Species approach – laws aimed at protecting endangered species, such as Australia’s Endangered Species Act. Ecosystem approach – this is the most effective as it aims to preserve viable populations in their natural habitat. Wildlife management approach – this is where humans make use of writing analytical essay les roches jin jiang international hotel management college, the wildlife either through ecotourism as in the African game parks or through hunting as in many of the North American parks. The aims of managing wildlife are to: Manipulate wildlife populations and their environments for their survival and for human benefit (sustained yield). Preserve endangered and threatened species. Enforce wildlife laws. Conservation. There is limited impact on ecosystems through sustainable use of resources. There are around 9,000 conservation reserves around the world, protecting about 6% of the land area on hbr review Moreton Hall School, earth. Scientists believe a minimum of 10% of the land area of the Earth needs to be protected to conserve ecosystems, their biodiversity and integrity from human activities. Some developing countries have very little of their land protected. In recent years, some developed countries created debt-for-nature swaps with developing countries. hbr review Moreton Hall School. Under this system, some of the country’s debt is written off in exchange for the establishment of protected reserves in areas of high conservation need. Successful debt-for-nature reserves have been established in countries like Costa Rica and Colombia. Selecting a Reserve Site. The major priority in selecting a site for a reserve is writing analytical essay les roches jin jiang international hotel management college, to protect fragile ecosystems under threat. Some of these take thousands of years to form and can never be recreated if lost. The following factors should be taken into account when choosing a site: The diversity of species present. The diversity of habitats available. hbr review Moreton Hall School. The degree to which an hbr review Moreton Hall School, area is influenced by human activity. The size, shape and hbr review Moreton Hall School, proximity to other protected areas. The availability of corridors between reserves to encourage movement of species and greater genetic variation. In an ideal world, management strategies would select the hbr review Moreton Hall School, best combination of writing analytical essay les roches jin jiang international hotel management college, these factors to preserve the a-g requirements for high school montverde academy, ecosystems at hbr review Moreton Hall School, risk. In reality, however, the choice of site is often limited to what is available after other human demands have been satisfied. How to write reflective essay Les Roches Marbella International School of Hotel Management. This compromise puts ecosystems at risk under further pressure. Size and Shape of Conservation Areas. Ecologists have found that the shape and hbr review Moreton Hall School, size of nature reserves and hbr review Moreton Hall School, the proximity to other protected areas largely determines their success. Reserves are like islands of habitat surrounded by human-modified ecosystems.