In recent years large-scale conversions of land use have been taking place worldwide to sustain the ever-growing population. As a result, parameters such as vegetation type, air temperature, relative humidity, soil moisture, and movement of the wind have been markedly affected. Many studies have examined the impact of urbanisation on temperature or relative humidity, but few have explored whether or not potential evapotranspiration (PET) is influenced by changes in population density and urbanisation. In this context, in the present study we attempted to find answers to three key questions. Is there a relationship between PET and urbanisation? If so, which parameter, able to change the pattern of PET, is the most sensitive to urbanisation in a given region? Lastly, can the impact of urbanisation on PET be measured without the application of any of the subjective models currently available and used worldwide to solve similar problems? Through analysing the recent literature, we found that a distinct relationship does indeed exist between PET and urbanisation. The most important parameter affected by urbanisation that also influences PET was investigated by the application of multi-criteria decision-making, and this was found to be air temperature. Finally, a neurogenetic model was applied to reveal the vulnerability of evapo-transpiration to urbanisation in four cities with differing levels of population density. The results confirmed that the vulnerability is greater in cities with denser populations and greater levels of urbanisation.
1. Introduction
More than 50% of the world’s people live in cities, and the urban population is growing at a much faster rate than the Earth’s population as a whole and by larger annual increments t...
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... population density.Furthermore, according to Buyantuyev and Wu(2012), “urbanization transforms vegetation patterns and ecosystem processes which are controlled primarily by climate in desert regions”.
Therefore, from the above-mentioned studies, we can see that the majority of the factors that influence PET are also affected by changes in urbanisation. Taking this finding one step further, we were interested in establishing the most important parameter influenced by urbanisationthat also causes the greatest rate of change in PET. A multi-criteria decision-making (MCDM)and artificial neural network (ANN) approach was used to achieve this aim. After first introducing MCDM and ANNs in more detail in section 2, as well as the specific methodology of the study,the results and discussion are presented in section 3.Finally, theconclusionof the study is given in section 4.
Some Abiotic features include Cold Climate, Rain, Snowfall, Snow Covered Ground, Snow, Sun, Ice, Water, Strong Winds, Short Days in the Summer, Very Cold and Long Days in the Winter, Minerals, Temperature, Carbon Dioxide, Air, Little Rainfall, Poor Soil.
The ecology of these ecosystems plays a key role in mediating many of the functions of dunes, including their growth and stabilization. Similarly, the physical environment of this unique habitat strongly shapes the ecology of the organisms living there.
D. Effect of Human Presence- The desert biome is a highly sensitive biome in that it takes longer to recover from disturbances. Activities like off road driving as well as cattle and collection of firewood destroy the desserts natural habitat leading to reduce number of certain
Urban change that will benefit the greatest number of people will require a change in how we view the world. For these urban changes to occur, we need larger structural changes in how we conduct business and how political decisions are made.
Plants that are grown in urbanized environments are typically more exposed to the pollutants that accompany them. These pollutants include CO2, NO2¬, and higher temperatures versus plants in rural areas1. Furthermore; urbanized environments have been known to affect the net primary production of plant species in a negative fashion2. The basis of the experiment revolves around the fact that urbanized environments have
Population density is the total number of people per unit of area, usually per square mile. As population density rises to high levels, as it has in today’s cities, the familiar problems of urban living appear, including high rates of crime and homelessness.Interacting with these problems are crises of the physical environment, such as air and water pollution and the growing output of hazardous wastes with the resultant global warming. ” Ten Years from now,India will have an extra 250 million people. In five of the worlds “hot spots” of water d...
The Mojave Desert it affected by air pollution and invasive plant species which are a cause to many wildfires.
Although Canadians have a good reason to become designers of their own urban future, there are many leading negative effects on the environment. In fact, most of Canada’s population growth in recent years has been concentrated on four regions: British Columbia’s Lower Mainland and southern Vancouver Island; the Edmonton-Calgary corridor; Toronto’s Golden Horseshoe region; and the Greater Montreal area. Despite the fact that there was virtually no growth in the rest of the country between 1996 and 2001, the population of these four regions (where 51 per cent of Canadians now live) grew 7.6 per cent. The rate at which land was urbanized in these regions was even greater, sometimes double or more the population growth rate. This difference between the growth rates of people and the land they occupied defines urban
A general situation of urbanization trend in developing countries and developed countries is increasing. In 18th Century only 3% of the world total population lived in urban areas but as projected in 2000 this number will increase at above 50% (UN as cited in Elliot, 1999, p. 144). According to UN (as cited in Elliot, 1999, p.144), it is figured that the total urban population in developing countries has increased from approximately 400 millions people in 1950 to approximately 2000 millions people in 2000. At the same time, total urban population in developed countries is double...
In 1950, only 13% of China’s population lived in cities (Seto, n.d.). Post 30 years, one hundred-million people moved to large cities from rural areas in China. This migration was considered the largest migration in human history. To compare this migration to western cities, the example of Shenzhen is used. For a Western city to have a population of three million to increase to ten million, it takes about a hundred years. 30-year old city, Shenzhen on the other hand made this population increase in just a decade (qtd. Caughey and Dawn). Today, over 53.7% of its population lives in cities; by 2020 it is projected that a whole 60% of the population will live in cities (Xinhuanet, 2014).
The Negative Effects of Urbanization on People and their Environment As our world becomes increasingly globalized, numerous people travel to urban areas in search of economic prosperity. As a consequence of this, cities in periphery countries expand at rates of 4 to 7 percent annually. Many cities offer entrepreneurs the potential for resources, labor, and resources. With prosperity, cities also allow the freedom of a diversity of ways of life and manners (Knox & Marston, 2012). However, in the quest to be prosperous, increasing burdens are placed on our health and the condition of our environment.
Selecting the appropriate variables must also be considered, while taking into consideration the relevant information gained from the background information, and results from trial experiments. Biological Knowledge The following biological knowledge is all directly related to this investigation and is essential for predicting trends, and being able to give some sort of explanations for what is seen. Community Ecology And Succession A community is a group of interacting populations living in any given area representing the living part of an ecosystem.
First of all, overpopulation drastically affects the land. Possibly the most prominent example of the depreciating health and amount of land is the need for developments. Due to the exploding population in the United States, about 1.2 million acres of land every year is being converted to subdivisions, malls, workplaces, roads, parking lots, resorts, and many other developments (“Overpopulation,” Internet). That is a substantial amount of land being overturned to satisfy human desires. To put it in better perspective, between 1982 and 1997, the land mass lost to development is equal to the size of Maine and New Hampshire combined, which is approximately 25 million acres (“Overpopulation,” Internet). While soil is being ruptured for human preference, the number of cities has remarkably modified. In 1975, Mexico City, Tokyo, and New York City were the only cities considered as megacities (“Special,” Internet). In today’s world, that number is considerably small. Now, there are 21 megacities in the world. A megacity is when the population of that city becomes greater than 10 million people (“Special,” Internet). Therefore, the 21 megacities that are currently in the world holds more than 21...
Surely there exist cities that are determined to transform into more eco-friendly representatives of urban civilization, yet these efforts are typically focused on minimizing the harmful output of cities rather than rew...
Global cities are cities with substantial economic power, controlling the concentration and accumulation of capital and global investments. Despite this, global cities are the sites of increasing disparities in occupation and income. This is as a result of large in-migration and growing income inequality together with capacity and resource constraints, and inadequate Government policies.