At all stages of its development man was closely connected with the outside world. But since appeared highly industrialized society, dangerous human interference in nature has increased dramatically and so now threatens to become a global threat to humanity. Consumption of non-renewable raw materials increases, more and more arable land is withdrawn from the economy, so they built cities and factories. All a person has to intervene in the economy more than the biosphere - that part of the world where there is life. Earth's biosphere is currently undergoing the growing human impact. It is possible to identify some of the most important processes, each of which does not improve the ecological situation on the planet.City and weThe most extensive and significant is the chemical pollution it improper substances of chemical nature. Among them - the gaseous and particulate pollutants of industrial and domestic origin. Progresses and the accumulation of carbon dioxide in the atmosphere. Further development of this process will intensify unwanted upward trend in the average temperature of the planet. There is no doubt the value of the chemical contamination of soil with pesticides and increased acidity, leading to the collapse of the ecosystem. In general, all factors considered, which can be attributed to contaminating effect, exert a significant influence on the processes occurring in the biosphere. All this is especially pronounced in large cities, and not only where a negative impact on the environment took catastrophic proportions.City and weUrban environmental problems, especially the largest ones, are associated with excessive concentration on relatively small areas of population, transport and industrial enterprises, with the formation of anthropogenic landscapes, very far from a state of ecological balance.The growth rate of the world's population was 1.5-2.0 times lower than the growth of the urban population, which today is 40% of people in the world. During the period 1978 - 2008 years. the population of large cities increased by 4, in the middle - in 3 and small - in 2 times.Socio-economic situation has led to lack of control of the process of urbanization in many countries. The percentage of urban population in some countries is: Argentina - 83, Uruguay - 82, Australia - 75, USA - 80, Japan - 76, Germany - 90, Sweden - 83. In addition to the major cities of millionaires are growing rapidly urban agglomerations or merged city. These are the Washington-Boston and Los Angeles-San Francisco in the United States; cities of the Ruhr in Germany; Moscow, Donbass and Kuzbass in the CIS.City and weOver major cities atmosphere contains 10 times more aerosols and 25 times more gas. In this case, 60-70% of gas pollution gives road transport. Stronger condensation precipitation increases by 5-10%. Self-purification of the atmosphere prevents the reduction of 10-20% of solar radiation and wind speed.City and weCities consume more than 10 times more water per 1 person than rural areas, and water pollution reaches catastrophic proportions. Volumes of wastewater reaching 1m2 per day per person. Therefore, almost all the major cities are experiencing water shortages, and many of them get water from distant sources.Aquifers under the city was badly depleted as a result of continuous pumping wells and wells, and also contaminated to a considerable depth.City and weUndergoes a radical transformation and soil cover urban areas. Large areas, under highways and neighborhoods, it is physically destroyed, and in the areas of recreation - parks, gardens, yards - much destroyed, polluted household waste, hazardous substances from the atmosphere, enriched by heavy metals, bare soil contributes to water and wind erosion.Vegetation cover cities usually almost entirely represented "cultural plantings" - parks, gardens, lawns, flower beds, walkways. Structure anthropogenic phytocenoses does not match the zonal and regional types of natural vegetation. Therefore, the development of green spaces in cities flows artificial conditions, constantly maintained man. Perennials in the cities develop in conditions of strong oppression.City and weEnvironmental protection - the problem of our age, the problem has become social. Again and again we hear about the danger to the environment, but until now, many of us find them unpleasant but inevitable product of civilization, and believe that we will have time to deal with all the difficulties to identify. But it is not).You should try to use less chemicals, such as cleaning the house, if possible, to go more on the bike, roller skating or walking - it's much more effective and pleasant than standing in long hours of traffic jam, throw trash where it should be, but not anywhere as ... ecology of our city only in our hands.
Thank you for your letter. I'm sorry for not writing to you sooner, I have been busy at school.
In your letter you asked me about summer in my country. Well, I should say it's really hot here, especially in July and August when the temperatures may reach 45 °C. If you decide to come here in summer, make sure to have a broad brimmed hat.
I like summer anyway, because I don't have to go to school. And what is your favourite season? What is summer like in the UK? How do you spend your summer?
Dear John,
Thank you for your letter. I'm sorry for not writing to you sooner, I have been busy at school.
In your letter you asked me about summer in my country. Well, I should say it's really hot here, especially in July and August when the temperatures may reach 45 °C. If you decide to come here in summer, make sure to have a broad brimmed hat.
I like summer anyway, because I don't have to go to school. And what is your favourite season? What is summer like in the UK? How do you spend your summer?
Write back soon.
Best wishes,
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