Environmental Problems . The man has been able to modify the environment with their activities. Thanks to their peculiar mental and physical abilities, they managed to escape the environmental constraints that limited other species and alter the environment to suit their needs. These activities have irreparably damaged the environment and produced a myriad of environmental problems that affect and endanger the survival of species.
Summary
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- 1 Environment
- 2 Constituents of the environment
- 3 Environmental problems
- 1 Carbon dioxide
- 2 Acidification
- 3 Destruction of ozone
- 4 Chlorinated hydrocarbons
- 5 Other toxic substances
- 6 Radiation
- 7 Loss of virgin lands
- 8 Soil erosion
- 9 Demand for water and air
- 4 Earth Summit
- 5 Perspectives
- 6 See also
- 7 Sources
Environment
Environment
It is defined as a set of abiotic elements ( solar energy , soil , water and air ) and biotic (living organisms) that make up the thin layer of the Earth called the biosphere , sustenance and home of living beings . It is therefore everything that affects a living being and especially conditions the life circumstances of the people or society in their life.
It includes the set of natural, social and cultural values existing in a given place and time, which influence human life and future generations. In other words, it is not only about the space in which life develops but also includes living beings, objects, water, soil, air and the relationships between them, as well as elements as intangible as culture .
Environmental constituents
Protect the environment!
The atmosphere , which protects the Earth from excess ultraviolet radiation and allows life to exist, is a gaseous mixture of nitrogen , oxygen , hydrogen , carbon dioxide, water vapor, other elements and compounds, and dust particles. Heated by the Sun and the radiant energy of the Earth, the atmosphere circulates around the planet and modifies the thermal differences. As regards water , 97% is found in the oceans, 2% is ice and the remaining 1% is fresh water from rivers, lakes, groundwater, and atmospheric and soil moisture .
Soil is the thin blanket of matter that sustains life on earth. It is the product of the interaction of the climate and the rocky substrate or bedrock, such as glacial moraines and sedimentary rocks, and vegetation. Living organisms, including humans, depend on all of them. Plants use water, carbon dioxide, and sunlight to convert raw materials into carbohydrates through photosynthesis; animal life, in turn, depends on plants in a sequence of interconnected links known as a food web.
During its long history, the Earth has slowly changed. Continental drift (the result of plate tectonics) separated continental masses, oceans invaded and retreated from land, and mountains rose and eroded, depositing sediment along coasts Climates warmed and cooled, and life forms appeared and disappeared as the environment changed.
The most recent major environmental event in Earth’s history occurred in the Quaternary, during the Pleistocene (between 1.64 million and 10,000 years ago), also called the Ice Age. The subtropical climate disappeared and changed the face of the northern hemisphere. Large ice sheets advanced and retreated four times in North America and three times in Europe , oscillating the climate from cold to temperate, influencing plant and animal life, and ultimately giving rise to the climate we know today. Hence, this era receives, interchangeably, the names of recent, postglacial and Holocene. During this time the planet’s environment has remained more or less stable.
Environmental problems
The human being, appeared late in the history of the Earth, but has been able to modify the environment with their activities. Thanks to their peculiar mental and physical abilities, they managed to escape the environmental constraints that limited other species and alter the environment to suit their needs.
The first humans undoubtedly lived more or less in harmony with the environment, like other animals, their distance from the wild began in prehistory, with the first agricultural revolution. The ability to control and use fire allowed them to modify or eliminate natural vegetation, and the domestication and grazing of herbivorous animals led to overgrazing and soil erosion. The cultivation of plants also caused the destruction of natural vegetation to make room for crops and the demand for firewood led to the denudation of mountains and the depletion of entire forests. Wild animals were hunted for their meat and destroyed if they were considered pests or predators.
While human populations remained small and their technology modest, their impact on the environment was only local. However, as the population grew and technology improved and increased, more significant and widespread problems emerged. The rapid technological advance produced after the Middle Ages culminated in the Industrial Revolution, which brought with it the discovery, use and exploitation of fossil fuels, as well as the intensive exploitation of the Earth’s mineral resources.
It was with the Industrial Revolution that human beings really began to change the face of the planet, the nature of its atmosphere, and the quality of its water. Today, the unprecedented demands placed on the environment by rapid human population growth and technological development is producing an increasingly rapid decline in its quality and in its ability to sustain life.
Carbon dioxide
Greenhouse effect
Greenhouse effect
One of the impacts that the use of fossil fuels has produced on the terrestrial environment has been the increase in the concentration of carbon dioxide (CO2) in the atmosphere. The amount of atmospheric CO2 since 1750 has increased by about 30%. What is significant about this change is that it can cause an increase in the Earth’s temperature through a process known as the greenhouse effect. The carbon dioxide atmosphere tends to prevent the escape longwave radiation to outer space; Since more heat is produced and less can escape, the Earth’s global temperature rises.
A global warming significantly in the atmosphere would have serious effects on the environment. It would accelerate the melting of the polar ice caps, raise sea levels, change the climate regionally and globally, alter natural vegetation and affect crops. These changes, in turn, would have a huge impact on human civilization.
Acidification
Acid rain
Effects of acid rain
The acidification is also due to the use of fossil fuels and the emission of sulfur dioxide and nitrogen oxides from power plants and exhaust from motor vehicles. These products interact with sunlight, humidity and oxidants producing sulfuric and nitric acid, which are transported by atmospheric circulation and fall to the ground, carried away by rain and snow in the so-called acid rain , or in the form of deposits. dry, particles and atmospheric gases.
Acid rain is a major global problem. The acidity of some precipitation in the northern United States and Europe is equivalent to that of vinegar. Acid rain corrodes metals, wears away stone buildings and monuments, damages and kills vegetation, and acidifies lakes, streams, and soils, especially in parts of the northeastern United States and northern Europe. In these regions, lake acidification has killed fish populations. Today it is also a problem in the southeastern United States and central North Africa. Acid rain can also retard the growth of forests; it is associated with their decline at high altitudes in both the United States and Europe.
Ozone destruction
Hole in the Ozone Layer (Cartoon)
Satellite view of the hole in the Ozone Layer
Decades ago scientists began to discover that human activity was having a negative impact on the ozone layer, a region of the atmosphere that protects the planet from harmful ultraviolet rays. If that gaseous layer did not exist, which is about 40 km above sea level, life would be impossible on our planet. Studies showed that the ozone layer was being affected by the increasing use of chlorofluorocarbons (CFCs, fluorine compounds), which are used in refrigeration, air conditioning, cleaning solvents, packaging materials and aerosols.
Destruction of the Ozone Layer (Cartoon)
The chlorine , a chemical secondary CFCs attacks ozone, which consists of three oxygen atoms, one snatching to form chlorine monoxide. It then reacts with oxygen atoms to form oxygen molecules, releasing chlorine molecules that break down more ozone molecules.
The thinning of the ozone layer exposes terrestrial life to an excess of ultraviolet radiation, which can cause skin cancer and cataracts, reduce the response of the immune system, interfere with the photosynthesis process of plants and affect the growth of phytoplankton oceanic. Due to the growing threat posed by these dangerous effects on the environment, many countries are trying to join forces to reduce greenhouse gas emissions. However, CFCs can remain in the atmosphere for more than 100 years, so ozone destruction will continue for decades.
Chlorinated hydrocarbons
The extensive use of synthetic pesticides derived from chlorinated hydrocarbons in pest control has had disastrous side effects for the environment. These organochlorine pesticides are very persistent and resistant to biological degradation. Very poorly soluble in water, they adhere to plant tissues and accumulate in soils, the substrate at the bottom of streams and ponds, and the atmosphere. Once volatilized, pesticides are distributed throughout the world, contaminating wild areas far away from agricultural regions, and even in the Arctic and Antarctic areas.
Although these synthetic chemicals do not exist in nature, they do penetrate the food chain. Pesticides are ingested by herbivores or penetrate directly through the skin of aquatic organisms such as fish and various invertebrates. The pesticide becomes even more concentrated when going from herbivores to carnivores. It reaches high concentrations in the tissues of animals that occupy the highest links in the food chain, such as the peregrine falcon, the eagle and the bearded vulture.
There is another group of compounds closely linked to DDT: polychlorinated biphenyls (PCBs). They have been used for years in industrial production, eventually penetrating the environment. Its impact on humans and wildlife has been similar to that of pesticides. Due to its extreme toxicity, the use of PCBs has been restricted to the insulators of electrical transformers and capacitors.
TCDD is the most toxic of another related group of highly toxic compounds, the dioxins or dibenzo-para-dioxins. The degree of toxicity to humans of these carcinogens has not yet been established. TCDD can be found as an impurity in wood and paper preservatives and herbicides. The Agent Orange , a defoliant widely used, contains traces of dioxin.
Other toxic substances
Toxic substances are chemical products whose manufacture, processing, distribution, use and disposal represent an unacceptable risk to human health and the environment. Most of these toxic substances are synthetic chemicals that enter the environment and persist for long periods of time. Significant concentrations of toxic substances occur in chemical dumps. If they seep into soil or water, they can contaminate water supplies, air, crops, and domestic animals, and have been associated with human birth defects, abortions, and organic diseases. Despite known risks, the problem is not on track.
Recently, more than 4 million new synthetic chemicals have been manufactured in a fifteen-year period, and 500 to 1,000 more new products are created each year.
Radiation
Negative effects of radiation
Although atmospheric nuclear testing has been banned by most countries, eliminating a major source of radioactive fallout, nuclear radiation remains an environmental problem. Power plants always release small amounts of nuclear waste into water and the atmosphere, but the main danger is the possibility of nuclear accidents, which release huge amounts of radiation into the environment, as happened in Chernobyl , Ukraine , in 1986 .
A more serious problem facing the nuclear industry is the storage of nuclear waste, which remains toxic for 700 to 1 million years. The security of a storage during geological periods of time is, to say the least, problematic; Meanwhile, radioactive waste accumulates, threatening the integrity of the environment.
Loss of virgin lands
Deforestation of soils by indiscriminate logging
Increasing numbers of human beings are beginning to enclose the remaining virgin lands, even in areas considered more or less safe from exploitation. The insatiable demand for energy has imposed the need to exploit the gas and oil of the Arctic regions, jeopardizing the delicate ecological balance of the tundra ecosystems and their wildlife. Rainforests and tropical forests, especially in Southeast Asia and the Amazon, are being destroyed at an alarming rate to obtain wood, clear land for pastures and crops, for pine plantations and for human settlements.
In the 1980s it was estimated that forest stands were being destroyed at a rate of 20 ha per minute. Another estimate gave a destruction rate of more than 200,000 km2 per year. In 1993, the data obtained via satellite made it possible to determine a rate of destruction of almost 15,000 km2 per year, only in the Amazon basin. This tropical deforestation could lead to the extinction of up to 750,000 species, which would represent the loss of a whole multiplicity of products: food, fibers, drugs, dyes, gums and resins. Furthermore, the expansion of farmland and grazing land for domestic livestock in Africa, as well as the illegal trade in endangered species and animal products, could spell the end of large African mammals.
Soil erosion
Soil erosion
Soil erosion is accelerating on all continents and is degrading some 2 billion hectares of cropland and grazing land, posing a serious threat to the global food supply. Every year, soil erosion and other forms of land degradation cause a loss of between 5 and 7 million hectares of arable land.
Soils eroded by droughts
In the Third World , the growing need for food and firewood has resulted in the deforestation and cultivation of steep slopes, which has produced severe erosion of the slopes. To further complicate the problem, one must take into account the loss of prime farmland due to industry, swamps, the expansion of cities and roads. Soil erosion and the loss of farmland and forests further reduce the moisture-holding capacity of soils and add sediment to streams, lakes and reservoirs. See also Soil degradation.
Demand for water and air
The erosion problems described above are compounding the growing global water supply problem. Most of the problems in this field occur in the semi-arid and coastal regions of the world. Expanding human populations require irrigation and water systems for industry; This is depleting underground aquifers to such an extent that salt water is beginning to penetrate them along coastal areas in the United States, Israel, Syria, the Arab states of the Persian Gulf, and some areas of the countries bordering the Mediterranean Sea ( Spain, Italy and Greece mainly).
Some of the world’s largest cities are depleting their water supplies and metropolises like New Delhi or Mexico City are pumping water from increasingly remote locations. In inland areas, porous rocks and sediments compact as they lose water, causing problems due to the progressive subsidence of the surface; this phenomenon is already a serious problem in Texas, Florida and California.
The world is also experiencing a progressive decline in the quality and availability of water. In 2000, 508 million people lived in 31 countries affected by water scarcity and, according to estimates by the World Health Organization (WHO), approximately 1.1 billion people lacked access to clean water. In many regions, water supplies are contaminated with toxic chemicals and nitrates. Waterborne diseases affect a third of humanity and kill 10 million people a year.
Earth Summit
In your hands is the care and conservation of the Environment
In June 1992 , the United Nations Conference on Environment and Development , also known as the Earth Summit , met for 12 days in the vicinity of Rio de Janeiro , Brazil . This summit developed and legitimized an agenda of measures related to environmental, economic and political change. The purpose of the conference was to determine what environmental reforms needed to be undertaken in the long term, and to initiate processes for their implementation and international monitoring. Conventions were held to discuss and approve documents on the environment.
June 5 World Environment Day
The main issues addressed in these conventions included climate change , biodiversity , forest protection , Agenda 21 (a 900-page environmental development project), and the Rio Declaration (a six-page document calling for environmental integration and economic development). The Earth Summit was a historical event of great significance. Not only did it make the environment a global priority, it was attended by delegates from 178 countries, making it the largest conference ever held.
Perspectives
The future prospects, as far as the environment is concerned, are unclear. Despite economic and political changes, interest and concern for the environment is still important. Air quality has improved, but the problems of acid rain, chlorofluorocarbons, ozone loss and the enormous air pollution of eastern Europe are pending and require coordinated action. As long as acid rain does not abate , loss of life will continue in northern lakes and streams, and forest growth may be affected.
Water pollution will continue to be a problem as long as population growth continues to put pressure on the environment. The infiltration of toxic waste into underground aquifers and the intrusion of salt water into coastal freshwater aquifers has not been interrupted. The depletion of aquifers in many parts of the world and the increasing demand for water will produce conflicts between agricultural, industrial and domestic use of it. The scarcity will impose restrictions on the use of water and will increase the cost of its consumption. Water could become the energy crisis of the early 21st century. Pollution of fresh and coastal waters, along with overexploitation,
If coordinated efforts are not made to save habitats and reduce poaching and illegal international trafficking in wildlife, many of them will go extinct. Despite our knowledge of how to reduce soil erosion, it continues to be a global problem. This is largely due to the fact that many agronomists and urban planners show little interest in controlling it. Finally, the destruction of virgin lands, both in temperate and tropical regions, can lead to a massive extinction of plant and animal life forms.
To reduce environmental degradation, societies must recognize that the environment is finite. Specialists believe that, as populations and their demands grow, the idea of continued growth should make way for a more rational use of the environment, but that this can only be achieved with a spectacular change in attitude on the part of the human species. The impact of the human species on the environment has been compared to the great catastrophes of the Earth’s geological past; Regardless of society’s attitude towards continued growth, humanity must recognize that attacking the environment endangers the survival of its own species.
In efforts to control environmental deterioration, in March of 2002 , it was put into orbit the European environmental satellite Envisat , in order to obtain accurate information on the environment. Envisat has 10 scientific instruments that will collect data on the level of the oceans, greenhouse gas emissions, floods, the size of the ozone layer, or deforestation, among others. The data sent by the satellite will serve, not only to know the state of ecosystems, but also to make political decisions and control compliance, by different countries, of the Kyoto Protocol and other environmental treaties.
