NATURAL RESOURCES

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NATURAL RESOURCES:

NATURAL RESOURCES name-: aniket Sanjay Ghodinde roll no -: 906 Std -: ix subject-: science

Introduction To Natural Resources:

Introduction To Natural Resources The resources we get from nature are called as natural resources. These are equally important for the survival of human beings. There are two main natural resources :- ( i ) Water (ii) Air (iii) Others are :- Plants Coal, fossil fuels, rock and mineral resources Forestry Soils Water, oceans, lakes, groundwater and rivers

Air:

A ir Air is nothing but it is just the part of Earth's atmosphere that We humans breathe Air ,  mixture of gases comprising the Earth’s atmosphere. The mixture contains a group of gases of nearly constant concentrations and a group with concentrations that are variable in both space and time. The atmospheric gases of steady concentration (and their proportions in percentage by volume ) Although present in relatively small amounts, these variable constituents may be very important for maintaining life on Earth’s surface. Water vapour is the source for all forms of precipitation and is an important absorber and emitter of infrared radiation. Carbon dioxide, besides being involved in the process of photosynthesis, is also an important absorber and emitter of infrared radiation. Ozone, which is present mainly in the atmospheric region 10 to 50 km (6 to 30 miles) above the Earth’s surface, is an effective absorber of ultraviolet radiation from the Sun and effectively shields the Earth from all radiation of wavelengths less than 3,000 angstroms.

Water:

Water Water is a chemical substance with the chemical formula  H2O.Its molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at  ambient conditions , but it often co-exists on Earth with its solid  state, Ice , and gaseous state, water vapor or steam . Water covers 71% of the Earth's surface , is vital for all known forms of life and there are various theories about the origin of water on Earth On Earth, 96.5% of the planet's water is found in seas and oceans, 1.7% in groundwater, 1.7% in glaciers and the ice caps of Antarctica and Greenland, a small fraction in other large water bodies, and 0.001% in the air as vapour, clouds (formed of solid and liquid water particles suspended in air), and precipitation. Only 2.5% of the Earth's water is freshwater, and 98.8% of that water is in ice and groundwater. Less than 0.3% of all freshwater is in rivers, lakes, and the atmosphere, and an even smaller amount of the Earth's freshwater (0.003%) is contained within biological bodies and manufactured products .

Plants:

Plants Plants are living organisms belonging to the kingdom Plantae . The scientific study of plants, known as botany , has identified about 350,000 extant Species of plants, defined as seed plants, bryophytes, ferns and fern allies. As of 2004, some 287,655 species had been identified, of which 258,650 are flowering and 18,000 bryophytes. Green plants obtain most of their energy from sunlight by a process called photosynthesis. Humans are dependent upon plants. Directly or indirectly, plants provide food, clothing, fuel, shelter, and many other necessities of life. Humankind's dependence on crops such as wheat and corn (maize) is obvious, but without grass and grain the livestock that provide people with food and other animal products could not survive either.

Soil:

Soil Soil is the mixture of minerals, organic matter, gases, liquids and a myriad of micro- and macro- organisms that can support plant life. It is a natural body that exists as part of the pedosphere and it performs four important functions: as a medium for plant growth and of water storage, supply and purification; as a modifier of the atmosphere; and finally as a habitat for organisms that take part in decomposition and creation of a habitat for other organisms . One of the most important natural resources is soil. Like air and water, soil is necessary to life on Earth. Without it, plants could not grow and plant-eating animals could not live; meat-eating animals would also perish. Civilizations depend on the quality of their soil to grow their food and to serve as a living filter that purifies the wastes they produce . Soil is considered the "skin of the earth" with interfaces between the lithosphere, hydrosphere, atmosphere, and biosphere . Soil consists of a solid phase (minerals & organic matter) as well as a porous phase that holds gases and water. Accordingly , soils are often treated as a three-state system .

Fossil Fuels:

Fossil Fuels Fossil fuels are fuels formed by natural processes such as anaerobic decomposition of buried dead organisms. The age of the organisms and their resulting fossil fuels is typically millions of years, and sometimes exceeds 650 million years . Fossil fuels contain high percentages of carbon and include coal, petroleum, and natural gas All the machines of modern life require energy to make them run. About 90 percent of that energy comes from burning fossil fuels. Fossil fuels include petroleum (oil), coal, and natural gas. These materials are called fossil fuels because, like fossils, they are the remains of organisms that lived ... Coal is an important type of fossil fuel. It is buried underground and must be dug up.

Mineral:

Mineral A mineral is a naturally occurring substance that is solid and stable at room temperature, representable by a chemical formula, usually abiogenic , and has an ordered atomic structure. It is different from a rock, which can be an aggregate of minerals or non-minerals and does not have a specific chemical composition Minerals can be described by various physical properties which relate to their chemical structure and composition. Common distinguishing characteristics include crystal structure and habit, hardness, lustre, diaphaneity, colour, streak, tenacity, cleavage, fracture, parting, and specific gravity. More specific tests for minerals include reaction to acid, magnetism, taste or smell, and radioactivity . There are several thousand known mineral species, about 100 of which constitute the major mineral components of rocks; these are the so-called rock-forming minerals.

Air Pollution:

Air Pollution Air pollution is the introduction of chemicals, particulate matter, or biological materials that cause harm Or discomfort to humans or other living organisms, or damages the natural environment into the atmosphere. The atmosphere is a complex dynamic natural gaseous system that is essential to support life on planet Earth. Stratospheric ozone depletion due to air pollution has long been recognized as a threat to human health as well as to the Earth's ecosystems . Indoor air pollution and urban air quality are listed as two of the world's worst pollution problems in the 2008 Blacksmith Institute World's Worst Polluted Places report .

Water Pollution:

Water Pollution Water pollution is the contamination of water bodies (e.g. lakes, rivers, oceans, aquifers and groundwater). Water pollution occurs when pollutants are directly or indirectly discharged into water bodies without adequate treatment to remove harmful compounds . Water pollution affects plants and organisms living in these bodies of water. In almost all cases the effect is damaging not only to individual species and populations, but also to the natural biological communities . Water pollution is a major global problem which requires ongoing evaluation and revision of water resource policy at all levels (international down to individual aquifers and wells). It has been suggested that it is the leading worldwide cause of deaths and diseases , and that it accounts for the deaths of more than 14,000 people daily . An estimated of 580 people in India die of water pollution related illness every day . Some 90% of China's cities suffer from some degree of water pollution , and nearly 500 million people lack access to safe drinking water. In addition to the acute problems of water pollution in developing countries, developed countries continue to struggle with pollution problems as well. In the most recent national report on water quality in the United States, 45 percent of assessed stream miles, 47 percent of assessed lake acres, and 32 percent of assessed bays and estuarine square miles were classified as polluted .

Water Cycle:

Water Cycle The water cycle, also known as the hydrologic cycle or H 2 O cycle, describes the continuous movement of water on, above and below the surface of the Earth. Water can change states among liquid, vapour , and ice at various places in the water cycle. Although the balance of water on Earth remains fairly constant over time, individual water molecules can come and go. The water moves from one reservoir to another, such as from river to ocean, or from the ocean to the atmosphere, by the physical processes of evaporation, condensation, precipitation, infiltration, runoff, and subsurface flow. In so doing, the water goes through different phases: liquid, solid , and gas.

Nitrogen Cycle:

Nitrogen Cycle The nitrogen cycle is the process by which nitrogen is converted between its various chemical forms. This transformation can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification . The majority of Earth's atmosphere (78%) is nitrogen , making it the largest pool of nitrogen. However, atmospheric nitrogen has limited availability for biological use, leading to a scarcity of usable nitrogen in many types of ecosystems. The nitrogen cycle is of particular interest to ecologists because nitrogen availability can affect the rate of key ecosystem processes, including primary production and decomposition. Human activities such as fossil fuel combustion, use of artificial nitrogen fertilizers, and release of nitrogen in wastewater have dramatically altered the global nitrogen cycle

Carbon Cycle:

Carbon Cycle The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere , geosphere, hydrosphere, and atmosphere of the Earth. Along with the nitrogen cycle and the water cycle, the carbon cycle comprises a sequence of events that are key to making the Earth capable of sustaining life; it describes the movement of carbon as it is recycled and reused throughout the biosphere. Carbon is continuously cycled between the oceans , land, and the atmosphere . The atmospheric carbon is primarily carbon dioxide. Carbon, on and , occurs primarily in living biota and decaying organic matter. Dissolved carbon dioxide and small organisms like plankton that store carbon dioxide are major sources in the ocean. Carbon is measured in Gigatons , with the deep ocean containing almost 40,000 Gt , compared to about 2,000 Gt on land and 750 Gt in the atmosphere.

Oxygen Cycle:

Oxygen Cycle oxygen cycle,   circulation of oxygen in various forms through nature. Free in the air and dissolved in water, oxygen is second only to nitrogen in abundance among uncombined elements in the atmosphere. Plants and animals use oxygen to respire and return it to the air and water as carbon dioxide (CO 2 ). CO 2 is then taken up by algae and terrestrial green plants and converted into carbohydrates during the process of photosynthesis, oxygen being a by-product. The waters of the world are the main oxygen generators of the biosphere; their algae are estimated to replace about 90 percent of all oxygen used. Oxygen is involved to some degree in all the other biogeochemical cycles. For example, over time, detritus from living organisms transfers oxygen-containing compounds such as calcium carbonates into the lithosphere.

Greenhouse Effect:

Greenhouse Effect The greenhouse effect is a process by which thermal radiation from a planetary surface is absorbed by atmospheric greenhouse gases, and is re-radiated in all directions. Since part of this re-radiation is back towards the surface and the lower atmosphere, it results in an elevation of the average surface temperature above what it would be in the absence of the gases . Earth’s natural greenhouse effect makes life as we know it possible. However, human activities, primarily the burning of fossil fuels and clearing of forests, have intensified the natural greenhouse effect, causing global warming .

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