ENVIRONMENTAL SCIENCE

ENVIRONMENTAL SCIENCE 10th Grade - Biology

WhatWeStudy Contents : How plants and animals are interdependent and interact with each other? Recognise the importance of biogeochemical cycles !! Explain the gaseous and sedimentary bio-geo chemical cycles with schematic diagram Recall the various types and causes for environmental pollution and suggest measures to prevent the same Land, Air, Water & Minerals Land, Air, Water & Minerals

INTERDEPENDENCE OF PLANTS AND ANIMALS Non Living Environment Land, Air, Water & Minerals Living Components (Animals) Land, Air, Water & Minerals

INTERDEPENDANCE Every life activity is influenced by the environmental factors and activities of the living organisms play a important role in maintaining a balance in the environmental factors. Among the living components, plants and animals assume special significance in the ecosystem, mainly because they are linked by the food chain. As a result, there is mutual interaction and interdependence between plants and animals. . Land, Air, Water & Minerals Land, Air, Water & Minerals

INTERDEPENDANCE FROM PLANTS TO ANIMALS • A part of the carbon dioxide required by plants for their photosynthetic activity, is made available by animals. Animals release considerable amount of carbon dioxide into the environment, by way of respiration. • Plants need mineral nutrients for their life processes. They absorb these nutrients directly from the soil. A major source of these nutrients is the decomposition of dead bodies of animals. • The process of excretion by animals forms another major source of addition of nutrients to the soil. • Most of the plants are dependent on animals for processes like pollination and the dispersal of fruits and seeds. • The insectivorous plants like Drosera and Nepenthes obtain their mineral requirement, particularly nitrogen, by directly trapping and digesting insects. Land, Air, Water & Minerals Land, Air, Water & Minerals

INTERDEPENDANCE FROM PLANTS TO ANIMALS Land, Air, Water & Minerals Land, Air, Water & Minerals

INTERDÉPENDANCE FROM ANIMALS TO PLANTS Animals on the other hand, are totally dependent on plants for their food, either directly or indirectly. * Herbivorous animals directly consume plant material from which they obtain all their essential nutrients. * Carnivorous animals obtain their food from the consumption of other animals. Even in these animals, the primary nutrient source will be plants. * Animals require oxygen for carrying on respiration. The major source of this oxygen is the process called photosynthesis seen in green plants. * Plants, particularly trees, provide shelter to a wide variety of animals. Many animals use the trees as their habitat Land, Air, Water & Minerals Land, Air, Water & Minerals

INTERDÉPENDANCE FROM ANIMALS TO PLANTS Land, Air, Water & Minerals Land, Air, Water & Minerals

BIOGEOCHEMICAL AND TYPES OF CYCLES “The Various Chemical Substances moves in the ecosystem in a cyclic manner continuously being exchanged between non –livingand Living components. Such Chemical substances is called as Biogeochemical Cycles” Land, Air, Water & Minerals Carbon Cycle Nitrogen Cycle Phosphorous Cycle Sulphur Cycle Land, Air, Water & Minerals

GASEOUS CYCLES : CARBON CYCLE Carbon is a basic element for all life and is an essential constituent of all organic compounds that compose the protoplasm. Atmospheric carbon dioxide serves as the source of carbon for the synthesis of organic compounds, particularly sugars, in autotrophic land plants. In aquatic ecosystems, carbonates and bicarbonates dissolved in water serve as the source of carbon. Photosynthesis, is thus, responsible for the fixation of carbon into the nutrient pool. Following are the main steps in carbon cycle in nature. The major biological process by which carbon dioxide is fixed from the reservoir pool, is photosynthesis. Green plants are consumed by herbivores and herbivores in turn are consumed by carnivores. Thus, carbon in the form of plant biomass travels as food to the animals in the successive trophic levels. Respiration by plants and animals releases carbon dioxide as a by-product. When these plants and animals die, their dead bodies are decomposed to release carbon dioxide. Some of the dead plants and animals which get buried deep under the earth’s crust, escape oxidation and change into ‘fossil fuels’ like petroleum, through very slow chemical changes. When such fuels are burnt, they release carbon-dioxide. Occasional volcanic eruptions also release gaseous carbon dioxide into the atmosphere. Land, Air, Water & Minerals Land, Air, Water & Minerals

GASEOUS CYCLES : CARBON CYCLE Land, Air, Water & Minerals

GASEOUS CYCLES : NITROGEN CYCLE Nitrogen is one of the essential component of biological molecules such as proteins and nucleic acids with (79%) in the atmosphere. However, this gaseous nitrogen cannot be directly utilized by the organisms in the exchange pool. The process of converting free gaseous nitrogen of the atmosphere into useful forms of compounds of nitrogen, is called nitrogen fixation. It occurs in two ways namely, natural fixation and artificial fixation. Land, Air, Water & Minerals Land, Air, Water & Minerals

GASEOUS CYCLES : NITROGEN CYCLE Land, Air, Water & Minerals Land, Air, Water & Minerals

GASEOUS CYCLES : NITROGEN CYCLE Land, Air, Water & Minerals

GASEOUS CYCLES : OXYGEN CYCLE Atmospheric Oxygen Land, Air, Water & Minerals

ENVIRONMENTAL POLLUTION Definition : Undesirable change in the physical, chemical and biologicalcharacterstics of the environment. . Such changes are caused by substances that are introduced into the environment by humanactivitiescalled as pollutants. Biodegradablepollutants : Biodegradable wastes decompose into soil. Kitchen food scraps Garden waste Paper and egg shells Human and animal waste cardboard boxes Non-degradablepollutants : Non-biodegradable wastes take a long time or never to decompose. Metal cans Bottles Toxic chemicals Plastic products Metal scraps Land, Air, Water & Minerals

Types of Pollution Air Pollution Water Pollution Soil Pollution Noise Pollution We can recognize other forms of pollution such as noise pollution, thermal pollution, radio-active pollution etc Land, Air, Water & Minerals

Air Pollution “An increase in any of the constituents of the atmosphere which is harmful to the living beings and their environment, is known as air pollution” We burn fire wood in our houses and coal in factories, petrol in vehicles. In all these cases carbon dioxide, carbon monoxide and other gases are released into the atmosphere. If these gases reach a concentration which becomes harmful to us or to the environment, then we can consider the air to be polluted Examples : Smog, Acid rain, Indoor Pollution, Dust Particles Know it : Poisonous Gases : CO, CO2 ,Carbonyl chloride, Ammonia, Hydrogen Sulphide and cyanides. NO. SO2 Hydro carbons Watch this you tube Video : Cut copy paste in the IE Browser http://www.youtube.com/watch?v=bTsxx1KZwlM Land, Air, Water & Minerals

Air Pollution Industries, automobiles and modern agricultural operations release a large number of chemicals, smoke, dust and poisonous gases into the atmosphere. Some of the toxic gases undergo photochemical reactions with the oxides of nitrogen in the atmosphere to generate photochemical smog. Smog is a combination of smoke and fog. Smog formation is common in many industrial cities like Mumbai, Kolkatta, Delhi and Bangalore. These gases (SO2 and SO3) when released into atmosphere react with rain water to form acids, which come down as acid rains Land, Air, Water & Minerals

Effects of Air Pollution Land, Air, Water & Minerals

Controls of Air Pollution Air pollution can be controlled by a thorough understanding of its causes. Establishment of industries away from the towns and cities. Increasing the length of the chimneys in industries. Growing more plants and trees Use of efficient engines in automobiles. Use of smokeless choola. Use of petrol without lead (unleaded petrol) Enforcement of regulatory rules of air pollution and rigorous punishment to the defaulters Land, Air, Water & Minerals

Water Pollution “Effluents from various industries, sewage containing domestic wastes and pesticides from agricultural lands are finding their way into water bodies leading to water pollution” Watch this you tube Video : Cut copy paste in the IE Browser http://www.youtube.com/watch?v=ntWSx8BOFfE Land, Air, Water & Minerals

Causes of Water Pollution Industrial wastes : Various kinds of industries like paper mills, sugar factories, iron and steel industries, food processing industries, fertilizer factories, textile mills, electroplating industries and chemical plants release waste waters into the neighbouring water bodies like rivers and lakes. These waste waters often contain toxic materials like cadmium, lead, chromium, mercury, fluorine, acids and alkalies. Sewage water : Sewage contains human and animal excreta in addition to food residues, detergents and other wastes. It is rich in disease causing bacteria and organic substances. Addition of sewage water into natural water bodies seriously affects the quality of water. Rivers like Ganga, Narmada, Kaveri, Godavari, Tungabadhra, Brahmaputra, Krishna and Mahanadi are now known to be highly polluted. Agricultural wastes : These wastes contain residues of fertilizers and pesticides which get very easily carried into the nearly water bodies. Release of superheated water : Release of superheated water from some industries and nuclear power plants results in thermal pollution in natural water bodies. Addition of waste and oil from refineries : Wastes from refineries and oil released into seas and oceans, cause marine pollution which is detrimental to marine life. Land, Air, Water & Minerals

Causes of Water Pollution Industrial pollutants like mercury, chromium, cadmium and lead are poisnous. They are also capable of entering the food chains and cause diseases in man, Mercury is known to cause a disease called Minamata. It causes initial numbness of limbs, lips and tongue. Finally it leads to impairment of motor control, deafness, blurring of vision, cellular degeneration in the brain, spasticity, coma and death. Organochlorinepesticides like D.D.T in the agricultural wastes are non-degradable and move along the food chains. It may lead to biomagnification. Some industrial effluents can cause hangesin the colour, odour and taste of water in the natural water bodies. Contamination of water also leads to spread of water borne diseases such as cholera, amoebiasis and other diseases. Land, Air, Water & Minerals

Control of Water Pollution Sewage treatment : It is done in three steps. In the first step suspended materials are removed. In the second step, the waste water is aerated. This promotes bacterial decomposition of organic compounds. This is followed by chlorination. In the third step, nitrates and phosphates are removed and the water is purified. Effluent Treatment : Industrial effluents are suitably treated to eliminate the pollutants. The steps involve removal of toxic chemicals, neutralization of acids and alkalies, precipitation of metallic compounds and reducing the temperature of waste waters from power plants. Land, Air, Water & Minerals

Soil Pollution Various kinds of domestic wastes, residues of pesticides and fertilizers have been the major sources of soil pollution. There is also the risk of some of these residues entering into food chains in the neighbouring water bodies. Pesticides like B.H.C., D.D.T, etc. contain non-degradable poisonous constituents which enter the human body through food chain. CAUSES OF SOIL POLLUTION 1. Excavation of earth, especially in towns and cities for construction of new buildings 2. Residues from the factories. 3. Indiscriminate use of pesticides. 4. Addition of non degradable domestic wastes like plastic Watch this you tube Video : Cut copy paste in the IE Browser http://www.youtube.com/watch?v=00c4goQRLek http://www.youtube.com/watch?v=_GpI8QBtH8c Land, Air, Water & Minerals

Control of Soil Pollution Minimising the usage of pesticides. Periodic change of crops to increase the soil fertility. Disposal of unwanted garbage created by clinics and hospitals properly either by burning or by burying into the soil. Minimising the usage of plastics. Following the rules and regulations laid down by pollution control board. Land, Air, Water & Minerals

Noise Pollution “Improvement in human civilization has resulted in the use of various kinds of vehicles for transport purposes. Such vehicles have today become a major source of noise pollution” In addition the use of microphones and other audio-equipment in public places have added to the intensity of noise pollution which has a direct effect on human health. EFFECTS OF NOISE POLLUTION It affects human nervous system leading to deafness, headache, blood pressure, brain disorders etc. Harsh noise leads to uneasy feelings, short temper, heart disease, and other related problems. Watch this you tube Video : Cut copy paste in the IE Browser http://www.youtube.com/watch?v=UG5M_CzR1RI http://www.youtube.com/watch?v=-VaaTn_g1_k

Control of Noise Pollution MEASURES TO CHECK THE NOISE POLLUTION : Replacing very old machines by new ones. Providing labourers in industries with ear plugs and improved sound proof instruments. Parking for high sounding vehicles should be only outside the city limits. Regulation of loud speakers used in functions. Growing broad-leafed plants which can absorb sound Land, Air, Water & Minerals

ENVIRONMENTAL SCIENCE