Sound is measured in decibels (dB). An increase of about 10 dB is approximately double the increase in loudness.

A person’s hearing can be damaged if exposed to noise levels over 75 dB over a prolonged period of time.

The World Health Organization recommends that the sound level indoors should be less than 30 dB.

Ambient Noise Level Monitoring –   Noise Pollution (Control and Regulation) Rules, 2000 define ambient noise levels for various areas as follows-

1. Industrial Area—75DB to 70Db (Day time-6am to 10pm and night time 10pm to 6am ..75 is day time and 70 is night time)
2. Commercial Area–65 to 55
3. Residential Area–55 to 45
4. Silence Zone– 50  to 40

• The Government of India on Mar 2011 launched a Real time Ambient Noise Monitoring Network.
• Under this network, in phase- I, five Remote Noise Monitoring Terminals each have been installed in different noise zones in seven metros (Delhi, Hyderabad, Kolkata, Mumbai, Bangalore, Chennai and Lucknow).

In Phase II another 35 monitoring stations will be installed in the same seven cities.

Phase III will cover installing 90 stations in 18 other cities.

Phase-III cities are Kanpur, Pune, Surat, Ahmedabad,  Nagpur, Jaipur,  Indore,

Bhopal, Ludhiana, Guwahati, Dehradun, Thiruvananthpuram, Bhubaneswar,

Patna, Gandhinagar, Ranchi, Amritsar and Raipur.

Silence Zone is an area comprising not less than 100 metres around hospitals, educational institutions, courts, religious places or any other t area declared as such by a competent authority.

The rapid growth of technology, upgradation of technical innovations and a high rate of obsolescence in the electronics industry have led to one of the fastest growing waste streams in the world which consist of end of life electrical and electronic equipment products. It comprises a whole range of electrical and electronic items such as refrigerators, washing machines, computers and printers, televisions, mobiles, i-pods, etc., many of which contain toxic materials. Many of the trends in consumption and production processes are unsustainable and pose serious challenge to environment and human health.

E-waste is not hazardous if it is stocked in safe storage or recycled by scientific methods or transported from one place to the other in parts or in totality in the formal sector. The e-waste can be considered hazardous if recycled by primitive methods

Major Toxins in E‐waste

• Toxins in e‐waste include polyvinyl chloride (PVC plastics), copper, lead, mercury, arsenic (in  older models), cadmium, manganese, cobalt,  gold, and iron.
• Between 1994 and 2003, disposal of PCs resulted in 718,000 tons of lead, 287 tons of  mercury, and 1,363 tons of cadmium
• Mercury, chromium, lead, and  brominated flame retardants are likely to cause the most adverse health effects in humans.

Survey was carried out by the Central Pollution Control Board (CPCB) during 2005

In India, among top ten cities; Mumbai ranks first in generating e-waste followed by Delhi, Bangalore, Chennai, Kolkata, Ahmadabad, Hyderabad, Pune, Surat and Nagpur.

E — WASTE

E-waste is not hazardous if it is stocked in safe storage or recycled by scientific methods or transported from one place to the other in parts or in totality in the formal sector. The e-waste can be considered hazardous if recycled by primitive methods

Survey was carried out by the Central Pollution Control Board (CPCB) during 2005

In India, among top ten cities; Mumbai ranks first in generating e-waste followed by Delhi, Bangalore, Chennai, Kolkata, Ahmadabad, Hyderabad, Pune, Surat and Nagpur.

 

SOLID WASTE

the discarded (abandoned or considered waste-like) materials

does not include solid or dissolved materials in domestic sewage, or

solid or dissolved materials in irrigation return flows or industrial discharges0

Conventional plastics have been associated with reproductive problems in both humans and wildlife.

Dioxin (highly carcinogenic and toxic) by-product of the manufacturing process is one of the chemicals believed to be passed on through breast milk to the nursing infant.

Burning of plastics, especially PVC releases this dioxin and also furan into the  atmosphere.

Pyrolysis-It is a process of combustion in absence of oxygen or the material burnt under controlled atmosphere of oxygen. It is an alternative to incineration. The gas and liquid thus obtained can be used as fuels.

 

Waste Minimization Circles (WMC)

helps Small and Medium Industrial Clusters in waste minimization in their industrial plants.  assisted by the World Bank with the Ministry of Environment and Forests acting   as the nodal ministry.  being implemented with the assistance of National   Productivity Council (NPC), New Delhi.

aims to realise the objectives of the Policy Statement for Abatement of Pollution (1992), which states that the government should educate citizens about environmental risks, the economic and health dangers of resource degradation and the real economic cost of natural resources.

BIOREMEDIATION

the use of microorganisms (bacteria and fungi) to degrade the environmental contaminants into less toxic forms.

Phytoremediation

is use of plants to remove contaminants from soil and water .

Rhizofiltration

• a water remediation technique that involves the uptake of contaminants by plant roots.
• used to reduce contamination in natural wetlands and estuary areas.

 

ENVIRONMENTAL IMPACT ASSESSMENT

Notification on Environmental Impact Assessment (EIA) of developmental

projects 1994 under the provisions of Environment (Protection) Act, 1986 making EIA  mandatory for 29 categories of developmental projects. One more item was added to the list in January, 2000. environmental impact assessment statutory for 30 activities

Environment Impact Assessment Notification of 2006 has categorized the developmental projects  in two categories, i.e., Category A and Category B

Ministry of Environment & Forests

‘Category A’ projects are appraised at national level by expert appraisal committee

India has constituted the State Level Environment Impact Assessment Authority (SEIAA) and State Level Expert Appraisal Committee (SEAC)  to decentralize the environmental clearance process

The objective of EIA is to foresee and address potential environmental problems/  concerns at an early stage of project planning and design.

 

 

The EIA notification establishes four stages for obtaining Environmental Clearance.

1. Screening
2. Scoping and consideration of alternatives Baseline data collection
3. Impact prediction
4. Assessment of alternatives, delineation of mitigation measures and environmental impact statement
5. Public hearing
6. Environment Management Plan Decision making
7. Monitoring the clearance conditions

Screening- It is only for Categories B

Screening Criteria are based upon:

• Scales of investment; •       Type of development; and, •      Location of development

B1 Categories project require Environmental Impact Assessment while B2 category projects are exempted from EIA.

State Level Expert Appraisal Committee determine about project categories

Climate Change

 

• It is the long term change in the statistical distribution of weather patterns over periods of time
• Though it has been happening naturally for millions of years, in recent years it has accelerated due to anthropogenic causes and has been causing global warming.
• UNFCCC defines climate change as – “a change of climate which is attributed directly or indirectly to human activitythat alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods”

 

Climate Change Mitigation

• Alternative Energy sources
  • Renewable energy
  • Nuclear Power
  • Reduce the carbon intensity of fossil fuels
• Energy efficiency and conservation
  • Transport and urban planning
  • Building design
  • Reforestation and avoid deforestation
  • Eliminating waste methane
• Geoengineering
  • Greenhouse gas remediation
    • Biomass
    • Carbon air capture
    • Carbon capture and storage
  • Societal control
    • Population
    • Sustainable life-style

 

Soil Pollution is the Contamination of the soil by human and natural activities which may cause harmful effects on living beings.
This may be due to the following factors.

(i) Industrial wastes: Industries are the major causes for soil pollution Textiles, steel, paper, Cement, oil, dyeing and other industries are responsible for soil pollution. Toxic organic compounds and phenol destroy the fertility of the soil.
(ii) Biological agents – Fungi, protozoa, bacteria are important Biological agents for soil pollution. The human and animal wastes, garbage, waste water generates heavy soil pollution.
(iii) Radio active pollutants: Atomic reactor, nuclear radio active devices releases radio active pollutants. These pollutants enter the land and accumulate there by causing soil pollution.
(iv) Pesticides: Pesticides pollute the soil. There are of two types (i) chlorinated hydrocarbon insecticide (2) Organic phosphorous pesticides. Common chlorinated hydrocarbon insecticides are DDT, BHC.

Organo phosphorous insecticides are synthetic chemicals like Malathion and parathion.

DDT reduces the activity of sex hormones of male and female. The land with fungicides insecticides causes diseases to human beings.

Fertilizers: These discharge N, Na, K, S, Nitrates etc., into the soil. The nitrate causes cancer.

Polymer, Plastics & other water: These materials appear as garbage. Solid wastes and their quantities increase day by day. They pollute the atmospheres, land and also water badly.

Agricultural practices: Modern agriculture practices pollute the soil to a large extent. Today huge quantities of fertilizers, pesticides, weedicides are added to increase the crop field. Apart from these farm wastes, manure debris, soil erosion containing inorganic chemicals are causing soil pollution.
Effect of soil pollution
1.Organic wastes enter the soil pores and decompose. Pathogenic bacteria spread infection.
2.Compounds containing As, Hg, Cr, Ni, Zn and Fe are toxic to life.
3.Fluorides affect plant development
4.Water logging and salinity increase the dissolved salt content in the soil. Some plants are very sensitive to soil PH and salinity.
Thus land becomes unfit for irrigation.
Control of soil pollution
1.Treat the sewage before land disposal
2.Rotate the crop pattern to allow the soil replenish the nutrients.
3.Preserve and protect top fertile soil, control soil erosion by tree plantation.
4.Fertilizers may be applied only after estimating the soil and crop measures.
5.Production of natural fertilizers Excessive use of chemical fertilizers and insecticides should be avoided. Bio pesticides should be used instead of toxic chemical pesticides.
6.Proper hygienic condition- People should be trained regarding the sanitary habits.
7.Recycling and reuse of waster – The wastes such as paper, plastic, metals, glasses should be recycled and used.

 

Fresh water ecosystems- The salt content of fresh bodies is very low, always less than 5 ppt  (parts per thousand). E.g lakes, ponds, pools, springs, streams, and rivers

Marine ecosystems – the water bodies containing salt concentration equal to or above that of sea water (i.e., 35 ppt or above). E.g shallow seas and open ocean   Brackish water ecosystems- these water bodies have salt content in between 5 to 35 ppt. e.g. estuaries, salt marshes, mangrove swamps and forests.

 

AQUATIC ORGANISMS

The aquatic organisms are classified on the basis Of their one of occurrence and their ability to cross these zones. can be classified on the basis of their life form or location into five groups

1. Neuston:

These are unattached organisms which live at the air-water interface such as floating plants, etc.

Some organisms spend most of their lives on top of the air-water interface such as water striders, while others spend most of their time just beneath the air-water interface and obtain most of their food within the water.

E.g., beetles and back-swimmers.

2. Periphyton:

These are organisms which remain attached to stems and leaves of rooted plants or substances emerging above the bottom mud such as sessile algae and their associated group of animals.

3. Plankton

This group includes both microscopic plants like algae (phytoplankton) and

animals like crustaceans and protozoans (zooplankton) found in all aquatic

ecosysteins, except certain swift moving waters

The locomotory power of the planktons is limited so that their distribution is

controlled, largely, by currents in the aquatic ecosystems.

4. Nekton:

This group contains animals which are  swimmers.

The nektons are relatively large and powerful as they have to overcome the water currents.

5. Benthos:

The benthic organisms are those found living in the bottom of the water mass.

Practically every aquatic ecosystem contains well developed benthos

Factors Limiting the Productivity of Aquatic Habitats

1. Sunlight :

Sunlight penetration rapidly diminishes as it passes down the column of water.

The depth to which light penetrates a lake determines the extent of plant distribution.

Based on light penetration and plant distribution they are classified as photic and aphotic zones

Photic zone:

It is the upper layer of the aquatic ecosystems, up to which light penetrates and within which photosynthetic activity is confined.

The depth of this zone depends on the transparency of water.

photic (or .”euphotic”) zone is the lighted and usually well-mixed portion that extends from the lake surface down to where the light level is 1% of that at the surface.

Aphotic zone:

The lower layers of the aquatic ecosystems, where light penetration and plant growth are restricted forms the aphotic zone.

Only respiration activity takes place.(photic-both respiration and photosynthesis take place )

Aphotic zone is positioned below the littoral and photic zones to bottom of the lake where light levels are too low for photosynthesis.

This deep, unlit region is also known as the profundal zone.

Dissolved oxygen:

Oxygen enters the aquatic ecosystem through the air water interface and by the photosynthetic. average concentration of dissolved oxygen as 10 parts per million by weight.

Dissolved oxygen escapes the water body through air-water interface and through respiration of organisms (fish, decomposers, zooplanktons, etc )

The amount of dissolved oxygen retained in water is also influenced by temperature.

Other limiting factors which influence on aquatic productivity are

Transparency:

Transparency affects the extent of light penetration.

Suspended particulate matters such as clay, silt, phytoplankton, etc make the water turbidity. Consequently it limits the extent of light penetration and the photosynthetic activity in a significant way.

Temperature:

The water temperature changes less rapidly than the temperature of air because water has a considerably higher specific heat than air.

Since water temperatures are less subject to change, the aquatic organisms have narrow temperature tolerance limit.