Category Archives : Environment

Primary air pollutants and their sources

What are primary air pollutants (PAPs)? Primary air pollutants (PAPs) are those that are emitted directly into the air from sources. Examples – Sulphur dioxide, nitrogen oxides, carbon monoxide, volatile organic matter, particulate matters, lead, ammonia etc. How PAPs impact environment? They can have effects both directly and as precursors of secondary air pollutants (chemicals formed through reactions in the atmosphere), which are discussed in the following section. What are secondary air pollutants? A secondary pollutant is not directly emitted as such, but forms when… Continue Reading »

Ocean Acidification and its effect on marine ecosystem

What is ocean acidification? Since the beginning of the industrial revolution, the release of carbon dioxide (CO2) from humankind’s industrial and agricultural activities has increased the amount of CO2 in the atmosphere. The oceans currently absorb about a third of human-created CO2 emissions, roughly 22 million tons a day.When carbon dioxide dissolves in this ocean, carbonic acid is formed. CO2 reacts with water molecules (H2O) and forms the weak acid H2CO3 (carbonic acid). Most of this acid dissociates into hydrogen ions (H+) and bicarbonate ions… Continue Reading »

Bioindicators – mechanism, uses, advantages and examples

What are bioindicators? A bioindicator is a living organism that gives us an idea of the health of an ecosystem. Some organisms are very sensitive to pollution in their environment, so if pollutants are present, the organism may change its morphology, physiology or behaviour, or it could even die.   What can be a bioindicator? Bioindicators can be plants, animals or microorganisms.   How various bioindicators tell about the environmental health? 1. If toxins are present, certain plants may not be able to grow in… Continue Reading »