Insects as Bioindicator of Environmental Pollution

What is Environment?The term environment comes from the

French word “environ” and means everything that surround us.

The totality of the surrounding conditions for comfortable living of organism.

Environment is the area in which we live.

What is Environmental Pollution?

Pollution is the introduction of contaminants into natural environment that cause adverse change in environment. Few types of pollution are following:

I. Water PollutionII. Air Pollution III. Soil PollutionIV. Noise PollutionV. Thermal Pollution

What are Bioindicators?

Bioindicators are species that can be used to monitor the health of an environment or ecosystem.

Such organisms can be monitored for changes (morphological, physiological, or behavioral) that may indicate a problem within their ecosystem.

Bio indicators can tell us about the cumulative effects of different pollutants in the ecosystem.

E.g. Caddisfly (order Trichoptera) used as an indicator of water quality.

Characteristics of Good Bioindicator

Abundance, wide distribution Simple procedure of identification and

sampling High tolerance for the pollutants analyzed Quick response towards the change in their

environment Taxonomically well documented and stable Easy and cheap to survey

Bio-indicator Groups of Insects1. Dragonflies and

damselflie2. Mayflies3. Caddisflies4. Bugs5. Stoneflies6. Midges7. Honey bees

8. Beetles 9. Collembolans10.Lepidopterans 11.Ants 12.Syrphidfly

Dragonflies and Damselflies

Dragonflies and damselflies (known collectively as the “Odonata”) are an important group in biological water quality monitoring, as they are particularly sensitive to pollution.  

Mayflies Mayflies (Ephemeroptera) larvae are recognized

worldwide for their sensitivity to oxygen depletion in running waters, and are therefore commonly used as bioindicators in many monitoring programs.

Mayflies inhabiting fresh waters like lakes and ponds.

Caddisflies

Caddisflies (Tricoptera) are the group of insects whose larva occur in all type of fresh water. Particular species are sensitive to water pollution and that is why they are used as bio indicator of water purity.

Stoneflies

Stonefly (Plecoptera) larvae can only live in clean water, these flies indicate high oxygen water.

Bugs

Bugs belong to order hemiptera, many families like Corixidae, Nepidae, Notonectidae, Pleidae, Belostomatidae, Gerridae, Veliidae and Mesoveliidae are also act as bioindicator to determine the quality of water.

Midges Species of Chironomidae (Order: Diptera) are widely

used as bioindicators of water quality, since their larvae undergo morphological deformities when in contact with water contaminated with chemicals

Midges are also used to calibrate or forecast the changes in temperature

Honey bees The honey bees (Hymenoptera) act as bio

indicator of environment in two ways as it signals via high mortality rates the presence of toxic molecules or via residues in honey, pollen and larvae the presence of heavy metals.

Beetles Beetles (Coleoptera) belong to family Carabidae

are important predators. They also participate in biological control and

biological monitoring of pollution from oil, Sulphur, Carbon dioxide and insecticides.

Beetles from family Scarabeaidae have high potential as environmental indicator in forest area or agricultural crops.

Collembolans

Collembolan are primitive insects that have influence on soil fertility by microbial activity stimulation.

They are very sensitive to change in soil caused by pollutant such as heavy metals, pesticides and soil acidification in agricultural crops.

Lepidopterans Some lepidopteran groups are used as

environmental indicators by heavy metals and carbon dioxide in locations close to industrial and even within urban areas.

Ants Ants are very sensitive to human impact, and could be

used as environmental indicators in different ecosystems depending on the degree on environmental change, and many species extinct of site.

Syrphidfly These flies belong to family syrphidae, one of the

largest family of Diptera has wide distribution and well known taxonomy and its larvae require different environmental conditions, which make these flies good bio indicator.