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The pond as an ecosystem

2020-02-20T16:04:00.001+05:30

The pond as an ecosystem

Pond is a small body of still freshwater formed naturally or by artificially where algae, aquatic plants, insects, fishes, and birds are live. The complex interactions between the biotic and abiotic components of pond form a self-sufficient and self-regulating system.
The pond is the simplest aquatic ecosystem. Where Algae are eaten by microscopic animals, which are eaten by small fish on which larger carnivorous fish depend. These are in turn eaten by the aquatic birds. Aquatic insects, worms and snails feed on the waste material excreted by animals and the dead or decaying plant and animal of pond and break down into nutrients which aquatic plants can absorb, thus completing the nutrient cycle in the pond. Location, size, depth, water quality, pH of the water and several inorganic and organic substances of a pond influence the pond ecosystem.

pond ecosystem

Structure of pond ecosystem –

Like every ecosystem, pond ecosystem also consists of two major component -

Abiotic component

Biotic component

Abiotic component –

abiotic component of pond ecosystem includes temperature, light, pH of the water and several basic inorganic substances like oxygen, carbon dioxide, nitrogen, phosphorous, Calcium, Sulphur and organic substances like carbohydrates, proteins, lipids etc., make the abiotic components.

Biotic Components

Producers:

This category includes green plants which may be submerged, free-floating or amphibious.
Example - Hydrilla, Ceratophyllum, Vallisneria, Jussiaea, Lemna, Eichornia, Salvinia, Spirogyra, Oedogonium, Chlamydomonas, Volvox, Anabaena etc.

Consumers:

(i) Primary Consumers:

Zooplanktons:

protozoans, rotifiers, Lecane, Crustaceans etc.

Benthos:

Larvae of insects, beetles, small fishes, mites, molluscs etc.

(ii) Secondary consumers:

Insects, water beetles, frogs, fishes etc.

(iii) Tertiary Consumers:

Big fishes eating small fishes belong to this group.

(c) Decomposers:

Several bacteria, fungi and actinomycetes represent this group.
Example: Aspergillus, Saprolegnia, Fusarium, Rhizopus etc.

Food chain and Food web

2020-02-11T17:35:00.001+05:30

Food chain and Food web

Food chain

} Food chains are unidirectional sequence or order of organisms of an ecosystem that the food is passed from one type of organism to other organisms.

} All trophic levels in an ecosystem are connected by transferred of energy.

} Trophic level- The trophic level of an organism is the position it occupies in a food chain. Energy flow of a food chain is unidirectional i.e. From producer through herbivores to carnivores.

} The amount of energy flow decreases with successive trophic level. A large amount of energy (~90%) is lost each trophic level.

} Only about 10% of biomass is transferred from one trophic level to the next one in a food chain.

Type of food chain-

Grazing food chain

} Grazing food chain starts from plants, goes through herbivores and ends in carnivores.

example:

Grass à Grasshopper à Lizard à Hawk

Phytoplankton à Zooplankton à Fish à Snake

} The grazing food chain is divided into 2 type:

i. Predator

ii. Parasitic

Grazing Food Chain

Detritus food chain

} Detritus food chain starts from dead organic matter and ends in inorganic compound.

} Detritivores are certain groups of organisms which feed exclusively on the dead bodies of organism.

Example of Detritus food chain:

} Leaf litterà Algae àCrabs à Small fish à Large fish

(Mangrove Ecosystem)

} Dead Organic Matter à Fungi à Bacteria

(Forest Ecosystem)

Detritus food chain

Food web

} In nature, each organism may obtain food from more than one tropic level. So food chains are found interconnected and usually form a complex network known as food web.

} Food web is a network of food chains.

} In food web organisms have a number of options of eating and being eaten at each trophic level.

Food Web

Significance of food chain and food web

} Play significance role in Energy flow and Nutrients Cycling.

} Maintain Ecological Balance or Stability of the Ecosystem.

} Biological magnification of some chemicals.

Thermal comfort

2020-02-05T22:26:00.001+05:30

Thermal comfort

Human thermal comfort is a satisfaction with the surrounding thermal conditions. Thermal comfort is defined as “that condition of mind which expresses satisfaction with the thermal environment and is assessed by subjective evaluation (ANSI/ASHRAE Standard 55-2010). Thermal comfort is highly subjective to person to person. It is depends on different factor such as the air temperature, relative humidity, radiant temperature, air velocity, metabolic rates, and clothing levels and each individual physiology, so it is difficult to measure.

The six factors affecting thermal comfort are both environmental and personal.

Determined of the thermal comfort is essential, when designing a structure that will be occupied by people. Thermal comfort is important for health and well-being as well as productivity. A lack of thermal comfort causes stress among building occupants. When they are too warm, people can feel tired; when too cold, they will be restless and distracted. Thermal comfort is calculated as a heat transfer energy balance. Heat transfer through radiation, convection, and conduction are balanced against the occupant’s metabolic rate. The heat transfer occurs between the environment and the human body. If the heat leaving from body is greater than the heat entering the body, the thermal perception is “cold.” If the heat entering the body is greater than the heat leaving from the body, the thermal perception is “warm” or “hot”.

The human body, considered as a thermodynamic system. This system requires, in healthy conditions, to maintain a constant internal temperature around 37±0.5°C, otherwise the functionality of important organs like liver, spleen, etc, may be severely damaged. So, People working in uncomfortably hot and cold environments are more likely to behave unsafely because their ability to make decisions and perform manual tasks deteriorates and the workers' ability to concentrate on a given task may start to drop off and increases the risk of errors occurring in hot environment. Based on the researches done on thermal comfort it can be conclude that thermal comfort makes a big difference to productivity. So now it is most important to know why thermal comfort is important and what we can do to achieve thermal comfort.

GREEN SOLVENTS

2020-02-03T19:37:00.000+05:30

GREEN SOLVENTS-

Green solvents are environmentally friendly solvents, which are derived from the processing of agricultural crops.Green solvent or also known as bio-solvent is typically an alternative to the conventional solvents which is available in the market. Green solvents reduces the environmental impact resulting from the use of organic solvents in chemical production.

Some important green solvent which are currently available in the industry are-

1. Ethyl lactate

2. Glycerol

3. Supercritical fluids

4. Ionic liquid

5. Bio ethanol

6. Terpene

7. Polyether

8. Siloxane polymer

9. Dibasic esther etc.

GENERAL PROPERTIES OF GREEN SOLVENTS-

Green solvent has a lower environmental impact compared to other conventional solvents. Some general properties of green solvent are-

1. Green solvents are completely biodegradable.

2. Green solvents are can be easily recycled.

3. Green solvents are non-corrosive.

4. Green solvents are non-carcinogenic.

5. Green solvents are produced from renewable sources.

6. Green solvents are environmental friendly solvent.

PRODUCTION METHODS OF GREEN SOLVENT-

The four methods which are generally used for producing green solvents are:

1. Substitution of hazardous solvents with ones that show better environmental, health and safety properties.

Example: Ability to biodegrade or ability to reduce ozone depletion.

2. Production of green solvents using renewable re-sources.

Example: Fermentation of agricultural waste to produce ethanol.

3. Substitution of organic solvents with environmentally harmless supercritical fluids.

Example: Usage of supercritical CO2 instead of CFC.

4. Substitution of organic solvents with ionic liquids of low volatility.

Example: Lowering emission of volatile compounds to the atmosphere. (7)

Remote sensing

2020-02-02T21:05:00.000+05:30

What is Remote sensing

Remote sensing is defined as the art and science of obtaining information about an object without being in direct physical contact with the object. It is a scientific technology that can be used to measure and monitor important biophysical characteristic and human activities on earth. Remote sensing is also defined as the measurement or acquisition of information of some property of an object or phenomenon, by an recording device that is not in physical or intimate contact with the object or phenomenon under study. So, remote sensing is the non contact recording of information from the ultraviolet, visible infrared and microwave region of the electromagnetic spectrum by means of instrument such as cameras, scanner, laser, linear arrays and area arrays located on platforms such as aircraft or spacecraft and the analysis of acquired information by mean of visual and digital image processing.(Jensen J. R.M 2014)The sensors collect data in the form of images and provide specialized capabilities for manipulating, analyzing, and visualizing those images. Remote sensed imagery is integrated within a geographicinformation system (GIS). A geographic information system (GIS) is a computer-based tool for mapping and analyzing feature events on earth. GIS technology integrates common database operations, such as query and statistical analysis, with maps. GIS manages location-based information and provides tools for display and analysis of various statistics like characteristics and distribution of vegetation types.

In India, Remote sensing is extensively used for weather forecasting and warns people about impending cyclones. It can be used to study deforestation, ecology, degradation of fertile lands, pollution in atmosphere, desertification, natural hazard, hydrology, eutrification of large water bodies and oil spillage from oil tankers etc. Remote sensing can be used to study damages caused by earthquakes, volcanoes, landslides, floods and melting of ice in polar regions. In Natural Hazard assessment, remote sensing data can be used to assess the impacts of a natural disaster and create preparedness strategies to be used before and after a hazardous event. Many times remote sensing will be helpful to predict the occurrence of natural hazards. Remote sensing data is useful in obtaining up-to-date land use and land cover of large areas at any given time and also monitor changes that occur from time to time. This information is used by regional planners and administrators to frame policy matters for all round development of the region. (Jensen J. R.M 2014)

The most significant feature of remote-sensing satellite technology is that it makes possible the repeated survey of vast areas in a very short time even if the area is otherwise inaccessible. The photographs and other data collected by Indian remote sensing satellites, IRS-IA and IRS-IB, have been used for many practical purposes. The important applications of remote-sensing satellites are : Groundwater surveys; Forest surveys; Preparing wasteland maps; Drought assessment; Estimation of crop yields; Detection of crop diseases; Survey for detecting coal, oil and ores; and Detection of potential fishing zones of the sea. The remote sensing satellites are also used for doing “spying work” for military purposes.

REFERENCE

1. Jensen R.J., Remote sensing of the environment: An Earth Resource Perspective , Pearson,Second edition,2014. ISBN:978-93-325-1894-0. PP:2-457

ECOLOGY AND ECOSYSTEM (Definition, Type, Components and Function)

2020-01-24T12:38:00.000+05:30

ECOLOGY AND ECOSYSTEM
(Definition, Type, Components and Function)

ECOLOGY

The term ecology was coined by Earnst Haeckel (1869).
The study of ecosystem is defined as Ecology. Therefore ecology deals with the study of organisms in their natural home interacting with their surrounding.

ECOSYSTEM

The term ecosystem was coined by a British ecologist A. G. Tansley (1935).
Ecosystems is a self regulating, self sustaining and functional unit of nature where living organisms (biotic component) interacting with each other and with their non living environment (abiotic factor) exchanging energy and matter.

Types of Ecosystem-

According to environment-

1. Terrestrial Ecosystem-

A terrestrial ecosystem is an ecosystem found only on landforms. Six primary terrestrial ecosystems are tundra, taiga, temperate deciduous forest, tropical rain forest, grassland and desert.

2. Aquatic Ecosystem-

An aquatic ecosystem is an ecosystem in a body of water. Two main type of aquatic ecosystem are-

Marine ecosystem (oceans, coral reefs, estuaries).

i. Cover ~71% of earth surface.

ii. Generate 32% of the world’s net primary production.

iii. Marine ecosystem is divided into 4 zone-

§ The Oceanic Zone (Part of ocean where animal live).

§ The Benthic Zone ( zone where many invertebrates live).

§ Neritic Zone (include estuaries, salt marshes, coral reefs, lagoons and mangrove swamps).

§ Abyssal Zone.

Freshwater ecosystem (ponds, lakes, rivers, and wetlands etc.)

i. Covers ~0.78% of earth’s surface.

ii. Generate nearly 3% of its net primary productivity.

iii. Contain ~41% of world’s known fish species.

iv. Freshwater ecosystem (ponds, lakes, rivers, and wetlands etc.)

v. Two basic types of fresh water ecosystem-

§ Lentic- Slow moving water, including pools, ponds and lake.

§ Lotic- faster moving water, for example stream and rivers.

According to the degree of human intervention –

1. Natural Ecosystems :

These ecosystems are capable of operating and maintaining themselves without any major interference by man. Man has not intervened in their formation, such as forests, lakes, deserts etc.

2. Artificial Ecosystems :

These are maintained and manipulated by man for different purposes. such as dams, parks, gardens etc.

Component of ecosystem

Ecosystem is composed of both abiotic (non-living) and biotic (living organism) components.

Abiotic Component

Physical or chemical components

- Like temperature, Water, Soil, Light, Humidity, Pressure etc.

Inorganic Compounds

- Like minerals, Atmospheric gases etc.

Organic Compounds

- Includes organic substances present in dead bodies of plants and animals.

Biotic Components (on the basis of mode of nutrition)

Producers / Autotrophs

- Organism which carry out Photosynthesis. E.g.- plants, algae etc.

Consumers / Heterotrophs

- Organism which derive their food directly and indirectly from the produces. Consumers are also can be divided into Primary Consumers (Herbivores, Directly feed on producer), Secondary consumers (Primary Carnivores, They prey upon Herbivores), Tertiary Consumers (Secondary Carnivores, They feed on Primary Carnivores) and Omnivores (They feed on both plants and animals).

Decomposers/ Micro Consumer/ Saprobes

- They obtain their nutrition from organic remains. E.g.- fungi and some bacteria etc.

Function of ecosystem

Fixation of energy (Productivity).
Energy flow through different tropic level within the ecosystem.
Relationship of producers and consumers.
Decomposition and cycling of nutrients.

ECOLOGICAL PYRAMID

2019-11-26T14:10:00.000+05:30

ECOLOGICAL PYRAMID

Ø The use of Ecological Pyramid was first described by Charles Elton in 1927.

Ø Ecological Pyramids are graphical representation of the number of individual present or amount of biomass synthesized or amount of energy stored at successive trophic levels in an ecosystem.

Ø Ecological Pyramids are starting with producers at the base and successive trophic levels forming the apex are known as an Ecological pyramid.

Types of Ecological Pyramids-

Pyramid of numbers-

Ø Graphical representation of numerical strength of various populations in different trophic levels per unit area of an ecosystem.

Ø Usually upright.

Ø Inverted and spindle shaped only in some parasitic food chain and tree ecosystem.

2. Pyramid of Biomass-

Ø Biomass is the total weight of living matter per unit area.

Ø In terrestrial ecosystem, Biomass decreases from the producer level to the consumer level. So, the pyramid of biomass of terrestrial ecosystem is upright.

Ø In aquatic ecosystem producer are small organisms, so their biomass is less. The primary and secondary consumers are bigger, so their biomass is more. Therefore pyramid of biomass of aquatic ecosystems are inverted.

3. Pyramid of energy-

Ø In an ecosystem energy flows from the producer level to the consumer levels.

Ø During energy flow 80-90% of energy lost at each trophic level and only 10% of energy is transferred to the next trophic level.

Ø Therefore pyramid of energy is always upright.