Important question regarding Geography of environment.

In this Geoshortqa we are going to know about some important question regarding Environment.

1. What do you mean by Ecology?

Ans :- Eceology is the science of studying the mutually interdependent and interrelated relation and correlation between organisms and their physical environment.

Important of Ecology, Geoshortqa

 

2. Who first coin the term ecology and which year?

Ans :- 1869, German biologist Ernest Haeckel first coin the term ecology.

3. Definition the term Ecology.

Ans :- The term Ecology which was derived from 'Oikos' meaning 'habitat' and 'Logos' meaning' the 'study of'.

4. What do you mean by Ecological Niche ?

Ans :- The role that an organism palys in the ecosystem is known as its Ecological Niche.

5. What are the labels of organization in an ecology?

Ans :- The equality of humans is broadly divided into six levels

Individual :- Organism is an individual living being that has the ability to act all function independently. It is a body made of organ tissues and cells.

Population :- Population is a group of organism usually of the same species, occupying and area during a specific time

Community :- A community has one or several species. 

Ecosystem :- It is a complex system of relationship among the abiotic and biotic component of an area. The geographical, climatic and soil characteristics from its non-living component.

The the living part of the ecosystem is referred to as its biotic component.

Ecotone :- It is a zone of transition between two or more diverse ecosystems.

Example Mangrove forest represents and ecotone between and marine ecosystems.

Biosphere :- Biosphere is zone on earth where life can exist. It is a highly interacting and interacting of atmosphere, hydrosphere and lithosphere.

 

Biome :- The territorial part of a biosphere is divided into various regions called Biomes. 

They are characterised by unique and distinctive visitation animal life, soil type etc.

6. What are the functions of an ecosystem?

Ans :- The functions of an ecosystem of classified into three categories. 

A. Energy flow :- Energy is the basic source of all the metabolic activities. The energy is an ecosystem flows from the bottom producers to top consumers ( Trophic level).

Energy flow in an ecosystem is unidirectional.

Something about Tropic level

Tropic Level :- Tropic levels describe how the various members of an ecosystem are connected with each other based on their nutritional needs.

There is a loss of energy as the energy travel from lower tropic level to the higher tropic levels.

Only 10% of the energy of and tropic level is transferred to the next tropic level.

Usually is an ecosystem, there can be four or five trophic level.

Producers : Autotroph

Primary consumers : Herbivores

Secondary consumers : Primary Carnivores

Tertiary consumers : Secondary Carnivores

Quarternary consumers : Top Carnivores

The trophic level interaction involves the following 

1. Food Chain :- A sequence of organisms that feed on each other is known as food chain.

There are two types of food chains

i) Grazing food chain :- The consumers which start the food chain by eating the plants from the land ,constitute the grazing food chain.

Like an example a terrestrial ecosystem, grass is eaten by caterpillar, which is eaten by a lizard and the lizard is eatan by the snake. In an aquatic ecosystem, the phytoplanktons are eaten by the zooplanktons, which is eaten by fishes and fishes by pelicans.

ii) Detritus food chain :- It starts from the dead organic matter of decaying animals and plants which are consumed by the micro-organisms and then to detritus feeding organisms called detrivores or decomposers.

 A food chain represents only a part of food chain and is a simple and isolated relationship, which seldom occurs in an ecosystem. A food web shows all possible transfers of energy and nutrients among the organisms. 

So, it becomes essential to study the more realistic mechanism of a food web.

2. Food Web :- A food web (or food cycle) is a natural interconnection of food chains and a graphical representation (usually an image) of what-eats-what in an ecological community.

The food web tells us about the pathways through which the organisms take their nutrition. Thus, a food web illustrates the different pathways or all possible transfers of energy and nutrients among the organisms in an ecosystem.

3. Ecological Pyramid :-In an ecosystem, trophic levels are expressed in the form of ecological pyramids. The green plants- the producers, utilise energy directly from sunlight and convert it into matter. A large number of these organisms form the most basic, or first 'trophic level' of the food pyramid. The herbivorous animals that eat plants are at the second tophic level and are called primary consumers. The predators that feed on them form the third trophic level and are known as secondary consumers. 

Only a few animals form the third trophic level consisting of carnivores at the apex of the food pyramid. This is how energy is used by living creatures and flows through the ecosystem from its base to the apex. Much of the energy is used up in activities of each living organism. 

There are various types of ecological pyramids like

 (i) Pyramid of Number :- which shows the relationship between the number of primary producers and consumers of different levels. As it is difficult to count the number of organisms at a given trophic level, so pyramid of biomass is used. 

(ii) Pyramid of Biomass :- indicates the weight of biomass of the living organisms in an ecosystem. Biomass is weighted in g/m². It overcomes the problem of counting the number of organisms.

(iii) Pyramid of Energy :- shows the flow of energy from one trophic level to the next. It reflects the laws of thermodynamics, with the conversion of solar to chemical and heat energy at each trophic level. The energy pyramid is always upwards because only 10% ehergy is transferred from the bottom most trophic level to the top most trophic level. e.g. If the producer plant produces an energy of 1000 calories, then only 100 calories will reach the next trophic level and so on. The usable energy thus decreases as we move from the lowermost trophic level to the top most trophic level.

B. Nutrient cycling :- 

Nutrient Cycling All of us are dependent on energy flows and the nutrient circulation that occurs through the ecosystem. The nutrient cycling describes how the nutrients circulate from non-living beings to living beings and then back to non living beings. These linked processes can be depicted as the various cycles. The cycling of nutrients is important for survival of organisms and carrying out vital functions of the ecology of a region. 

e.g. During photosynthesis carbon dioxide is taken up by plants and oxygen is released, animals depend on this oxygen for their respiration, similarly, the water cycle depends on the rainfall, which is necessary for plants and animals to live. 

The energy cycle recycles nutrients into the soil on which plant life grows. This occurs in a circular fashion and this circular flow is knows a Biogeochemical Cycle. 

Biogeochemical Cycles :- 

The cycles, which help in circulating the nutrients are the water cycle, the carbon cycle, the oxygen cycle and the nitrogen cycle.

Water cycle or hydrological cycle :- Water Cycle or Hydrological Cycle The water cycle, also known as the hydrological cycle or the hydrologic cycle, describes the continuous movement of water on, above and below the surface of the Earth. VWater is transferred to the atmosphere from the Earth from rivers, lakes, oceans, underground sources, plants and animals. This water gets condensed in the upper troposphere and falls on the Earth as precipitation in the form of rain, snow, hail, dew, sleet, frost etc. There are many reservoirs of water on Earth like the ocean, atmosphere, lakes etc.Water is fundamental to respiration and photosynthesis. It also plays an important role in agriculture, drinking, transportation etc. When it rains, the water runs along the ground and flows into rivers or directly into the sea. A part of the rainwater that falls on land percolates into the ground. This is stored as underground water. Water is used from the ground by plants alongwith the nutrients from the soil. The water is transpired from the leaves as water vapour and returned to the atmosphere. This process is known as Transpiration. The transfer of water from water bodies to the atmosphere is known as evaporation. As water vapour is lighter than air, it rises and forms clouds. Winds blow the clouds for long distances and when the clouds rise higher, the vapour condenses and changes into droplets, which fall on the land as rain. Though this is an endless cycle on which life depends, human activities are making drastic changes in the atmosphere through pollution and other harmful effects, which is altering the hydrologic cycle on the surface of Earth. 

Carbon cycle  :- Carbon is the fourth most abundant element in the universe and is absolutely essential to life on Earth. It is the basic element of all living organisms which are made of carbon. It -is also a part of the ocean, air, and even rocks. The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere and atmosphere of the Earth.

The major sources of carbon on Earth are- Atmosphere (as carbon dioxide gas). Deforestation, Combustion, Volcanic eruptions, Respiration, Animal ranching, Paddy cultivation, Bio-decomposition etc.

Carbon is important constituent of organic compounds found in living beings in form of carbohydrates, fats proteins, nucleic acids. Plants require carbon dioxide fo photosynthesis, Carbon is the main component of biological compounds as well as a major component of many minerals such as limestone. Carbon is a building block of both plant and animal tissues. In the atmosphere, carbon occurs as carbon dioxide (CO,). In the presence of sunlight, plants take up carbon dioxide from the atmosphere through their leaves and combine carbon dioxide with water, which is absorbed by their roots from the soil. In the presence of sunlight they are able to form carbohydrates that contain carbon. This process is known as photosynthesis. In this process, plants release oxygen into the atmosphere on which animals are dependent for their respiration. Plants help in regulating and monitoring the percentage of oxygen and carbon dioxide in the Earth's atmosphere. Life on Earth thus depends on the oxygen generated through this cycle. Now, herbivorous animals feed on plant material, which is used by them for energy and for their growth. Both plants and animals release carbon dioxide during respiration. They also return fixed carbon to the soil in the waste they excrete. When plants and animals die, carbon returns to the soil. These processes complete the Carbon cycle.

Nitrogen cycle  :- Nitrogen cycle represents the circulation of nitrogen in various forms. Nitrogen, a component of proteins and nucleic acids, is essential for the occurence of life on Earth. Although 78% by volume of the atmosphere is nitrogen gas, this abundant reservoir exists in a form unusable by most organisms. Through a series of microbial transformations, nitrogen is made available to plants, which in turn sustains all the life on Earth.

The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates through the atmosphere, terrestrial and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes. Important the nitrogen cycle include fixation, in processes ammonification, nitrification and denitrification. Nitrogen needs to be 'fixed', that is, converted to ammonia, nitrites or nitrates, before it can be taken up by plants. Conversion of urea and uric acid to ammonia is known as Ammonification. Nitrification is the process that converts ammonia to nitrite and then to nitrate. Ammonia and ammonium ions are oxidised to nitrites or nitrates by groups of specialised bacteria. Denitrification is the reduction of nitrates back into nitrogen gas (N2). Carnivorous animals feed on herbivorous animals, that feed on plants. When animals excrete waste, this waste material is broken down by worms and insects. These small 'soil animals' break the waste material into smaller bits on which microscopic bacteria and fungi can act and this material is thus broken down further into nutrients that plants can absorb and use for their growth. Thus, nutrients are recycled back from animals to plants. Nitrogen fixing bacteria and Tungi in soil gives this important element to plants, which absorb it as nitrates.

The nitrates are a part of the plant's metabolism, which help in forming new plant proteins. This is used by animals that feed on the plants. The nitrogen is then transferred to carnivorous animals when they feed on the herbivores. Similarly the bodies of dead animals are also broken down into nutrients that are used by the plants for their growth and the nitrogen cycle is completed.

Oxygen cycle :- Oxygen in the atmosphere is about 21%, and it is the second most abundant gas after nitrogen. It is mostly utilised by living organisms, especially man and animals in respiration. Oxygen is also the most common element of human body. Oxygen on Earth is mainly formed of Silicate and oxide minerals of the crust and mantle which are the largest reservoirs of oxygen, oxygen is also found in water, biological molecules like carbohydrates, proteins, nucleic acids and lipids. The main driving factor of oxygen cycle is photosynthesis, which utilises carbon dioxide and releases Oxygen.

Oxygen is useful to us in many ways. Plants, humans and animals use oxygen to respire. When oxygen is mixed with acetylene, it can create a very hot flame and is used in welding of metals. Liquid oxygen can make a hot flame with other propellants for rocket engines. Oxygen is also used in smelting metal from ore. Oxygen dissolved in water is responsible for the sustenance of the aquatic ecosystem. Oxygen is taken up by plants and animals from the air during respiration. The plants return oxygen to the ațmosphere during photosynthesis and the oxygen cycle is completed.

C. Ecological succession :-

  

Succession is the process of unidirectional change in the growth of vegetation. Succession occurs when a community replaces another community due to progressive changes which then results in the establishment of the most stable state which is the climax community. 

The first plant to colonise an area is called the pioneer community and the last stage is known as the climax community. The stages which lead to transformation from the pioneer community to the climax community are known as seres. Succession is characterised by increase in productivity, reposition of nutrients from reservoirs, increase in diversity of species and formation of complex food webs.

The succession is classified into two groups :-

(i) Primary Succession :- 

The primary succession occurs as a result of colonisation of a few pioneer species like microbes, lichens and mosses etc. These species transform the habitat into conditions that are favourable for their growth and development. Subsequently new and additional organisms arrive at the site and produce organic matter through the death and decay of pioneer species. The organic matter produced is used to release nutrients in the soil and makes conditions favourable for the further growth and development of other species. As the community continues to grow, competition increases and it becomes more and more diverse and leads to colonisation of invasive species, which replaces the preceding community. 

(ii) Secondary succession :-

Secondary succession takes place when the plants recognise an area where the climax community has been disturbed due to some natural hazard or man made activities. A community can be partially disturbed due to flood, drought, fires, storms, agriculture etc. The damaged land is first invaded by species of grasses that can survive in bare soil. These grasses then are joined by tall herbaceous plants which dominate the area for some years alongwith mice, rabbits and seed eating birds. Finally, trees come up in this area and over many years, the trees are finally fully developed and the landscape is transformed into a forest. Secondary succession is relatively faster than the primary succession because it occurs on already developed soil which has been partially damaged or destroyed by any natural or man-made calamity.