Living organisms live in their respective habitats in ecosystems in the environment. Balance in nature is a situation where the interactions between organisms and their environment produce a steady and balanced ecosystem. Various natural cycles help maintain the balance in nature by recycling natural resources to prevent them from being depleted.

Examples of natural cycles are the nitrogen cycle, carbon cycle and water cycle. The nitrogen gas content is maintained at 78% in the atmosphere. Through the nitrogen cycle, nitrogen which is trapped as plant and animal proteins is returned to the atmosphere.

The Carbon Cycle

Carbon is an important element in carbohydrates, proteins and fats which are important substances for living organisms. Organisms must have enough carbon in order to survive. The amount of carbon in the environment is maintained at equilibrium through the carbon cycle. Carbon dioxide which is a source of carbon in the atmosphere is maintained at 0.03%.

To maintain the amount of carbon dioxide in the atmosphere, the amount released into the atmosphere must equal the amount removed from the atmosphere. Processes which add carbon dioxide into the atmosphere are respiration which is carried out by all living organisms (plants and animal), the burning of fuels and the decay of organic substances by bacteria and fungi. The equation below shows the release of carbon dioxide during respiration.

Food + oxygen → carbon dioxide + water + energy  

Photosynthesis which is carried out by green plants to manufacture food (carbohydrates) is a process which removes carbon dioxide from the atmosphere. Photosynthesis is represented by the equation below:

Carbon dioxide → glucose +oxygen + water

When the concentration of carbon dioxide in the atmosphere is very high, it results in an increase in environmental temperature, global warming and a change in the weather.

Image via Wikipedia

The Water Cycle

Water is an important component of the body. It provides a medium for enzymes to act and is important to the transport systems of plants and animals. The water cycle helps to maintain the water content in the soil, oceans and in the atmosphere through the release of water vapor and in the formation of rain. Water vapor is released into the atmosphere through the respiration of living organisms, transpiration by plants and the evaporation of water from the land, rivers, oceans and lakes.

 

Image via Wikipedia

Water vapor in the form of droplets of water then form clouds in the form of droplets of water then form clouds in the sky. These droplets continue to gather and increase in size and weight. Finally they fall as rain onto the land, seas and lakes.

The water cycle maintains the aquatic habitats of aquatic organisms such as fish and prawns, provides water for rivers, the land, oceans and lakes and also provides water to dissolve minerals in the soil for the absorption by plants.  Rain also makes the weather cool.

The Role of Food Webs in Maintaining the Balance in Nature

Living organisms depend on one another for food and protection. The food relation between organisms with plants providing food for animals is called the food chain. An example of a food chain is shown below:

Grass → eaten by grasshoppers’ →eaten by frogs’ → eaten by snakes

Green plants such as grass are called producers because they can manufacture their own food through photosynthesis. Herbivores such as grasshoppers which feed on producers are called primary consumers. Carnivores which feed on herbivores are called secondary consumers (for example, frogs) and tertiary consumers (for example snakes).

De-composers such as bacteria and fungi are pan of a food chain. They break down organic parts of dead organisms and release useful, simple substances back into the soil to be reused by plants in this way, important elements can be recycled and prevented from being depleted. Food chain also shows the flow of energy from one organism to another in the form of food. A network of interconnected food chains is called a food web.

The light energy from the sun is absorbed by the producer (grass), which then flows to the primary consumers (the rabbits, grasshoppers, birds and rats) and on to the secondary consumers (the lizards, eagles and snakes) and finally to the tertiary consumers (the snakes and eagles). Through this method, all the organisms is an ecosystem can obtain the energy required for their daily activities

Image via Wikipedia

The transfer of energy from the producer to the primary consumer and on to the secondary consumer involves a lot of energy loss in the form of heat. Therefore, only 10% of energy is actually transferred to the next stage. Feeding relationships can be represented graphically in the form of a pyramid.

The base of the pyramid is occupied by the producer which occurs in very large numbers. This is followed by the herbivores which are eaten by smaller numbers of bigger carnivores and this continues until the peak of the pyramid which is occupied by the consumer that is the largest in size. The number of organisms decreases from one stage to the next. Food webs maintain the balance in nature by controlling the number of organisms in each level of the food chain.

Image via Wikipedia

The Effects of Natural Disasters on Balance in Nature

Natural disasters are natural occurrences that bring about changes, cause damage to the environment and destroy the balance in nature. Natural disasters cannot be avoided. After disaster, organisms in an ecosystem adjust themselves to the new environment and continue to survive and maintain the equilibrium. Examples of natural disasters are droughts, floods, typhoons (hurricane) earthquakes and volcano eruptions.

Droughts occur when there is shortage of water due to little or no rainfall in an area. The land becomes dry and during this period (which act as producers in food chains or food webs) cannot survive thus food is not produced. Primary consumers are starved and this affects secondary and tertiary consumers. Finally, it results in the death of organisms.

 

Floods occur due to excessive rainfall and they destroy agricultural crops and properties, cause the drowning of animals and humans and may also spread infectious diseases. Floods also cause soil erosion and landslides, thus affecting the habitats and indirectly the food chains and food webs in ecosystems. Earthquakes cause the collapse of buildings, roads, bridges and change ecosystems. This results in the death of plants, animals and humans thus affecting food chains and webs.

Volcano eruptions release hot lava which kills plants, animals and humans. Dust particles, smoke and acidic gases (for example sulphur dioxide) released by volcano eruptions are accompanied by earthquakes which cause sea beds to vibrate and shift, resulting in floods along coastal areas. Volcano eruptions can change the ecosystem of an area. Lava contains minerals from the earth’s crust which may lead to an infertile area becoming fertile and suitable for agriculture.

Image via Wikipedia

Ways to Maintain the Balance in Nature

Image via Wikipedia

1.     Controlling the excessive use of pesticides: a) Pesticides kill insects, thus affecting the number of herbivores in an ecosystem. This upsets food chains and food webs, resulting in an increase in the number of producers and decrease in the number of primary consumers.

2.     Practicing biological control of pests.

3.     Controlling deforestation:

• Trees are producers which help to maintain the amount of carbon dioxide and oxygen gasses in the atmosphere. Trees provide habitats for many organisms. The uncontrolled felling of trees results in a loss of habitats.
• The water cycle is also affected when trees are felled because rainwater cannot be absorbed by plants from the ground and water vapor cannot be transpired by plants into the atmosphere. This results in less rainfall for many organisms thus affecting food chains and food webs.

4.     Preventing the hunting of animals which may result in certain species becoming extinct.

Image via Wikipedia

5.     Controlling air and water pollution from factories:

• Air pollution affects the rate of photosynthesis carried out by green plants thus affecting the equilibrium of carbon dioxide and oxygen in the atmosphere.
• Air pollution also results in the formation of acid rain which kills aquatic organisms in lakes, rivers and trees, thus affecting food chains and food webs. Water pollution also affects aquatic food webs.

6.     Using substances which are biodegradable can be recycled or reused.

Image via Wikipedia

7.     Reducing the excessive release of carbon dioxide into the atmosphere:

• The burning of forests and fossil fuels releases a large amount of carbon dioxide. An increase in carbon dioxide upsets the carbon cycle, leading to global warming and climate changes.
• Carrying out environmental awareness campaigns in schools and also at society and community levels.

Image via Wikipedia

Info Gallery

High nitrate content in drinking water due to leaching can cause the ‘blue baby syndrome’. It is characterized by the hemoglobin carrying less oxygen, resulting in respiratory failure.

70% of our body weight is made up of water. Humans lose about 1.5 liters of water per day through urine, feces, exhaled air and sweat. A loss of 5% of the body’s total volume of water can lead unconsciousness.

The biological method has been used since way back in 1888. Ladybugs were imported from Australia to control cottony scale insects which were destroying Californian citrus plants.

 

In 1991, more than 500 people were killed when the Pinatubo volcano in the Philippines erupted, releasing millions tones of lava. The surrounding areas were covered with lava three meters high, 100 000 hectares of agriculture areas were destroyed.