(a) Increase in the population of grasshopper.
(b) Migration or death of snakes due to food scarcity.
(c) The ecological balance is distributed.
(d) Decrease in the production of grass.

It is necessary to conserve our environment to prevent depletion of natural resources and environmental damage, thereby sustaining life.

Grassland ecosystem:
Grass \(\longrightarrow \) Grasshopper\(\longrightarrow \)Frog\(\longrightarrow \) Snake
Pond ecosystem:
Algae \(\longrightarrow \) Small Fish/shrimp\(\longrightarrow \) Medium Fish \(\longrightarrow \)Large fish/crane/duck

It is a complex web of many interconnected food chains, involving many organisms. There is more than one organism at a particular trophic level. Food web is real life situation.

Different components of food are changed to simpler substances by digestive enzymes and these enzymes are very much specific in nature and action. Similarly substances are broken down by bacteria and saprophytes. They are also very specific in action and break down of the particular substance. Therefore, some substances are biodegradable and other are non-biodegradable.

Normally a lake has more diverse forms of life and hence a larger number of food chains. This leads to natural cleaning. Thus, the ecosystem is more stable. The aquarium has a very limited number of food chains and unable to sustain itself. But, sometimes there is excessive growth of algae in lake. Then it also needs to be cleaned.

Energy of herbivorous never comes back to autotrophs as flow of energy is always unidirectional. So once it passes the trophic level it is no longer available to the previous level.

A pond or a lake has its own natural systems to maintain its ecosystem. Due to this, ponds or lakes normally do not need to be cleaned. An aquarium is a man-made ecosystem which has a very small space. The abiotic components are not supplied naturally to the aquarium. So, an aquarium needs frequent cleaning so that the living beings in it can survive.

If all the waste is biodegradable, then there will be no accumulation of waste and the Earth would be a cleaner place to live. But if, this biodegradable waste is too large in amount then its slow degradation may lead to air pollution (due to release of gases) as well as water and land pollution.

The following are the issues caused by non-biodegradable waste:
Non-biodegradable waste does not decompose. They accumulate in the environment and cause biomagnification; as a result of this accumulation, they pollute soil and water; they pollute the environment.
If such wastes are burned, they pollute the air.
Non-biodegradable wastes, such as pesticides, deplete soil fertility as they penetrate it. The soil's pH level becomes unsuitable for plant growth. Some substances contaminate the environment, causing harm to living organisms.