Question

A man-made ecosystem is
a. Less in diversity
b. More in diversity
c. Man does not make ecosystem
d. More stable than natural ecosystem

Answer 1

Hint: The populations of organisms interact with each other in biological communities as no biotic community can live in isolation. It lives in an environment that supplies its material and energy requirements. So an ecosystem is formed by a biological community interacting with its non-living environment.

Complete answer:
The man-made ecosystems are artificial ecosystems that are also known as agroecosystems. These types of ecosystems are variable in their duration and stability.

The man-made ecosystems are simple and less efficient because of less diversity of organisms. They do not have the diversity of the natural ecosystems. A diversified ecosystem is more stable because some species of organisms would survive even if they are affected by certain pests and pathogens.

A monoculture would be destroyed completely by drought, floods, pests, or pathogens whereas a natural diversified ecosystem has capacity for many adjustments.

The important man-made modifications in the biotic community are brought about by the cultivation of plants, domestication of animals and use of fire. Man has developed croplands for growing pulses, cereals, oilseeds and fodder crops by cutting very large areas of forests and grasslands. Generally one crop is grown in a field and there is a strong selective pressure to reduce diversity. However some weeds grow in the crop field, their number is quite less as compared to natural grasslands and also the animal population of such lands includes nematodes, insects, pests, pollinators, birds and rodents.

Hence, the correct answer is option (A).

Note: An ecosystem is an area where the inputs and outputs can be studied across its boundaries and is treated as a separate entity. The ecosystems are not strictly separated and isolated as their boundaries are indistinct and overlapping.