Question

According to Robert constanza, 50% of the total cost of ecosystem goes to
A. Climate change
B. Soil formation
C. Recreation
D. Nutrient cycling

Answer 1

Hint: Pioneer species are those that invade the bare area. Rocks dissolve by the acid produced by lichens. Helping in weathering of rocks and soil formation. These later pave the way to very small plants like bryophytes. Which can take hold of a small amount of soil. They are with time succeeded as bigger plants, and after several ages, ultimately a stable climax forest is formed. If the environment is stable, the climax community remains stable. With time xerophytic converts into a mesophytic one.

Complete answer:
A. Climate change: due to increasing carbon dioxide absorption from the atmosphere. The ocean mitigates global warming. This is due to a biological and chemical change in seawater. Cycling is important for sustaining the environmental system. Climatic change might alter the balance.
B. Soil formation: soil develops gradually as rock weather and organic matter degrades. Pioneers that initiate succession must be able to establish and grow on substrates that are nutrient-poor and often have a very disturbing climate. Moist extreme sites are exposed to further vegetation development. Sites richer in mineral nutrients which may contain some residual organic soil such as the depositional zones of glacial moraines are often colonized by herbaceous species and grasses with faster growth rates. Primary succession proceeds slowly because early colonists often must transform the environment before the other establishes.
C. Recreation is the scientific study of environmental impacts resulting from recreational activity in protected natural areas.
D. Nutrient cycling: The movement of nutrient elements thin e various abiotic and biotic components of the ecosystem is called nutrient cycling.

Hence, the correct answer is option (B).

Note: Robert constants and his colleagues give price tags for nature's life support services recently. Researchers have put an average price tag of 33/trillion on these fundamental services that provide us basic things. And these things are taken freely as they are free of cost. This is twice the value of global gross national product income. The soil formation takes 50% and contributes to other services like nutrient cycling and recreation are less than 10% each. The cost of climate regulation and habitat for animals is 6% each.