For most of human history, we have received many ecosystem services free and have taken them for granted.These include clean air, clean water, pollination, and flood control by wetlands.Compared with a century ago, these types of ecosystem services seem to be
A) unchanged.
B) degraded in quality.
C) improved in quality.
D) more available.
E) not measurable.

Question

Quizplus · Accepted Answer

Human activities such as pollution, deforestation and urbanization have significantly degraded the quality of ecosystem services such as clean air, clean water and flood control by wetlands. Therefore, compared with a century ago, these ecosystem services have deteriorated in quality.

For Most of Human History, We Have Received Many Ecosystem