a.

how easily water passes through the soil

b.

the proportion of air in the soil

c.

the proportion of water the soil holds

d.

how well water rises up the soil

a.

soil

b.

water

c.

wildlife

d.

air

a.

a number of individuals of a given species

b.

groups of different organisms living in a habitat

c.

existing species in an abandoned farmland

d.

the dominant species in the habitat

a.

Death

b.

Commensalism

c.

Competition

d.

Migration