8 Science Ch 19 Lesson 3

__________ is the process of one ecological community changing into another.

Ecological succession

_______ is the process of a body of water becoming nutrient-rich.

Eutrophication

Climax communities differ depending on the ______ that they occur in.

biome

During secondary succession, a ______ might develop over time.

climax community

The final stage of succession in a land ecosystem in the ______ which is stable of long periods of time.

climax community

The _______ remains of dead organisms add to the build up of soil.

decomposed

Open fields can become a ______ if they are left undisturbed.

forest

As time passes, more and more soil accumulates.Eventually so much has collected that the water disappears & the area becomes _____.

land

After a volcano erupts, molten ____ cools & hardens into bare rock.

lava

______ spores are carried by the wind & settle on the rock.

lichen

The species include some ________ and ________.

lichens/mosses

Humans contribute to eutrophication when fertilizers or pollution run off into a pond or lake, increasing _______ concentration.

nutrient

As decaying organisms fall to the bottom of a wetland, lake, pond, they add _____ to the water.

nutrients

The first species that colonize new or undisturbed land are ______.

pioneer species

After many years, the soil become deep enough of many different types of ____ to grow.

plants

________ of the same species tend to replace each other over time.

plants

________ in ecological succession that occurs in areas where there is little or no soil.

primary succession

_______ takes place in areas where ecosystems have been disturbed.

secondary succession

________ carried rainwater & streams accumulate on the bottoms of ponds, lakes, & wetlands.

sediments

Broken-down rock & soil from decaying lichens help create _____

soil

Plant parts help build up the _____ layer.

soil

_____ from mosses and fertile settle in thin soil on the side of a volcano, & plants soon sprout.

spores

When these organisms die, their bodies decay & add to the build up of soil, speeding up ______.

succession

Lichen release ____ that break down the rock.

acids

High nutrient levels in freshwater bodies support large populations of ______ & the microscopic organisms,

algae

Freshwater ecosystems change over time in a natural, predictable process called ________.

aquatic succession