Ecology: (Studying Organisms In Ecosystems)

Question 1

Climate:

Answer 1

•climate: refers to the average weather conditions in particular region over a period of time, usually 30 years or more.
•climate is determined by temperature and rainfall.
•temperature and rainfall are influenced by:
-unequal heating of the earth.
-local geography.
-snow/ice cover.
-proximity of large bodies of water.

Question 2

Biomes (1):

Answer 2

•biomes (large ecosystems) are plotted based on annual temperature and annual precipitation.
•patterns suggest than an increase in both temperature and precipitation are related to an increase in biodiversity.
•each biome is characterized by unique biotic and abiotic characteristics.

Question 3

Biomes (2):

Answer 3

•terrestrial biomes- on land.
•aquatic biomes- lakes, rivers, estuaries (where river flows into the ocean), coral reefs, intertidal zones (where an ocean meets the land).
•there are gradual transitions from one biome to the next.

Question 4

Habitats:

Answer 4

•within biomes and vegetation zones are different habitats, each with its own set of organisms and abiotic conditions.
•the range of a population/species is defined as the geographical area where the population or species is found.
•organisms do not necessarily live throughout this range, but do live within this range.

Question 5

Niche:

Answer 5

•the role that members of a species play in a community and the total range of biotic and abiotic requirements that its members need in order to survive.
•could think of a habitat as “street address” and niche as “job in community”.

Question 6

Aquatic ecosystems:

Answer 6

•littoral- is close to the shore.
•benthic- bottom substrate, lower levels of a body of water.
•profundal- deep zone no light penetration.
•limnetic- open, well lit surface waters.

Question 7

Habitats and niches WITHIN ecosystems:

Answer 7

•in an ecosystem, such as a lake, vertical stratification (layering) of water occurs due to conditions such as different amounts of light and nutrients.
•creates different habitats and niches.
•biodiversity can vary greatly from one area to the next.

Question 8

Limiting factors:

Answer 8

•factors limiting growth in ecosystems: populations cannot grow in an unlimited fashion for sustained period of time.
•there are abiotic and biotic limiting factors that control the number of individuals in a population.

Question 9

Abiotic limiting factors:

Answer 9

•soil type.
•moisture.
•humidity levels.
•temperature range.

Question 10

Biotic limiting factors:

Answer 10

-Competition:
•intraspecific competition— within a population.
•interspecific competition— between populations.
-Predation:
•example: lynx vs. snowshoe hare.
-Parasitism:
•example: pine beetle and lodgepole pine.