Aquatic Ecosystems Flashcards Preview

BIO120 > Aquatic Ecosystems > Flashcards

Flashcards in Aquatic Ecosystems Deck (49)
Loading flashcards...
1

salinity

proportion of solutes dissolved in water in natural environments
- often designated in g of solute/kg of water
- cited: parts per thousand

2

turbidity

cloudiness of water caused by sediments and/or microscopic orgs
- determines water c penetration

3

turnovers

(lake ecology) complete mixing of upper & lower layers of water of diff. temps
- occurs each spring & fall in temperate-zone lakes

4

thermocline

steep gradient (cline) in environment temperature, such as occurs in a thermally stratified lake or ocean

5

lake

large enough body of water that water can be mixed by wind & wave action

6

pond

small water source
- smaller than lake

7

littoral zone

shallow water near shore that receives enough sunlight to support photosynthesis
- may be marine or freshwater
- often flowering plants present
- "seashore" zone

8

limnetic zone

open water (not near shore) that receives enough sunlight to support photosynthesis

9

benthic zone

area along bottom of an aquatic environment
- present in most aquatic ecosystems
- nutrient rich (dead decomposing bodies)
- "depth" zone

10

photic zone

(aquatic habitat) water shallow enough to receive some sunlight (whether or not it is enough to support photosynthesis)

11

optic zone

deep water receiving no sunlight

12

plankton

drifting organisms (animals, plants, archaea, or bacteria) in aquatic environments

13

detritus

layer of dead organic matter that accumulates @ ground level or on seafloors & lake bottoms

14

wetland

shallow-water habitats where soil is saturated w/ water for at least part of the year
- presence of "indicator plants," which grow only in saturated soils

15

emergent vegetation

plants (in an aquatic habitat) that extend above the water surface

16

bog

freshwater wetland that has no or almost no water flow, resulting in very low oxygen levels & acidic conditions
- accumulate peat
- low pH 4
- few plants
- plants adapted to high acidic conditions (ie. venus fly trap)

17

marshes

wetland dominated by grasses & other nonwoody plants

WMGN

18

swamp

wetland that has a steady rate of water flow & is dominated by trees & shrubs

WSTS

19

stream

bodies of water that move constantly in one direction
- creek = small stream
- river = large stream
- well-oxygenated b/c of tumbling H2O = mixing

20

estuary

where ocean & river meet
- freshwater & salt water mix
- include: saline marshes & body of water
- most productive environment

21

ocean

continuous body of salt water
- uniform chemical composition

22

interidal zone

region btwn low-tide & high-tide marks on a seashore
- "btwn tide" zone
- nutrient rich

23

neritic zone

shallow marine water beyond interidal zone
- extends down about 200 m, where continental shelf ends
- nutrient rich

24

continental shelf

portion of a geologic plate that extends from a continental under seawater

25

oceanic zone

waters of open ocean beyond continental shelf
- "open ocean" zone
- loses nutrients
- desert zone of the ocean

26

coral reef

large assemblage of colonial marine corals that usually serves as shallow water, sunlit habitat for many other species as well
- rain forests of the ocean

27

physical factors that affect orgs inhabiting aquatic ecosystems

(1) salinity
(2) water depth
(3) water flow & movement
(4) nutrient availability

28

how salinity affects org inhabitation in aquatic ecosystems

(1) affects osmosis
(2) affects water balance in orgs

low S (body) + high S (environment) = water loss

29

how water depth affects org inhabitation in aquatic ecosystems

(1) water absorbs & scatters c
(2) c available mostly on surface of H2O
(3) turbidity determines c penetration

more H2O depth = less c available

30

causes of turbidity

(1) natural - erosion of river sediments by floodwaters & coastal sediment erosion by wave action
(2) human acts - agricultural field run-offs + algal blooms = nutrient pollution