Estuary Subject Review

Fill-in-the-Blank

An __________ is a partially enclosed body of water and its adjacent habitats where saltwater from the ocean mixes with freshwater from rivers or streams.
Waters whose salt content is between that of freshwater and that of seawater are called __________.
Of the 32 largest cities in the world, 22 are located on __________.

WORD BANK

stenohaline
euryhaline
energy
pneumatophores
propagules
anaerobic
zoea
megalope
anthropogenic
storms
winter ice
anoxic
glaciers
high tides
bar built
barrier
delta
tectonic
smaller
unique
geology
estuary
brackish
estuaries
salinity
variable
tides
two
freshwater

nurseries
pollutants
habitat
fish
ecosystem services
ice age
decreases
lagoons
sediment
earthquakes
fjords
tidal creeks
pannes
mudflats
nutrients
watershed
SWMP
polluted
buffers
coastal elevation
coastal plain
halophytes
smooth cordgrass
mangrove
prop roots
salinity
dense
tidal range
isohalines

highest
mixing
salt wedge
slightly stratified
vertically-mixed
storms
peat
red mangrove
flooded
salinity
wrack
conversion
pollution
biomagnification
sediments
eutrophication
nutrient
pathogens
combined sewage
overflows
invasives
NERRS
increases
dissolved oxygen
photosynthesis
organic matter
pH
isohalines
chlorophyll

In the ocean the concentration of salts, or __________, averages about 35 parts per thousand.
The salinity of estuarine water is __________ from one day to the next.
__________ are a major influence on many estuaries.
Most areas of the earth experience __________ high and low tides each day.
Tides at broad mudflats might appear to be __________ than tides at the end of a long, narrow inlet.
Every estuary is __________.
Estuaries are typically classified based on how saltwater and freshwater mix in the estuary and on their __________.
Estuaries formed by rivers or streams entering massive lakes are called __________ estuaries.
Estuaries are often called __________ of the sea.
Estuaries filter out __________ from rivers and streams before they flow into the oceans.
Estuaries provide critical __________ for many birds, fish, amphibians, insects, and other wildlife.
Estuaries provide habitat for more than 75 percent of the __________ harvested in the United States.
__________ are fundamental life support processes upon which all organisms depend. [two words]
__________ is a spongy matrix of live roots, decomposing organic material, and soil that helps filter pollutants out of the water.
One reason that estuaries are so productive is that the water filtering through them brings in __________ from the surrounding watershed.
The entire land area that drains into a particular body of water, like a lake, river or estuary is called a drainage basin or __________.
Estuaries are some of the most fertile ecosystems on earth, yet they may also be one of the most __________.
Estuaries and their surrounding wetlands act as _______ that stabilize shorelines and protect coastal areas from floods, storm surges, and excessive erosion.
The __________ determines the rate of freshwater that flows into an estuary from rivers and streams. [two words]
__________ estuaries are formed when rising sea levels flood existing river valleys. [two words]
__________ estuaries are characterized by barrier beaches or islands that form parallel to the coastline and separate the estuary from the ocean. [two words]
__________ beaches and islands are formed by the accumu-lation of sand or sediments deposited by ocean waves.
A __________ is characterized by large flat fan-shaped deposits of sediment at the mouth of a river.
__________ estuaries are formed when the earth’s tectonic plates run into or fold-up underneath each other.
__________ are steep-walled river valleys created by advancing glaciers that later became flooded with seawater as the glaciers retreated.
Most coastal plain estuaries in North America were formed at the end of the last __________. [two words]
A protected area of calm water between the coast and a barrier island is called a __________.
Bar-built estuaries and deltas both have large deposits of __________.
The first stage in the formation of a tectonic estuary typically occurs during __________.
__________ tend to have a moderately high input of fresh-water, but very little inflow of seawater.
When a sill prevents deep waters in an estuary from mixing with deep waters of the sea, poor water exchange causes __________ (low oxygen) water to build up on the bottom of the estuary.
Estuaries with a sill are found in areas that were once covered with __________.
__________ create saltwater currents that move seawater into estuaries. [two words]
The daily mixing of freshwater and saltwater in estuaries leads to variable and dynamic chemical conditions, especially __________.
Because freshwater flowing into the estuary is less __________ than water from the ocean, it often floats on top of the heavier seawater.
The difference between the average low tide and the average high tide is the __________. [two words]
__________ are areas in water that have equal salt concentrations.
The shape of the isohalines indicates the amount of __________ that is occurring, and may provide clues about the estuary's geology.
__________ estuaries occur when a rapidly-flowing river discharges into the ocean where tidal currents are weak. [two words]
In __________ estuaries, saltwater and freshwater mix at all depths. [two words]
A __________ estuary occurs when river flow is low and tidally generated currents are moderate to strong. [two words]
Freshwater estuaries are driven by __________.
Salt marshes are a mosaic of snaking channels called __________.
Salt __________ are shallow depressions that contain very high concentrations of salt.
Burrowing organisms such as clams, mussels, oysters, fid-dler crabs, sand shrimp, and blood worms are typical of __________.
Salt marshes are covered with salt-tolerant plants called __________.
__________ is one of the main components of peat and dominates the low marsh all the way up to the estuary’s edge. [two words]
__________ trees grow at tropical and subtropical latitudes, and can grow in anoxic soils where slow moving waters allow fine sediments to accumulate.
Many mangals can be recognized by their dense tangle of __________ that make the trees appear to be standing on stilts above the water. [two words]
The __________ colonizes the seaward side of mangals. [two words]
The zones where white mangrove and buttonwood trees grow are almost never __________.
Plants and animals living in estuaries must be able to respond quickly to drastic changes in __________.
Plants and animals that can tolerate only slight changes in salinity are called __________.
Plants and animals that can tolerate a wide range of salinities are called __________.
It requires a lot of __________ to adapt to constantly changing salinities.
Many species of mangrove trees have aerial roots called __________ that take up oxygen from the air for the roots.
Mangrove seeds that begin growing while still attached to the parent plant are called __________.
During low tides, oysters close up their shells, stop feeding, and switch to __________ respiration.
Blue crab larvae called __________ require water with a salinity over 30 ppt for optimal development.
As they develop, blue crabs eventually return to the estuary as young crabs called __________.
__________ disturbances are caused by humans.
Large __________ are especially destructive to estuaries.
A common natural disturbance to estuaries in non-tropical regions is __________. [two words]
A natural disturbance in salt marshes caused by the burial of vegetation by rafts of dead floating plant material, is called __________.
The greatest human-caused threat to estuaries is their large-scale __________.
__________ is probably the most important threat to water quality in estuaries.
__________ is a process through which toxic substances can accumulate in the tissues of organisms that consume these substances.
Some toxic substances become attached to __________ that flow down rivers and get deposited in estuaries.
__________ is a type of pollution in which excess nutrients stimulate an explosive growth of algae which depletes the water of oxygen when the algae die and are eaten by bacteria.
__________ pollution is the single largest pollution problem affecting coastal waters of the United States.
__________ are disease-causing organisms.
In most estuaries, the largest contributor of bacteria and viruses is probably __________. [three words]
__________ are plants and animals that have found their way into areas outside their normal range.
Non-native species are often introduced to estuaries in the __________ water of ships.
__________ is a partnership program between NOAA and U.S. coastal states that protects more than one million acres of estuarine land and water.
The health of every National Estuary Reserve is continuously monitored by the __________.
As water temperature increases, the amount of oxygen that can dissolve in the water __________.
In estuaries, salinity levels are generally ___________ near the mouth of a river where the ocean water enters.
The amount of oxygen that can dissolve in water _________as salinity decreases.
The amount of __________ in an estuary’s waters is the major factor that determines the type and abundance of organisms that can live there. [two words]
Oxygen enters the water through two natural processes: diffusion from the atmosphere, and __________.
Bacteria, fungi, and other decomposer organisms reduce DO levels in estuaries because they consume oxygen while breaking down __________. [two words]
__________ is related to the amount of sediment and other solids suspended in water.
The chemical components in seawater resist large changes to __________.
Scientists can determine the density of phytoplankton and the amount of primary productivity by measuring ________.

Estuary Subject Review: Crossword Puzzle

Across

6. As water temperature increases, the amount of oxygen that can dissolve in the water __________.

7. During low tides, oysters close up their shells, stop feeding, and switch to __________ respiration.

8. The zone where white mangrove and buttonwood trees grow are almost never __________.

12. Estuaries filter out __________ from rivers and streams before they flow into the oceans.

14. __________ are steep-walled river valleys created by advancing glaciers that later became flooded with seawater as the glaciers retreated.

15. __________ estuaries are characterized by barrier beaches or islands that form parallel to the coastline and separate the estuary from the ocean. [two words]

16. __________ is a partnership program between NOAA and U.S. coastal states that protects more than one million acres of estuarine land and water.

17. Estuaries formed by rivers or streams entering massive lakes are called __________ estuaries.

18. Salt __________ are shallow depressions that contain very high concentrations of salt.

19. __________ are a major influence on many estuaries.

20. Oxygen enters the water through two natural processes: diffusion from the atmosphere, and __________.

22. Of the 32 largest cities in the world, 22 are located on __________.

25. __________ trees grow at tropical and subtropical latitudes, and can grow in anoxic soils where slow moving waters allow fine sediments to accumulate.

26. Burrowing organisms such as clams, mussels, oysters, fiddler crabs, sand shrimp, and blood worms are typical of __________.

28. __________ is dead floating plant material, called that may bury vegetation in salt marshes.

29. The chemical components in seawater resist large changes to __________.

32. The health of every National Estuary Reserve is continuously monitored by the __________.

33. The __________ colonizes the seaward side of mangals. [two words]

34. In the ocean the concentration of salts, or __________, averages about 35 parts per thousand.

38. Estuaries provide critical __________ for many birds, fish, amphibians, insects, and other wildlife.

39. Non-native species are often introduced to estuaries in the __________ of ships.

40. Plants and animals that can tolerate only slight changes in salinity are called __________.

43. Estuaries are often called __________ of the sea.

44. The entire land area that drains into a particular body of water, like a lake, river or estuary is called a drainage basin or __________.

46. Every estuary is __________.

47. Salt marshes are a mosaic of snaking channels called __________.

48. It requires a lot of __________ to adapt to constantly changing salinities.

50. In __________ estuaries, saltwater and freshwater mix at all depths. [two words]

51. As they develop, blue crabs eventually return to the estuary as young crabs called __________.

52. Bacteria, fungi, and other decomposer organisms reduce DO levels in estuaries because they consume oxygen while breaking down __________. [two words]

55. __________ is one of the main components of peat and dominates the low marsh all the way up to the estuary’s edge. [two words]

57. Scientists can determine the density of phytoplankton and the amount of primary productivity by measuring __________.

60. Estuaries are some of the most fertile ecosystems on earth, yet they may also be one of the most __________.

63. Blue crab larvae called __________ require water with a salinity over 30 ppt for optimal development.

64. An __________ is a partially enclosed body of water and its adjacent habitats where saltwater from the ocean mixes with freshwater from rivers or streams.

65. Because freshwater flowing into the estuary is less __________ than water from the ocean, it often floats on top of the heavier seawater.

66. One reason that estuaries are so productive is that the water filtering through them brings in __________ from the surrounding watershed.

67. Tides at broad mudflats might appear to be __________ than tides at the end of a long, narrow inlet.

70. __________ estuaries are formed when rising sea levels flood existing river valleys. [two words]

72. __________ is probably the most important threat to water quality in estuaries.

74. When a sill prevents deep waters in an estuary from mixing with deep waters of the sea, poor water exchange causes __________ (low oxygen) water to build up on the bottom of the estuary.

76. Salt marshes are covered with salt-tolerant plants called __________.

78. __________ is a type of pollution in which excess nutrients stimulate an explosive growth of algae which depletes the water of oxygen when the algae die and are eaten by bacteria.

79. __________ estuaries occur when a rapidly-flowing river discharges into the ocean where tidal currents are weak. [two words]

80. The first stage in the formation of a tectonic estuary typically occurs during __________.

81. Estuaries are typically classified based on how saltwater and freshwater mix in the estuary and on their __________.

82. A common natural disturbance to estuaries in non-tropical regions is __________. [two words]

83. Waters whose salt content is between that of freshwater and that of seawater are called __________.

84. Estuaries provide habitat for more than 75 percent of the __________ harvested in the United States.

Down

1. __________ are plants and animals that have found their way into areas outside their normal range.

2. __________ are areas in water that have equal salt concentrations.

3. Many mangals can be recognized by their dense tangle of __________ that make the trees appear to be standing on stilts above the water. [two words]

4. Mangrove seeds that begin growing while still attached to the parent plant are called __________.

5. Bar-built estuaries and deltas both have large deposits of __________.

9. The salinity of estuarine water is __________ from one day to the next.

10. In most estuaries, the largest contributor of bacteria and viruses is probably __________. [three words]

11. Plants and animals that can tolerate a wide range of salinities are called __________.

13. __________ pollution is the single largest pollution problem effecting coastal waters of the United States.

15. Estuaries and their surrounding wetlands act as __________ that stabilize shorelines and protect coastal areas from floods, storm surges, and excessive erosion.

23. The __________ determines the quantity and rate of freshwater that flows into an estuary from rivers and streams. [two words]

24. Most coastal plain estuaries in North America were formed at the end of the last __________. [two words]

27. __________ is a process through which toxic substances can accumulate in the tissues of organisms that consume these substances.

29. __________ is a spongy matrix of live roots, decomposing organic material, and soil that helps filter pollutants out of the water.

30. __________ are disease-causing organisms.

31. The shape of the isohalines indicates the amount of __________ that is occurring, and may provide clues about the estuary’s geology.

35. The amount of oxygen that can dissolve in water __________ as salinity decreases.

36. __________ is related to the amount of sediment and other solids suspended in water.

37. __________ create saltwater currents that move seawater into estuaries. [two words]

41. Most areas of the earth experience __________ high and low tides each day.

42. A __________ estuary occurs when river flow is low and tidally generated currents are moderate to strong.

45. Freshwater estuaries are driven by __________.

49. __________ substances are chemicals and metals that can causing serious illness or death. They may be poisonous, carcinogenic (cancer-causing) or harmful in other ways to living things. Pesticides, automobile fluids like antifreeze, oil or grease, and metals such as mercury or lead have all been found to pollute estuaries. These substances can enter an estuary through industrial discharges, yard runoff, streets, agricultural lands, and storm drains.

53. __________ beaches and islands are formed by the accumulation of sand or sediments deposited by ocean waves.

54. Estuaries with a sill are found in areas that were once covered with __________.

56. Some toxic substances become attached to __________ that flow down rivers and get deposited in estuaries.

58. Many species of mangrove trees have aerial roots called __________ that take up oxygen from the air for the roots.

59. __________ estuaries are formed when the earth’s tectonic plates run into or fold-up underneath each other.

61. The difference between the average low tide and the average high tide is the __________. [two words]

62. The amount of __________ in an estuary’s waters is the major factor that determines the type and abundance of organisms that can live there. [two words]

68. A protected area of calm water between the coast and a barrier island is called a __________.

69. __________ are fundamental life support processes upon which all organisms depend. [two words]

71. __________ disturbances are caused by humans.

73. A __________ is characterized by large flat fan-shaped deposits of sediment at the mouth of a river.

75. The greatest human-caused threat to estuaries is their large-scale __________.

77. In estuaries, salinity levels are generally ___________ near the mouth of a river where the ocean water enters.

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