Freshwater Marshes

Question 1

Freshwater marshes are characterized by:

Freshwater marshes are the most diverse wetland category

Answer 1

1. Emergent soft-stemmed (herbaceous) aquatic plants. e.g. Arrowhead (Sagittaria), Cattail (Typha), Pickerelweed (Pontederia)
2. Shallow water regime
3. Shallow to nonexistent peat deposits (<30cm peat)
4. Not influenced by tide

Question 2

HYDROLOGY

important characteristics

Answer 2

1. Presence of excess water
   • P > ET
   • Watershed is large enough for adequate runoff or groundwater flow
2. Sources of water
   • Surface water runoff
   • Groundwater
   • Precipitation

Question 3

HYDROLOGY

details

Answer 3

• Seasonal water level fluctuates more than in tidal marshes
• Marshes fed mainly by groundwater will have more stable water levels
• Marshes fed by runoff surface water and precipitation will have more fluctuations in water table
• Marshes fed by a small catchment will have larger water level fluctuations

Question 4

HYDROLOGY

Location of freshwater marshes

Answer 4

• Lacustrine (relating to or associated with lakes)
• Riverine or alluvial
• Palustrine (isolated)

Question 5

BIOGEOCHEMISTRY

Answer 5

• Water and soil chemistry dominated by mineral soils
• Generally minerotrophic
• Water has higher amount of dissolved nutrients than bogs
• Do not have high nutrient loading of tidal marshes

• Microbial activity is high

• Some organic matter
• Circum-neutral pH (6-9)

Question 6

VEGETATION

Answer 6

see slide 20

Question 7

ECOSYSTEM FUNCTIONING

Answer 7

1 productivity ↑

• Underground NPP ↑
(Root: shoot ratio > 1)

Decomposition
•plays an important role in converting leaves to ‘food’ for microbes and invertebrates
•Detritus pathway