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Flashcards in Final Deck (39):
1

What are three issues impacting the tropical forest in Costa Rica?

- Cattle grazing
- Logging
- Cash crops in forest

2

What are three characteristics of tropical forests?

- Diversity & coevolution
- Seasonality of system is determined by rainfall
- Highly weathered soils

3

What are four take-home points of tropical forest restoration?

- Many factors may limit recovery
- Lack of seeds is important
- Competition is important
- Speed of recovery is site-specific

4

What are four strategies for tropical forest restoration?

- Assisted natural regeneration
- Remove disturbance
- Attract fauna
- Plant native tree species

5

What are five types of wetlands?

- Coastal wetlands
- Mangroves
- Freshwater marshes
- Forested freshwater wetlands
- Bogs/peatlands

6

What are three types of freshwater marsh?

- Tidal marsh: near the coast, mix of freshwater, brackish, and salty
- Prairie potholes: glacial depressions
- Vernal pools: seasonally-flooded glacial depressions

7

What are three factors that delineate wetlands?

- Wetlands are transitional ecosystems with species adapted along a gradient of abiotic conditions
- Very complicated soil chemistry due to hydrology
- Vegetation adapted to flooded and low oxygen conditions

8

What are three variable factors of wetland hydrology?

- Duration
- Periodicity
- Depth

9

What are three variable factors of soil chemistry in wetlands?

- Lack oxygen
- High organic matter: mineral is <20% organic matter; organic soil is >20% organic matter
- “Oxidized rhizosphere”: looks red along roots

10

What are three reasons why wetlands are important?

- Erosion buffer
- Flood buffer
- Sediment stabilization

11

What re four stresses to wetlands?

- Physical (filling, draining, flooding)
- Climate change (sea level rise)
- Chemicals (nutrients/toxics)
- Biological (grazing, invasives)

12

What are three restoration strategies for wetlands?

- Hydrology (topography, flood regime, dechannelization)
- Reduce contaminants/nutrients (source reduction, dredging)
- Revegetate (seeding, inoculation, sods)

13

How much of the San Francisco tidal wetlands have been destroyed?

80%

14

What are four major 1970's environmental policies that protect the San Francisco tidal wetlands?

- Clean Water Act (1972)
- Coastal Zone Management Act (1972)
- Endangered Species Act (1973)
- Clean Water Act 404 Permits (mitigation)

15

What is a culvert?

A drain or waterway below a road

16

What is a levee?

Embankment built along a river

17

What is sinuosity?

Channel length / valley length
"S" shape

18

What is a checkdam?

A dam designed to back up or divert water

19

What are three characteristics of rivers?

- Openness
- Dynamism
- Patchiness/heterogeneity

20

What does it mean to channelize a river?

- Straighten
- Increase velocity and rate of flow
- Decrease base flow

21

What are three restoration strategies for a channelized river?

- Reestablish connection with floodplain
- Restore river morphology and habitat diversity
- In-stream structures (checkdams, logs, boulders, woody debris)

22

What are three restoration strategies for river water quality and erosion?

- Reduce chemical, nutrient, and sediment inputs
- Wetlands and buffer strips
- Improve land management practices

23

Epilimnoin

The upper, oxygen-rich layer of a lake

24

Metalimnion

Middle layer of a lake - changes in temp and salt

25

Hypolimnion

The cold, oxygen-poor, bottom later of a lake

26

Oligotrophic

Low nutrient, clear lake

27

Mesotrophic

"Intermediate" nutrient lake

28

Eutrophic

High nutrient lake

29

What are six stresses to lakes?

- Eutrophication
- Sedimentation
- Water diversion
- Acidification
- Toxic substances
- Exotic species

30

What are three restoration methods for lakes?

- Prevent the problem from happening
- Treat waste
- Riparian zone management / wetland creation

31

What in-lake material can be used to reduce phosphorus?

Alum

32

What is the process of dredging up the bottom of a lake to aerate it, then replacing it?

Hypolimnetic aeration

33

What are four methods to remove toxic substances in lakes?

- Remove at the source
- Remove through sediment
- Plant harvesting
- Bioremediation

34

What are four lake restoration methods that don't stop the problem at the source?

- In-lake methods for removing nutrients
- Sediment skimming
- Deep water discharge
- Hypolimnetic aeration

35

What are five marine restoration strategies?

- Marine reserves
- Improved fisheries practices
- Bioremediation
- Animal translocation/reintroduction
- Kelp forest & seagrass restoration

36

What are four stresses on coral reefs?

- Sedimentation
- Boats / human activity
- Dynamite/cyanide fishing
- Ocean acidification

37

What is monitoring?

Systematic and orderly gathering of specific data over a period of time, in order to make sure that certain conditions are achieved

38

What is surveillance monitoring?

Identifying problems early on in a project

39

What are SMART goals?

Specific
Measurable
Attainable
Relevant
Time-bound