Ecosystems

Question 1

Swamp, marshes and shallow open waters characteristics

Answer 1

Generally nutrient-rich, productive sites
Water pH is usually near neutral
High organic matter content in soil, but well decomposed
Water levels tend to vary seasonally and across years
Oxygen deprivation not serious problem

Question 2

What determines type of wetlands?

Answer 2

Drainage pattern, salt/freshwater, amount of oxygen, type of dominant vegetation

Question 3

Characteristics marshes

Answer 3

wetlands that are periodically inundated by standing or slow-moving water and hence are rich in nutrients
Marshes are wet, mineral-soil areas, well-decomposed OM is present. They are characterized by an emergent vegetation of reeds, rushes or sedges, with few woody plants, and the subsurface is continuously waterlogged; standing water may or may not be present.

Question 4

Characteristics of swamps

Answer 4

wetlands where standing or gently moving waters occur seasonally or persist for long periods, leaving the subsurface continuously waterlogged. The vegetation is dominated by forest or tall shrubs. Standing water may or may not be present.

Question 5

Characteristics of floodplain forest

Answer 5

Forests located next to rivers or lakes that are flooded only seasonally, in our region in the spring and possibly the fall, they have a somewhat open canopy, & may meet the criteria of swamp, or could be drier, depending on soil texture and topography; often have high silt content in soil; subsurface may or may not always be inundated, so floodplains are not necessarily swamps

Question 6

Shallow open water

Answer 6

The surface waters are ~75% free of emergent vegetation, but floating, rooted, aquatic plants may be present.
The depth of water is usually less than 2 m at midsummer levels. Could vary seasonally. Most of the year has water covering the soil.
Includes: lake and river edges & ponds [étangs] relatively small, non-fluvial bodies of standing water representing a transitional stage between lakes and marshes.

Question 7

Common marsh plants, families and genera

Answer 7

Salix, Sagittaria, Typha, Iris, Phragmites Australis, Potamogeton, Lythrum Salicaria, Poaceae, Nymphaeaceae

Question 8

Common plants in salt marshes

Answer 8

Salt tolerance is a fairly rare trait in plants
- Poaceae
- Cyperaceae
- Juncaceae

Question 9

Why did Europe lose more species during the de-glaciation than NA?

Answer 9

Alps blocked species from moving south

Question 10

Forests are an important ecosystem type in which biomes in Canada?

Answer 10

Boreal
Temperate

Question 11

What are the 3 biomes in Quebec?

Answer 11

Arctic Tundra
Boreal Forest
Temperate Forest

Question 12

What gives the name to the different bioclimatic domains?

Answer 12

The main tree species

Question 13

What are the layers in a forest

Answer 13

1. Overstory (Canopy)
2. Subcanopy
3. Understory / Shrub layer
4. Ground vegetation / herb layer

Question 14

What are the main tree species in the NA Boreal Forest

Answer 14

Coniferous
- Larix Laricina
- Picea Mariana
- Picea Glauca
- Abies Balsamifera
- Pinus Banksiana

Deciduous
- Populus Balsamifera
- P. Tremuloides
- Betula
- Acer

Western Boreal Forest, southern edges transition into aspen parklands and open praires

Question 15

Environmental conditions in the boreal forest

Answer 15

• Sunlight consistent in the growing season (not as strong phenological-related changes in understory light, since canopy of evergreen species is always present)
• Colder overall
  ( Minimum and average temperatures
  Growing season length shorter
  Later spring and earlier fall frost dates)
• Decomposition rates slow
  (Due to cold, Low nutrient content foliage,
  Decomposition-resistant foliage)

Question 16

Characteristics of the Canadian Shield

Answer 16

Large, exposed craton (very old rock)
- Soils: young due to recent glaciation, most sites have thick humus layers because of slow decomposition
- Bedrock/soil parent material is resistant to breakdown—leads to acidic soil with thick humus layer

Question 17

Plant adaptations on the Canadian shield

Answer 17

• Tree shapes help shed snow, reduce chance of branch breakage
• Evergreen leaves take advantage of full growing season
• Tissues have very good dormancy, cold adaptations
  Understory plants often sub-shrubs, evergreen or semi-evergreen
• Ericaceae family plants common, also many bryophytes and lichens
  Understory plants protected by extreme cold from snow cover

Question 18

What characterizes a desert

Answer 18

• Low precipitation: less than 250 mm a year
• Potential evapotranspiration exceeds precipitation
• Can occur at different average annual temp and precipitation levels
• In NA, several mountain ranges/isolated mountains

Question 19

Where is precipitation very low globally

Answer 19

• At equator: high sun intensity causes evaporation and a moist warm air to rise and release moisture in the tropics
• Around 30 N or S, cool dry air falls causing bands of deserts

Question 20

Other challenging environmental conditions of deserts

Answer 20

Large fluctuations in day/night temperatures because few clouds to capture reflected infrared radiation, so no sun, no heat

Exposed soils (because of incomplete cover of vegetation) lead to high rates of weathering and erosion (since more sun exposure, more temperature fluctuations, exposure to wind) and very low organic matter content

Some deserts have salt concentrated at the surface because of evaporation from the soil bringing salts to the surface and not enough heavy rains to leach the salts out of the soil

Question 21

Desert: plant interactions and adaptations

Answer 21

Mutualistic/facilitation types of exchange are important/ more frequent than in more productive environments for plant growth

Competition for resources still occurs, but the harsh growing conditions mean that being close to a neighbour might be more of an aid than a hinderance

Main positive exchanges: protection from herbivores, microhabitat of shade, wind blocking, and hydraulic lift from deeper rooted neighbours

Question 22

4 of the bigger named deserts in NA

Answer 22

Great Basin
Mojave
Sonoran
Chihuahuan

Question 23

Sonoran Desert Families (highest count to lowest count)

Answer 23

Asteraceae
Fabaceae
Poaceae
Cactaceae
Malvaceae

Question 24

Great Basin desert: which plants dominate?

Answer 24

Northern, shrubby woody plants, less diverse than other desert regions
Sagebrush (asteraceae) dominant species - deep roots bring water to the surface

Question 25

Basin and Range of Great Basin Desert

Answer 25

Ancient lake basins framed by mountain ranges. Basins dominated by woodlands at mid-elevations, sparse grasslands at lower elevations to desert scrub.

Question 26

Playa of Great Basin Desert

Answer 26

During the last glaciation, these basins were flooded, but as the climate dried, the lowest part of the basin became a dry, salty deposit where few plants can grow.

Question 27

Sonoran Desert Characteristics

Answer 27

High diversity Habitats vary greatly with topography Indicator species: Saguaro cactus, Carnegiea gigantea Cactaceae Mesquite Spring habitats harbor remnants of the flora that prospered when the region was wetter during and after the last glaciation; rivers and streams are also present

Question 28

Lower Bajada of the Sonoran Desert Common Species

Answer 28

Fabaceae trees

Question 29

Stream of Sonoran Desert

Answer 29

Asteraceae Salicaceae Papaveraceae

Question 30

Mojave Desert

Answer 30

A transitional desert at fairly high elevations, parts with a good water supply, but also Death Valley! Joshua tree is the indicator species for this desert. Several cactaceae endemic to Mojave

Question 31

Chihuahuan Desert

Answer 31

High-elevation (mostly 1000-1700m) warm desert in Texas, New Mexico and Mexico Limestone and calcareous soils common Rich diversity of Cactaceae and Asparagaceae: Agavoideae subfamily Indicator species: Agave Lechuguilla

Question 32

Definition of a peatland

Answer 32

Wetlands underlain by partially decomposed or undecomposed organic matter, usually derived, at least in part, from Sphagnum mosses to a depth of at least 12 inches Nutrient availability is low

Question 33

How are Sphagnum mosses related to peatlands?

Answer 33

Sphagnum mosses create this habitat over time where conditions permit by reducing the pH of the bog water and generally limits decay of organic matter from the action of microbes

Question 34

What are the varieties of Peatlands?

Answer 34

Bogs: Ombotrophic (fed from clouds). Minerals coming only from rain or snow Fens: Minerotrophic (fed from minerals in earth). Precipitation + ground water from elsewhere

Question 35

Where are peatlands found?

Answer 35

Peatlands are generally found in cool, wet climates, with relatively short growing seasons, but can also occur in the tropics

Question 36

How does sphagnum moss lowers the pH and limit decay?

Answer 36

hold large quantity of water, which leads to anoxic environment-low O2 limits plants in low areas more produce sites of cation exchange on surface; will give off H+ ions but absorb Ca 2+ and other base cations produce phenolic compounds, which bind nitrogen in the dead bodies of vascular plants, animals, etc. produce anti-microbial compounds Result: peat accumulation—some species form mounds, some are in flat, wet depressions & other plant growth very limited Leading to open, moist habitats ideal for Sphagnum

Question 37

What are the main kinds of adaptations for nutrient acquisition in peatlands?

Answer 37

- Cyperaceae have deep roots that can access the mineral soil to acquire some of its nutrients - Thick, waxy evergreen leaves to retain nutrients for longer, maintain leaves over winter and increased mechanical strength

Question 38

Plants found in peatlands

Answer 38

Trees: - Thuja Occidentalis - Picea Mariana - Larix Laricina - Acer Rubrum - Betula Populifollia Carnivorous plants - Sarraceniaceae - Droseraceae Ericaceous Shrubs Orchids Nymphaceae

Question 39

Tundra definition

Answer 39

BIome where it is too cold for trees to survive Average temp of warmest month: < 10 C One month has ave. temp > 0 C

Question 40

Important climatic factors for plant life in arctic tundra

Answer 40

Low precipitation, but also low evapotranspiration Very cold temperatures in winter and cool to warm temperatures in summer; strong winds If average annual temperature less than -2 °C:

Question 41

Topography impacted due to cold:

Answer 41

Freezing and thawing, lack of water infiltration leads to unique patterns of shallow lakes and vegetated hills with ice cores (pingos) Pingos: : small mountains formed from ice under the soil layer

Question 42

What are the unique land formations that differential time of spring thawing leads to?

Answer 42

Rivers flow north, so upstream areas thaw before downstream areas. Result: ice dams and diversion of flow

Question 43

Biogeography of tundra

Answer 43

- Most species-poor in terms of NA flora. - Relatively young in terms of evolution - First significant amount of tundra ~ 3 Million years ago

Question 44

What are the 3 main ecosystems in the tundra biome?

Answer 44

1. Mires: general term for arctic wetlands, peat forming and underlain by permafrost 2. Tundra (also the name of the biome): vegetation dominated by graminoid species, or erect or prostrate shrubs, underlain by permafrost 3. Barrens: areas with very sparse vegetation. On mountain sides, extremely cold and windy locations, other rocky areas

Question 45

What are the main stressors of tundra plants and their adaptations?

Answer 45

Stresses: cold, desiccation (drying out), low nutrient availability, very short growing season, lower insect pollinator diversity (no bees, for example) Adaptations: - short (protection by snow) - evergreen leaves - perennial - cushion growth form common - vegetative reproduction is importantL asexual seed production, selfing, very common

Question 46

Important arctic families of plants

Answer 46

Salicaceae Polygonaceae Saxifragaceae Caryophyllaceae Fabaceae Rosaceae Asteraceae Poaceae Brassicaceae

Question 47

Which family is especially important in shrub-tundra?

Answer 47

Salicaceae

Question 48

What family is especially important in mires and herb tundra?

Answer 48

Cyperaceae

Question 49

What is an important impact of climate change in Quebec's tundra

Answer 49

Isotherm displacement Isotherms indicate regions that share the same annual mean temperature. Discontinuous permafrost line has already moved 130 km N in Quebec It is projected that for much of the boreal and tundra biomes there will be a reduction in snowfall; Wildfires projected to become more frequent

Question 50

What family dominates grasslands?

Answer 50

Poaceae

Question 51

Grasslands

Answer 51

Could have a cold season, different dry seasons/wet seasons Precipitation is not adequate for the development of forests with closed canopies * natural disturbances important : Fire, grazing animals Variation in topography at a small scale, and climate at a large scale, gives a great variation in plant communities

Question 52

Natural disturbances of the NA prairies

Answer 52

Mix of frequencies maximized species diversity - Bison wallows used continuously over many years, hence providing a high frequency disturbance regime that favors annual plants adapted for colonization of disturbed areas - Fires are less frequent (typically 3-5 years) but spread over wide areas, influencing regional diversity patterns.

Question 53

Diversity of grass growth patterns in grasslands

Answer 53

Bunch grasses (not spreading by rhizomes or stolons) VS Sod-forming-spreads and makes sod __________________________ Cool-season grasses (C3 photosynthesis; active growth in spring and/or fall) VS Warm season grasses (C4 photosynthesis, active growth in summer)

Question 54

Why does fire favour herbaceous plants over trees and shrubs?

Answer 54

1: location of growing points * 2: amount of biomass removed by burning * 3. length of time to regain reproductive maturity

Question 55

Why is growth more difficult towards the west

Answer 55

Less rooting depth and less precipitation

Question 56

What are the types of grassland ecosystems in Canada?

Answer 56

* Aspen parkland—a grassland with open areas, and areas of fairly dense Populus trees—transitional between the boreal forest and the prairie on the north edge * Oak savanna—grassland with some trees transitional between temperate forest and tall grass prairie this is on the east side of the tallgrass prairie * tallgrass prairie—more precipitation—to the east * shortgrass prairie—less precipitation—to the west Prairie potholes—within the different grassland regions, these are shallow wetlands very important to waterfowl

Question 57

Grassland floras

Answer 57

Asteraceae Fabaceae Cyperaceae

Question 58

Plant adaptation in grasslands

Answer 58

Species have differet times of active growth: benefit is less competition

Question 59

What is commonly referred to as the "duck factory"

Answer 59

The prairie potholes created by past glacial melt and that is fed by snowmelt as it is not drained by surface flows It is 10% of breeding grounds, but produce over 50% of NA wetland birds!

Question 60

Why are rare species protected by law?

Answer 60

Standard definitions are needed so that laws relate to consistent levels of threat for species extinction within each legal jurisdiction. * For conservation to be harmonized across the globe for each threatened species as much as is possible. * For the application of international laws on the trade and movement of listed rare species (CITES-the Convention on International Trade in Endangered Species of Wild Fauna and Flora)

Question 61

What are the 3 categories defining a rare species?

Answer 61

Rarity Threats Trends

Question 62

Who keeps track of rare species in Quebec?

Answer 62

Centre de Données sur le Patrimoine Naturel du Quebec (CDPNQ)

Question 63

What do they mean by rare species?

Answer 63

In a context of conservation, we are concerned with declines in the population of species, such that they are predicted to disappear (become extirpated or extinct) in the near future. * Usually, this is linked to both natural rarity causes, and impacts on the species from direct or indirect human pressures -namely habitat loss and degradation, and introduced species, including diseases

Question 64

What are the natural causes of rarity?

Answer 64

1) naturally small population sizes 2) uncommon habitats 3) restricted geographic distributions combinations of these three….give seven forms of rarity, and commonness

Question 64

What is the main threat for species in Qc?

Answer 64

Habitat loss

Question 65

Why does a species that is locally rare but common in other area could be protected?

Answer 65

Conservation status of species is often defined at the level of country, not planet * If a species is rare in your country, often it is protected– Even if it is more common elsewhere

Question 66

What is serpentine?

Answer 66

A name used to refer to rocks that are: * Highly basic * Rich in magnesium silicate and iron * May be high in other trace metals too