Terrestrial Flora Flashcards
Net primary productivity
amount of biomass produced by a plant, so it’s amount produced in photosynthesis - amount consumed in respiration
annual net primary productivity
amount of biomass fixed by a community of plants
- varies widely depending on ecosystem i.e. very high in tropics, much lower in polar areas
soil respiration
micro-organisms in soil performing cellular respiration on decaying matter
Limiting factors
anything that LIMITS population bc essential for survival
ex: light, moisture, and temperature
Light as limiting factor
photoperiodism - amount of light received in 24 hours, tends to increase as you go higher in latitude
in dense forest, gonna have tall but narrow trees to get sunlight + smaller trees below may die
Moisture
adaptation to moisture excess or deficiency
temperature
fewer plants/animals can survive in cold region
plants have limited cold tolerance bc theyre ALWAYS exposed to cold, can’t seek shelter like animals
wind
in places w. extreme wind –> wind causes excessive drying bc of increased evaporation
wildfires
can be useful in clearing away dead vegetation for new plants + animals to come
sometimes needed for plants to germinate
Biome
collection of plants
and animals over a large area that have broadly similar adaptations and relationships with the environment and climate
10 major biomes
- Tropical rainforest
- Tropical deciduous forest
- Tropical scrub
- Tropical savanna
- Desert
- Mediterranean woodland and shrub
- Midlatitude grassland
- Midlatitude deciduous forest
- Boreal forest
- Tundra
ecotone
transition zones of competition between biozones
xerophytes
plants that are built to withstand extremely dry conditions
examples:
-taproots = very deep thin roots to get water
-stems = spongy structures that store moisture
-hard, waxy leaves to inhibit evaporation
-can lie dormant for years till rain comes
hydrophytic adaptations
plants suited for wet terrestrial environments
hydrophyte = in water, hygrophyte = moisture loving
many have extensive root systems to anchor to ground, while some that grow in standing/moving water have weak/pliable stems that withstand current
Vertical zonation
significant changes in elevation over short distance –> cause diff plant to exist in relatively narrow zones
due to effects of temperature + precip
tree line
elevation above which trees cannot survive
Biome: Tropical rainforest
HIGH RAINFALL HIGH TEMPS
Climate: Af
1) greatest biodiversity
2) tall, broadleaf evergreens
3) layered structure (tallest trees - emergents, 2nd layer that provides shade, erratic 3rd layer)
4) Lots of available nutrients + stuff decomposes very quickly + majority of food in canopy
5) Limiting factors = none* (but canopy system means plants at bottom don’t get much light)
6) NPP = HIGH
Biome: Tropical Deciduous Forest
Found in transition btwn Af + Aw climates
1) High temperatures BUT lesser (seasonal) rainfall than tropical rainforest
2) Less dense canopy –> lesser rain
3) More light reaches ground –> many trees shed leaves at same time in response to lack of rain
4) Less tree diversity, more shrubs/smaller plant diversity
5) Limiting factor = water
6) NPP = High to moderate
Biome: Tropical Scrub
Found in Aw climate + BSh climate
1) dominated by low-growing, scraggly trees
2) lesser diversity
3) mainly evergreen in wetter portions of scrub, everywhere else it’s decidious
4) many ground-dwelling mammals, reptiles, birds, insects
5) Limiting factor = water
Biome: Tropical Savanna
Located in ITCZ area (doesn’t fully overlap with Aw climate)
1) dominated by tall grasses + park savanna (scattering of trees)
2) vegetation altered by humans –> many biomes (trop. decidious, scrub) converted into savanna
3) pronounced seasons –> wet seasons –> tall green grass, dry season –> dead, brown, wildfire season
4) big game animals –> lions, giraffes, zebras
Biome: Desert
midlatitude locations of Eurasia, NA, SA
closely correleated with BWh (subtrop. desert) and BWk (midlatitude desert) climates
1) variable vegetation –> mainly zerophytic plants
2) limited variety of large mammals –> appearance of stillness
3) IF is heavy rain –> transform desert, triggering germination of dormant wildflowers
4) limiting factor - water
Biome: Mediterranean Woodland + Shrub
Found in midlatitudes in Cs climates
1) dominated by chapparal + grassy woodland + flowering plants
2) chapparal = small hard leaves to prevent moisture loss
3) mainly broadleaf evergreens + deep roots
4) rainless summers + summer fires –> plants adapted to rapid recovery
5) limiting factor = water
6) Climate = Cs (30-45 degree latitude)
7) NPP = medium
Biome: Midlatitude Grassland
Occurs in midlatitude climates (BSh BSk)
1) tall grasses in wetter regions –> called praries, shorter grasses in dry region –> steppe
2) most plants perennials
3) fires common –> lack of shrubs
4) animals like bison BUT humans took over much of prarie
5) limiting factor = water
Biome: Midlatitude Deciduous Forest
Located in Northern hemisphere
1) mainly broadleaf, deciduous trees
2) majority of it cleared for agriculture + human use
3) Full canopy in summer, beautiful fall colors winter
4) huge variety of plants, birds, animals
5) Climate = C
6) Limiting = Temperature, Light
7) NPP = medium to high
Biome: Boreal Forest (Taiga)
Northern North America + Eurasia, follows subartic
1) simple assemblage plants –> mainly needleleaf conifers
2) trees taller + more densely populated in southern part of taiga –> longer summers there
3) deciduous shrubs common
4) bogs + swamps common –> caused by poor drainage bc of permafrost
5) Limiting factor - Temperature, light
6) Climate - D
Biome: Tundra
Northern edge of Northern hemisphere, closely correlated w. Tundra (ET) climate
1) cold, arid grassland w. short, cool summers + limited moisture
2) many dwarf plants –> arranged in dense, ground-hugging arrangement (grasses, mosses, shrubs, lichens)
3) summer - water logging bc of permafrost
4) lots of birds + insects in summer
5) Limiting factor - temperature, light, water (bc of polar high)
6) NPP = low
Forest vs woodland
forest = trees more densely together –> produces canopy
woodland = trees more spread apart
as water becomes limiting what happens
forest, woodlands, scrubs, grasslands, deserts
**first to go are large trees, then scrubs, then grasses*
