Chapter 49-Biomes Flashcards
Biomes
regions defined by distinct abiotic characteristics and dominant vegetation
Natural Biomes
type of biome present in a terrestrial region depends mostly on climate—temperature, moisture, sunlight, and wind
Temperature
defines the range of species
Moisture
required for life; organisms constantly lose water to evaporation/transpiration
Sunlight
needed for photosynthesis
Wind
exacerbates the effects of temperature and moisture
Anthropogenic (Human) Biomes
> 75% of Earth’s ice-free land is directly altered by H.s.
Examples: farming, logging, and urban development (not including the effects of pollution, invasive species, or climate change)
–Wildlands account for just 11% of terrestrial NPP (Net Primary Production)
–Climate is affected by deforestation and greenhouse gases
Will global climate change affect terrestrial biomes?
YES
-deserts and drought -more evaporation mean more precipation (extreme wet and dry areas)
Simulation studies
models of weather patterns
Observational studies
long-term monitoring
Historical studies
reconstructing prehistorical trends
Experiments
simulate changed climate conditions and to record organisms’ responses
Aquatic Biomes
About 70 percent of Earth’s surface is covered in water
- Salinity
~ concentration of solutes
Affects water balance of organisms (osmosis
- Water depth (and light)
Water absorbs and scatters light
The turbidity/cloudiness
Light →productivity
- Water Flow
The rate of movement:
–Organisms →body shapes and/or behavioural adaptations
–Flow rate can also determine how much oxygen is available to organisms
- Nutrient Availability
In the ocean photic zone, sunlight is abundant, but nutrients are not
When organisms die, they sink to the benthic zone
Organisms in the benthic zone survive by consuming materials from the photic zone
3 types of water flow provide critical nutrients
- Coastal runoff
- Ocean upwelling -bring nutrients to the surface
- Lake turnover- Lakes turn over each spring and fall
