BiomesBiome: the major types of terrestrial ecosystems• determined primarily by climate

•2 main factors: __________________________•Depends on _________________; proximity to ocean; and air and ocean circulation patterns

Similar traits of plants & animals for biomes of different parts of world; because of similar climate & evolutionary pressures (_______________________)

Earth’s Major Terrerstrial Biomes

*Wetlands (found all over Earth)

BiomesPrecipitation & temperature are the major factors influencing the distribution of biomes.

Biomes

Fig. 7–13

• _________________have similar effects on general locations of biomes.

• Global air circulation patterns will also affect these biomes (i.e. rainy vs. dry sides of mountains

Desert BiomesCharacteristics:• typically _________________annual precipitation;• sparse, widely spaced, mostly _____ vegetation• Cover ________ of land surface, especially at 30° N and 30° S;• largest deserts on _____________ of continents;• plants either are typically _____ rooted shrubs with _________

leaves, succulants, or short–lived species that flourish after rain;• animals are typically ____________ & have physical adaptations for

conserving water & dealing with heat. Tropical Desert Temperate Desert Polar Desert

Grassland BiomesCharacteristics:

• sufficient rainfall to support grass, but often too ______for forests;• mostly found on ____________ of continents;• maintained by seasonal __________, grazing, & periodic

__________ that prevent invasion by shrubs & trees;• plants include high diversity of grasses & herbaceous plants that

typically have broad distributions & that have ________________ to drought, grazing, & fire;

• animals include large & small herbivores, along with predators adapted to feed on these herbivores.

Forest Biomes• sufficient rainfall to support growth of trees;• Three types:

- tropical, typically ____________evergreen trees with high diversity;- temperate, typically _______________ broadleaf tree with moderate

diversity;- boreal, typical _______________ (needle leaves) with low diversity.

• community of plants & animals typically distributed in layers: - understory of herbaceous plants & shrubs;- Sub-canopy of tree saplings;- canopy of full–grown trees. Note for all

biome categories trend towards _____ rainfall and more ____________ in temperature as latitude increases

Mountain Biomes• diversity of habitat because of diversity

of altitude, slope orientation, corres-ponding _____________________, & soil over short distances;

• complex patterning of vegetation;• make up ________ of Earth's surface;• each _________(300 ft) gain in elevation is

approximately equal to a __________ (62 mi) change in latitude;

• mountain regions contain majority of world's ____________

• ____________: elevation above which trees do not grow;

• ______________: elevation above which there is permanent snow;

• important as ______________ for lowlands.

• Biomes that have _____ productivity have _______ nutrient content in the soil if there is not an influx of nutrients.

• Example: ___________ and the ____________ have poor soil.

• Nutrient ___________________________all affect the amount of available nutrients in an ecosystem.

Soils, Nutrients, and Biomes

• However, ecosystems with very _________ productivity also have a ______ uptake of nutrients.

• So rainforests, which are the most productive ecosystem have very ________ soil due to the rapid uptake of nutrients. (All the nutrients are found in the _____________rather than in the soil.)

• Grasslands have nutrient ______ soil because the have both a good growing season, which has a ______ productivity, and an off-season with _____ decomposition of organic matter which allows for a build-up of nutrients in the soil.

Biome Biomass NutrientAvailability

Explanation

Desert Low Low Inadequate water for living things

Rainforest High Low Rapid nutrient uptake

Wetlands High High Shallow, warm water.

Influx of nutrients from streams.

Grassland Medium High Productive growing season.

Build-up of nutrients during cold and or dry

season (low

Mangroves and Coral Reefs

Mangroves

Coral Reefs

• Both occur in tropical/subtropical waters

• Mangroves: ___________, need sediment-________ water (often occur near river outlets)

• Corals require _______, sediment-free water

• Both require relatively ________ water

• Both ____________ coastlines and provide habitat for ____________species