Ch 5 and 6: Climate/Biomes (Terrestrial and Aquatic)

Ch 5 and 6:Climate/Biomes (Terrestrial and

Aquatic)

ClimateWeather:

Climate:

Average temperature and average precipitation are the 2 main factors for climate.

Latitude (distance from equator) and elevation (distance above sea level) also are factors.

ClimateSolar energy and global air circulation

4 factors that determine global air circulations1. uneven heating of the earths surface by the sun

(equator receives more heat then the poles)2. Seasonal changes in temperature and

precipitation.3. Rotation of the earth on its axis (causes the

Coriolis effect – deflects wind to right in northern hemisphere and to the left in the southern hemisphere.

4. Properties of air, water, and land

Climate (Greenhouse Effect)Greenhouse gases:

Greenhouse Effect:

Humans have affected the greenhouse effect by pumping excess CO2 into the atmosphere.

BiomesBiomes:

Ex:DesertGrasslandsChaparralsForestsMountains

DesertsDeserts:

Cover 30% of the Earth’s land and found mostly in tropical and subtropical regions.

Some plant and animal adaptations:Plants drop leaves and become dormant during

dry time. Some plants are succulent. Some have deep roots, some have waxy coating,

Most animals are small, hide during the day, reptiles and insects have thick outer coverings.

Deserts

Grasslands/ChaparralsGrasslands (Prairies):

Tropical grasslands (savannahs)Temperate grasslands (fertile soils)Polar grasslands (tundra)

Exists b/c of seasonal droughts, large herbivores, and fires.

Chaparral:

Grasslands

Forest BiomesForests: areas with moderate to high levels

of annual precipitation. Contains many forms of trees and shrubs.Tropical rain forest: high precipitation with

poor soilTemperate Deciduous Forest: Changes with

seasonsEvergreen Coniferous forest: Cold winters,

wet summer, evergreensTemperate rain forest: coastal areas with

high biodiversity

Forests

Mountain BiomesCovers about ¼ of earths land surface.Dramatic changes in altitude, climate, soil,

and vegetation over a short distance.Many forests are found on mountainsProne to erosion75% of all freshwater is stored as glacial ice

on mountain topsPlay a large role in hydrological cycle.

Human Impact on Terrestrial BiomesHuman activities have damaged or

disturbed more than half of the world’s terrestrial ecosystems.

Humans have had a number of specific harmful effects on the world’s deserts, grasslands, forests, and mountains.

Organisms Live in Aquatic Life Zones

Aquatic systems contain floating, drifting, swimming, bottom-dwelling, and decomposer organisms.Plankton:

Phytoplankton (plant), Zooplankton (animal), Ultraplankton (photosynthetic bacteria)

Nekton: Benthos:Decomposers:

The Coastal Zone: Where Most of the Action Is

The coastal zone: the warm, nutrient-rich, shallow water that extends from the high-tide mark on land to the gently sloping, shallow edge of the continental shelf.

The coastal zone makes up less than 10% of the world’s ocean area but contains 90% of all marine species.Provides numerous ecological and economic

services.Subject to human disturbance.

Estuaries and Coastal Wetlands: Centers of Productivity

Estuaries include river mouths, inlets, bays, sounds, salt marshes in temperate zones and mangrove forests in tropical zones.

Estuaries and coastal marshes provide ecological and economic services.Filter toxic pollutants, excess plant nutrients,

sediments, and other pollutants.Reduce storm damage by absorbing waves and

storing excess water produced by storms and tsunamis.

Provide food, habitats and nursery sites for many aquatic species.

Figure 6-7Figure 6-7

Rocky and Sandy Shores: Living with the Tides

Organisms experiencing daily low and high tides have evolved a number of ways to survive under harsh and changing conditions.Gravitational pull by moon and sun causes tides.Intertidal Zone: area of shoreline between low

and high tides.Organisms in intertidal zone develop

specialized niches to deal with daily changes in:TemperatureSalinityWave action

Barrier Islands

Low, narrow, sandy islands that form offshore from a coastline.

Primary and secondary dunes on gently sloping sandy barrier beaches protect land from erosion by the sea.

Figure 6-10Figure 6-10

Threats to Coral Reefs:Increasing Stresses

Biologically diverse and productive coral reefs are being stressed by human activities.

Figure 6-11Figure 6-11

Biological Zones in the Open Sea:Light Rules

Euphotic zone:

Nutrient levels low, dissolved O2 high, photosynthetic activity.

Bathyal zone:

No photosynthetic activity, zooplankton and fish live there and migrate to euphotic zone to feed at night.

Abyssal zone:

Very cold, little dissolved O2.

Effects of Human Activities on Marine Systems: Red Alert

Human activities are destroying or degrading many ecological and economic services provided by the world’s coastal areas.

Figure 6-13Figure 6-13

FRESHWATER LIFE ZONES

Freshwater life zones include:Standing (lentic)

water:

Flowing (lotic) systems:

such as streams and rivers.

Figure 6-14Figure 6-14

Lakes: Water-Filled DepressionsLakes are large natural bodies of standing

freshwater formed from precipitation, runoff, and groundwater seepage consisting of:Littoral zone:

Limnetic zone:

Profundal zone: Benthic zone:

Effects of Plant Nutrients on Lakes:Too Much of a Good Thing

Plant nutrients from a lake’s environment affect the types and numbers of organisms it can support.Oligotrophic:

Eutrophic:

Freshwater Inland Wetlands: Vital Sponges Inland wetlands act like natural sponges that absorb and

store excess water from storms and provide a variety of wildlife habitats.

Filter and degrade pollutants.Reduce flooding and erosion by absorbing slowly releasing

overflows.Help replenish stream flows during dry periods.Help recharge ground aquifers.Provide economic resources and recreation

Figure 6-18Figure 6-18

Impacts of Human Activities on Freshwater SystemsDams, cities, farmlands, and filled-in wetlands alter and

degrade freshwater habitats.Dams, diversions and canals have fragmented about 40% of

the world’s 237 large rivers.Flood control levees and dikes alter and destroy aquatic

habitats.Cities and farmlands add pollutants and excess plant nutrients

to streams and rivers.Many inland wetlands have been drained or filled for

agriculture or (sub)urban development.