APES Test 2 Biomes

Question 1

streams and rivers

Answer 1

freshwater, <1% salt concentration
Flowing (lotic) water
“Riparian” habitats- area adjacent to river or stream
Fast moving water= high oxygen content—supports trout
Slow moving = inc. in sediments and nutrients
deliver nutrients to ecosystems

Threats:
Diversion
Dams
Channeling

Question 2

lakes and ponds

Answer 2

freshwater, <1% salt concentration
Standing (lentic) bodies of water enclosed by land
Spring and fall overturn
May be described as
Oligotrophic
Mesotrophic
Eutrophic

Threats
pollution

Question 3

wetlands

Answer 3

Freshwater
<1% Salt concentration
Lowland areas saturated where soils are saturated with water at least part of the time of a year.
Marshes- wetlands with emergent grasses
Swamps- wetlands with emergent woody vegetation
Bogs – wetlands rich in decomposing plant material- acidic soils, mosses
Essential Ecosystem services- flood control, water filtration and purification

Threats:
Drained for agriculture and development

Question 4

Estuaries

Answer 4

Fresh water meets salt water, Variable salinity
Highly productive due to high nutrient content
Area essential for fish nurseries, bird nesting/ reproduction
Ecosystem services- filter pollutants
Mangrove forests- decrease erosion and provide habitats for marine organisms

Threats: Drained for agriculture and development

Question 5

Coastal/ Intertidal

Answer 5

Marine
~3% salt concentration
Communities subjected to daily variation in water levels, temperature and sunlight
Animal adaptations to with stand mechanical force of waves
Areas exposed to alternately to air during low tide and high tide

Threat: Destroyed by pollution and human activity

Question 6

Coral Reef

Answer 6

Marine
~3% salt concentration
Symbiotic relationship between corals and algae
Shallow region- light penetrates- high photosynthesis
High biodiversity

Threat: Sediment pollution blocks sunlight, lower pH, warmer temperatures= coral bleaching
High nutrient load from runoff allows algae to outcompete coral

Question 7

Open Ocean

Answer 7

Marine
~3% salt concentration
Waters constantly mixed by currents
Plankton live in photic zone
Includes benthic and abyssal zones with no light, and little nutrients
Large free swimming organisms
also called pelagic region

Threat:
Plastic pollution in the gyres

Question 8

2 primary abiotic factors have major impacts on the kinds of climax communities that develop in any part of the world:

Answer 8

Temperature
Patterns of precipitation.

Question 9

The distribution of terrestrial ecosystems is primarily related to precipitation and temperature.

Answer 9

Temperature is warmest near the equator and cooler toward the poles.
As altitude increases, average temperature decreases.
Moving from sea level to mountain tops, it is possible to pass through a series of biomes similar to what would be encountered moving from the equator to the North Pole

Question 10

Desert

Answer 10

Deserts are areas that average less than 25 cm annual precipitation.
Unevenly distributed throughout the year.
They are likely to be windy.
They experience large daily temperature fluctuations.
There is infrequent cloud cover.
There are many species, but they are present in low numbers.
Many species exhibit specialized adaptations to climate, such as the ability to conserve water.

Human impact on deserts:
Humans have historically had little impact on deserts.
Modern technology allows for the transport of water to the desert.
This has resulted in the development of cities in some desert areas and some limited agriculture as a result of irrigation.

Question 11

Grassland

Answer 11

Temperate grasslands, also known as prairies or steppes, are widely distributed over temperate parts of the world.
They typically receive 25 -75 cm of annual precipitation.
Fire is an important force in preventing the invasion of trees and releasing nutrients from dead plants to the soil.
The primary consumers are large herds of migratory grazing mammals. Many insect species are also common.
Human impact on grassland:
Most of the moist grasslands of the world have been converted to agriculture.
Most of the drier grasslands have been converted to the raising of domesticated grazers like sheep, cattle, and goats.
Little undisturbed grassland is left, and those fragments that remain need to be preserved as refuges for the grassland species that once occupied huge portions of the globe.

Question 12

Savanna

Answer 12

Savannas are found in tropical parts of Africa, South America, and Australia.
They are characterized by extensive grasslands spotted with occasional patches of trees.
They receive 50-150 cm annual precipitation, unevenly distributed throughout year.
Rainfall patterns produce a seasonally structured ecosystem.
Fire is a common feature.
Many trees are involved in nitrogen fixation.
Human impact:
Savannas have been heavily impacted by agriculture.
Because of long periods of drought, raising crops is difficult without irrigation.
Some areas support nomadic herding.
In Africa, there are extensive areas set aside as parks and natural areas and ecotourism is an important source of income.

Question 13

Mediterranean Shrublands (Chaparral)

Answer 13

(low precip, seasonal temp)
Mediterranean shrublands are located near oceans and are dominated by shrubby plants.
Their climate features wet, cool winters and hot, dry summers.
They receive 40-100 cm annual precipitation.
This biome is typical of the Mediterranean coast, coastal southern California, as well as parts of Africa, Chile, and Australia.
Vegetation is dominated by woody shrubs adapted to hot, dry summers.
Fire is a common feature.
Human impact:
Very little undisturbed Mediterranean shrubland still exists.
Agriculture is common, often with the aid of irrigation.
Major cities are located in this biome.

Question 14

Tropical Dry Forest

Answer 14

The tropical dry forest is another biome heavily influenced by seasonal rainfall. These biomes are found in Central and South America, Australia, Africa, and Asia.
Annual precipitation ranges 50-200cm.
Many exhibit a monsoon climate with highly seasonal rainfall.
Plants have developed special adaptations to survive drought.
Human impact:
Many of these forests occur in areas of very high human population.
Harvesting of wood for fuel and building materials has heavily affected these forests.
Many of the forests have been converted to farming or the grazing of animals.

Question 15

Tropical Rainforest

Answer 15

(low precipitation, high temp)
Tropical rainforests are located near the equator where temperature is relatively warm and constant.
Most areas receive 200+ cm annual rainfall, and some receive in excess of 500 cm.
The soil allows high levels of leaching, thus most nutrients are tied up in biomass.
Tropical rainforests have a multi-layered canopy.
Epiphytic plants
They also host a very high diversity of species.
Human impact
Tropical rainforests are under intense pressure from logging and agriculture.
Many of the countries where tropical rainforests occur are poor and seek to obtain jobs and money by exploiting this resource.
Forestry can be a sustainable activity, but in many cases it is not.

Question 16

Temperate Deciduous Forest

Answer 16

(high precipitation, seasonal temp)
Temperate deciduous forests are typical of the eastern half of the United States, south-central and southeastern Canada, southern Africa, and many parts of Europe and Asia.
These areas receive 75-100 cm annual precipitation, evenly distributed throughout the year.
Trees typically lose their leaves during the winter and replace them the following spring.
This biome features mild winters and a long growing season (6 months).
In contrast to tropical rainforests, where individuals of a tree species are scattered throughout the forest, temperate deciduous forests have many fewer species; some may have two or three dominant tree species.
Human impact:
Most of the temperate deciduous forests have been heavily affected by human activity.
Much has been cleared for farming.
Much of the current forest is subjected to periodic logging.
Major populations centers of eastern North America and Europe are in areas that were originally temperate deciduous forest.

Question 17

Taiga, Northern Coniferous Forest,
or Boreal Forest

Answer 17

(Seasonal precipitation, seasonal temp)
Throughout the southern half of Canada, parts of northern Europe, and much of Russia, there is an evergreen coniferous forest known as the taiga, northern coniferous forest, or boreal forest.
This biome receives 25-100 cm precipitation annually.
It features short, cool summers and long winters with abundant snowfall.
The climate is humid because of the great deal of spring snowmelt; low temperatures reduce evaporation.
The trees are adapted to winter conditions:
Needle-shaped leaves prevent water loss.
Flexible branches

Human impact:
Human impact is less severe than with many other biomes because population density is low.
Logging is common.
Herding of reindeer occurs in northern Scandinavia.

Question 18

Tundra

Answer 18

North of the taiga is the tundra, an extremely cold region that lacks trees and has a permanently frozen subsurface soil.
The permanently frozen soil layer is called permafrost.
The tundra receives less than 25 cm annual precipitation.
This biome has a short, wet summer.
Waterlogged soils and shallow ponds and pools are present in spring and summer.
Plants are usually less than 20 cm tall.
Tundralike communities known as alpine tundra are found on mountaintops throughout the world.

Human impact:
Few people live in this region.
Local native people often rely on subsistence hunting for food.
Because of the very short growing season, damage to this kind of ecosystem is slow to heal, so the land must be handled with great care.

Question 19

benthos

Answer 19

Bottom portion of the ocean

Question 20

Upwellings

Answer 20

Upward flows of ocean water

Question 21

Human Disturbance overall

Answer 21

Temperate forests - logging and habitation
Shrubland/Chaparral - habitation and favorable climate
Temperate grassland - agriculture
Tundra - harsh climate and poor soils, not alot of cities and habitation, but do mine or drill there
Taiga - loggings, tar sands, and natural gas (mining and drilling)
Tropical rain forests - some more dense and hard to explore so remain mostly intact, others are decimated by desire for timber, palm oil, soy bean, and cattle grazing