Lecture 18: Chapter 18- Terrestrial Ecosystems

Question 1

Know the distribution and dominant plant life forms and soils of the world’s 8 major biomes

Question 2

Be able to rank the biomes in terms of climate (MAT, MAP, seasonality) and plant productivity

Answer 2

*Humid tropical- tropical rainforest, savanna
*Dry-desert, grassland
*Moist subtropical mid latitude- warm temperate deciduous/ coniferous forest, mediterranean
*Moist continental-cool temperate deciduous/ coniferous forest, boreal forest
*Polar-tundra

Question 3

Discuss why biomes are also known as “potential natural vegetation” and discuss typical land usage in each biome

Question 4

Major biogeographical realms

Answer 4

Oceania
Nearctic
Neotropic
Paleartic
Afrotropic
Antarctic
Indo-Malay
Australiasia

Question 5

Indo-malay

Answer 5

python- non venomous and kills prey with constriction

Question 6

Main plants used to classify biomes

Answer 6

trees, shrubs, grasses (graminoids)

Question 7

Graminoids

Answer 7

maintain a higher proportion of biomass in photosynthetic tissue (leaves) because little energy is required for support tissues (stems)

Question 8

Shrubs

Answer 8

invest fewer resources in stems and other supporting structures than trees

Question 9

Trees

Answer 9

woody tissue allows for increased height and access to light, but increase cost (maintenance respiration)

Question 10

8 major terrestrial biomes

Answer 10

Forests (tropical, temperate, confier/boreal)
shrublands
tundra
desert
tropical savanna
temperate grasslands

Question 11

Require 1000 mm of precipitation a year

Answer 11

forests

Question 12

In terms of precipitation, ranks grassland, savanna, and forest

Answer 12

grassland<savanna< forest
trees require more water than shrubs and grasses

Question 13

Arctic Tundra

Answer 13

-tundra is a frozen plain that is located at the highest latitudes of the Northern Hemisphere
-climate is very cold with long and cold winters. growing season 2-5 months.
-presence of permafrost (Gelisols): chills the soil, diminished soil aeration, and slows plant growth
-have an active layer (surface layer) that thaws and freezes seasonally -> creates patterned ground like polygons
*few species and slow growth. taller plants not supported

Question 14

Conifer forests

Answer 14

-cool temperate (mountain ranges) and boreal zones
-dominated by needle-leaf evergreen trees
-cool wet summer and cold winter
-boreal forests typically cover formerly glaciated land

Question 15

Temperate forests

Answer 15

-temperate climate
-more than 1000 mm precipitation per year
-longer growing season than boreal forest
-warmer summer
-broad leaf deciduous and evergreen
-ultisols, inceptisols, and alfisols

Question 15

Temperate forests

Answer 15

-temperate climate
-more than 1000 mm precipitation per year
-longer growing season than boreal forest
-warmer summer
-broad leaf deciduous and evergreen
-ultisols, inceptisols, and alfisols

Question 16

Temperate grasslands

Answer 16

-grazing and human activities can suppress plant growth
-occur in midlatitudes in midcontinental regions where annual precipitation is reduced as air masses move inland

Question 17

Deserts

Answer 17

-low infrequent moisture
-arid regions
-25-35% of earths landmass
-rain shadow of mountains or far inland
-aridisols and entisols

Question 18

Temperate shrublands

Answer 18

-hot dry summers and cool moist winters
-fire
-xeric broadleaf evergreen shrubs
-dwarf trees
-herbaceous understory
-eg. chaparral California
-adaptations of shrubland: drought resistance thick leaves to minimize respiration
-alfisols and entisols

Question 19

tropical savannas

Answer 19

-two layer vertical structure with grasses on the understory and trees and shrubs
-fire adapted vegetation
-woody vegetation is short lived (several decades)
-oxisols, entisols, and alfisols

Question 20

tropical forests

Answer 20

-broadleaf evergreen plants with complex multi story canopy (lianas, epiphytes, strangler figs)
-high diversity of plant and animal life
-high productivity
-6% land surface
-home to many primates
-most life takes place in the canopy NOT the understory
-oxisols and ultisols