Deserts to Savannah Flashcards
What determines broad biome occurrences?
Temperature and precipitation
What are the climatic requirements for deserts?
1) Very low precipitation= Long annual droughts
Rain= cool months
Drought= Hot months
2) Combination with high temperatures
BUT: Can also get deserts in relatively cool and dry environments
Exist almost entirely outside of the tropical zone
What are some characteristics of Desert plants?
1) Short lived, fast life cycle with long-lived dormant seeds
2) Large underground or above ground water-storage bodies e.g. Saguaro cacti
3) Waxy leaves with few stomata= Tend not to lose much moisture= Trapped, can’t escape
4) Species often partition root space to reduce competition= Roots will not overlap
Cactus: Slow growing
How are kangaroos adapted to live in Australia desert?
Dominant desert herbivore
1) Method of travelling= Fast, energy efficient method of travel= Large distances= Can search for food and water
2) Fermentation= Hydrogen by-product is converted to acetate= Provides more energy
How are camels adapted to the desert?
1) Water storage: Can drink 200L of water in 3 mins
2) Fat storage= Hump
3) Ability to deal with dust-storms
What are some other examples of adaptations of animals living in the desert?
Gemsbok= Oryx gazella= High body temperature
Budgerigar= Nomadism= Live in the desert, when good conditions= Come together= MOBILE
ALSO: loosely packed feathers, omnivores, long legs, strong fliers
What are some general adaptions which animals have to extreme environments?
1) Physiological Adaptations e.g. Camel’s hump
2) Nomadism e.g. letter-winged kite
3) Nocturnal
4) Good dispersal ability
5) Locally migratory
6) Heat dissipating e.g. large ears (Cape Hare)
7) Behavioural adaptation: Mouth wide open= Breathing rapidly to try to lose moisture through its lungs to cool down + Long distance flights to water + Carry water in breast feathers
8) Hibernation/Aestivation
What are the climatic features of Grasslands?
Precipitation occurs throughout the year= Temperate grasslands receive rain every month
Seasonal temperatures
Rainy when hot, less rainy when cold
What is a trait of plants living in Grasslands?
1) Have to be able to cope with grazing= Species that grow close to or below ground level
What are some traits of different animals living Grasslands?
1) Herbivores: Synchronised birthing, herding, often overland migrants (Example Wildbeest)
2) Granivores( feed on seeds of plants): Very mobile (e.g. Quelea)
3) Insects: Often rely on camouflage e.g. stick insects
What are some examples of typical grassland species?
1) Grassland plants
2) Ratite birds: Large bodied, flightless vegetarians e.g. Emu
3) Large bodied, herding herbivores e.g. American bison
4) Granivorous birds: Quelea
What are the climatic conditions of Savannahs?
1) Do not receive rain every month
2) Seasons are marked by ‘rainy’ season and ‘dry’ season
Most common in Africa
What is some characteristics of plants in Savannahs?
1) Mix of tropical/subtropical grasslands with scattered trees and shrubs
2) Acacias: Deep tap and wide-ranging roots + Leaf form pre-adapted to heat and water stress + Torns= Minimise herbivory
3) Pampas Grass: Evergreen grass, up to 3m tall
4) Thatch Grass: Up to 1m tall, Unpalatable( not tasty) when old but palatable when resprouting
What are some examples of animals in the Savannah?
1) Bulk grazers: Eat almost any grasses, e.g. Wildebeest and Zebras, eat almost any grasses
2) Selective grazers e.g. Topi, only eat more typically nutritious species
WHAT DOES OBLIGATE GRAZING MEAN?
3) African Elephant: Can keep Savannah open
4) Dung Beetles and Termites: Vital for nutrient recycling
What is the role of fire in Savannah?
Perpetuated by fire (keeps going)= Natural or artificial
Kill young sapling trees
Some plant seeds need during to inhibit dormancy
