Lecture 31. Terrestrial Ecosystems: Forests and Grasslands Flashcards
What is the climograph ?
Relationship of climate to biomes
What plants grow in 100-200mm ?
Only grasses can survive
What plants grow at 300mm ?
Shrubs
What plants grow at 400mm ?
Solitary trees
What plants can grow over 400mm ?
Dense trees/forests
Where is a tropical forest found ?
23.5 latitiude of equator
How much rain in a tropical forets per year ?
2500m/year
What is a tropical deciduous forest ?
Areas with distinct wet and dry season
How much of forests in the tropics does the tropical deciduous forest represent ?
32%
How much of forests in the tropics does the tropical rainforest represent ?
25%
What is a tropical dry forest /
Lowland area with prolonged dry season and scarce rainfall
What is the tropical dry forest characterised by ?
Thorny shrubs and trees and succulents
How much of forests in the tropics does the tropical dry forest represent ?
43%
What type of plants is there in a tropical deciduous forest ?
Trees and shrubs deciduous
What is a tropical rainforest chracterised by ?
Tall, slender trees
What perecntage of all plant species in tropical rainforests are trees ?
70%
Why is there 70% trees in tropical rainforests ?
Lots of plants and animals species which need trees
What are epiphytes ?
Plants that lives on other plants
Are epiphytes parasites ?
No
What results in rapid nutrient cycling ?
High temperature and rainfall throughout the year
How can recycling occur ?
Leaf littering
What are the types of temperate and boreal forests ?
- Temperate deciduous forest
2. Coniferous forest
What breaks down litter ?
Detrivores
What type of roots do tropical forests have and why?
- Root mats
2. Prevent washing away by heavy rain
What does leaching result in ?
Poor soil development
What can deforestation result in soilwise ?
Leaching
Where are temperate and boreal forests found ?
Mid latitudes to artic circle
What is one key thing about temperate and boreal forests /
Seasonality
What is an adaptation to seasonality ?
Perenating bud
Describe the seasons of a boreal forest ?
Winter: long and cold
Summer: Short and wet (warm)
What type of soil is in boreal forest ?
Thin, nutrient poor and acidic
What are the principle trees in boreal forests ?
Conifers
Why are conifers the principal trees in the boreal forest ?
Can withstand cold, drought and snow
What percentage of the worlds forests are temperate?
16%
What are two examples of conifer trees ?
- Spruce
2. Pine
How is spruce adapted to snow ?
Falls of branches
What is a common occurence of boreal forests ?
Forest fire
How is pine adapted to fire ?
Has tough bark and less resin
Where are temperate forests found ?
Mid latitudes where sufficient moisture to support trees
What are the seasons in the temperate forest ?
Summer: Warm
Winter: Cold
What is the growing season in temperate forest ?
6-9 months
What is the precipitation in temperate forests ?
Relatively high and throughout year
What type of soil do temperate forests have ?
Deep and fertile, thick litter layer
What is involved in deciduous habit ?
- Tree growth
- Light penetration
- Hydrological cycle
- Litter production
- Soil fertility
What is grassland characterised by ?
Long seasonal drought
What is the annual rainfall in grassland /
250-750mm/year
What is the problem with grasslands ?
- Too dry for dense woodland
2. Too wet for desert
What are the two types of grassland ?
- Temperate grassland
2. Tropical grassland
Where does temperate grassland occur ?
Where rainfall is intermediate between desert and temperate forest biomes
What type of seasons does temperate grassland have ?
- Long dry season
2. Col winters - dormant
What are two things that occurs in temperate grasslands ?
- Grazing
2. Occasional fires
Describe the fertility of temperate grasslands ?
Low rainfall - low leaching - fertile soils
What can temperate grasslands be converted to ?
Tillage for corn and wheat crops
Where are tropical grasslands ?
Savanna
What is the climate of a tropical grassland ?
Warm
What is the seasons in the tropical grasslands ?
- Long dry season - dormant
What often happens in tropical grasslands ?
Regular fires
What is the difference between tropical and temperate grasslands ?
Tropical have lower nutrient status
What are fire and grazing important elements in ?
- Nutrient cycling
2. Preventing tree growth
How is savanna distribution determined ?
Soil moisture
What do savanna soils have ?
High porosity and little mulch
What does the high porosity and little mulch of the savanna result in ?
Rapid drainage with loss of nutrients
What is savanna tree regeneration determined by ?
Fire and grazing
What are some adaptations to grazing ?
- Basal meristem
- Tillering
- Rhizomes
- Secondary chemical compounds
- Spines
What adaptations to grazing are particularly useful for fire ?
- Basal meristem
- Tillering
- Rhizomes
What are agricultural uses of land in ireland ?
- Pasture
- Rough grazing
- Hay/silage
- Tillage