Recently pioneered field of ecology- Last 30 years
Landscape- view from an airplane
Landscape Ecology- Branch of ecology that studies ecological patterns and processes at a large scale
Scale- Areas on an order of a few Km2, to state sized, to entire countries
Fragmentation- Process in which a continuous landscape is broken into smaller patches.
Patches- Areas of similar vegetation, sourrounded by different types of vegetation
Ex forest- patch Field- patch
Fragmentation usually the result of disturbances
- natural causes of fragmentation
1) volcano 2) earthquakes 3) tidal wave 4) hurricanes 5) fires
Human caused fragmentation- agriculture, development of cities/suburbs, forestry
1) size 2) shape 3) # of patches 4) arrangement
Processes fragementation results from disturbances
GIS- Geographic information system software- Arcmap
Ecosystems- all the organisms in an area plus all the abiotic factors that those organisms interact with.
Rainfall, temp, soils, rocks, fire
1) Primary productivity- amount of CO2 that is transformed into organic carbon per unit are, per year.
- measure of photosynthetic activity
- measure of plant activity
Normally ecologists measure plant growth
- Measurements go from 5(deserts) to 10,000(tropical forests) kg of CO2 fixed per year per hectare
What factors affect primary productivity?
1) sunlight- insolation 2) rainfall/ precipitation 3) temperature
4) seasonality 5) soil/nutrients
2) Gross Primary Productivity- Measure of total carbon fixed (photosynthesis) by plants in an ecosystem
3) Net Primary Productivity- Total fixed carbon minus the energy lost to respiration
Measured by looking at changes in plant growth In an ecosystem
Plans use Photosynthesis make sugars
Respiration break the sugars down for ATP
Photosynthesis= respiration + grow
(sugars) (burn sugars) (Left over sugars)
Large variation in NPP
1) NPP generally is higher in warmer climates
2) NPP is also generally higher in wetter sites, but there is a limit.
As rainfall increases NPP rises, but only to a point NPP
3) Nutrients- can limit NPP. Generally, NPP is higher in richer soils
Explanation for the Asymptote:
1) In rainier sites, its is also cloudier
2) Leaching of nutrients at really rainy sites may limit NPP as well
1) Grasslands- cut the vegetation at ground level