ecosystem ecology (BB10205)

Question 1

ecosystem ecology

Answer 1

organism complex and whole complex of physical factors

Physical/chemical: wind ,currents, heat and geochemistry

Biological: communities, producers, consumers

Question 2

ecosystem components

Answer 2

producers
consumers
decomposers
abiotic components:
- water
- atmosphere
- soil minerals
- climatic variables

emphasis on function not species
pool of energy/matter for each component- how things flow between

Question 3

Gw predicts

Answer 3

on av temp increase - shift temp distribution and incr occurrence of extreme events
Larger number of extreme hot days, more drought
Less rain on the days rain is light but heavier when it does rain- storms
Heavy precipitation extremes

Question 4

Why care about ecosystem ecology?

Answer 4

goods and service

understanding of function of ecosystems to improve management because human activities are changing them

Question 5

ecosystem research core areas

Answer 5

transformations and interactions of energy and matter within an ecosystem
Energy budgets and factors that control energy transfer
monitoring changes
sustainability: carrying capacity (management and harvest), restoration

How human activities affect these processes

Question 6

productivity

Answer 6

rate of energy capture and conversion to chemical bonds

Question 7

Primary producers efficiency

Answer 7

99% of solar energy is reflected/not absorbed

Loses some by respiration and rest converted into biomass

Question 8

GPP

Answer 8

rate at which energy is captured and assimilated by producers. Includes the use of captured energy by the producers for their own metabolism via respiration

Question 9

NPP

Answer 9

Rate of energy assimilated and converted to biomass by producers in an area

Question 10

NPP=

Answer 10

GPP-R

Question 11

GPP %

Answer 11

1% of solar energy captured by PS is GPP

Question 12

HOw is GPP distributed

Answer 12

60% of GPP respired

40% of GPP converted to biomass/NPP

Question 13

ways of measuring changes

Answer 13

measuring changes in producer biomass
changes in CO2 uptake and release
O2 uptake and release
Remote sensing

Question 14

Measuring changes in producer biomass

Answer 14

measure mass of producers at the beginning and end of growing season
Tells you how much biomass has been accumulated
Useful for comparing agric processes
estimates NPP
Variable across years

Question 15

Changes is CO2 uptake and release

Answer 15

Measure CO2 in a container in the light and dark. Decr in CO2 in the light is NPP, difference between light and dark is GPP (GPP = NPP + resp)

Question 16

Measuring changes in O2 uptake and release

Answer 16

CO2 disperses too fast in aquatic environments
Measure dissolved O2 instead- similar but reversed relative to productivity
Incr O2 measured in light, Consumption of O2 measured in dark

GPP = NPP (change in O2 in light) +R ( change in O2 in dark)

Question 17

Remote sensing

Answer 17

can measure from a great distance (planes/satellites)
Using absorbance and reflectance of chlorophyll to map global changes in producer biomass
Reflectance of light of different wavelengths

Question 18

NPP distribution across earth

Answer 18

Terrestrial systems show highest productivity in the tropics
Tropical rainforests most productive ecosystems
PS works best at high temps and more light- at the equator

Question 19

Patterns of NPP in aquatic systems

Answer 19

marine systems lower in productivity per unit area
Temp still important, but being near coast more important
Aquatic systems along coasts highly productive per unit area with estuaries and coral reefs most productive
Movement of water affects climate/temp eg gulf stream

Question 20

Temp and rainfall

Answer 20

positive correlation with productivity

Question 21

Nutrients

Answer 21

N and P can be limiting to productivity

Most biomasses limited by nutrients- by adding them you incr productivity

Question 22

What effects PP i aquatic ecosystems

Answer 22

Temp
Light: depth of light penetration alters productivity in the photic zone
Nutrients (N,P,Fe)

Question 23

secondary production

Answer 23

From producer to 1st consumer

Question 24

secondary productivity positively correlated to

Answer 24

NPP

suggests more available energy from producers results in more consumer growth and reproduction