GPP, NPP & R Flashcards
1
Q
What is gross primary production (GPP) ?
A
- Chemical energy stored in plant biomass
- KJ / m2 / year
2
Q
What is net primary production (NPP) ?
A
The chemical store left in plant biomass after respiratory losses to the environment (R)
3
Q
How does using fertiliser maximise NPP?
A
- fertilisers provide ions which are taken up by plant root cells
- so more N and P available for protein synthesis
- so faster plant growth
- so increased crop production (NPP)
4
Q
How does the use of insecticides maximise NPP?
A
- insects feed on leaves so decrease number of chloroplasts, so decrease photosynthesis
- insecticides kills insects so NPP increases
5
Q
How does using herbicides to limit interspecific competition maximise NPP?
A
- herbicides kills plants competing with crops
- more ions and light available for crop species
- so faster growth of crops leading to an increased crop production (NPP)
6
Q
How does removing hedge rows maximise NPP?
A
- more space for crops to grow
7
Q
How does growing crops in greenhouses maximise NPP?
A
- limiting factors are controlled to maximise crop production
