The table below describes four different ecosystems and the amount of energy converted into plant biomass each year in each ecosystem:
| Ecosystem | Description | Energy converted into plant biomass (kJ m−2 yr−1\text{kJ m}^{-2}\text{ yr}^{-1}kJ m−2 yr−1) |
|---|---|---|
| P | Temperate deciduous forest | 32 000 |
| Q | Tropical rainforest | 50 000 |
| R | Open wild meadow | 12 000 |
| S | Intensive crop field | 28 000 |
Name three abiotic (non-living) factors, other than carbon dioxide concentration, likely to affect the rate of photosynthesis in these ecosystems.
Ecosystems R (open wild meadow) and S (intensive crop field) experience the same climate. Suggest two reasons, other than selective breeding of the crops, why more energy is converted into plant biomass in ecosystem S than in ecosystem R.
What is meant by the term selective breeding?
Describe how you could use a quadrat to estimate the total dry plant biomass in Ecosystem R, which has a total area of 500 m2\text{m}^2m2.
