Complex sentence: PAR can also be expressed in W/m 2, but because photosynthesis is a quantum process, PPFD is generally preferred by plant biologists, but W/m 2 measurements are important in energy balance considerations for photosynthetic organisms.
Split into simpler sentences: PAR can also be expressed in W/m 2. Because photosynthesis is a quantum process PPFD is generally used by plant biologists, but W/m 2 measurements are important in energy balance considerations for photosynthetic organisms.