Final answer:
Terrestrial biomes' NPP varies primarily with temperature and moisture, whereas in aquatic ecosystems, light penetration, dissolved oxygen, and nutrients are the main factors affecting NPP.
Step-by-step explanation:
Variation in Net Primary Productivity (NPP) in terrestrial biomes is predominantly associated with the abiotic factors of temperature and moisture. These factors influence plant growth, photosynthesis rates, and thus the biomass production within different biomes. For example, tropical wet forests have high NPP due to warm temperatures and abundant water, whereas deserts and tundra have low NPP due to extreme temperatures and limited water availability.
In aquatic ecosystems, the variation in NPP is most affected by abiotic factors like light penetration, dissolved oxygen, and the availability of nutrients. The depth at which sunlight cannot reach significantly affects photosynthesis and therefore productivity. In contrast to terrestrial biomes, abiotic factors such as temperature and moisture extremes are less limiting to aquatic organisms.