The correct option is 1, 2, 3 and 4.
Explanation
Primary productivity is defined as the amount of biomass or organic matter produced per unit area over a time period by plants during photosynthesis. It is a fundamental functional aspect of an ecosystem that varies based on biological and physical variables.
Statement-wise Analysis:
- Statement 1 is Correct: Primary productivity depends directly on the plant species inhabiting a particular area. Different species possess varying growth rates, leaf surface areas, and physiological efficiencies (e.g., C3 versus C4 pathways) that dictate biomass accumulation.
- Statement 2 is Correct: Environmental factors such as solar radiation (light intensity and duration), temperature, and soil moisture are critical determinants of the rate of photosynthesis.
- Statement 3 is Correct: Nutrient availability (e.g., nitrogen, phosphorus, iron) in the soil or aquatic environment acts as a limiting factor. High nutrient availability typically correlates with higher productivity.
- Statement 4 is Correct: The photosynthetic capacity of plants refers to their inherent physiological efficiency in converting light energy into chemical energy. This internal factor sets the potential limit for productivity.
Key Takeaway:
Primary productivity is influenced by a combination of plant species composition, environmental conditions (light, temperature), nutrient availability, and the specific photosynthetic capacity of the producers involved.