Plants primarily respond to temperature and humidity because these two environmental elements significantly influence their physiological processes, growth patterns, and overall health. Temperature affects metabolic rates, photosynthesis, respiration, and transpiration, while humidity levels influence water availability and the plant's ability to regulate water loss through transpiration.
For instance, higher temperatures can increase the rate of photosynthesis up to a certain threshold, while extremely high temperatures may stress the plant and hamper its growth. Similarly, humidity levels can affect the stomatal opening, which regulates gas exchange and water loss, thus impacting how effectively a plant can photosynthesize and maintain its turgor pressure.
While factors such as soil texture, wind speed and direction, and the type of neighboring species do play roles in the overall growth and survival of plants, temperature and humidity are fundamental to their immediate physiological responses and adaptations. These parameters directly interact with the plant's metabolic functions and contribute to its responses to environmental changes.