Environmental Systems and Societies

• Atmospheric pressure decreases as altitude increases, resulting in lower air density at higher elevations.
• Air temperature also decreases with increasing altitude due to the thinner atmosphere allowing more heat loss by radiation.
• All flows of energy are governed by the laws of thermodynamics. 1. Conservation of energy: Energy in an isolated system, can be transformed but cannot be created or destroyed. 2. Entropy, the amount of disorder in a system, increases over time. In other words, energy in a system will try dissipate itself to a lower energy level. This is why there is a decrease in the available energy as we move along a food chain.
• The first law of thermodynamics states that energy cannot be created nor destroyed; it only changes form. The second law states that entropy (disorder) always increases within any closed system.
• Primary production refers to the conversion of light energy from the sun into chemical energy by plants and algae.
• Secondary production involves the consumption of primary producers by herbivores, which then become prey for carnivorous animals.