The sun, being the main source of energy, is taken up by plants. This energy streams through a track known as biota, which may be symbolized by a pyramid made up of strata. Each species depend on another as the energy moves up the layers. This successive movement from the soil, which is the base of the plants, insects feeding on plants and later fed on by birds eventually end with the large carnivores.
The large carnivores finally die and decompose into the soil. However, the soil needs rain to support the plants. On the other hand, Patchett and Wilhelm look at the pyramid of land in relation to its degradation, especially by agents of erosion such as water. When it rains, surface runoff erodes fertile topsoil depositing the load in rivers. Bare land is less productive and is one of the main causes of global warming. This process further leads to accelerated runoff hence causing the surface water to evaporate.