ABSTRACT
Our study on communities in the last chapter emphasized biotic interactions among species comprising the community without explicitly considering the abiotic factors involved in such a relationship, such as air, light, soil, and water. We now turn our attention to functional relationships among species by focusing on the transfer of material and energy among them and their interactions with the abiotic factors (Figure 13.1). Thus, we turn our attention to ecosystems, de˜ned as the interaction of the biotic, organisms and species living in an area, and abiotic factors. Furthermore, we will be less concerned about the species themselves and more concerned about their functions and their role in ecosystem processes. Many times, we will lump species into compartments or pools according to their functions.
