Phase Partition

In the context of ecological processes, the term phase partition refers to those processes that are involved in the transfer of elements (generally chemical compounds) from one type of environmental matrix to another. The concept of environmental matrix originates in landscape ecology: The environmental phase or the combination of several phases is more representative of the spatial ambit examined. Soil, water, and biota are examples of typical environmental matrices. Usually, environmental matrices are combinations of the elemental phases, for example, suspended solids in the water column. Phase partition is different from the well-known physical process, such as crystallization or fusion, of phase transition. In these processes, matter switches its state amid the three fundamental states: solid, liquid, and gaseous.* Indeed, when dealing with a living system, besides liquid, solid, and gaseous states, an extra phase, which is the biotic one, is often described. The biotic phase refers to the environmental matrices pertaining to living systems; for example, physiological fluids, organic tissues, or cytoplasm. The biotic phase populates the biosphere introduced in Chapter 1. This phase may be defined as the totality of all ecosystems or the system that integrates all living components and their relationships as well as the interactions with the elements of the other ecospheres: lithosphere, hydrosphere, and atmosphere. Some of the processes involved in matter transfers among spheres are reported in Table 11.1.