Using NEA, it is possible to demonstrate how the connections that make up the network are beneficial for the component and the entire ecosystem. Figure 5.2 presents a very simple example, presuming steady-state (input = output) and first order donor determined flows, which is often used in ecological modeling. Figure 5.2a shows the throughflow and exergy storage (based on a retention time of five time units) in the two components with no coupling, i.e., no network connections. Making a simple connection between the two links them physically, and while it changes their individualistic behavior, it also alters the overall system performance. In this case, the throughflow and exergy storage increase because the part of the flow that previously exited the system is no used by the second compartment, thereby increasing the total system throughflow, exergy stored, and average path length. The advantages of integrated systems is also known from industrial ecology in which waste from one industry can be used as raw material for another industry (see, e.g., Gradel and Allenby, 1995; McDonough and Braungart, 2002; Jorgensen, 2006).
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