0 1 0 0 0 0 0 0 mesophyll leaves, palisade parenchyma cells [1] 0 0 0 0 1 0 0 0 store water leaves chloroplasts [2] 0 0 0 0 1 0 0 0 sunlight [3] 0 0 0 0 1 0 0 0 carbon dioxide [4] 0 0 0 0 0 1 1 1 process photosynthesis [5] 0 0 0 0 0 0 0 0 output oxygen [6] 0 0 0 0 0 0 0 0 output glucose [7] 0 0 0 0 0 0 0 0 output water [8]
When an interaction occurs, the process itself is placed within the node. In this process, you can see that it is both convergent and divergent for the same node: ‘photosynthesis’.
Placing a process within a node appears to contradict the general model of the causal graph of a single process, but this is not the case. At the ends of the network, we have observable and measurable inputs and outputs in the nodes. The structure as a whole provides a detailed analysis of a component of other processes: the oxygen cycle and the carbon cycle. It is also involved in the water cycle, the uptake and release of water, as can be seen in evaporation. The release of glucose forms the basis of plant growth, which is essential in any ecological system.
Processes can be studied at various levels. This diagram even includes a visualisation of yet another level: the schematic representation of the light-dependent processes involved in photosynthesis, found within the ‘photosynthesis process’ node itself. There are therefore three levels of analysis involved.