  In one interesting analysis—one among many—Ryan has used a complex model tying physiological processes to the physical environment to suggest that increased temperature will make maintenance respiration (which represents the physiological costs of protein synthesis and replacement, membrane repair, and the maintenance of ion gradients in cells) for plants more  difficult.[85]  This is important because the total plant respiration, including maintenance respiration, is an important component of the carbon balance in any ecosystem. Ryan's model is based on observed statistical associations of the different parameters; the underlying mechanisms resulting in the high sensitivity of maintenance respiration to temperature change (as well as changes in many other physical parameters such as carbon dioxide and protein concentrations) remain unknown. Ryan's result is important because of the ongoing climate change through global warming.