Locally Extreme Environments as Natural Long-Term Experiments in Ecology

Many natural phenomena and ecological processes take place extremely slowly, requiring both long-term observations and experiments to investigate them. An alternative is to investigate natural systems that have long-term and stable environmental conditions that are opposed to those of the surrounding ecosystem. Locally extreme environments provide an example of this, and are a powerful tool for the study of slower ecological and evolutionary processes, allowing the investigation of longer term mechanisms at logistically tractable spatial and temporal scales. These systems can be used to gain insight into adaptation of natural communities and their ecological networks. We present a case study and review the literature investigating biological communities at terrestrial mofettes—natural sites with constant geogenic CO2 exhalations and consequent soil hypoxia. Mofettes are often used as natural analogues to future conditions predicted by current climate change scenarios, as model ecosystems for environmental impact assessments of carbon capture and storage systems and for the investigation of physiological, ecological and evolutionary studies of a range of phylogenetically distinct organisms across spatial scales. The scientific power of locally extreme environments is just starting to be harnessed and these systems are bound to provide growing insight into long-term ecological processes, which will be essential for our capacity to adequately manage ecosystems and predict ecological and evolutionary responses to global change.