On November 18, Nature, a magazine of the U.K., published the important research results about ecological system mutation and its early signals of Doctor Wang Rong, a researcher from Nanjing Institute of Geography & Limnology, together with Southampton University of the U.K. and Wageningen University of Holland.
Ecological system changes often have a mutational site, that is, it will suddenly change to another stable condition from a stable condition after long-time energy gathering. This condition change is often unexpected, and will cause serious consequences and is difficult to recover, e.g. quick shrinking of Arctic Lake and changes of ecological system structure, as well as algal bloom of eastern lakes of China. With the background that global human activities are increasing, people cannot determine whether the ecological system is running in a safe range, and it is more difficult to expect the future development of the ecological system.
Researches on early signal extraction of the ecological system mutation are useful for avoiding the occurrence of disastrous events. Therefore, researches on the structure, resistance, feedback mechanism of the ecological system are the main direction of the field of ecology. However, many current researches are mainly based on the critical slowdown theory, and most results are completely based on models and are not inspected by natural ecological system data, so they have lots of uncertainty, and whether its theory basis is appropriate to actual applications is always debatable.
This research is sponsored by Global Change Major Research Project Program of The Ministry of Science and Technology of the People’s Republic of China. Taking Yunnan Erhai as an example, it uses paleolimnology and modern lake monitoring data combined with models to analyze and study the change characteristics of the ecological system structure during eutrophication of Erhai, discuss the early signal characterization of lake ecological system mutation, and reveal that the ecological system has frequent fluctuant features before mutation, i.e. flickering phenomenon, under the condition of strong interference. This research provides important theoretical basis for early signal extraction of the ecological system mutation. Meanwhile, the research believes that the flickering phenomenon should be paid attention to as for safety evaluation of the ecological system. This research provides new ideas for using paleolimnology and simulation methods to carry out long-term change studies on complicated ecological system.