Data from: A palaeolimnological perspective to understand regime-shift dynamics in two Yangtze-basin lakes

Natural and human disturbances have caused widespread regime shifts in
shallow lakes of the lower Yangtze basin (LYB, China) resulting in a
severe decline of ecosystem services. Improved understanding of the
relationship between environmental forcing and ecosystem response, and the
mechanisms behind regime shifts has significant implications for
management. However, the patterns of these regime shifts and the
underlying internal mechanisms, are less known. In this study, two typical
lakes (Chaohu and Zhangdu) from the LYB were selected to determine the
trajectories of ecological regime shifts, both of which transitioned from
vegetation- to plankton-dominated states several decades ago. Ecological
trajectories since the 1900s in both lakes were reconstructed using
palaeolimnological proxies, mainly diatom assemblages. Although results
show that regime shifts occurred in both lakes in the 1970s and the 1950s
respectively, their inherent mechanisms were different. In Lake Zhangdu,
altered hydrological conditions pushed the ecosystem across an ecological
threshold, providing an example of a driver-mediated regime shift. In Lake
Chaohu, ongoing nutrient loading influenced ecosystem processes and drove
the lake to an alternative stable state, potentially presenting an example
of a critical transition after a loss of resilience. This research
indicates that palaeolimnological perspectives can provide insights into
regime-shift changes, as well as important information regarding which
restoration methods should be tailored to individual lakes.