As humans continue to alter the planet, Earth System has entered a dynamic and uncertain Anthropocene era. Characterizing the nonasymptotic or transient (e.g., nonlinear) dynamics of interlinked social-ecological systems (SES), can provide valuable insights into achieving the UN Sustainable Development Goals for a more desirable future. 

However, identifying critical transitions in real-world SES remains a challenge. A significant knowledge gap exists in reliable index framework for characterizing dynamic behaviors within SES changes. These issues are also compounded by the scarcity of long-term datasets spanning entire transition periods, which together limits our comprehension of the Anthropocene landscape dynamics. 

Recently, an international research team led by Dr. LIN Qi and Prof. ZHANG Ke from the Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences (NIGLAS) bridged these gaps by advancing an evolutionary framework that utilizes a dynamic metric based on Rate of Change (RoC) derived from multidecadal socioeconomic and geobiophysical (lake sediment) records. The researchers from China, France, Netherlands, Sweden, Italy, United Kingdom, and South Africa cluster together, and applied this co-evolutionary approach to one of the world's most profoundly disturbed landscapes, the Yangtze River Delta region in East China. 

The study was published in Proceedings of the National Academy of Sciences of the United States of America on April 19. 

By integrating state-of-the-art sedimentary ancient DNA (sedaDNA) metabarcoding, multi-proxy paleoenvironmental analyses, and comprehensive socioeconomic data from Lake Taihu watershed, the researchers elucidated the temporal dynamics of the regional SES over several centuries. Starting in the 1950s, the SES underwent a dramatic shift towards an interconnected and ecologically unsustainable state, driven by a series of deleterious positive feedbacks, exacerbating water eutrophication, soil erosion, air pollution, and ecosystem resilience loss under human stressors. More interestingly, the study revealed a compelling decoupling of socioeconomic development from eco-environmental degradation since the early 2000s, signifying a potentially more sustainable reconfiguration of the regional SES. 

“The recent decoupling signal discloses a sustainable development pattern not observed over the past millennium in this hotspot region”, said Dr. LIN Qi, first author of the study. To avoid the sustainable trap, actually, the local and national authorities have implemented wide-ranging environmental laws and policies, launched conservation and ecological engineering projects, and driven institutional innovations. The study highlights the crucial role of adaptive management and policy intervention in fostering positive transformations. 

This iconic empirical case study also yields essential insights into the resilience and adaptability of SES facing similar sustainability challenges worldwide, for example, where and how to take transformative steps under the UN 2030 sustainability agenda to shift the world on to a sustainable and resilient path. “Adopting the co-evolutionary approaches to address the complexities of SES dynamics, just like in Lake Taihu case, can offer more hope and guidance for achieving a good Anthropocene”, said Prof. ZHANG Ke, corresponding author of the study.

IMAGE: Dynamic changes of intertwined SES from a historical evolutionary perspective. 

CREDIT by ZHANG KE  

Website linkage: https://www.pnas.org/doi/10.1073/pnas.2321303121 

Contact Information 

Ke Zhang at the Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences

Email: kzhang@niglas.ac.cn