Decomposition and Decoupling Analysis of the Driving Factors of the “Water–Carbon–Ecological” Footprint in the Eleven Provinces and Municipalities of the Yangtze River Economic Belt

Studying the spatio-temporal evolution characteristics of the “water–carbon–ecological” footprint and the decoupling status of its main driving factors is of paramount importance for achieving sustainable development in society. Based on quantifying the footprint family, this study constructs an integrated driving factor analysis model of “Kaya–LMDI–Tapio”, screens the main driving factors influencing the footprint family, and conducts decoupling analysis. The research results indicate that: (1) The water, carbon, and ecological footprints of the Yangtze River Economic Belt from 2002 to 2017 were 1534.265 billion cubic meters, 61,672.89 million hectares, and 45,528.76 million hectares, respectively. (2) The main driving factors for water, carbon, and ecological footprints were economic effect factors, agricultural production scale factors, and economic effect factors. (3) During the research period, the decoupling trends between the water, carbon, and ecological footprints and their main driving factors presented a transformation from a weak decoupling state to a strong decoupling state, the decoupling index value decreased initially and then increased, and the decoupling index value showed a downward trend. These findings provide a quantitative basis for the formulation of differentiated basin management policies, indicating that, through the collaborative promotion of technological innovation and institutional innovation, the leap from relative decoupling to absolute decoupling can be achieved, which has important reference value for the sustainable development governance of global river basins.