Evaluation of ecological carrying capacity in Yangtze River Economic Belt and analysis of its spatial pattern evolution

The ecological carrying capacity (ECC) is a critical part of the study on regional sustainable development. Combining social, economic and environmental status of the Yangtze River Economic Belt (YREB), this paper constructed the pressure-state-response (P-S-R) model, selected 32 indicators to build the evaluation index system of the ECC in YREB and used the method of entropy weight TOPSIS and spatial econometric to study the spatial pattern distribution and evolution characteristic of the ECC level in YREB. The results showed that: (1) the variation trend of ECC level in YREB showed an "inverted U-shaped" trend, which firstly increased and then decreased, and the gap of ECC between different regions did not change significantly during the observation period; (2) there were significant regional differences in the ECC level of the YREB. From the provincial level, the annual regional differences were mainly caused by inter-regional differences, while from the municipal level, the annual regional differences were mainly caused by intra-regional differences; (3) there was a significant spatial agglomeration effect in the regional ECC of the YREB. At the provincial level, the spatial agglomeration degree of ECC showed a trend of continuous strengthening, while at the municipal level, the spatial agglomeration degree of ECC showed a significant trend of weakening; (4) the ECC index of the YREB had obvious spatial convergence characteristics, and the lagging regions had a significant catch-up effect on the leading regions.