Towards ecological security: Two-thirds of China’s ecoregions experienced a decline in habitat quality from 1992 to 2020

• An analytical framework for habitat quality using InVEST-Sen’s-MK-Hurst-OPGD model was established. • The spatiotemporal distribution and drivers of habitat quality at multiple scales in China were revealed. • The land use evolution pattern of China’s ecological zones over the past 30 years was analyzed. • From 1992 to 2020, the habitat quality degraded in China’s ecological zones exhibited an increasing trend, driven by vegetation index, temperature, and slope. China’s six major ecoregions are cross-administrative regions that coordinate ecological security and socioeconomic development, making the preservation of regional ecological security critically prominent. However, differences in the economic development modes between administrative regions threaten the maintenance of biodiversity in these ecoregions. Currently, the spatiotemporal evolution of habitat quality (HQ) in China’s ecoregions and its drivers have not been fully analyzed. In this study, the InVEST model, trend analysis methods, and the optimal parameter-based geographic detector (OPGD) model were used to reveal the spatiotemporal distribution of HQ in China’s six ecoregions over the past 30 years and its driving mechanism. The findings indicated that since 1992, land use alterations and conflict patterns differed throughout the ecological zones, and construction land exhibited an increasing trend in all six zones. The national HQ initially decreased and then increased, with a multi-year average of 0.6304. The Qinghai–Tibet Plateau Ecological Region (QTPER), Northeast Ecological Region (NEER), and Southeast Ecological Region (SER) had higher HQ values, while the Northwest Ecological Region (NWER) had the lowest value. The HQ in the NEER continuously declined. The longitudinal distribution of the HQ exhibited a weak W-shaped pattern from west to east. The HQ demonstrated an upward tendency in the NWER and QTPER and a downward trend in the SER, NEER, and Yangtze River and Sichuan–Yunnan Key Ecological Region (YRSYKER). Except for the SER, the Moran’s I values in the other ecoregions were greater than 0.80. The HQ was mainly high in the QTPER and NEER and low in the NWER and the Yellow River Key Ecological Region (YRKER). The main factors influencing the spatiotemporal heterogeneity of HQ differed between ecoregions. Among them, natural factors including the annual average vegetation index, elevation, and slope were the long-term dominant driving factors. The integrated HQ comprehensive analytical framework offers effective methodologies and empirical data for HQ evaluation and monitoring at different scales in China.