Provincial-Level Spatiotemporal Variation and Determinants of Tourism Eco-Efficiency of Forest Parks in the Yellow River Basin, 2013–2022

Based on a balanced panel of nine provincial-level forest-park systems in the Yellow River Basin over 2013–2022 (90 province-year observations), this study measures the tourism eco-efficiency of forest parks and examines its spatiotemporal evolution and determinants. The unit of analysis is the aggregated forest-park system of each province (i.e., all registered forest parks within each province, aggregated to the provincial level), not individual parks. We combine a slacks-based super-efficiency (super-SBM) model—with four inputs, three desirable outputs, and three undesirable outputs—with the global Malmquist–Luenberger (GML) index, standard deviational ellipse (SDE) analysis, and a random-effects panel Tobit model. To remove price effects, monetary variables were deflated to constant 2012 prices; a small number of missing observations were completed by linear interpolation. The results show that: (1) Mean tourism eco-efficiency was 0.778, rising from 0.486 in 2013 to a peak of 1.077 in 2019, declining to 0.897–0.905 in 2020–2021 under the COVID-19 shock, and recovering to 1.143 in 2022. The mean GML index was 1.182, and mean technological change (TC) exceeded mean efficiency change (EC), suggesting that frontier shifts contributed more to measured productivity growth than efficiency change over the study period, although this conclusion rests on the pooled sample and is examined for robustness. (2) Eco-efficiency was spatially heterogeneous, with lower values in the upper reaches and higher values in the middle and lower reaches; the SDE was oriented east–west and its centroid shifted southeast-to-northwest by a modest distance. (3) At the 5–1% level, per capita GDP and tourism revenue share were positively associated with eco-efficiency and forest-park density negatively associated; highway mileage was positively associated only at the 10% level (p = 0.069); forest cover and employee density were not significant. Because the undesirable-output indicators are provincial industrial emissions allocated to forest parks by the tourism-revenue-to-GDP ratio, and because one regressor (tourism revenue share) is mechanically related to a desirable output, the associations reported here should be interpreted as observational, non-causal evidence. Policy implications are drawn accordingly.