Environmental kuznets curve across the distribution evidence from ecological footprints in Central Asia

This study examines whether the Environmental Kuznets Curve (EKC) holds for five Central Asian economies: Kyrgyzstan, Kazakhstan, Turkmenistan, Tajikistan, and Uzbekistan over the period 1993–2022. Unlike most regional studies that use CO 2 emissions, this paper employs ecological footprint as a broader measure of environmental pressure, covering carbon demand, land use, and resource use. The analysis combines FMOLS and DOLS with Method of Moments Quantile Regression (MMQR) and Panel Instrumental Variable Quantile Regression (Panel IV-QR). The long-run estimates support an inverted-U relationship between income and ecological footprint. The quantile results show clear distributional heterogeneity. Income and energy consumption are more strongly associated with ecological footprints at higher footprint quantiles, suggesting that ecological pressure is greater where resource- and energy-intensive production is already more pronounced. The Panel IV-QR estimates confirm the EKC pattern after accounting for potential endogeneity. Foreign direct investment remains statistically insignificant across estimators, offering little support for the Pollution Haven Hypothesis in this sample. Dumitrescu–Hurlin tests indicate that income and energy consumption Granger-precede ecological footprint. The findings highlight the need for energy-transition policies tailored to different levels of ecological pressure.