Abstract:Outstanding ecological and environmental problems such as deep environmental pollution accumulation and poor water quality compared with the national average are haunting the Yellow River basin. As one of the important ways to improve the water quality of the Yellow River Basin, wastewater reduction depends on the improvement of related technologies. Therefore, unbiased technological progress is of great significance to realize ecological protection and high-quality development of the Yellow River Basin. Based on this, this paper takes 97 cities in the Yellow River Basin as spatial research units, and constructs an index system of biased technological progress in wastewater reduction. Nonparametric method is adopted to measure the urban biased technological progress in wastewater reduction in the Yellow River basin as a whole and respectively its upper, middle and lower reaches from 2010 to 2020 to determine whether technological progress is biased towards wastewater reduction. Moreover, Dagum Gini coefficient, Kernel density estimation, σ convergence and absolute β convergence are used to analyze its dynamic evolution trend, spatial differences and convergence characteristics. Research findings are as follows: (1) Wastewater reduction biased technological progress has not occurred in the Yellow River Basin during the study period the development of wastewater reduction biased technological progress in the Yellow River Basin shows an evolutionary trend of "dispersion→convergence", and the contribution of wastewater reduction biased technological progress to total factor productivity decreases in the late study period. (2) After 2016, the gap in wastewater reduction bias technology progress between cities in the basin gradually narrows, showing a more balanced situation. (3)Absolute β convergence instead of σ convergence is identified in wastewater reduction biased technological progress in the whole basin and the upper, middle and lower reaches of the basin, with the rate of convergence in descending order, lower reaches, upper reaches, middle reaches. Judging from the result, it is proposed that in the Yellow River basin, the discharge standard of water pollutants should be reasonably adjusted and the relevant system of emission trading should be improved.
