Environmental Regulation and Green Total Factor Productivity: A Systematic Review of Policy Effects and Boundary Conditions

Environmental regulation can raise green productivity through innovation and reallocation, while compliance costs, uneven enforcement, and spatial displacement can produce weaker or adverse outcomes. This systematic review evaluates how identifiable environmental-policy instruments affect green total factor productivity (GTFP) and identifies the conditions that bound those effects. A prespecified Web of Science search yielded 636 unique English-language records; 353 full texts were assessed, and 350 empirical studies were included. The evidence base is predominantly China-focused, with 110 city-level and 87 provincial or regional studies and only three cross-country or national studies. Study-level coding distinguished policy family, evidence role, causal-inference tier, effect direction, mechanism, nonlinearity, spatial process, and reporting strength. Heterogeneous policy contrasts, outcome scales, and estimands precluded a common effect-size meta-analysis, so a PRISMA- and SWiM-consistent structured synthesis was used. Positive findings occurred in 176 studies (50.3%), alongside 84 mixed or conditional and 63 nonlinear or threshold findings. Within the primary lane of 146 direct quasi-experimental studies, 106 (72.6%) were positive. Named pilots and market-based instruments had the strongest convergent patterns; selected green financial and fiscal policies were also favourable, whereas command-and-control, information and composite regulation were more dependent on enforcement, finance, policy intensity and analytical scale. Seventy-six studies reported nonlinear relationships and 38 evaluated spatial effects, showing that local gains may coexist with relocation or uneven spillovers. The evidence supports a predominantly positive, policy-specific, and conditional relationship. Its transferability beyond the Chinese institutional setting remains limited.