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Land use, particularly clear-cutting, can affect or change the carbon balance in headwater streams. Yet, there is still limited knowledge about forest clear-cut effects on riparian groundwater and greenhouse gas (GHG) emissions from headwater streams and how to manage riparian buffer zones to mitigate GHG emissions and elevated groundwater concentrations. In this study, I investigated if the relative area of clear-cutting (%) in the catchment affected concentrations and fluxes of organic and inorganic carbon (C) at 15 headwater streams and associated riparian groundwater, as well as if riparian buffer zones can mitigate potential clear-cut effects on C concentrations and fluxes by comparing sites with different buffer zone widths. To test the influence of forest management and buffer width, I used multiple linear mixed-effects models between clear-cut sites and control sites. The results showed no overall clear-cut effects on most C forms, except for carbon dioxide (pCO₂), which may be due to most watersheds being under the forest clear-cut threshold (<30%) expected to observe changes in export. The results also showed that wider buffer zones yielded lower pCO₂ in clear-cut streams, indicating a buffer zone effect. This could be because wider buffers increase stream shading, leading to lower temperatures and lower heterotrophic respiration rates that reduce pCO₂. For riparian groundwater, clear-cut sites had higher TOC concentrations near the stream than upslope. Meanwhile, control sites showed the opposite pattern. This suggests higher DOC transport because of higher groundwater tables after clear-cutting. To better understand this effect, hillslope and stream flow calculations should be included to better understand the hydrological connectivity between streams and the groundwater. My findings suggest that, overall, buffer zones do not mitigate GHG emissions as initially thought but that a larger dataset with more observation could yield different results.