Table 4 Draft version of metadata extraction questionnaire

Study description

 Study type (BACI/BA/CI)

 Study scope (basin or basins, single wetland, multiple wetlands, wetland complex)

 Number of replications

 Time since intervention

Geographical setting

 Geographical coordinates

 Climate zone

 Average annual temperature

 Average annual precipitation

 Climate conditions during control period (dry, wet, average, unclear)

 Climate conditions during intervention period (dry, wet, average, unclear)

 Surrounding landscape type (forest, agriculture, urban, mixed)

 Elevation at wetland site

 Topography (mountainous, flat terrain)

 Wetland type (bog, fen, mixed mire, limnic shore wetland, other)

 Wetland area

 Underlying geology characteristics

 Underlying soil permeability (high, medium, low, very low)

 Groundwater inflows (yes, no, unknown) [e.g., riparian areas with infiltration]

 Disturbances to groundwater (yes, no, unknown) [e.g., various types of infrastructure]

Intervention

 Type of intervention

Outcome

 Outcome type (groundwater level, groundwater storage, groundwater source proportions)

 Depth of groundwater measurements (upper storage, lower storage, both, not stated, not applicable)

 Measurements outside wetland site (yes, no)

 Number of measurements

 Measurement distance from intervention

Results

 Groundwater level, groundwater storage, groundwater source proportions for control

 Groundwater level, groundwater storage, groundwater source proportions for intervention