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Table 3 Quantitative data on grazing/browsing pressure (herbivore density and biomass)

From: Manipulating ungulate herbivory in temperate and boreal forests: effects on vegetation and invertebrates. A systematic review

 Herbivore density (no. of animals/km2)
Study typeRangeMedianNo. of studies
 All studies0.7–1302084
 Wild ungulates (any intervention)0.7–13015.573
 Livestock (any intervention)1.2–1232514
 Fencing (exclusion/enclosure, any species)0.7–12516.377
 Sustained/abandoned/resumed livestock grazing25–50453
 Herbivore metabolic biomass (kg/km2)
Study typeRangeMedianNo. of studies
 All studies15–1030050084
 Wild ungulates (any intervention)15–1030046573
 Livestock (any intervention)114–5500200014
 Fencing (exclusion/enclosure, any species)15–360048077
 Sustained/abandoned/resumed livestock grazing2750–550050003
  1. The table is based on study averages (presented as ranges and medians) of grazing/browsing pressure in areas exposed to high herbivory (e.g. unfenced control plots in fencing studies). Reported herbivore densities have been converted by us to metabolic biomass (see Additional file 6), and livestock densities have been adjusted for length of grazing season (see "Methods"). Note that quantitative data on grazing pressure were available for only three of the 17 studies of sustained/abandoned/resumed grazing by livestock (or reindeer) included in the review