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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 type Range Median No. of studies
 All studies 0.7–130 20 84
 Wild ungulates (any intervention) 0.7–130 15.5 73
 Livestock (any intervention) 1.2–123 25 14
 Fencing (exclusion/enclosure, any species) 0.7–125 16.3 77
 Sustained/abandoned/resumed livestock grazing 25–50 45 3
  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
  Herbivore metabolic biomass (kg/km2)
Study type Range Median No. of studies
 All studies 15–10300 500 84
 Wild ungulates (any intervention) 15–10300 465 73
 Livestock (any intervention) 114–5500 2000 14
 Fencing (exclusion/enclosure, any species) 15–3600 480 77
 Sustained/abandoned/resumed livestock grazing 2750–5500 5000 3
  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