Testing the limits of resistance: a 19-year study of Mediterranean grassland response to grazing regimes

Published source details Sternberg M., Golodets C., Gutman M., Perevolotsky A., Ungar E.D., Kigel J. & Henkin Z. (2015) Testing the limits of resistance: a 19-year study of Mediterranean grassland response to grazing regimes. Global Change Biology, 21, 1939-1950.
Share Tweet Email

Actions

This study is summarised as evidence for the following.

	Action	Category
	Other biodiversity: Use seasonal grazing Action Link
	Other biodiversity: Use fewer grazers Action Link

Other biodiversity: Use seasonal grazing

A replicated, randomized, controlled study in 1993–2012 in grassland in north-eastern Israel (same study as (2)) found that plant diversity and cover varied between plots grazed by cattle in different seasons, for four of five plant functional groups. Plants: Plant diversity was higher under early or continuous grazing, compared to late grazing (data not reported). Cover of tall annual grasses was higher in late-grazed plots, compared to early-grazed (34% vs 14% cover), but only with moderate grazing, rather than heavy. Cover of tall perennial grasses was higher with one of six timing-intensity combinations, but this difference disappeared by the end of the study. Cover of short grasses was higher in early-grazed plots, compared to late-grazed (2–41% vs 1–24%), but similar to continuously grazed plots (1–37%). Cover of annual forbs was higher in early-grazed plots, compared to late-grazed, with moderate grazing, but not with heavy grazing (19–60% vs 4–39%). Cover of perennial forbs did not vary between grazing timings. Methods: In 1993, eight plots were established. Half were grazed continuously (January–October) and half were grazed seasonally. In seasonal plots, half of the plot was grazed early (January–April/May) and half was grazed late (April/May–October). In addition, half of the plots were moderately grazed (0.55 or 1.1 cow-calf pairs/ha for continuous and seasonal, respectively) and half were heavily grazed (1.1 or 2.2 cow-calf pairs/ha). Plants were surveyed every spring, every two steps along permanent transects.
Other biodiversity: Use fewer grazers

A replicated, randomized, controlled study replicated study in 1993–2012 in grassland in north-eastern Israel (same study as (5)) found no difference in plant diversity in plots grazed by cattle at moderate, compared to heavy, intensities. The cover of three of five plant functional groups varied between moderately and heavily grazed plots. Plants: Plant diversity did not differ between moderately and heavily grazed plots (data not reported). Cover of tall annual grasses was higher in moderately, compared to heavily, grazed plots for two out three grazing timings (7–52% vs 2–23% cover, no difference for early-grazed plots). Cover of short grasses was lower in moderately, compared to heavily, grazed plots (1–30% vs 3–41%), with the biggest differences in continuously, rather than seasonally, grazed plots. Cover of tall perennial grasses was lower under moderately, compared to heavily, grazed plots for one of three grazing timings, but this difference had gone by the end of the study. There were no differences in cover of perennial or annual non-grass plants between grazing intensities. Methods: In 1993 eight plots were established with half grazed continuously (January–October) and half grazed seasonally. In seasonal plots, half the plot was grazed early (January–April/May) and half late (April/May–October). In addition, half the plots were subject to moderate grazing (0.55 or 1.1 cow-calf pairs/ha for continuous and seasonal respectively) and half to heavy (1.1 or 2.2 cow-calf pairs/ha). Plants were surveyed every spring every two steps along permanent transects.