Soil microarthropods as indicators of exposure to environmental stress in Chihuahuan Desert rangelands

Effects of livestock grazing on aboveground insect communities in semi-arid grasslands of southeastern Arizona

“…This research has been motivated both by the fact that some grasshopper species are considered to be serious rangeland and crop pests and by the fact that grasshoppers are dominant herbivores in many grassland systems in the United States (Otte 1981). Of the relatively few studies that have expanded our knowledge of livestock grazing on grassland invertebrates in the United States, most have examined belowground non-insect invertebrates (e.g., Leetham and Milchunas 1985;Wall-Freckman and Huang 1998;Kay et al 1999).…”

Effects of seasonal grazing, drought, fire, and carbon enrichment on soil microarthropods in a desert grassland

“…While grazing had an effect on microtopography and vegetation (Nash et al, 2004), the short duration of the grazing did not cause sufficient soil compaction to have an effect on the abundance and/or taxonomic composition of the soil microarthropod community. Long-term exposure to concentrated use by livestock has been reported to decrease the abundance and diversity of soil microarthropods (Kay et al, 1999;Kinnear and Tongway, 2004).…”

“…Soil microarthropods affect rates of litter decomposition and are most important in the mineralization of nutrients, especially nitrogen that is immobilized in microbial biomass . The species composition and abundance of soil microarthropods in arid environments vary with vegetation type, topographic position, weather patterns, especially rainfall, and with land use, especially livestock grazing (Cepeda and Whitford, 1989;Cepeda-Pizarro and Whitford, 1989b;Kay et al, 1999). Experiments using simulated rainfall (irrigation) and simulated drought (rain-out shelters) have been used to examine the effects of weather variables on microarthropod communities in shrubdominated ecosystems (MacKay et al, 1986;Whitford et al, 1988;Whitford and Sobhy, 1999).…”

“…Livestock grazing changes soil characteristics such as bulk density, microtopography, and vegetation cover (Kay et al, 1999;Nash et al, 2004). Soil microarthropod abundance and diversity have been reported to be reduced in areas heavily impacted by livestock (Kay et al, 1999;Kinnear and Tongway, 2004).…”

“…Experiments using simulated rainfall (irrigation) and simulated drought (rain-out shelters) have been used to examine the effects of weather variables on microarthropod communities in shrubdominated ecosystems (MacKay et al, 1986;Whitford et al, 1988;Whitford and Sobhy, 1999). Evaluation of the effects of soil properties, vegetation, and run-on, run-off processes on topographic sequences on microarthropod communities has been studied by sampling at various topographic positions on a watershed or disturbance gradients (Cepeda and Whitford, 1989;Cepeda-Pizarro and Whitford, 1989a, b;Kay et al, 1999).…”