Responses of plants to grazing are better understood, and more predictable, than those of consumers in North American grasslands. In 2003, we began a large-scale, replicated experiment that examined the effects of grazing on three important arthropod groups-beetles, spiders, and grasshoppers-in shortgrass steppe of north-central Colorado. We investigated whether modifications of the intensity a...

This study shows how data from very different disciplines can be combined to address questions relevant to contemporary conservation and understanding. This novel, interdisciplinary approach provides new insights into the role of economic factors as a driver of biodiversity loss in the uplands. Biodiversity levels have varied considerably over 400 years, partly as a function of land management,...

in arid and semi-arid rangelands, grazing as one of the natural or human induced processes has direct and indirect effects on structure and dynamics of plant community and ecosystems. a study was done to analyze the effects of grazing on plant species diversity and plant functional types‘ (pfts) diversity of arid and semi-arid rangelands. we analyzed plant richness and diversity data from 75 sa...

Periphyton grazing by the marine isopod Idothea chelipes was studied by exposing periphyton grown on glass slides to a gradient of grazer densities. An analysis of the algal growth rates and their relationships to grazer density revealed two groups of algae. The unicellular diatoms Licmophora ehrenbergii, Fragilaria tabulata, Navicula spp., Cocconeis costata, and the green alga Ulothrix implexa...

One of the key factors in managing a rangeland is to determine the relative preference of its major plant species by thegrazing livestock. Preference value of each plant species is affected by plant type, companion plants, availability byanimals, phenological stage, climate condition, and the livestock species. We investigated the grazing behaviour of anative goat (Garizi) in the steppe rangela...

Kansas State University Agricultural Experiment Station and Cooperative Extension Service Previously, the release of Conservation Reserve Program (CRP) acres for emergency haying and grazing was a result of drought conditions. Under new program rules, haying and grazing is now allowed on eligible acres regardless of moisture conditions under managed haying and grazing. Managed haying and grazin...

the aim of this study was to provide preliminary quantitative information on selenium and iodine statusof sheep in markazi province, iran. selenium and iodine status of grazing sheep were measured for 57different flocks in 14 regions over one year. the districts were selected to represent major sheep growingareas in the province. blood samples were collected from 2 to 3-year-old ewes during sum...

To mitigate the effects of zoonotic diseases on human and animal populations, it is critical to understand what factors alter transmission dynamics. Here we assess the risk of exposure to lethal concentrations of the anthrax bacterium, Bacillus anthracis, for grazing animals in a natural system over time through different transmission mechanisms. We follow pathogen concentrations at anthrax car...

The diel grazing activity of zooplankton was measured at a single study site in a temperate fjord, Dabob Bay, Washington, USA at several periods during spring, summer and fall of 1979-1981. Pheopigments were used as an indicator of herbivorous zooplankton activity. The downward vertical flux of pheopigment-containing fecal pellets was measured with sediment traps deployed over repetitive 4 h pe...

Warming and grazing significantly affect the structure and function of an alpine meadow ecosystem. Yet, the responses of soil microbes to these disturbances are not well understood. Controlled asymmetrical warming (+1.2/1.7°C during daytime/nighttime) with grazing experiments were conducted to study microbial response to warming, grazing and their interactions. Significant interactive effects o...