A field experiment was carried out to assess biomass and nitrogen status inMediterranean pastures by means of hyperspectral high resolution field radiometric data. Spectral and agronomic measurements were collected at three different pasture growth stages and in grazed–ungrazed plots distributed over an area of 14 ha. Reflectance-based vegetation indices such as simple ratio indices (SR[i,j]) a...

It has often been stated or implied that grazing is an important factor in the land degradation process, a suggestion supported by various research projects, and this study investigated the effect of livestock grazing on stem height, crowncover, production, basal diameter, stem biomass, litter, leaf-stem index (leaf to stem weight) , root diameter and weight and seed production per individual o...

recent attitude of vegetation assessors is using of new ecologic approaches to evaluate and analyse the complex rangeland ecosystems. plant diversity is the most important indices to assess the ecological changes of rangelands. in order to survey of plant indices of rangelands, two exclosure areas (long-term and mid-term) and a grazing area in rangelands of javaherdeh (ramsar, iran) were select...

Pale-headed Brush-finch Atlapetes pallidiceps is a restricted-range species that is threatened with extinction due to habitat loss. The total population of 60–80 individuals achieved a reproductive output of only 0.74 young per breeding pair in 2002. Brood parasitism by Shiny Cowbird Molothrus bonariensis was a major factor reducing breeding success, affecting 38.5% of broods. Parasitism rates ...

The objective of these studies was to compare preference for leafy spurge (Euphorbiu es& L.) by sheep and goats. Study 1 was a choice test that paired leafy spurge with either arrowleaf balsamroot (Balsamorhiza sagittata (Pursh)Nutt.) or crested wheatgrass (Agropyron cristatum (L.)Gaertn.) for a 30 minute feeding period. Study 2 consisted of 3 grazing trials on spurgeinfested pastures. Differen...

Ungrazed tallgrass prairie plots in the Kansas Flint Hills have been burned annually at 4 different dates since 1928. Time of burning markedly altered the physiognomy and was the crucial factor effecting vegetation change. Late-spring burning, coinciding with emergence of the warm-season perennial grasses, increased grass production and favored Andropogon gerardii and Sorghastrum nutans. Burnin...

In the present study, we aim to analyze the effect of grazing, precipitation and temperature on plant species dynamics in the typical steppe of Inner Mongolia, P.R. China. By uncoupling biotic and abiotic factors, we provide essential information on the main drivers determining species composition and species diversity. Effects of grazing by sheep were studied in a controlled experiment along a...

The objective of the present experiment was to describe the sward canopy structures of 3 different wheat (Triticum aestivum L.) pastures and relate them to short-term herbage intake rate and foraging dynamics by steers. Pastures were sampled for leaf and stem fractions at the bottom, middle, and top canopy strata. Sward surface heights and tiller and bulk densities were measured. Herbage was se...

Abstract Recovery of green turtles ( Chelonia mydas ), mega‐herbivores that consume seagrasses, is resulting in dramatic ecosystem‐wide changes as meadows are returned to a natural grazed state. The turtle grazing strategy, with long‐term cultivation and high foraging site fidelity, distinct from other terrestrial aquatic may affect seagrass compensatory growth responses. Identifying the mechan...