Grazing by phagotrophic flagellates and ciliates is a major source of mortality for bacterioplankton in both marine and freshwater systems. Recent studies have demonstrated a positive relationship between clearance rate and prey size for bacterivorous protists. We tested the idea that, by selectively grazing the larger (more actively growing or dividing) cells in a bacterial assemblage, protist...

in order to estimate the relationship between forage quality and preference value of plant species for raini goats(capra aegagrus hircus), a field study was carried out on raini goats’ grazing behavior in some desert habitats.crude protein (as the most important factor affecting forage quality) of all plant species was measured at twophenological stages (spring and summer, 2010) in the dry rang...

The influence of grazing by a mixed assemblage of soil protozoa (seven flagellates and one amoeba) on bacterial community structure was studied in soil microcosms amended with a particulate resource (sterile wheat roots) or a soluble resource (a solution of various organic compounds). Sterilized soil was reinoculated with mixed soil bacteria (obtained by filtering and dilution) or with bacteria...

Seasonal changes in individual clearance rates, selective feeding behavior, and population grazing rates of Keratella cochlearis, Polyarthra vulgaris, Polyarthra dolichoptera, and Bosmina longirostris were investigated in a eutrophic lake using five tracer foods (Aerobacter, Rhodotorula, Chlorella, Chlamydomonas, and Euglena) and by in situ radioisotope techniques. Clearance rates ranged from <...

Grazing and metabolism of Euphausia pacifica in the Yellow Sea were studied from September 2006 to August 2007. Euphausia pacifica is a selective-feeding omnivore and grazing rates among different months were monitored using a Coulter Counter and batch culture feeding experiments. Euphausia pacifica mainly grazed microzooplankton in August and September, which resulted in an increase in chlorop...

Persistence of the opportunistic bacterial pathogen Vibrio cholerae in aquatic environments is the principal cause for seasonal occurrence of cholera epidemics. This causality has been explained by postulating that V. cholerae forms biofilms in association with animate and inanimate surfaces. Alternatively, it has been proposed that bacterial pathogens are an integral part of the natural microb...

grazing management plays an important role in the continuous and economicutilization of pastures. proper grazing management is a main factor for the accumulation ofplant litter which reduces soil erosion and increase the soil permeability to keep moremoisture in the soil. in current study, the effect of three different grazing intensities (low,moderate and high) along with the grazing gradient ...

A study was conducted to evaluate standing crop of forage and cattle diets for a ‘I-pasture high-intensity low-frequency (HILF) grazing system, and a ‘I-pasture short-duration grazing (SDG) system on the same area. A epasture, 3-herd (Merrill) deferred rotation grazing system was sampled as a standard for comparison. Standing crop of forage was highest for the HILF grazing system compared to th...

Many biodiversity experiments have demonstrated that plant diversity can stabilize productivity in experimental grasslands. However, less is known about how diversity-stability relationships are mediated by grazing. Grazing is known for causing species losses, but its effects on plant functional groups (PFGs) composition and species asynchrony, which are closely correlated with ecosystem stabil...