During the past few winters several nomadic areas in the Tibet Autonomous Region (TAR) of the People's Republic of China have been greatly affected by unusually heavy snowfall. Losses in Nacqu Prefecture alone were estimated ar 1.03 million animals or about 15 % of the Prefecture's totallivestock population (MILLER, 1998). Thus far there have only been theories about the true causes of these ca...

A modified litter-bag method was used to measure plant fineroot decomposition in relation to biomass quality in a mixedgrass prairie. Measurements were made during three years on moderately and heavily grazed pastures that had been under cattle grazing for 17 years prior to sampling. Although we found no significant difference in initial fine-root litter quality between grazing treatments, nitr...

Pastures located on southern Iowa cow/calf farms, from 8 to 125 ha in size, were used to evaluate the effects of microclimate, shade, botanical composition, and other pasture characteristics influencing the temporal/ spatial distribution of cattle within and outside streamside zones of pastures. Cows were Angus and Angus-cross on 4 of the farms, and Mexican Corriente on the remaining farm. Duri...

Canada thistle remains the most common and troublesome weed of pastures, roadsides and other areas of low-maintenance sods. Even though numerous herbicides have excellent activity on Canada thistle, the extensive root system of this species complicates longterm management. This paper will discuss recent research conducted in Alberta, Canada investigating the role of pasture fertilization in Can...

Feedbacks within ecosystems can lead to internal reinforcement of the current state providing ecosystem resilience. Often, multiple biotic interactions across trophic levels play a role in such feedbacks, yet these are generally studied independently, obscuring relative importance among different factors. We look at various potential feedbacks intact and degraded mesic forests on Hawai?i Island...

Some ewes grazing oestrogenic pasture consistently produce viable offspring and are therefore considered to be resistant to Clover Disease. In a search for factors associated with this resistance Obst, Seamark and McGowan (1971) reported a significant association between ewe fertility and haemoglobin type (Hb) in a small flock of Merino ewes grazing Yarloop clover pastures. Low fertility and hi...

Most Australian soils are derived from parent material which is low in phosphorus. Soils of low phosphorus status support early maturing, grass dominant pastures with a short summer growth period and hence lengthy period of senescence. Phosphorus in these grasses may be as low as 0.02 g P/100 g OM during senescence (Robinson and Sageman 1967) and may only reach 0.15 g.P/lOO g OM during active g...

A Z-R relation is derived using a data set which consists of nine rain events selected from Singapore’s drop size distribution. Rain events are separated into convective and stratiform types of rain using two methods: the Gamache-Houze method, a simple threshold technique, and the Atlas-Ulbrich method. In the Atlas-Ulbrich method, the variability of the rain integral parameters R, Z, Nw, D0 and...

Gravity ventilators rely simply on air buoyancy to extract air and are widely used to exhaust air contaminants and heat from workplaces using minimal energy. They are designed to maximize the exhaust flow rate, but the rain penetration sometimes causes malfunctioning. In this study, the characteristics of rain penetration through a ventilator were examined as a preliminary study to develop a ve...

Though warm rain from low-level liquid clouds contributes significantly to the global precipitation and water cycle, it has been missed or underestimated by satellite remote sensing techniques. IR techniques miss all warm rain because they rely on cloud top temperature. Over land, passive microwave techniques miss all warm rain because they rely on ice scattering at high frequency channel. Over...