The study reported herein was conducted to determine and compare the nonphytate P, digestible P, and retainable P contents of corn and canola meal for broiler chickens. Four semipurified diets were formulated from each of ingredient to contain graded concentrations of nonphytate P. The experiment was conducted as a randomized complete block design with 4 weight blocks of 8 cages each (6 birds p...

Microalgae can be used for the treatment of municipal wastewater. The application of microalgal biofilms in wastewater treatment systems seems attractive, being able to remove nitrogen, phosphorus and COD from wastewater at a short hydraulic retention time. This study therefore investigates the area requirement, achieved effluent concentrations and biomass production of a hypothetical large-sca...

Although the process of eutrophication is reasonably well understood in lakes, there is currently no conceptual understanding of how eutrophication develops in rivers. This issue is addressed here. A review of the main processes controlling the development of eutrophication in lakes has been carried out as a precursor to considering the effect in rivers. The importance of hydraulic flushing in ...

Inputs of available nitrogen (N) to ecosystems have grown over the recent past. There is limited general understanding of how increased N inputs affect the cycling and retention of other potentially limiting nutrients. Using a plant-soil nutrient model, and by explicitly coupling N and phosphorus (P) in plant biomass, we examine the impact of increasing N supply on the ecosystem cycling and ret...

Nutrient availability regulates the responses of high-latitude ecosystems to climate change but nitrogen, phosphorus and sulfur biogeochemistry, especially, phosphorus and sulfur cycles, are poorly understood in Alpine tundra ecosystem. This study examines the cycling of nutrients in a 302-year-old Alpine tundra ecosystem in which litter has accumulated through compartment methods. Samples of t...

The P-RoC process – the phosphorus recovery straight from the aqueous phase by crystallisation of calcium phosphate – was developed in order to simultaneously remove and recover phosphorus from municipal wasteand industrial process waters by applying calcium silicate hydrate (CSH) compounds or synthesised tobermorite pellets as crystallisation seed materials. At first, the experiments were perf...

Enzyme and or hormone actions have not been shown to be consistently changed by consuming a low-magnesium diet similar to one that may occur in the general population. Thus, a human metabolic study was performed to determine whether deficient intakes of magnesium similar to those that occur naturally have pathophysiological effects through altering calcium retention and the metabolism of other ...

Shirasuboshi (boiled and semi-dried whitebait) is a processed fish food that contains abundant calcium. It is eaten whole and commonly consumed in Japan. In this study, the effect of sudachi (Citrus sudachi) juice on calcium, magnesium and phosphorus bioavailability, and bone metabolism in rats was examined. After 14 d of diets low in calcium and phosphorus, male Sprague-Dawley rats were fed sh...

Magnesium tolerance tests were conducted in five female goats to determine the effect of increasing dietary potassium level from .9% (basal diet) to 4.0% (high-K diet) on an animal's capacity for disposing of an intravenous load of magnesium. Both diets contained about .07% magnesium, .91% calcium and .56% phosphorus. Following intravenous injections of magnesium acetate (.5 mEq of Mg/kg body w...

During the 20(th) century, seawater temperatures have significantly increased, leading to profound alterations in biogeochemical cycles and ecosystem processes. Elevated temperatures have also caused massive bleaching (symbiont/pigment loss) of autotrophic symbioses, such as in coral-dinoflagellate association. As symbionts provide most nutrients to the host, their expulsion during bleaching in...