citric acid has been reported to increase utilization efficiency of dietary phytate-bound phosphorus and protein. objective of this study was to determine the effects of citric acid on growth performance and nutrient retention of broiler chickens fed diets having two levels of non-phytate phosphorus and rice bran. giving a completely randomize design in 2 × 2 × 2 factorial arrangement, 144 broi...

We studied nutrient uptake in relation to water chemistry, stream hydrodynamics, and ecosystem metabolism in two eutrophic lowland streams located near Berlin, Germany. Ambient nutrient uptake rates ranged from 0.180 to 12.880 g NO3-N m22 d21, from 0.035 to 0.517 g NH4-N m22 d21, and from 0.017 to 0.750 g PO4-P m22 d21. Temporal and spatial variability in nutrient uptake rates within single str...

In this study, we evaluated the efficiency of two types of biomass residues (fermentation residues from a bioethanol process, FB; brown mill residues from a papermaking process, BM) as amendments for a sandy soil. The characteristics of these residues including specific surface areas, morphologies and nutrient sorption capacity were measured. The effects of biorefinery residues on water and nut...

The objectives of this study were 1) to compare Sonoran Desert streams with other streams in terms of retention efficiency of nitrate; 2) to examine the effects of a flood on nitrate retention and to determine which factors control nitrate retention in the surface stream subsystem in Sycamore Creek, Arizona; and 3) to compare the short-term nutrient addition technique with computations based up...

Extensive network of tile drains present in the Midwest USA accelerate losses of nutrients to receiving ditches, rivers and eventually to the Gulf of Mexico. Nutrient inputs from agricultural watersheds and their role in affecting water quality have received increased attention recently; however, benthic sediment-nutrient interactions in tile-fed drainage ditches is still a matter of active res...

We used mass load budgets, transient storage modeling, and nutrient spiraling metrics to characterize nitrate (NO), ammonium (NH), and inorganic phosphorus (SRP) demand in seven agricultural streams across the United States and to identify in-stream services that may control these conditions. Retention of one or all nutrients was observed in all but one stream, but demand for all nutrients was ...

Various features of a landscape contribute to the regulating ecosystem service of reducing waterborne pollutant loading to downstream environments. At local scales, wetlands have been shown to be effective in retaining pollutants. Here, we investigate the landscape-scale contribution to pollutant retention provided by multiple wetlands. We develop a general analytical model which shows that the...

In northeastern Austria, marshlands have been turned into the most productive arable land of the country. As a result, most headwater streams show structurally degraded channels, lacking riparian buff er zones, which are heavily loaded with nutrients from the surrounding crop fi elds. Th e present study examines whether longitudinally restricted riparian forest buff ers can enhance the in-strea...

From hatch to 18 d of age broilers were fed starter diets with (0.9 kg/ton) or without direct fed microbial (DFM). At 18 d, birds were weighed and, within DFM treatment (trt), randomly assigned to battery pens. In Exp 1, a 2 x 2 factorial arrangement of nutrient density [control (C, 19.3% protein (CP), 0.84%, Ca 0.37% nonphytin P (nPP); and 17.1% CP, 0.8% Ca, and 0.3% nPP in the grower (Gr) and...