the parameters used to determine the trophic state of a water body are: total phosphorus (tp),transparency (secchi disk depth) and chlorophyll a. however, these parameters show strong seasonalfluctuations which may hinder the estimation of trophic state. some authors have proposed that sediments be used as an additional tool to evaluate the trophic state of a water body. the aim of this study w...

Abstraet--A budget model is developed to predict the long-term response of a lake to changes in its phosphorus loading. This model computes total phosphorus and hypolimnetic oxygen concentrations, taking sediment-water interactions into account. The lake is treated as two segments: the water and a surface sediment layer. A total phosphorus budget for the water accounts for inputs due to externa...

• Median total phosphorus concentrations for the period 1984-93 were less than 0.1 milligrams per liter at 65 of the 83 stations evaluated in the study unit. • Highest total phosphorus concentrations were in the Hiwassee River Basin (near 2.0 milligrams per liter) and at West Chickamauga Creek near Chattanooga (1.45 milligrams per liter). • Total phosphorus concentrations have not significantly...

BACKGROUND External nutrient discharges have caused eutrophication in many estuaries and coastal seas such as the Baltic Sea. The sedimented nutrients can affect bacterial communities which, in turn, are widely believed to contribute to release of nutrients such as phosphorus from the sediment. METHODS We investigated relationships between bacterial communities and chemical forms of phosphoru...

The transport characteristics of phosphorus in soil and the assessment of its environmental risk have become hot topics in the environmental and agricultural fields. The Sanjiang Plain is an important grain production base in China, and it is characterised by serious land use change caused by large-scale agricultural exploitation. Agricultural inputs and tillage management have destroyed the so...

Attribution of the causes of trends in nutrient loading is often limited to correlation, qualitative reasoning, or references to the work of others. This paper represents efforts to improve causal attribution of water-quality changes. The Red River of the North basin provides a regional test case because of international interest in the reduction of total phosphorus loads and the availability o...

Langenfeld, M. G. (University of South Dakota, Vermillion) and P. F. Smith. Phosphorus distribution in pleuropneumonia-like and L-type organisms. J. Bacteriol. 86:1216-1219. 1963.-Sterol-requiring and sterol-nonrequiring pleuropneumonia-like organisms, salt-requiring and salt-nonrequiring L forms, and their parent bacteria, were analyzed for total, acid-soluble, lipid, and nucleic acid phosphor...