On a global scale, reservoirs have been identified as the most significant sink of suspended sediment (TSS), carbon (C), nitrogen (N), and phosphorus (P) in inland waters, reducing nutrient fluxes from upland to downstream ecosystems and coastal regions (Cole et al. 2007; Friedl and Wüest 2002; Bosch and Allan 2008; Seitzinger et al. …

Nitrogen, phosphorus, and sediment loads show significant variations from year to year, and these variations are mostly related to rainfall, runoff, and streamflow conditions during the year. Over long time scales, however, the amount of nutrients delivered to the bay are expected to decline as management and restoration activities …

A year-long field investigation was carried out in the most heavily polluted bay of Lake Chaohu to assess the temporal exchanges of ammonium nitrogen and soluble reactive phosphorus (SRP) across the sediment–water interface (SWI) and to provide remediation advises.Results showed that the monthly average fluxes of and SRP were 31.38 and …

Concentrations of nitrogen, phosphorus, and suspended sediment are measured at the U.S. Geological Survey streamgage at Conowingo Dam at the downstream end of the Susquehanna River Basin in Maryland, where the river flows into the Chesapeake Bay. During the period September 7–15, 2011, in the aftermath of Tropical …

Nitrogen and P fertilizer prices increased in this period, especially between 2007 and 2008 (Supplemental Fig. S8). This may have caused farmers to use more manure in place of synthetic fertilizers, potentially contributing to increased NH 4 concentrations. In addition, the number of hogs increased from 2002 to 2011, although we do not have ...

The study of the ecological risk assessment of nitrogen and phosphorus in sediments is important to understand the environmental quality of water body in the basin. In this study, taking the ...

The effects of nitrogen and phosphorus were relatively weak compared to sediment. Several complex and unpredictable 2-way or 3-way interactions among stressors were observed. While sediment addition generally reduced total abundance at high levels, this decrease was amplified by P enrichment at low sediment, whereas the opposite …

Figure ES-1. A nitrogen, phosphorus and sediment TMDL has been developed for each of the 92 Chesapeake Bay segment watersheds. Additionally, President Obama issued Executive Order 13508 on May 12, 2009, which directed the federal government to lead a renewed effort to restore and protect the Chesapeake Bay and its

Consequently, it will be necessary to investigate the total nitrogen (TN) and phosphorus (TP) contents in the sediments, assess the risks of these nutrients to the …

Nitrogen, phosphorus, and suspended-sediment loads, and changes in loads, in major rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the Chesapeake Bay Nontidal Network (NTN) stations stations for the period 1985 through 2020. Nutrient and suspended-sediment loads and changes in …

SPAtially Referenced Regression On Watershed attributes (SPARROW) models were developed to quantify and improve the understanding of the sources, fate, and transport of nitrogen, phosphorus, and suspended sediment in the northeastern United States. Excessive nutrients and suspended sediment from upland watersheds and tributary …

Excess nutrients (nitrogen and phosphorus) and sediment in urban runoff are known to impair runoff water quality as it moves downstream, and degrade aquatic habitats in downstream water bodies (Lintern et al., 2020). Estimating these pollutant loads from developed watersheds is vitally important as one of the key tools for reducing …

Here we show that the average concentrations of nitrogen and phosphorus in lake sediments have increased by 267% and 202%, respectively since 1850. In the model projections, 2030–2100, the nitrogen concentrations in the studied lakes in China may decrease, for example, by 87% in the southern districts and by 19% in the …

The phosphorus cycle is slow. Most phosphorus in nature exists in the form of phosphate ion— PO 4 3 −. Phosphorus is often the limiting nutrient, or nutrient that is most scarce and thus limits growth, in aquatic ecosystems. When nitrogen and phosphorus from fertilizer are carried in runoff to lakes and oceans, they can cause …

This is why nutrient and sediment loads from these nine stations are used to model the total loads to the Chesapeake Bay. Most Recent Data Highlights. The nontidal network mapper is an interactive web page that summarizes the latest findings for nitrogen, phosphorus and suspended-sediment trends. Click the image below to explore the …

Spatially Referenced Regression On Watershed attributes (SPARROW) models were applied to describe and estimate mean-annual streamflow and transport of total nitrogen (TN), total phosphorus (TP), and suspended sediment (SS) in streams and delivered to coastal waters of the southeastern United States on the basis of inputs and management …

The model structure for SFM involves three processes: (1) the sediment receives depositional fluxes of particulate organic carbon and nitrogen, as well as biogenic and inorganic phosphorus and silica, from the overlying water, (2) the decomposition of particulate matter produces soluble intermediates that are quantified as diagenesis …

Total Kjeldahl nitrogen, total phosphorus and suspended sediment mostly trended downward. Overall, the trends in various forms of nitrogen were observed at most sites irrespective of the degree of development and indicate a change in ecological conditions is affecting the nitrogen cycle throughout the watershed, most likely …

High internal sediment loadings increase nitrogen (N) and phosphorus (P) concentrations in the water and thereby accelerate eutrophication and the growth of …

Nitrogen, phosphorus, and suspended-sediment loads, and changes in loads, in major rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the Chesapeake Bay River Input Monitoring (RIM) Network stations for the period 1985 through 2021. Nutrient and suspended-sediment loads and changes in …

To assess the sediment stocks of each element (C stock, Nstock, and P stock ), particulate organic carbon [POC % dry weight (%. dw)], total nitrogen (TN % dw), and total phosphorus (TP % dw ...

Nitrogen (N) and phosphorus (P), as major nutrients for aquatic ecology, are always important factors for lake eutrophication. It is generally recognized that organic N and P become available to aquatic organisms only after they have been mineralized (Acquaye 1963).Since sediments which were thought to play a key role in releasing of N …

We used the Soil and Water Assessment Tool (SWAT) with various spatiotemporal data to quantify the contributions of climate and land use changes to runoff, sediment, nitrogen (N) and phosphorus (P) losses in …

Nitrogen, phosphorus, and sediment load reductions were positively correlated with the reservoir water temperature and HRT, and negatively correlated with water inflow to the reservoir and reservoir water volume. This would suggest that the removal efficiency of the reservoir would be highest during summer and early fall when …

As the largest and most productive estuary in North America, Chesapeake Bay is a vital ecological and economic resource. In recent decades, however, the bay and its tributaries have been degraded by excessive inputs of nutrients (nitrogen and phosphorus) and sediment from contributing watersheds, and in 1998, the Chesapeake …

Here we show that the average concentrations of nitrogen and phosphorus in lake sediments have increased by 267% and 202%, respectively since 1850. In the model projections, 2030–2100, the nitrogen concentrations in the studied lakes in China may decrease, for example, by 87% in the southern districts and by 19% in the northern districts.

Phosphate-containing ocean sediments slowly move to land by the uplifting of areas of the earth's surface. Excess phosphorus and nitrogen in the ecosystem leads to the …

The migrations of nitrogen and phosphorus in lake sediment are often driven by various factors, while migration after anthropogenic disturbance with microorganism forces has rarely been discussed in previous work. Therefore, this study aimed to investigate the migrations of nitrogen and phosphorus in lake sediments with …

Source of sediments and depositional processes of surface sediments along the Prydz Bay were investigated through grain size, organic carbon, nitrogen, phosphorus, calcium carbonate and metal ...

The spatial pattern of sediment nitrogen was determined by wind-induced hydrodynamics. • The spatial pattern of sediment phosphorus was determined by …

Sediments are important reservoirs of nutrient salts such as nitrogen and phosphorus in lakes, which slow the process of eutrophication by absorbing contaminants in large quantities (Gunnars and Blomqvist 1997).As a consequence, to some extent, sediment is a sink for pollutants (Xing et al. 2021).However, when the environment …

A good correlation between nitrogen and phosphorus in the sediments often indicates a common source or identical production pathway. However, in the present study, such correlations between nitrogen and phosphorus were observed only in the east coast mangrove ecosystems (R 2 = 0.4, p < 0.0001, n = 32). These results indicated …