scholarly journals Controls on Nutrient Cycling in Estuarine Mangrove Lake Sediments

2021 ◽  
Vol 9 (6) ◽  
pp. 626
Author(s):  
Michael S. Owens ◽  
Stephen P. Kelly ◽  
Thomas A. Frankovich ◽  
David T. Rudnick ◽  
James W. Fourqurean ◽  
...  
Keyword(s):  
Oxygen Uptake ◽  
Algal Blooms ◽  
Aquatic Macrophyte ◽  
Soluble Reactive Phosphorus ◽  
Florida Bay ◽  
Nitrogen And Phosphorus ◽  
Phosphorus Species ◽  
Gross Photosynthesis ◽  
Sediment Respiration ◽  
Reactive Phosphorus

We estimated the net exchange of nitrogen and phosphorus species using core incubations under light and dark conditions in estuarine lakes that are the aquatic interface between the freshwater Everglades and marine Florida Bay. These lakes and adjacent shallow water Florida Bay environments are sites where the restoration of hydrological flows will likely have the largest impact on salinity. Sediment respiration, measured by oxygen uptake, averaged (±S.D.) −2400 ± 1300, −300 ± 1000, and 1900 ± 1400 μmol m−2 h−1 for dark incubations, light incubations, and gross photosynthesis estimates, respectively, with dark incubations consistent with oxygen uptake measured by microelectrode profiles. Although most fluxes of soluble reactive phosphorus, nitrate, and N2–N were low under both light and dark incubation conditions, we observed a number of very high efflux events of NH4+ during dark incubations. A significant decrease in NH4+flux was observed in the light. The largest differences between light and dark effluxes of NH4+ occurred in lakes during periods of low coverage of the aquatic macrophyte Chara hornemannii Wallman, with NH4+ effluxes > 200 μmol m−2 h−1. Increasing freshwater flow from the Everglades is expected to expand lower salinity environments suitable for Chara, and therefore, diminish the sediment NH4+ effluxes that may fuel algal blooms.

scholarly journals Seasonal Variations of Phosphorus Species in the Overlying and Pore Waters of the Tuohe River, China

2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
Qing Xu ◽  
Xiaoping Yu ◽  
Yafei Guo ◽  
Tianlong Deng ◽  
Yu-Wei Chen ◽  
...  
Keyword(s):  
Seasonal Variations ◽  
Yangtze River ◽  
Algal Bloom ◽  
Soluble Reactive Phosphorus ◽  
Pore Waters ◽  
Phosphorus Species ◽  
Dissolved Phosphorus ◽  
Vertical Distributions ◽  
Reactive Phosphorus ◽  
Main Factor

Overlying sediment and pore waters were collected in summer and winter at upstream (Jintang) and downstream (Neijiang) sites of the Tuohe River, which is one of the five largest tributaries of the Yangtze River in China. Phosphorus species, including soluble reactive phosphorus (SRP), soluble unreactive phosphorus (SUP), and total dissolved phosphorus (TDP), and some diagenetic constituents including dissolved Fe(II), Mn(II), and sulfide in overlying and pore waters, were measured systematically. The seasonal variations and vertical distributions of phosphorus species in overlying and pore waters at both sampling sites were obtained to elucidate some aspects of the transport and transformations of phosphorus. Based on the profiles of pore and overlying waters as well as the TDN/TDP data during an algal bloom in 2007, it was clearly demonstrated that phosphorus was the main factor limiting the phytoplankton growth in the Tuohe River.

Enhanced Activity of Alkaline Phosphatases - Phytoplankton Response to Epilimnetic Phosphorus Depletion

1993 ◽  
Vol 28 (6) ◽  
pp. 15-24 ◽  
Author(s):  
J. Vrba ◽  
J. Komárkova ◽  
V. Vyhnálek
Keyword(s):  
Algal Blooms ◽  
Phytoplankton Community ◽  
Phytoplankton Bloom ◽  
Soluble Reactive Phosphorus ◽  
High Input ◽  
Alkaline Phosphatases ◽  
Spring Phytoplankton Bloom ◽  
Reactive Phosphorus ◽  
Longitudinal Sampling ◽  
Phosphorus Depletion

The stratified, eutrophic ůímov Reservoir (South Bohemia) receives a considerable input of phosphorus. However, phytoplankton development in the epilimnion has often been P-limited (<5 µg.1−1 of soluble reactive phosphorus) during spring and summer when algal maxima are observed. Alkaline phosphatase activity (APA) was measured in the epilimnion (0-2 m) using a fluorimetric method. The seasonal course of APA (range 6.7-726.7 nmol.1−1.h−1) roughly followed that of chlorophyll a (r2 = 0.45) in 1990. During algal blooms, a significant percentage of total APA was found in the 2.5-100 µ µm fraction containing most of the algae. Very similar relationships were found by a longitudinal sampling of the reservoir epilimnion during the spring phytoplankton bloom in 1991, despite high P concentrations in the reservoir's tributary. Hence, phytoplankton can be P-limited in the epilimnion, even in a eutrophic reservoir with a high input of P. This study shows that the phytoplankton community might adapt to phosphorus depletion by changing species composition and/or by increasing APA.

scholarly journals Long-Term Study of Soluble Reactive Phosphorus Concentration in Fall Creek and Comparison to Northeastern Tributaries of Cayuga Lake, NY: Implications for Watershed Monitoring and Management

Water ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 2075 ◽  
Author(s):  
O’Leary ◽  
Johnston ◽  
Gardner ◽  
Penningroth ◽  
Bouldin
Keyword(s):  
Flow Rate ◽  
Algal Blooms ◽  
Soluble Reactive Phosphorus ◽  
Phosphorus Concentration ◽  
Term Study ◽  
Long Term Study ◽  
Cayuga Lake ◽  
Significant Difference ◽  
Reactive Phosphorus

This study focuses on soluble reactive phosphorus (SRP), a key driver of eutrophication worldwide and a potential contributor to the emerging global environmental problem of harmful algal blooms (HABs). Two studies of tributary SRP concentrations were undertaken in sub-watersheds of Cayuga Lake, NY, the subject of a total maximum daily load (TMDL) development process, due to phosphorus impairment of its southern shelf. The long-term study compared SRP concentration in Fall Creek in the 1970s with that in the first decade of the 2000s, thus spanning a period of change in phosphorus sources, as well as in regional climate. The spatial study used data collected between 2009 and 2018 and compared SRP concentrations in Fall Creek to levels in northeastern tributaries that flow into the lake close to areas where HABs have been problematic. SRP was measured using standard procedures. Flow-weighted mean SRP concentration ranged between 15.0 µg/L and 30.0 µg/L in all years studied in both the 1970s and 2000s, with the exception of 2010. Annual discharge in Fall Creek showed no trend between 1970 and 2018, but a higher proportion of high streamflow samples was captured in the 2000s compared to the 1970s, which resulted in proportionally increased SRP concentration in the latter time period. There was no significant difference in the SRP concentration—flow rate relationship between the two time periods. Adjusted for flow rate, SRP concentrations in Fall Creek have not changed over many decades. Increasing phosphorus contributions from growing population and urbanization since the 1970s may have been counterbalanced by improvements in wastewater treatment and agricultural practices. Mean SRP concentration in northeastern tributaries was significantly (p < 0.001) higher than in Fall Creek, likely reflecting more intense agricultural use and higher septic system density in the watersheds of the former. This finding justifies continued monitoring of minor northern tributaries. Future monitoring must emphasize the capture of high flow conditions. Historical stability and highly variable hydrology will slow the watershed response to management and confound the ability to detect changes attributable to decreased phosphorus inputs. Large scale monitoring on decadal timescales will be necessary to facilitate watershed management.

Prescribed fire, soils, and stream water chemistry in a watershed in the Lake Tahoe Basin, California

2004 ◽  
Vol 13 (1) ◽  
pp. 27 ◽  
Author(s):  
Scott L. Stephens ◽  
Thomas Meixner ◽  
Mark Poth ◽  
Bruce McGurk ◽  
Dale Payne
Keyword(s):  
Prescribed Fire ◽  
Stream Water ◽  
Soluble Reactive Phosphorus ◽  
Lake Tahoe ◽  
Prescribed Fires ◽  
Lake Tahoe Basin ◽  
Nitrogen And Phosphorus ◽  
Stream Water Chemistry ◽  
Tahoe Basin ◽  
Reactive Phosphorus

Before Euro-American settlement fire was a common process in the forests of the Lake Tahoe Basin. The combination of drought, fire suppression, and past harvesting has produced ecosystems that are susceptible to high-severity wildfires. Consequently, a program of prescribed fire has been recommended but there is incomplete understanding of the ecological effects of fuels treatments, especially with regard to how treatments will affect the flow of nutrients to Lake Tahoe. Nitrogen and phosphorus are the most important nutrients affecting algal growth, and thus lake clarity. Existing data demonstrate a long-term shift from a co-limitation by both nitrogen and phosphorus to phosphorus limitation. Two high-consumption, moderate-intensity prescribed fires were conducted to determine their effects on soil and stream water chemistry. Stream water calcium concentrations increased in burned watersheds whereas soluble reactive phosphorus concentrations were not significantly different. Prescribed fires released calcium and raised soil pH and this may have resulted in the incorporation of phosphorus into insoluble forms. Stream monitoring data indicates water quality effects last for ~3 months. Prescribed fires did not significantly increase the amount of soluble reactive phosphorus in stream waters. However, additional research is needed to determine if prescribed fire increases erosion or movement of particulate P, particularly in areas with steep slopes.

Effects of tributary inputs on nutrient export from the Mississippi and Atchafalaya Rivers to the Gulf of Mexico

2010 ◽  
Vol 61 (9) ◽  
pp. 1029 ◽  
Author(s):  
Shuiwang Duan ◽  
Thomas S. Bianchi ◽  
Peter H. Santschi ◽  
Rainer M. W. Amon
Keyword(s):  
Gulf Of Mexico ◽  
Mississippi River ◽  
Soluble Reactive Phosphorus ◽  
Suspended Sediments ◽  
River System ◽  
Nitrogen And Phosphorus ◽  
Channel Processes ◽  
Particulate Nitrogen ◽  
Nutrient Mass Balance ◽  
Reactive Phosphorus

In order to better understand the seasonal patterns of nutrient loadings from the Mississippi River to the Gulf of Mexico, nutrient mass balance analyses were performed for the Mississippi River system to separate the effects of primary tributary inputs from in-channel processes. Our results showed that seasonal changes in dissolved inorganic nutrients resulted from conservative mixing of primary tributaries. Maximal values of nitrate plus nitrite (NO3+2) and soluble reactive phosphorus (SRP) fluxes during May through July were largely attributed to inputs from the upper Mississippi River (UMR), which was highest in NO3+2 and SRP levels and contributed more water during this period. Mass balances also showed net losses of particulate nitrogen and phosphorus (29% and 18%, respectively), with the highest values occurring during the falling stage. We speculate that one possible reason was retention of coarse suspended sediments that were mainly derived from the Missouri River. The loss of dissolved organic nitrogen and phosphorus was also apparent (∼12% and 20%, respectively), and the largest loss occurred during summer. This study highlights the importance of divergent processes in controlling different forms of nutrients in large rivers.

scholarly journals Nutrient concentrations and fluxes for podzolic and gley soils at Plynlimon, mid-Wales: implications for modelling inorganic nitrogen and phosphorus in upland UK environments

2002 ◽  
Vol 6 (3) ◽  
pp. 403-420
Author(s):  
C. Neal
Keyword(s):  
Inorganic Nitrogen ◽  
Soluble Reactive Phosphorus ◽  
Sitka Spruce ◽  
Nutrient Concentrations ◽  
Nitrogen And Phosphorus ◽  
Podzolic Soils ◽  
Forestry Management ◽  
Order Of Magnitude ◽  
Reactive Phosphorus ◽  
Stream Nitrate

Abstract. The effect of felling on stream nitrate, ammonium and soluble reactive phosphate (SRP) concentrations is examined for acidic and acid sensitive Sitka Spruce afforested catchments with podzolic and gley soils in mid-Wales. For the streams draining the felled podzolic areas, the concentrations of nitrate can be up to an order of magnitude higher than pre-fell values and post-fell concentrations can even be lower than the pre-fell values. Felling for the podzolic soils barely leads to any changes in ammonium or SRP concentration. For the gley soils, felling results in an order of magnitude increase in nitrate, ammonium and SRP for a small drainage ditch, but the pulse is much reduced before it reaches the main Nant Tanllwyth channel. Rather, within-catchment and within-stream processes not only imbibe nitrate, ammonium and SRP fluxes generated, but in the case of nitrate, concentrations with- and post-felling are lower than pre-felling concentrations. The flux changes involved are described in terms of (a) input-output relationships and (b) "felling disruption" and "felling recovery responses". The findings are linked to issues of hydrobiological controls and forestry management. Keywords: Plynlimon, Hafren, Hore, streams, nitrate, ammonium, SRP, phosphorus, soluble reactive phosphorus, phosphate, orthophosphate, Sitka spruce, forestry, felling, podzol, gley

A laboratory culture system for pathological and physiological studies of rooted aquatic plants

1984 ◽  
Vol 62 (11) ◽  
pp. 2290-2296 ◽  
Author(s):  
J. P. Hoffmann ◽  
J. A. Colman ◽  
K. M. Kutchera ◽  
E. V. Nordheim ◽  
J. H. Andrews
Keyword(s):  
Growth Rate ◽  
Myriophyllum Spicatum ◽  
Soluble Reactive Phosphorus ◽  
Growth Period ◽  
Dry Weight ◽  
Laboratory Culture ◽  
Ammonium Nitrogen ◽  
Nitrogen And Phosphorus ◽  
Mineral Salts ◽  
Reactive Phosphorus

A biphasic system was designed for growing rooted Eurasian water milfoil, Myriophyllum spicatum L., to avoid artificial characteristics of flask culture. Aquaria (21 L) containing undergravel filters, air-lift pumps, 50-W heaters, and Plexiglas lids were sterilized in 70% ethanol and assembled aseptically. Plant shoots were rooted separately in polypropylene cups containing 60 g of artificial sediment approximating natural marl. The sediment provided over 90% of the nitrogen and phosphorus in the plants after 22 days growth. Plants were immersed in a mineral-salts medium with levels of nitrogen and phosphorus comparable with lake concentrations. Aeration was at 0.15 L ∙ min−1 and ranges of temperature and light intensity were from 17 to 32 °C and 30 to 250 μE ∙ m−2 ∙ s−1, respectively. The peak photosynthetic rate was 14 mg O2 ∙ g dry weight−1 ∙ h−1. The maximum specific growth rate, 0.14 mg ∙ mg−1 ∙ day−1, occurred at 27 °C and 250 μE ∙ m−2 ∙ s−1 and lasted for about 3 weeks before light became limiting. Bacterial density, ammonium nitrogen, soluble reactive phosphorus, and total phosphorus exhibited rapid changes during the first 12 days of the growth period, after which fluctuations diminished. The between-aquaria variance in shoot growth rate was insignificant (P > 0.70). When inorganic carbon in the liquid medium and phosphorus in the sediment were lowered from 2.86 to 1.14 mmol C ∙ L−1 and from 0.7 to 0.2 mg P ∙ g dry weight−1, milfoil growth was reduced by 47 and 74%, respectively. Control of the physiochemical environment, small variability, and high reproducibility make this a sensitive system for discerning various treatment effects, including those of pathogens.

scholarly journals Effects of Lanthanum Modified Bentonite and Polyaluminium Chloride on the Environmental Variables in the Water and Sediment Phosphorus Form in Lake Yanglan, China

Water ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 1947
Author(s):  
Ling Su ◽  
Chen Zhong ◽  
Lei Gan ◽  
Xiaolin He ◽  
Jinlei Yu ◽  
...  
Keyword(s):  
Suspended Solids ◽  
Soluble Reactive Phosphorus ◽  
Particulate Phosphorus ◽  
Modified Bentonite ◽  
Combined Application ◽  
Water And Sediment ◽  
Phosphorus Form ◽  
Labile P ◽  
Reactive Phosphorus ◽  
Polyaluminium Chloride

The application of lanthanum modified bentonite (Phoslock®) and polyaluminium chloride (PAC) is popular in the restoration of European temperate lakes; however, the effects of the application on the concentrations of phosphorus (P) in both the water and the sediments have been poorly evaluated to date. We studied the effects of the application of Phoslock® + PAC on the concentrations of total phosphorus (TP), particulate phosphorus (PP), soluble reactive phosphorus (SRP), total suspended solids (TSS) and chlorophyll a (Chla) in the water, and different P forms in the sediments, in an isolated part of Lake Yanglan. The results showed that the concentrations of TP, PP, SRP, TSS and Chla decreased significantly after the addition of Phoslock® + PAC. Moreover, the concentrations of labile-P, reductant-soluble-P and organic-P in the sediments were also significantly decreased after the Phoslock® + PAC application. However, the concentrations of both the stable apatite-P and residual-P in the sediments after application of Phoslock® + PAC were much higher than the pre-addition values, while the concentrations of metal-oxide-P did not differ significantly between the pre- and post- application conditions. Our findings imply that the combined application of Phoslock® and PAC can be used in the restoration of subtropical shallow lakes, to reduce the concentrations of P in the water and suppress the release of P from the sediments.

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