Photochemical mineralization of dissolved organic nitrogen to ammonia in prairie lakes

  title={Photochemical mineralization of dissolved organic nitrogen to ammonia in prairie lakes},
  author={S Jeff and Kristine Hunter and David M. Vandergucht and Jeff Hudson},
We examined the rate of photoammonification in 16 lakes from Saskatchewan, Canada. Lakes were selected to encompass a broad range in dissolved organic nitrogen (DON) (269–1,435 μg l−1). Lake filtrate (<0.2 μm) was exposed to artificial solar radiation for 4 h. Rates of photoammonification were significant in 7 of the 16 study lakes. Ammonia (NH3) concentrations increased 0.84–2.85 μg l−1 over control values. This is a 4–92% increase in NH3 concentration and a conversion of 0.18–0.3% of the DON… 

Size Fractionation of Dissolved Organic Nitrogen in Peatland Fluvial Systems.

This study suggests that current understanding of inorganic N as the sole source of bioavailable N with eutrophic significance in upland freshwaters requires a reappraisal and Evaluation of ecosystem response to increased loading of N needs to include a consideration of LMW DON.

Dissolved organic nitrogen (DON) in seventeen shallow lakes of Eastern China

The terrestrial export of dissolved organic nitrogen (DON) is associated with climate, geography and land use, and thus is influenced by geo-climatic variability, human interference, the farmland and

Photoproduction of dissolved organic carbon and inorganic nutrients from resuspended lake sediments

Results demonstrated that the photoproduction flux of NH4+ and NOx− accounts for 12.3 and 6.5 % of wet deposition, respectively, which suggest that thephotodissolution of suspended sediment could be a potential source of DOC and dissolved nutrients in shallow water ecosystems.

Characteristics of Dissolved Organic Matter and Its Role in Lake Eutrophication at the Early Stage of Algal Blooms—A Case Study of Lake Taihu, China

Decaying algal blooms in eutrophic lakes can introduce organic matter into the water and change nutrient concentrations in the water column. The spatial distribution and composition characteristics,



Photochemical production of ammonium in the oligotrophic Cyprus Gyre (Eastern Mediterranean)

Abstract. We investigated the photoproduction of ammonium (NH4+) in surface waters of the Cyprus gyre in the central Eastern Mediterranean in May 2002, in 8 on deck irradiations with freshly

Photochemical transformation of dissolved organic matter in lakes

In a survey of photochemical transformation of dissolved organic matter (DOM) in lake water, we found photochemical production of dissolved inorganic carbon (DIC) and low molecular weight carboxylic

Evaluation of indicators of nitrogen limitation in deep prairie lakes with laboratory bioassays and limnocorrals

A large proportion of blue-green algae and low inorganic nitrogen levels are not indicative per se of nitrogen limitation in lakes, but for a short period after an unusual storm, phytoplankton biomass was stimulated by nitrogen additions.

Changes in composition and reactivity of allochthonous DOM in a prairie saline lake

Inland saline lakes in semiarid regions of the Canadian prairies contain some of the highest known concentrations of dissolved organic carbon (DOC). This dissolved organic matter (DOM) represents a

Photochemical and microbial degradation of external dissolved organic matter inputs to rivers

Photochemical and microbial degradation of external inputs of dissolved organic matter (DOM) from both natural (forests) and anthropogenic (swine and equine pastures) non-point sources to rivers were

Effect of ultraviolet light on dissolved nitrogen transformations in coastal lagoon water

The effect of ultraviolet radiation on the production of inorganic nitrogen, urea, and amino acids from aquatic dissolved organic matter (DOM) was investigated for waters from Hog Island Bay, a

Photochemical production of dissolved inorganic nitrogen and primary amines from dissolved organic nitrogen in waters of two estuaries and adjacent surficial groundwaters

Recent studies have shown that in a number of humic-rich surface waters in North America, NH 4 + is released when dissolved organic matter (DOM) is exposed to sunlight. However, photochemical NH 4 +

Summer inputs of riverine nutrients to the Baltic Sea: Bioavailability and eutrophication relevance

Most nitrogen and phosphorus transported by world rivers to the oceans is associated with dissolved organic matter. However, organic matter as a potential source of N and P has hitherto been largely

Inorganic and organic nitrogen cycling in the Southern California Bight

On the basis of mass balance calculations performed for nitrogen (N) uptake experiments in the Southern California Bight (SCB), it has been suggested that a significant portion of dissolved inorganic