scholarly journals The Main Features of Phosphorus Transport in World Rivers

Water ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 16
Author(s):  
Vitaly S. Savenko ◽  
Alla V. Savenko
Keyword(s):  
River Mouth ◽  
The Arctic ◽  
Phosphorus Concentration ◽  
Water Runoff ◽  
Phosphorus Transport ◽  
Continental Runoff ◽  
High Concentrations ◽  
Phosphorus Runoff ◽  
World Rivers ◽  
River Mouths

Data on the geochemistry of phosphorus in the continental runoff of dissolved and solid substances were systematized and generalized, with a separate consideration of the processes of runoff transformation in river mouth areas. It has been established that atmospheric deposition, which many authors consider to be an important source of phosphorus in river runoff and not associated with mobilization processes in catchments, actually contains phosphorus from soil-plant recycling. This is confirmed by the fact that the input of phosphorus from the atmosphere into catchments exceeds its removal via water runoff. An analysis of the mass ratio of phosphorus in the adsorbed form and in the form of its own minerals was carried out. It was shown that the maximum mass of adsorbed phosphorus is limited by the solubility of its most stable minerals. The minimum concentrations of dissolved mineral and total phosphorus were observed in the rivers of the Arctic and subarctic belts; the maximum concentrations were confined to the most densely populated temperate zone and the zone of dry tropics and subtropics. In the waters of the primary hydrographic network, the phosphorus concentration exhibited direct relationships with the population density in the catchments and the mineralization of the river water and was closely correlated with the nitrogen content. This strongly suggests that economic activity is one of the main factors in the formation of river phosphorus runoff. The generalization of the authors’ and the literature’s data on the behavior of phosphorus at the river–sea mixing zone made it possible to draw a conclusion about the nonconservative distribution of phosphorus, in most cases associated with biological production and destruction processes. The conservative behavior of phosphorus was observed only in heavily polluted river mouths with abnormally high concentrations of this element.

scholarly journals Processes determining the marine alkalinity and calcium carbonate saturation state distributions

2014 ◽  
Vol 11 (24) ◽  
pp. 7349-7362 ◽  
Author(s):  
B. R. Carter ◽  
J. R. Toggweiler ◽  
R. M. Key ◽  
J. L. Sarmiento
Keyword(s):  
Calcium Carbonate ◽  
The Arctic ◽  
Effect Of Temperature ◽  
Minor Role ◽  
Co2 Solubility ◽  
Saturation State ◽  
Marine System ◽  
Calcite Saturation ◽  
River Mouths ◽  
Arctic Surface

Abstract. We introduce a composite tracer for the marine system, Alk*, that has a global distribution primarily determined by CaCO3 precipitation and dissolution. Alk* is also affected by riverine alkalinity from dissolved terrestrial carbonate minerals. We estimate that the Arctic receives approximately twice the riverine alkalinity per unit area as the Atlantic, and 8 times that of the other oceans. Riverine inputs broadly elevate Alk* in the Arctic surface and particularly near river mouths. Strong net carbonate precipitation results in low Alk* in subtropical gyres, especially in the Indian and Atlantic oceans. Upwelling of dissolved CaCO3-rich deep water elevates North Pacific and Southern Ocean Alk*. We use the Alk* distribution to estimate the variability of the calcite saturation state resulting from CaCO3 cycling and other processes. We show that regional differences in surface calcite saturation state are due primarily to the effect of temperature differences on CO2 solubility and, to a lesser extent, differences in freshwater content and air–sea disequilibria. The variations in net calcium carbonate cycling revealed by Alk* play a comparatively minor role in determining the calcium carbonate saturation state.

scholarly journals Spectral albedo of seasonal snow during intensive melt period at Sodankylä, beyond the Arctic Circle

2013 ◽  
Vol 13 (7) ◽  
pp. 3793-3810 ◽  
Author(s):  
O. Meinander ◽  
S. Kazadzis ◽  
A. Arola ◽  
A. Riihelä ◽  
P. Räisänen ◽  
...  
Keyword(s):  
Spectral Irradiance ◽  
The Arctic ◽  
Visible Range ◽  
Air Masses ◽  
Clear Sky ◽  
Effective Grain Size ◽  
European Arctic ◽  
Small Absorption ◽  
High Concentrations ◽  
Double Monochromator

Abstract. We have measured spectral albedo, as well as ancillary parameters, of seasonal European Arctic snow at Sodankylä, Finland (67°22' N, 26°39' E). The springtime intensive melt period was observed during the Snow Reflectance Transition Experiment (SNORTEX) in April 2009. The upwelling and downwelling spectral irradiance, measured at 290–550 nm with a double monochromator spectroradiometer, revealed albedo values of ~0.5–0.7 for the ultraviolet and visible range, both under clear sky and variable cloudiness. During the most intensive snowmelt period of four days, albedo decreased from 0.65 to 0.45 at 330 nm, and from 0.72 to 0.53 at 450 nm. In the literature, the UV and VIS albedo for clean snow are ~0.97–0.99, consistent with the extremely small absorption coefficient of ice in this spectral region. Our low albedo values were supported by two independent simultaneous broadband albedo measurements, and simulated albedo data. We explain the low albedo values to be due to (i) large snow grain sizes up to ~3 mm in diameter; (ii) meltwater surrounding the grains and increasing the effective grain size; (iii) absorption caused by impurities in the snow, with concentration of elemental carbon (black carbon) in snow of 87 ppb, and organic carbon 2894 ppb, at the time of albedo measurements. The high concentrations of carbon, detected by the thermal–optical method, were due to air masses originating from the Kola Peninsula, Russia, where mining and refining industries are located.

scholarly journals CHEMICAL AND BIOLOGICAL INDICATORS FOR EVALUATION OF ARCTIC SOIL DEGRADATION AND ITS POTENTIAL TO REMEDIATION

2021 ◽  
Vol 29 (1) ◽  
pp. 33-39
Author(s):  
Tatiana S. Smirnova ◽  
Elena A. Mazlova ◽  
Olga A. Kulikova ◽  
Ilya M. Ostrovkin ◽  
Adam M. Gonopolsky ◽  
...  
Keyword(s):  
Biological Indicators ◽  
Climatic Conditions ◽  
Chloride Ions ◽  
The Arctic ◽  
Environmental Damage ◽  
Arctic Zone ◽  
Arctic Soils ◽  
Arctic Soil ◽  
Restoration Ability ◽  
High Concentrations

In recent years, significant efforts have been made to accelerate the economic development of the Arctic zone, leading to intense environmental pollution of this region, accompanied by the significant impact of accumulated environmental damage in the region. The solution to these problems is difficult due to the remoteness of these areas and severe climatic conditions. Therefore, it is important to evaluate the potential for restoration of arctic soils. For this purpose, various indicators are used, including biological ones. In the analyzed arctic soil samples, high concentrations of petroleum hydrocarbons (up to 47,000 mg/kg) and chloride-ions (0.10–0.14 wt %) were established. Microbioassay demonstrated a presence of hydrocarbon-oxidizing microorganisms: Penicillium, Azotobacter chroococcum, Bacillus subtilis, Pseudomonas oleovorans. A low enzymatic activity and specific Arctic climate point out a low self-restoration ability of the soil, demonstrated the need for its remediation. The microbioassay with microbial strains identification and soil remediation methods suitable for the Arctic zone were recommended.

scholarly journals Impact of ocean circulation on regional polar climate simulations using the Arctic Region Climate System Model

1997 ◽  
Vol 25 ◽  
pp. 203-207 ◽  
Author(s):  
David A. Bailey ◽  
Amanda H. Lynch ◽  
Katherine S. Hedström
Keyword(s):  
Sea Ice ◽  
Mixed Layer ◽  
Climate Models ◽  
Regional Climate ◽  
The Arctic ◽  
Water Runoff ◽  
Polar Regions ◽  
Ice Dynamics ◽  
Climate System Model ◽  
Ice Model

Global climate models have pointed to the polar regions as very sensitive areas in response to climate change. However, these models often do not contain representations of processes peculiar to the polar regions such as dynamic sea ice, permafrost, and Arctic stratus clouds. Further, global models do not have the resolution necessary to model accurately many of the important processes and feedbacks. Thus, there is a need for regional climate models of higher resolution. Our such model (ARCSy M) has been developed by A. Lynch and W. Chapman. This model incorporates the NCAR Regional Climate Model (RegCM2) with the addition of Flato–Hibler cavitating fluid sea-ice dynamics and Parkinson–Washington ice thermodynamic formulation. Recently work has been conducted to couple a mixed-layer ocean to the atmosphere–ice model, and a three-dimensional (3-D) dynamical ocean model, in this case the S-Coordinate Primitive Equation Model (SPEM), to the ice model. Simulations including oceanic circulation will allow investigations of the feedbacks involved in fresh-water runoff from sea-ice melt and sea-ice transport. Further, it is shown that the definition of the mixed-layer depth has significant impact on ice thermodynamics.

Quantitative comparison of forests and other areas with dry weather input loading in the Lake Biwa catchment area

2002 ◽  
Vol 45 (9) ◽  
pp. 183-193 ◽  
Author(s):  
S. Fujii ◽  
H. Tanaka ◽  
I. Somiya
Keyword(s):  
Water Quality ◽  
Lake Biwa ◽  
River Mouth ◽  
Weather Conditions ◽  
Ionic Species ◽  
Concentration Difference ◽  
Forest Sites ◽  
Catchment Areas ◽  
Unit Loading ◽  
River Mouths

For the evaluation of pollutants loading to Lake Biwa, comprehensive river surveys on river mouths and forest sites were conducted 9 times from 1996 to 1999, on 25–40 main rivers in the Lake Biwa watershed. The main results obtained are as follows. (1) River water quality reflects regional characteristics of their catchment areas, and the concentration difference among rivers ranged between 2–3 fold. (2) Concentration variation shows different patterns with time and location depending on water quality indices used. (3) Indices related to organic matter and nutrients have lower correlation between forests and river mouths, but those related to ionic species showed strong correlation. (4) Flux comparison of forest and river mouth sites suggests that pollutants from catchment areas are conveyed to the lake not only through rivers but also underground. (5) In dry weather conditions, forests contribute 30% to the whole pollutants (TN, TP, and TCODMn) loading, and the remainder is derived mainly from paddy fields and residential/commercial zones. (6) Unit loading factors from forests are estimated as 640, 57 and 1200 kg/km2/y, respectively for TN, TP and TCODMn, while those from other areas are estimated as 2,500, 208 and 4,200 kg/km2/y.

scholarly journals Nutrient enrichment effect on macroinvertebrates in a lowland stream of Argentina

2015 ◽  
Vol 105 (2) ◽  
pp. 228-234 ◽  
Author(s):  
Agustina Cortelezzi ◽  
Carolina Ocón ◽  
María V. López van Oosterom ◽  
Rosana Cepeda ◽  
Alberto Rodrigues Capítulo
Keyword(s):  
Climate Change ◽  
Global Climate Change ◽  
Global Climate ◽  
Nitrogen Concentration ◽  
Nutrient Concentrations ◽  
Phosphorus Concentration ◽  
Lowland Stream ◽  
Pampean Streams ◽  
High Concentrations ◽  
Intensive Land Use

ABSTRACT One of the most important effects derived from the intensive land use is the increase of nutrient concentration in the aquatic systems due to superficial drainage. Besides, the increment of precipitations in South America connected to the global climate change could intensify these anthropic impacts due to the changes in the runoff pattern and a greater discharge of water in the streams and rivers. The pampean streams are singular environments with high natural nutrient concentrations which could be increased even more if the predictions of global climate change for the area are met. In this context, the effect of experimental nutrient addition on macroinvertebrates in a lowland stream is studied. Samplings were carried out from March 2007 to February 2009 in two reaches (fertilized and unfertilized), upstream and downstream from the input of nutrients. The addition of nutrients caused an increase in the phosphorus concentration in the fertilized reach which was not observed for nitrogen concentration. From all macroinvertebrates studied only two taxa had significant differences in their abundance after fertilization: Corbicula fluminea and Ostracoda. Our results reveal that the disturbance caused by the increase of nutrients on the benthic community depends on basal nutrients concentration. The weak response of macroinvertebrates to fertilization in the pampean streams could be due to their tolerance to high concentrations of nutrients in relation to their evolutionary history in streams naturally enriched with nutrients. Further research concerning the thresholds of nutrients affecting macroinvertebrates and about the adaptive advantages of taxa in naturally eutrophic environments is still needed. This information will allow for a better understanding of the processes of nutrient cycling and for the construction of restoration measures in natural eutrophic ecosystems.

scholarly journals Record high peaks in PCB concentrations in the Arctic atmosphere due to long-range transport of biomass burning emissions

2007 ◽  
Vol 7 (17) ◽  
pp. 4527-4536 ◽  
Author(s):  
S. Eckhardt ◽  
K. Breivik ◽  
S. Manø ◽  
A. Stohl
Keyword(s):  
Biomass Burning ◽  
Dry Matter ◽  
The Arctic ◽  
Pcb Congeners ◽  
Range Transport ◽  
Standard Deviations ◽  
High Concentrations ◽  
Arctic Atmosphere ◽  
Primary Emissions

Abstract. Soils and forests in the boreal region of the Northern Hemisphere are recognised as having a large capacity for storing air-borne Persistent Organic Pollutants (POPs), such as the polychlorinated biphenyls (PCBs). Following reductions of primary emissions of various legacy POPs, there is an increasing interest and debate about the relative importance of secondary re-emissions on the atmospheric levels of POPs. In spring of 2006, biomass burning emissions from agricultural fires in Eastern Europe were transported to the Zeppelin station on Svalbard, where record-high levels of many air pollutants were recorded (Stohl et al., 2007). Here we report on the extremely high concentrations of PCBs that were also measured during this period. 21 out of 32 PCB congeners were enhanced by more than two standard deviations above the long-term mean concentrations. In July 2004, about 5.8 million hectare of boreal forest burned in North America, emitting a pollution plume which reached the Zeppelin station after a travel time of 3–4 weeks (Stohl et al., 2006). Again, 12 PCB congeners were elevated above the long-term mean by more than two standard deviations, with the less chlorinated congeners being most strongly affected. We propose that these abnormally high concentrations were caused by biomass burning emissions. Based on enhancement ratios with carbon monoxide and known emissions factors for this species, we estimate that 130 and 66 μg PCBs were released per kilogram dry matter burned, respectively. To our knowledge, this is the first study relating atmospheric PCB enhancements with biomass burning. The strong effects on observed concentrations far away from the sources, suggest that biomass burning is an important source of PCBs for the atmosphere.

scholarly journals Impact of ocean circulation on regional polar climate simulations using the Arctic Region Climate System Model

1997 ◽  
Vol 25 ◽  
pp. 203-207 ◽  
Author(s):  
David A. Bailey ◽  
Amanda H. Lynch ◽  
Katherine S. Hedström
Keyword(s):  
Sea Ice ◽  
Mixed Layer ◽  
Climate Models ◽  
Regional Climate ◽  
The Arctic ◽  
Water Runoff ◽  
Polar Regions ◽  
Ice Dynamics ◽  
Climate System Model ◽  
Ice Model

Global climate models have pointed to the polar regions as very sensitive areas in response to climate change. However, these models often do not contain representations of processes peculiar to the polar regions such as dynamic sea ice, permafrost, and Arctic stratus clouds. Further, global models do not have the resolution necessary to model accurately many of the important processes and feedbacks. Thus, there is a need for regional climate models of higher resolution. Our such model (ARCSy M) has been developed by A. Lynch and W. Chapman. This model incorporates the NCAR Regional Climate Model (RegCM2) with the addition of Flato–Hibler cavitating fluid sea-ice dynamics and Parkinson–Washington ice thermodynamic formulation. Recently work has been conducted to couple a mixed-layer ocean to the atmosphere–ice model, and a three-dimensional (3-D) dynamical ocean model, in this case the S-Coordinate Primitive Equation Model (SPEM), to the ice model. Simulations including oceanic circulation will allow investigations of the feedbacks involved in fresh-water runoff from sea-ice melt and sea-ice transport. Further, it is shown that the definition of the mixed-layer depth has significant impact on ice thermodynamics.

Coastal movements of migrating sea lamprey (Petromyzon marinus) in response to a partial pheromone added to river water: implications for management of invasive populations

2014 ◽  
Vol 71 (4) ◽  
pp. 533-544 ◽  
Author(s):  
Trevor D. Meckley ◽  
C. Michael Wagner ◽  
Eliezer Gurarie
Keyword(s):  
River Water ◽  
Petromyzon Marinus ◽  
River Mouth ◽  
Manual Tracking ◽  
Extensive Search ◽  
Sea Lampreys ◽  
Pheromone Components ◽  
Search Tactic ◽  
River Mouths ◽  
Intensive Search

How sea lampreys (Petromyzon marinus) search for and select reproductive habitat is poorly understood. Manual tracking of acoustically tagged migrants confirms the hypothesis that sea lampreys transition from extensive search to intensive search upon encounter with river water and return to extensive search upon leaving the plume. In addition, we document a previously unknown search tactic used to localize river mouths termed coastal rebounding. Increased intensive search in the river plume and subsequent approach to the river mouth is hypothesized to occur as a consequence of detection of a pheromone released by river resident larvae that indicate the presence of high-quality reproductive habitat. Application of two synthesized pheromone components caused migrants to increase time spent searching a plume by 57%; applications did not increase the likelihood of river entry. These findings suggest that partial pheromones constitute information that facilitates the search for river entrances, but prove insufficient to affect the decision to select a habitat. Proposed management tactics that rely on luring migrants into rivers with larval odor may prove ineffective without a complete blend of pheromone components.

Accumulation of metals in zooplankton from karst plateau reservoirs with different eutrophic status in Guizhou Province, P. R. China

Crustaceana ◽  
2016 ◽  
Vol 89 (5) ◽  
pp. 537-557 ◽  
Author(s):  
Sheng Xing Long ◽  
Yang Yang ◽  
Ping Hua Xia ◽  
Chuan Chen ◽  
Zhi Wei Liu ◽  
...  
Keyword(s):  
Bioaccumulation Factor ◽  
Guizhou Province ◽  
Phosphorus Concentration ◽  
Trophic Chain ◽  
Total Phosphorus Concentration ◽  
Characteristic Distribution ◽  
Accumulation Of Metals ◽  
Hongfeng Lake ◽  
High Concentrations ◽  
High Level

Metal concentrations in large zooplankton from three karst reservoirs with different eutrophic status (Hongfeng Lake reservoir, Baihua Lake reservoir, and Aha reservoir) in Guizhou Province, China, were investigated. Samples of zooplankton were collected in 2014 and 2015. It was found that accumulation of metals in zooplankton was significantly correlated with Chl-a (chlorophyll a), which can be attributed to the characteristic distribution of species of phytoplankton. A low concentration of metals in water means a higher bioaccumulation factor (BAF) and a stronger transfer to zooplankton via the trophic chain, and hence a higher ecological risk. Zooplankton in the eutrophic Aha reservoir had lower concentrations of Fe (mean 1264.25 mg/kg) than in Hongfeng (mean 2566.07 mg/kg) and Baihua (2246.87 mg/kg) in 2014-2015, because of high TP (Total Phosphorus) concentration, which has an affinity with suspended particles matter. A high level of Cd (mean 0.62 mg/kg) was found in Hongfeng. This study shows that zooplankton in the eutrophic Aha reservoir had higher concentrations of metals (Mn, mean 590.47 mg/kg; Pb, mean 7.6 mg/kg; Cr, mean 26.31 mg/kg; Ni, mean 8.54 mg/kg; Zn, mean 225.73 mg/kg; and Cu, mean 238.33 mg/kg) than in the mesotrophic Hongfeng and Baihua reservoirs. Thus, the eutrophic status was significantly, positively correlated with high concentrations of metals in the zooplankton, as also observed in other reservoir studies.

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