scholarly journals Long- and Short-Term Inorganic Nitrogen Runoff from a Karst Catchment in Austria

Forests ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1112
Author(s):  
Thomas Dirnböck ◽  
Heike Brielmann ◽  
Ika Djukic ◽  
Sarah Geiger ◽  
Andreas Hartmann ◽  
...  
Keyword(s):  
Nitrate Leaching ◽  
Biological Diversity ◽  
Inorganic Nitrogen ◽  
C Sequestration ◽  
N Deposition ◽  
Forest Stand ◽  
Karst Water ◽  
Inorganic N ◽  
The Future ◽  
Karst Catchment

Excess nitrogen (N) deposition and gaseous N emissions from industrial, domestic, and agricultural sources have led to increased nitrate leaching, the loss of biological diversity, and has affected carbon (C) sequestration in forest ecosystems. Nitrate leaching affects the purity of karst water resources, which contribute around 50% to Austria’s drinking water supply. Here we present an evaluation of the drivers of dissolved inorganic N (DIN) concentrations and fluxes from a karst catchment in the Austrian Alps (LTER Zöbelboden) from 27 years of records. In addition, a hydrological model was used together with climatic scenario data to predict expected future runoff dynamics. The study area was exposed to increasing N deposition during the 20th century (up to 30 to 35 kg N ha−1 y−1), which are still at levels of 25.5 ± 3.6 and 19.9 ± 4.2 kg N ha−1 y−1 in the spruce and the mixed deciduous forests, respectively. Albeit N deposition was close to or exceeded critical loads for several decades, 70–83% of the inorganic N retained in the catchment from 2000 to 2018, and NO3- concentrations in the runoff stayed <10 mg L−1 unless high-flow events occurred or forest stand-replacing disturbances. We identified tree growth as the main sink for inorganic N, which might together with lower runoff, increase retention of only weakly decreasing N deposition in the future. However, since recurring forest stand-replacement is predicted in the future as a result of a combination of climatically driven disturbance agents, pulses of elevated nitrate concentrations in the catchment runoff will likely add to groundwater pollution.

Drivers of long-term and short-term Nitrogen concentrations and runoff dynamics in a forested karst catchment

2020 ◽  
Author(s):  
Thomas Dirnböck ◽  
Heike Brielmann ◽  
Johannes Kobler ◽  
Andreas Hartmann
Keyword(s):  
Nitrate Leaching ◽  
Forest Ecosystems ◽  
Biological Diversity ◽  
Karst Aquifer ◽  
N Deposition ◽  
Karst Water ◽  
Runoff Water ◽  
Total N ◽  
Karst Catchment

&lt;p&gt;Excess Nitrogen (N) deposition from industrial, domestic and agricultural sources has led to increased nitrate leaching, increased gaseous N emissions, the loss of biological diversity, and has affected C sequestration in forest ecosystems. Nitrate leaching affects the purity of karst water resources, which contribute around 50 % to Austria&amp;#8217;s drinking water supply. Here we present the first comprehensive evaluation of a 26 years record of dissolved inorganic N (DIN) concentrations and fluxes from a karst catchment in the Austrian Alps (LTER Z&amp;#246;belboden), which was not affected by local N sources but solely by long-range N deposition (20-25 kg N ha&lt;sup&gt;-1&lt;/sup&gt; y&lt;sup&gt;-1&lt;/sup&gt; total N deposition). We inferred from soil chemical and microbial data as well as nitrate leaching, that the forest ecosystems in the catchment are likely saturated with respect to nitrogen. Consequently, 60-70% of the atmospheric N input was lost via leaching of NO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;-&lt;/sup&gt; to the karst aquifer or emission of N&lt;sub&gt;2&lt;/sub&gt;O to the atmosphere. However, due to high dilution DIN concentrations in the runoff rarely exceed 2 mg N l&lt;sup&gt;-1&lt;/sup&gt;. An exception were periods of forest disturbances. A number of strong storms (2007-2008) caused some major windthrows as well as single tree damages (5-10% of the catchment). Runoff concentrations of DIN showed clear responses to the disturbances with an increase (~ 1 mg N l&lt;sup&gt;-1&lt;/sup&gt;) until 2008/09 and a decreased again in 2010/11 to pre-disturbance levels. Apart from disturbances, drought years led to an increase in NO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;-&lt;/sup&gt; in the soil water in the following years. We observed the subsequent changes of the dynamics of DIN in runoff with a high-resolution water probe during 2018 and 2019. This data shows that the severity of the drought and the magnitude of the first rewetting event after a period of drought drives the size of the flush of DIN. It is likely that N deposition will lower with legislated emission reductions and that the currently N leaky ecosystems may immobilize more N when climate is becoming warmer in the future. However, we hypothesize that the karst aquifer will still receive DIN rich runoff water due to long-term lags in the recovery of a closed N cycle and because of expected climate events such as storms and droughts.&lt;/p&gt;

scholarly journals Too Much of a Good Thing? Inorganic Nitrogen (N) Inhibits Moss-Associated N2 Fixation But Organic N Can Promote It

2021 ◽  
Author(s):  
Yinliu Wang ◽  
Signe Lett ◽  
Kathrin Rousk
Keyword(s):  
Boreal Forests ◽  
Inorganic Nitrogen ◽  
N Deposition ◽  
Ecosystem Functions ◽  
Organic N ◽  
Inorganic N ◽  
Atmospheric N Deposition ◽  
Moss Species ◽  
The Impact ◽  
N Additions

Abstract Moss-associated nitrogen (N2) fixation is one of the main inputs of new N in pristine ecosystems that receive low amounts of atmospheric N deposition. Previous studies have shown that N2 fixation is inhibited by inorganic N (IN) inputs, but if N2 fixation in mosses is similarly affected by organic N (ON) remains unknown. Here, we assessed N2 fixation in two dominant mosses in boreal forests (Pleurozium schreberi and Sphagnum capillifolium) in response to different levels of N, simulating realistic (up to 4 kg N ha−1 yr−1) and extreme N deposition rates in pristine ecosystems (up to 20 kg N ha−1 yr−1) of IN (NH4NO3) and ON (alanine and urea). We also assessed if N2 fixation can recover from the N additions. In the realistic scenario, N2 fixation was inhibited by increasing NH4NO3 additions in P. schreberi but not in S. capillifolium, and alanine and urea stimulated N2 fixation in both moss species. In contrast, in the extreme N additions, increasing N inputs inhibited N2 fixation in both moss species and all N forms. Nitrogen fixation was more sensitive to N inputs in P. schreberi than in S. capillifolium and was higher in the recovery phase after the realistic compared to the extreme N additions. These results demonstrate that N2 fixation in mosses is less sensitive to organic than inorganic N inputs and highlight the importance of considering different N forms and species-specific responses when estimating the impact of N inputs on ecosystem functions such as moss-associated N2 fixation.

scholarly journals Wet deposition of atmospheric inorganic nitrogen at five remote stations on the Tibetan Plateau

2015 ◽  
Vol 15 (12) ◽  
pp. 17491-17526 ◽  
Author(s):  
Y. W. Liu ◽  
Y. S. Wang ◽  
Y. P. Pan ◽  
S. L. Piao ◽  
Keyword(s):  
Tibetan Plateau ◽  
Atmospheric Chemistry ◽  
Wet Deposition ◽  
Transport Model ◽  
Major Ions ◽  
Inorganic Nitrogen ◽  
N Deposition ◽  
The Tibetan Plateau ◽  
Inorganic N ◽  
Total N

Abstract. Alpine ecosystems on the Tibetan Plateau are sensitive to elevated nitrogen (N) deposition, and N wet deposition in this region has shown an increasing trend since the mid-20th century. However, the amount of N wet deposition on the Tibetan remains unclear, due in most part to the lack of direct observations. Using the Tibetan Observation and Research Platform network, we investigated wet deposition of the major ions (NO3−, Cl−, SO42−, NH4+, Na+, K+, Ca2+ and Mg2+) at five remote stations. At Southeast Tibet Station, Nam Co Station, Qomolangma Station, Ngari Station, and Muztagh Ata Station, the NH4+-N wet deposition was 0.63, 0.91, 1.61, 0.36 and 1.25 kg N ha−1 yr−1, respectively; the NO3−-N wet deposition was 0.28, 0.35, 0.04, 0.08 and 0.3 kg N ha−1 yr−1, respectively; and the inorganic N deposition was 0.91, 1.26, 1.64, 0.44 and 1.55 kg N ha−1 yr−1, respectively. Combining our field observations with previous studies, the average wet deposition of atmospheric NH4+-N, NO3−-N, and inorganic N on the Tibetan Plateau was estimated to be 1.17, 0.58 and 1.75 kg N ha−1 yr−1, respectively. The estimated NH4+-N : NO3−-N ratio in precipitation on the Tibetan Plateau was 2 : 1. Compared to the present study, the inorganic N wet deposition for the entire Tibetan Plateau in previous studies, either through atmospheric chemistry transport model simulations or interpolations based on limited observations, has been highly overestimated. To clarify the total N deposition on the Tibetan Plateau, it is necessary to conduct long-term and large-scale monitoring of both wet and dry deposition of N in the future.

THE DYNAMICS OF INORGANIC NITROGEN IN A FRASER VALLEY SOIL WITH AND WITHOUT SPRING OR FALL AMMONIUM NITRATE APPLICATIONS

1987 ◽  
Vol 67 (2) ◽  
pp. 367-382 ◽  
Author(s):  
C. G. KOWALENKO
Keyword(s):  
British Columbia ◽  
Ammonium Nitrate ◽  
Nitrate Leaching ◽  
Inorganic Nitrogen ◽  
Surface Acidity ◽  
Upward Movement ◽  
Pan Evaporation ◽  
Nitrogen Transformations ◽  
Inorganic N ◽  
Coastal British Columbia

Nitrogen in fallow soil in four field trials was monitored at Agassiz to examine the response of N processes under humid weather conditions of south coastal British Columbia. Inorganic N in the soil profile of control and ammonium-nitrate-treated plots were compared at various time intervals. In two trials (Spring-78 and Spring-81) treatments were applied in late May and in two (Fall-79 and Fall-82) in early November. Leaching of spring-applied N was quite limited during the spring and summer. In the Spring-78 trial, there was negligible nitrate movement until September whereas in the Spring-81 trial there was some movement in June. In the Spring-81 trial, upward movement of nitrate was detected in late August. Nitrate leaching in the summer of 1981 was associated with an unusually high amount of precipitation during June. Leaching of nitrate was significant in late October to December. Nitrogen applied in early November showed extensive leaching by late December. The ammonium appeared to have been nitrified quickly to enable leaching of the applied N as nitrate. Leaching of nitrate appeared to be associated with net water surpluses (precipitation less pan evaporation). Clay fixation of applied ammonium was detected immediately after fertilizer application in the fall but not in the spring trials. The applied ammonium that was fixed by clay was apparently released during the monitoring period. An increase of surface acidity due to ammonium nitrate application was detected in the Fall-79 trial. Comparison of nitrate leaching with long-term precipitation and pan-evaporation records shows that there is low risk of nitrate leaching during the spring and summer but high risk during the fall and winter in south coastal British Columbia. It was concluded that residual inorganic N after the growing season would not be available for crop growth in the spring due to nitrification and leaching over the winter. Development of a soil test for N would have to concentrate on the potential of the soil to mineralize soil N in the spring and early summer. Key words: Nitrogen leaching, nitrogen transformations, clay fixed NH4+, nitrification, fall nitrogen application

THE FUTURE OF CORPORATE REPORTING REFLECTIONS ON THE CRITICAL QUESTION OF THE NECESSITY OF FORWARD-THINKING PHILOSOPHY AND CULTURE OF REPORTING WORLDWIDE

2018 ◽  
Vol 28 (5) ◽  
pp. 1455-1466
Author(s):  
Hristina Oreshkova
Keyword(s):  
Financial Reporting ◽  
Biological Diversity ◽  
Radical Change ◽  
Green Economy ◽  
Critical Question ◽  
Corporate Reporting ◽  
Global Problems ◽  
The Future ◽  
Strategic Goals

Over the most recent decades corporate reporting has proved to be essential to achieving the strategic goals of humankinds and the ever-increasing necessity of truthful information and transparency. Corporate reporting is a socially significant process and practice. The quality of corporate reporting reflects the degree of relevance of the manner enterprises and businesses communicate with the surrounding world and environment (natural or industrial) and millions of people concerned – societies, present and future generations, employees, workers, and many other people, and other living beings. On most authoritative international scientific forums – symposia, conferences, congresses, assemblies, summit meetings and events, conducted in Europe and worldwide, it is pompously declared that corporate reporting should provide useful and reliable information both financial and non-financial one. The responsibilities of accountability and stewardship seem out to be of great importance to the fulfillment of the strategic goals of our centuries.The belief of the author is that the simultaneous analysis of the global problems challenging humankinds such as climate changes, destruction of biological diversity on the Planet, the matter of the necessity of actions of creating Green Ethics and Green Economy worldwide, the increasing need for combined and well-coordinated efforts in the combat supporting the eradication of poverty globally, and the relevance of corporate reporting to solving these unique problems the mankind is facing, would highlight and confirm their intricate interrelation (the key aim of the present research), consequently rendering the debate on the future of corporate reporting more meaningful and constructive. The debate would most probably promote the standpoint we personally maintain, which is also endorsed by an increasing number of supporters in Europe and around the world, implying in particular that apart from a process of unification and reduction of essential differences in the international financial reporting, what is also necessary is the radical change in the philosophy and culture of corporate reporting and presentation. Undeniably, it includes revealing of the financial state and the substantial effects and impacts of the businesses operating activities in a straightforward manner, as complete insights and understanding of the broader and far-reaching goals to which the corporate reporting must be subordinated – at present and in the long-lasting future.

scholarly journals Inorganic Nitrogen Production and Removal along the Sediment Gradient of a Stormwater Infiltration Basin

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 320
Author(s):  
Qianyao Si ◽  
Mary G. Lusk ◽  
Patrick W. Inglett
Keyword(s):  
Removal Efficiency ◽  
N Mineralization ◽  
Inorganic Nitrogen ◽  
Dry Season ◽  
Pollutant Removal ◽  
Net N Mineralization ◽  
Wet Season ◽  
Inorganic N ◽  
N Removal ◽  
Stormwater Infiltration

Stormwater infiltration basins (SIBs) are vegetated depressions that collect stormwater and allow it to infiltrate to underlying groundwater. Their pollutant removal efficiency is affected by the properties of the soils in which they are constructed. We assessed the soil nitrogen (N) cycle processes that produce and remove inorganic N in two urban SIBs, with the goal of further understanding the mechanisms that control N removal efficiency. We measured net N mineralization, nitrification, and potential denitrification in wet and dry seasons along a sedimentation gradient in two SIBs in the subtropical Tampa, Florida urban area. Net N mineralization was higher in the wet season than in the dry season; however, nitrification was higher in the dry season, providing a pool of highly mobile nitrate that would be susceptible to leaching during periodic dry season storms or with the onset of the following wet season. Denitrification decreased along the sediment gradient from the runoff inlet zone (up to 5.2 μg N/g h) to the outermost zone (up to 3.5 μg N/g h), providing significant spatial variation in inorganic N removal for the SIBs. Sediment accumulating around the inflow areas likely provided a carbon source, as well as maintained stable anaerobic conditions, which would enhance N removal.

Effects of nitrogen deposition on nitrate leaching from forests of the northeastern United States will change with tree species composition

2017 ◽  
Vol 47 (8) ◽  
pp. 997-1009 ◽  
Author(s):  
Katherine F. Crowley ◽  
Gary M. Lovett
Keyword(s):  
United States ◽  
Species Composition ◽  
Nitrate Leaching ◽  
Tree Species ◽  
N Deposition ◽  
Red Oak ◽  
Northeastern United States ◽  
Tree Species Composition ◽  
White Ash ◽  
Species Change

As tree species composition in forests of the northeastern United States changes due to invasive forest pests, climate change, or other stressors, the extent to which forests will retain or release N from atmospheric deposition remains uncertain. We used a species-specific, dynamic forest ecosystem model (Spe-CN) to investigate how nitrate (NO3–) leaching may vary among stands dominated by different species, receiving varied atmospheric N inputs, or undergoing species change due to an invasive forest pest (emerald ash borer; EAB). In model simulations, NO3– leaching varied widely among stands dominated by 12 northeastern North American tree species. Nitrate leaching increased with N deposition or forest age, generally with greater magnitude for deciduous (except red oak) than coniferous species. Species with lowest baseline leaching rates (e.g., red spruce, eastern hemlock, red oak) showed threshold responses to N deposition. EAB effects on leaching depended on the species replacing white ash: after 100 years, predicted leaching increased 73% if sugar maple replaced ash but decreased 55% if red oak replaced ash. This analysis suggests that the effects of tree species change on NO3– leaching over time may be large and variable and should be incorporated into predictions of effects of N deposition on leaching from forested landscapes.

scholarly journals Atmospheric inorganic nitrogen input via dry, wet, and sea fog deposition to the subarctic western North Pacific Ocean

2013 ◽  
Vol 13 (1) ◽  
pp. 411-428 ◽  
Author(s):  
J. Jung ◽  
H. Furutani ◽  
M. Uematsu ◽  
S. Kim ◽  
S. Yoon
Keyword(s):  
Pacific Ocean ◽  
North Pacific ◽  
Western North Pacific ◽  
Inorganic Nitrogen ◽  
North Pacific Ocean ◽  
Inorganic N ◽  
Fog Water ◽  
Western North Pacific Ocean ◽  
Sea Fog ◽  
Fog Deposition

Abstract. Aerosol, rainwater, and sea fog water samples were collected during the cruise conducted over the subarctic western North Pacific Ocean in the summer of 2008, in order to estimate dry, wet, and sea fog deposition fluxes of atmospheric inorganic nitrogen (N). During sea fog events, mean number densities of particles with diameters larger than 0.5 μm decreased by 12–78%, suggesting that particles with diameters larger than 0.5 μm could act preferentially as condensation nuclei (CN) for sea fog droplets. Mean concentrations of nitrate (NO3−), methanesulfonic acid (MSA), and non sea-salt sulfate (nss-SO42−) in sea fog water were higher than those in rainwater, whereas those of ammonium (NH4+) in both sea fog water and rainwater were similar. These results reveal that sea fog scavenged NO3− and biogenic sulfur species more efficiently than rain. Mean dry, wet, and sea fog deposition fluxes for atmospheric total inorganic N (TIN; i.e. NH4+ + NO3−) over the subarctic western North Pacific Ocean were estimated to be 4.9 μmol m−2 d−1, 33 μmol m−2 d−1, and 7.8 μmol m−2 d−1, respectively. While NO3− was the dominant inorganic N species in dry and sea fog deposition, inorganic N supplied to surface waters by wet deposition was predominantly by NH4+. The contribution of dry, wet, and sea fog deposition to total deposition flux for TIN (46 μmol m−2 d−1) were 11%, 72%, and 17%, respectively, suggesting that ignoring sea fog deposition would lead to underestimate of the total influx of atmospheric inorganic N into the subarctic western North Pacific Ocean, especially in summer periods.

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