INORGANIC NITROGEN DEPOSITION WITH THE ATMOSPHERIC PRECIPITATIONS TO THE SEVASTOPOL BAY IN 2015 – 2016

Abstract. A catchment-scale mass-balance model of linked carbon and nitrogen cycling in ecosystems has been developed for simulating leaching losses of inorganic nitrogen. The model (MERLIN) considers linked biotic and abiotic processes affecting the cycling and storage of nitrogen. The model is aggregated in space and time and contains compartments intended to be observable and/or interpretable at the plot or catchment scale. The structure of the model includes the inorganic soil, a plant compartment and two soil organic compartments. Fluxes in and out of the ecosystem and between compartments are regulated by atmospheric deposition, hydrological discharge, plant uptake, litter production, wood production, microbial immobilization, mineralization, nitrification, and denitrification. Nitrogen fluxes are controlled by carbon productivity, the C:N ratios of organic compartments and inorganic nitrogen in soil solution. Inputs required are: 1) temporal sequences of carbon fluxes and pools- 2) time series of hydrological discharge through the soils, 3) historical and current external sources of inorganic nitrogen; 4) current amounts of nitrogen in the plant and soil organic compartments; 5) constants specifying the nitrogen uptake and immobilization characteristics of the plant and soil organic compartments; and 6) soil characteristics such as depth, porosity, bulk density, and anion/cation exchange constants. Outputs include: 1) concentrations and fluxes of NO3 and NH4 in soil solution and runoff; 2) total nitrogen contents of the organic and inorganic compartments; 3) C:N ratios of the aggregated plant and soil organic compartments; and 4) rates of nitrogen uptake and immobilization and nitrogen mineralization. The behaviour of the model is assessed for a combination of land-use change and nitrogen deposition scenarios in a series of speculative simulations. The results of the simulations are in broad agreement with observed and hypothesized behaviour of nitrogen dynamics in growing forests receiving nitrogen deposition.

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Isotopic composition of dissolved inorganic nitrogen in high mountain lakes: variation with altitude in the Pyrenees

Biogeosciences ◽

10.5194/bg-7-1469-2010 ◽

2010 ◽

Vol 7 (5) ◽

pp. 1469-1479 ◽

Cited By ~ 14

Author(s):

M. Bartrons ◽

L. Camarero ◽

J. Catalan

Keyword(s):

Isotopic Composition ◽

Nitrogen Deposition ◽

Pore Water ◽

Soil Type ◽

Inorganic Nitrogen ◽

Mountain Lakes ◽

High Mountain ◽

Dissolved Inorganic Nitrogen ◽

High Mountain Lakes ◽

Type Flow

Abstract. Nitrogen deposition in remote areas has increased, but the effect on ecosystems is still poorly understood. For aquatic systems, knowledge of the main processes driving the observed variation is limited, as is knowledge of how changes in nitrogen supply affect lake biogeochemical and food web processes. Differences in dissolved inorganic nitrogen (DIN) between lakes cannot be understood without considering catchment characteristics. In mountains, catchment features (e.g., thermal conditions, land cover) vary considerably with elevation. The isotopic composition of nitrogen (δ15N) is increasingly used to study aquatic ecosystem dynamics. Here we explore the variability of δ15N in DIN in high mountain lakes and show that environmental conditions that change with altitude can affect the isotopic ratio. We measured ammonium and nitrate δ15N values in atmospheric deposition, epilimnetic water, deep chlorophyll maximum water (DCMW) and sediment pore water (SPW) from eight mountain lakes in the Pyrenees, both above and below the treeline. Lakes showed relatively uniform δ15N-NH4+ values in SPW (2.2±1.6‰), with no variation corresponding to catchment or lake characteristics. We suggest that organic matter diagenesis under similar sediment conditions is responsible for the low variation between the lakes. In the water column, the range of δ15N values was larger for ammonium (−9.4‰ to 7.4‰) than for nitrate (−11.4‰ to −3.4‰), as a result of higher variation both between and within lakes (epilimnetic vs. DCM water). For both compounds part of the difference correlated with altitude or catchment features (e.g., scree proportion). Based on concentration, chemical and isotopic tendencies, we suggest that patterns arise from the distinct relative contributions of two types of water flow paths to the lakes: one from snowpack melting, with little soil interaction; and another highly influenced by soil conditions. The snow-type flow path contributes low DIN concentrations depleted in 15N, whereas the soil-type flow path contributes high nitrate concentrations with higher δ15N. The proportion of these two types of source correlates with average catchment features when there is extensive snow cover during spring and early summer and probably becomes more dependent on local characteristics around the lake as summer advances. Lake depth and pore water ammonium concentrations, among other features, introduce secondary variation. In the context of nitrogen deposition studies, lakes with higher snow-type influence will probably register changes in N deposition and pollution sources better, whereas lakes with higher soil-type influence may reflect long-term effects of vegetation and soil dynamics.

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Effects of simulated atmospheric nitrogen deposition on inorganic nitrogen content and acidification in a cold-temperate coniferous forest soil

Acta Ecologica Sinica ◽

10.1016/j.chnaes.2013.01.008 ◽

2013 ◽

Vol 33 (2) ◽

pp. 114-121 ◽

Cited By ~ 13

Author(s):

Wenlong Gao ◽

Shulan Cheng ◽

Huajun Fang ◽

Yan Chen ◽

Guirui Yu ◽

...

Keyword(s):

Nitrogen Content ◽

Forest Soil ◽

Nitrogen Deposition ◽

Inorganic Nitrogen ◽

Coniferous Forest ◽

Atmospheric Nitrogen Deposition ◽

Atmospheric Nitrogen

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Importance of high resolution nitrogen deposition data for biogeochemical modeling in the western Baltic Sea and the contribution of the shipping sector

10.5194/os-2018-71 ◽

2018 ◽

Cited By ~ 3

Author(s):

Daniel Neumann ◽

René Friedland ◽

Matthias Karl ◽

Hagen Radtke ◽

Volker Matthias ◽

...

Keyword(s):

Baltic Sea ◽

Nitrogen Deposition ◽

Atmospheric Chemistry ◽

Inorganic Nitrogen ◽

Ecosystem Model ◽

Small Scale ◽

Strong Impact ◽

Nutrient Loads ◽

Data Set ◽

Biogeochemical Models

Abstract. Atmospheric deposition accounts for up to a third of the nitrogen input into the Baltic Sea and contributes to eutrophication. It is useful to use three-dimensional biogeochemical models to evaluate the contribution of atmospheric nitrogen deposition to eutrophication because bioavailable nitrogen impacts eutrophication differently depending on time and place of input – e.g. nitrogen is processed and denitrified faster in flat coastal regions. The western Baltic Sea, which is stressed by high nutrient loads, is characterized by many small islands and a wrinkled coast line. In regions with this type of coastal features, the grid resolution of atmospheric chemistry transport models (CTMs) has a strong impact on the modeled nitrogen deposition. The aim of this study was to evaluate the benefit of finer spatially resolved deposition data as input for simulations with the ecosystem model ERGOM. This study also focused on the shipping contribution to the marine nitrogen budget via deposition of shipping-emitted nitrogen oxide (NOx). Differences in the modeled dissolved inorganic nitrogen (DIN) caused by refined nitrogen deposition were identified in some coastal sections and between the Danish islands. Patches of enhanced DIN concentrations were found distant to the coast in model runs forced by the finer resolved data. These were caused by better resolved precipitation events. The differences between fine and coarse resolution deposition of the same CTM were low compared to the difference to EMEP deposition, which was a third comparison data set. The shipping sector contributed a maximum of 10 % and on average less than 5 % to DIN. In summary, particularly small scale ecosystem model studies in bights are expected to benefit from spatially higher resolved nitrogen deposition data. The shipping sector is a relevant contributor to the marine nitrogen deposition but its contribution to the marine DIN pool is rather low.

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Inorganic nitrogen deposition in China's forests: Status and characteristics

Atmospheric Environment ◽

10.1016/j.atmosenv.2014.09.005 ◽

2014 ◽

Vol 98 ◽

pp. 474-482 ◽

Cited By ~ 44

Author(s):

Enzai Du ◽

Yuan Jiang ◽

Jingyun Fang ◽

Wim de Vries

Keyword(s):

Nitrogen Deposition ◽

Inorganic Nitrogen

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Isotopic constraints on the atmospheric sources and formation of nitrogenous species in clouds influenced by biomass burning

Atmospheric Chemistry and Physics ◽

10.5194/acp-19-12221-2019 ◽

2019 ◽

Vol 19 (19) ◽

pp. 12221-12234 ◽

Cited By ~ 8

Author(s):

Yunhua Chang ◽

Yan-Lin Zhang ◽

Jiarong Li ◽

Chongguo Tian ◽

Linlin Song ◽

...

Keyword(s):

Nitrogen Deposition ◽

Biomass Burning ◽

Inorganic Nitrogen ◽

Eastern China ◽

Chemical Properties ◽

Cloud Water ◽

Cloud Formation ◽

Transformation Mechanism ◽

Study Region ◽

Nutrient Deposition

Abstract. Predicting tropospheric cloud formation and subsequent nutrient deposition relies on understanding the sources and processes affecting aerosol constituents of the atmosphere that are preserved in cloud water. However, this challenge is difficult to address quantitatively based on the sole use of bulk chemical properties. Nitrogenous aerosols, mainly ammonium (NH4+) and nitrate (NO3-), play a particularly important role in tropospheric cloud formation. While dry and wet (mainly rainfall) deposition of NH4+ and NO3- are regularly assessed, cloud water deposition is often underappreciated. Here we collected cloud water samples at the summit of Mt. Tai (1545 m above sea level) in eastern China during a long-lasting biomass burning (BB) event and simultaneously measured for the first time the isotopic compositions (mean ±1σ) of cloud water nitrogen species (δ15N-NH4+ = −6.53 ‰ ± 4.96 ‰, δ15N-NO3- = −2.35 ‰ ± 2.00 ‰, δ18O-NO3- = 57.80 ‰ ± 4.23 ‰), allowing insights into their sources and potential transformation mechanism within the clouds. Large contributions of BB to the cloud water NH4+ (32.9 % ± 4.6 %) and NO3- (28.2 % ± 2.7 %) inventories were confirmed through a Bayesian isotopic mixing model, coupled with our newly developed computational quantum chemistry module. Despite an overall reduction in total anthropogenic NOx emission due to effective emission control actions and stricter emission standards for vehicles, the observed cloud δ15N-NO3- values suggest that NOx emissions from transportation may have exceeded emissions from coal combustion. δ18O-NO3- values imply that the reaction of OH with NO2 is the dominant pathway of NO3- formation (57 % ± 11 %), yet the contribution of heterogeneous hydrolysis of dinitrogen pentoxide was almost as important (43 % ± 11 %). Although the limited sample set used here results in a relatively large uncertainty with regards to the origin of cloud-associated nitrogen deposition, the high concentrations of inorganic nitrogen imply that clouds represent an important source of nitrogen, especially for nitrogen-limited ecosystems in remote areas. Further simultaneous and long-term sampling of aerosol, rainfall, and cloud water is vital for understanding the anthropogenic influence on nitrogen deposition in the study region.

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Increasing importance of deposition of reduced nitrogen in the United States

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1525736113 ◽

2016 ◽

Vol 113 (21) ◽

pp. 5874-5879 ◽

Cited By ~ 165

Author(s):

Yi Li ◽

Bret A. Schichtel ◽

John T. Walker ◽

Donna B. Schwede ◽

Xi Chen ◽

...

Keyword(s):

United States ◽

Nitrogen Deposition ◽

Wet Deposition ◽

Inorganic Nitrogen ◽

Rapid Development ◽

The United States ◽

Natural Ecosystems ◽

Nitrogen Emissions ◽

Reduced Nitrogen ◽

Reactive Nitrogen Emissions

Rapid development of agriculture and fossil fuel combustion greatly increased US reactive nitrogen emissions to the atmosphere in the second half of the 20th century, resulting in excess nitrogen deposition to natural ecosystems. Recent efforts to lower nitrogen oxides emissions have substantially decreased nitrate wet deposition. Levels of wet ammonium deposition, by contrast, have increased in many regions. Together these changes have altered the balance between oxidized and reduced nitrogen deposition. Across most of the United States, wet deposition has transitioned from being nitrate-dominated in the 1980s to ammonium-dominated in recent years. Ammonia has historically not been routinely measured because there are no specific regulatory requirements for its measurement. Recent expansion in ammonia observations, however, along with ongoing measurements of nitric acid and fine particle ammonium and nitrate, permit new insight into the balance of oxidized and reduced nitrogen in the total (wet + dry) US nitrogen deposition budget. Observations from 37 sites reveal that reduced nitrogen contributes, on average, ∼65% of the total inorganic nitrogen deposition budget. Dry deposition of ammonia plays an especially key role in nitrogen deposition, contributing from 19% to 65% in different regions. Future progress toward reducing US nitrogen deposition will be increasingly difficult without a reduction in ammonia emissions.

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