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Articoli di riviste sul tema "Nitrogen budgets"

Autore: Grafiati

Pubblicato: 15 marzo 2023

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1

Galloway, J. N., e H. Rodhe. "Regional atmospheric budgets of S and N fluxes: how well can they be quantified?" Proceedings of the Royal Society of Edinburgh. Section B. Biological Sciences 97 (1990): 61–80. http://dx.doi.org/10.1017/s0269727000005297.

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SynopsisRegional atmospheric sulphur/nitrogen budgets have been used in several regions of the world to help build up an overview of fluxes, reservoir contents and turnover times, and as a basis for quantitative modelling. However, there are some deficiencies in the regional budget approach. The analysis is of necessity superficial, and can give a false impression of certainty. This paper reviews the regional budgets for sulphur/nitrogen which have been created in various regions of the world, analyses their common findings, addresses the issue of uncertainty, and recommends areas of future research.Most regional sulphur/nitrogen budgets have been constructed for North America, northern Europe and a few in other parts of Europe. A common finding is that anthropogenic emissions are large relative to natural emissions and that there is substantial international transport. The results of the budget analysis, while having elements of uncertainty, have proved to be valuable both in the synthesis of knowledge, and in their contribution to the increased awareness among policy makers and the public at large about the long-range transport of sulphur/nitrogen emissions.Unfortunately, there have been few regional budgets for the developing portions of the world. Given the projected increase in population – and per capita S and N emissions for these regions – we encourage a future focus on regional sulphur/nitrogen budgets for the less developed regions of the world.

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Löhmus, Krista, Valdo Kuusemets, Mari Ivask, Sille Teiter, Jürgen Augustin e Ülo Mander. "Budgets of nitrogen fluxes in riparian grey alder forests." River Systems 13, n. 3-4 (1 gennaio 2002): 321–32. http://dx.doi.org/10.1127/lr/13/2002/321.

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3

Carey, Anne E., W. Berry Lyons, Jean-Claude Bonzongo e John C. Lehrter. "Nitrogen budget in the Upper Mississippi River watershed". Environmental and Engineering Geoscience 7, n. 3 (1 agosto 2001): 251–65. http://dx.doi.org/10.2113/gseegeosci.7.3.251.

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Abstract Nitrogen budget calculations performed for highflow and low-flow years in the major sub-basins of the Upper Mississippi River watershed show differences in nitrogen applications and discharges. Nitrogen budgets show that fertilizer is the most important input of nitrogen to the basins, but also show that atmospheric input and animal manures can be significant inputs of nitrogen to the basins. The transport of nitrogen from the land to rivers varies with the prevailing hydrologic conditions. The annual nitrogen budgets are not balanced. In years of high precipitation and river discharge, more nitrogen can be removed than had been applied that year, presumably from N stored in the soil or ground water. Storage of nitrogen in soils is a major unknown in the model, but calculations suggest that it is a significant reservoir of N.

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Prasad, Rishi, e George Hochmuth. "Understanding Nitrogen Transformations and Cycling for Sweet Corn Production in Sandy Soils". EDIS 2015, n. 8 (5 novembre 2015): 4. http://dx.doi.org/10.32473/edis-ss643-2015.

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Because sandy soils have low water and nutrient-holding capacities and Florida experiences high rainfall periodically, optimizing fertilizer use efficiency for sweet corn production is challenging. The preparation of nitrogen budgets and the implementation of effective management strategies can help farmers overcome these obstacles. This 4-page fact sheet discusses major concerns which call for nitrogen management in sweet corn production, nitrogen budget preparation and interpretation, and important differences between farm-gate and soil system budgets. Written by Rishi Prasad and George Hochmuth, and published by the UF Department of Soil and Water Science, May 2015. SL430/SS643: Understanding Nitrogen Transformations and Cycling for Sweet Corn Production in Sandy Soils (ufl.edu)

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5

Galicka, Wanda, e Tadeusz Penczak. "Total nitrogen and phosphorus budgets in the lowland Sulejow Reservoir". Archiv für Hydrobiologie 117, n. 2 (20 dicembre 1989): 177–90. http://dx.doi.org/10.1127/archiv-hydrobiol/117/1989/177.

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6

Reimer, Marie, Kurt Möller e Tobias Edward Hartmann. "Meta-analysis of nutrient budgets in organic farms across Europe". Organic Agriculture 10, S1 (26 maggio 2020): 65–77. http://dx.doi.org/10.1007/s13165-020-00300-8.

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AbstractNutrient supply to organic farms is a highly discussed topic in Europe, due to the restricted availability of external fertilizer resources and the use of contentious inputs. To optimize the flow of nutrients throughout the organic farming system, it is firstly necessary to obtain valid data on the nutrient status of organic farms. Nutrient budgets are a valid tool to investigate the nutrient demand or surplus of a system. However, there is currently no comprehensive overview of nutrient budgets of European organic farms. We therefore carried out a meta-analysis on 56 individual studies that reported either farm-gate or soil surface budgets. The analysis showed an imbalance between nutrients, a general surplus of nitrogen (45 kg N ha−1 year−1 [95% confidence interval (CI) 30, 61]), magnesium (16 kg Mg ha−1 year−1 [− 9, 40]) and sulfur (45 kg S ha−1 year−1 [− 29, 118]), a balanced phosphorus budget (0 kg P ha−1 year−1 [− 2, 2]), and a deficit for potassium (− 12 kg K ha−1 year−1 [− 21, − 3]). We observed large differences between farms that could be partly explained by farm type and budgeting method. Arable and mixed farms showed lower nitrogen, phosphor, magnesium, and sulfur budgets than dairy/beef farms or even vegetable farms, while all farm types besides dairy/beef farms showed deficits for K budgets. Further, farm-gate budget studies yielded higher budgets than soil surface budgets. Variations between studied countries could also be detected, but the coverage and comparability are low due to differences in studied farm types and budgeting method.

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7

Klages, Susanne, Claudia Heidecke, Bernhard Osterburg, John Bailey, Irina Calciu, Clare Casey, Tommy Dalgaard et al. "Nitrogen Surplus—A Unified Indicator for Water Pollution in Europe?" Water 12, n. 4 (22 aprile 2020): 1197. http://dx.doi.org/10.3390/w12041197.

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Pollution of ground-and surface waters with nitrates from agricultural sources poses a risk to drinking water quality and has negative impacts on the environment. At the national scale, the gross nitrogen budget (GNB) is accepted as an indicator of pollution caused by nitrates. There is, however, little common EU-wide knowledge on the budget application and its comparability at the farm level for the detection of ground-and surface water pollution caused by nitrates and the monitoring of mitigation measures. Therefore, a survey was carried out among experts of various European countries in order to assess the practice and application of fertilization planning and nitrogen budgeting at the farm level and the differences between countries within Europe. While fertilization planning is practiced in all of the fourteen countries analyzed in this paper, according to current legislation, nitrogen budgets have to be calculated only in Switzerland, Germany and Romania. The survey revealed that methods of fertilization planning and nitrogen budgeting at the farm level are not unified throughout Europe. In most of the cases where budgets are used regularly (Germany, Romania, Switzerland), standard values for the chemical composition of feed, organic fertilizers, animal and plant products are used. The example of the Dutch Annual Nutrient Cycling Assessment (ANCA) tool (and partly of the Suisse Balance) shows that it is only by using farm-specific “real” data that budgeting can be successfully applied to optimize nutrient flows and increase N efficiencies at the farm level. However, this approach is more elaborate and requires centralized data processing under consideration of data protection concerns. This paper concludes that there is no unified indicator for nutrient management and water quality at the farm level. A comparison of regionally calculated nitrogen budgets across European countries needs to be interpreted carefully, as methods as well as data and emission factors vary across countries. For the implementation of EU nitrogen-related policies—notably, the Nitrates Directive—nutrient budgeting is currently ruled out as an entry point for legal requirements. In contrast, nutrient budgets are highlighted as an environment indicator by the OECD and EU institutions.

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8

Collos, Y. "Nitrogen budgets and dissolved organic matter cycling". Marine Ecology Progress Series 90 (1992): 201–6. http://dx.doi.org/10.3354/meps090201.

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Matsumura, Tsuyoshi, Takashi Ishimaru e Tetsuo Yanagi. "Nitrogen and Phosphorus Budgets in Tokyo Bay." Oceanography in Japan 11, n. 6 (2002): 613–30. http://dx.doi.org/10.5928/kaiyou.11.613.

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Johnson, Dale W., e John Turner. "Nitrogen budgets of forest ecosystems: A review". Forest Ecology and Management 318 (aprile 2014): 370–79. http://dx.doi.org/10.1016/j.foreco.2013.08.028.

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11

Oenema, Oene. "Nitrogen budgets and losses in livestock systems". International Congress Series 1293 (luglio 2006): 262–71. http://dx.doi.org/10.1016/j.ics.2006.02.040.

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12

Chapin, Carmen T., e John Pastor. "Nutrient limitations in the northern pitcher plant Sarracenia purpurea". Canadian Journal of Botany 73, n. 5 (1 maggio 1995): 728–34. http://dx.doi.org/10.1139/b95-079.

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The idea that carnivorous plants capture insects to supply limiting nutrients is often conjectured but rarely tested with fertilization trials or the construction of nutrient budgets. Accordingly, Sarracenia purpurea plants were analyzed for nitrogen and phosphorus after a 4-month fertilization of the pitchers with nitrogen, phosphorus, micronutrients, combinations thereof, and insect material. Neither the number of leaves produced in the same season nor average leaf mass differed significantly between treatments. Nitrogen and phosphorus concentrations were significantly higher in those leaves that received the respective treatments. Plots of concentration versus content indicated that plants were nitrogen and phosphorus limited. A nutrient budget for nitrogen was determined by soil mineralization, insect removal from the pitchers, and rainwater analysis. This budget showed that nitrogen in captured insects is one-tenth the annual plant requirement. However, soil N mineralization is sometimes more than adequate to supply demands were it to be exploited. Key words: carnivory, Sarracenia purpurea, nutrient limitation.

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13

Liu, S. M., G. H. Hong, J. Zhang, X. W. Ye e X. L. Jiang. "Nutrient budgets for large Chinese estuaries". Biogeosciences 6, n. 10 (26 ottobre 2009): 2245–63. http://dx.doi.org/10.5194/bg-6-2245-2009.

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Abstract. Chinese rivers deliver about 5–10% of global freshwater input and 15–20% of the global continental sediment to the world ocean. We report the riverine fluxes and concentrations of major nutrients (nitrogen, phosphorus, and silicon) in the rivers of the contiguous landmass of China and Korea in the northeast Asia. The rivers are generally enriched with dissolved inorganic nitrogen (DIN) and depleted in dissolved inorganic phosphate (PO43−) with very high DIN: PO43− concentration ratios. DIN, phosphorus, and silicon levels and loads in rivers are mainly affected by agriculture activities and urbanization, anthropogenic activities and adsorption on particulates, and rock types, climate and physical denudation intensity, respectively. Nutrient transports by rivers in the summer are 3–4 times higher than those in the winter with the exception of NH4+. The flux of NH4+ is rather constant throughout the year due to the anthropogenic sources such as the sewer discharge. As nutrient composition has changed in the rivers, ecosystems in estuaries and coastal sea have also changed in recent decades. Among the changes, a shift of limiting nutrients from phosphorus to nitrogen for phytoplankton production with urbanization is noticeable and in some areas silicon becomes the limiting nutrient for diatom productivity. A simple steady-state mass-balance box model was employed to assess nutrient budgets in the estuaries. The major Chinese estuaries export <15% of nitrogen, <6% of phosphorus required for phytoplankton production and ~4% of silicon required for diatom growth in the Chinese Seas (Bohai, Yellow Sea, East China Sea, South China Sea). This suggests that land-derived nutrients are largely confined to the immediate estuaries, and ecosystem in the coastal sea beyond the estuaries is mainly supported by other nutrient sources such as regeneration, open ocean and atmospheric deposition.

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14

El-Saharty, A. "Water, Nitrogen and Phosphorus Budgets of Lake Manzalah". Journal of Marine Engineering & Technology 13, n. 3 (dicembre 2014): 57–62. http://dx.doi.org/10.1080/20464177.2014.11658122.

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15

Pathak, H., S. Mohanty, N. Jain e A. Bhatia. "Nitrogen, phosphorus, and potassium budgets in Indian agriculture". Nutrient Cycling in Agroecosystems 86, n. 3 (25 giugno 2009): 287–99. http://dx.doi.org/10.1007/s10705-009-9292-5.

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Katsoulis, B. D., e D. M. Whelpdale. "Atmospheric sulfur and nitrogen budgets for southeast Europe". Atmospheric Environment. Part A. General Topics 24, n. 12 (gennaio 1990): 2959–70. http://dx.doi.org/10.1016/0960-1686(90)90476-4.

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17

Holland, Elisabeth A., Frank J. Dentener, Bobby H. Braswell e James M. Sulzman. "Contemporary and pre-industrial global reactive nitrogen budgets". Biogeochemistry 46, n. 1-3 (luglio 1999): 7–43. http://dx.doi.org/10.1007/bf01007572.

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18

Somasundar, K., A. Rajendran, M. Dileep Kumar e R. Sen Gupta. "Carbon and nitrogen budgets of the Arabian Sea". Marine Chemistry 30 (gennaio 1990): 363–77. http://dx.doi.org/10.1016/0304-4203(90)90081-m.

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19

Senft, R. L., M. A. Stillwell e L. R. Rittenhouse. "Nitrogen and Energy Budgets of Free-Roaming Cattle". Journal of Range Management 40, n. 5 (settembre 1987): 421. http://dx.doi.org/10.2307/3899602.

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20

Vlahos, Penny, Michael M. Whitney, Christina Menniti, John R. Mullaney, Jonathan Morrison e Yan Jia. "Nitrogen budgets of the Long Island Sound estuary". Estuarine, Coastal and Shelf Science 232 (gennaio 2020): 106493. http://dx.doi.org/10.1016/j.ecss.2019.106493.

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Zhao, Zhong Hua, e Zu Min Qiu. "Research on Nitrogen Budgets of Agricultural Fields of the Tao River Basin". Advanced Materials Research 281 (luglio 2011): 237–42. http://dx.doi.org/10.4028/www.scientific.net/amr.281.237.

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Based on a nitrogen (N) budget change model of agricultural fields, nitrogen budget change in each county in Tao River basin was calculated. For the whole basin, N-inputs, N-outputs and N-surpluses were obtained. The results indicated that N-inputs and N-outputs of Tao River from 2006 to 2008 increased obviously. The total N-inputs (N-outputs) in 2006, 2007 and 2008 were 31935 (18109) Tg, 33162 (17982) Tg and 33878 (19048) Tg, respectively. Compared the sources of N inputs, chemical fertilizer accounted for 44.94%, followed by human and animal excreta with 26.06%. For the N-outputs, the percent of crop harvest was biggest with 49.36%. N surpluses were 13826 Tg yr-1 in 2006, 15179 Tg yr-1 in 2007 and 15829 Tg yr-1 in 2008g. Annual growth rates were 9.9% in 2007 related to 2006 and 4.3% in 2008 related to 2007. The N-budgets with positive values showed that it increased significantly. Therefore, it was very urgent to control the non-point source of nitrogen pollution in Tao River basin.

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22

Wu, Lu, Thomas H. Misselbrook, Liping Feng e Lianhai Wu. "Assessment of Nitrogen Uptake and Biological Nitrogen Fixation Responses of Soybean to Nitrogen Fertiliser with SPACSYS". Sustainability 12, n. 15 (23 luglio 2020): 5921. http://dx.doi.org/10.3390/su12155921.

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Chemical fertiliser nitrogen addition will inhibit biological nitrogen fixation (BNF) for soybean (Glycine max [L.] Merr) growth. The optimal balance of these two nitrogen input sources has been a key issue for sustainable development in Northeast China. We used the data collected from a four-year experiment with varied irrigation and fertiliser treatments from 2007 to 2010 to evaluate the SPACSYS (Soil-Plant-Atmosphere Continuum SYStem) model. The validated model was run to investigate the responses to different management practices in seed yield, BNF, protein yield and soil nitrogen budgets. Scenario testing showed average yield increase of 2.4–5.2% with additional 50–100 kg N/ha application. Irrigation at the reproductive stage improved seed yield in drier years with an increase of 12–33% compared with the rain-fed treatment. BNF was suppressed by fertiliser nitrogen application and drought stress with a decrease of 6–33% and 8–34%, respectively. The average nitrogen budget without fertilization indicated a deficit of 39 kg N/ha. To attain higher seed yield, applying fertiliser at 25–30 and 15–20 kg N/ha before sowing is advised in drier and wetter years, respectively. To achieve a higher seed nitrogen content, an application rate of 55–60 and 45–50 kg N/ha is recommended for drier and wetter years, respectively.

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23

Zhang, Xinning, Bess B. Ward e Daniel M. Sigman. "Global Nitrogen Cycle: Critical Enzymes, Organisms, and Processes for Nitrogen Budgets and Dynamics". Chemical Reviews 120, n. 12 (12 giugno 2020): 5308–51. http://dx.doi.org/10.1021/acs.chemrev.9b00613.

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Sutton, J. N., S. C. Johannessen e R. W. Macdonald. "A nitrogen budget for the Strait of Georgia, British Columbia, with emphasis on particulate nitrogen and dissolved inorganic nitrogen". Biogeosciences 10, n. 11 (12 novembre 2013): 7179–94. http://dx.doi.org/10.5194/bg-10-7179-2013.

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Abstract. Balanced budgets for dissolved inorganic N (DIN) and particulate N (PN) were constructed for the Strait of Georgia (SoG), a semi-enclosed coastal sea off the west coast of British Columbia, Canada. The dominant control on the N budget is the advection of DIN into and out of the SoG via Haro Strait. The annual influx of DIN by advection from the Pacific Ocean is 29 990 (±19 500) Mmol yr−1. The DIN flux advected out of the SoG is 24 300 (±15 500) Mmol yr−1. Most of the DIN that enters the SoG (~ 23 400 Mmol yr−1) is converted to particulate N (PN) in situ by primary production. However, most of the PN produced by primary production is remineralized (~ 22 000 Mmol yr−1) back into DIN within the top 50 m. The PN budget for the SoG was further constrained by nitrogen isotope composition (δ15N) that indicated regional differences in the source of PN. The southern strait receives a much higher proportion of terrigenous PN, relative to marine PN, than does the northern strait. The difference is due to the influence of the Fraser River, which discharges 1950 Mmol yr−1 of PN and 1660 Mmol yr−1 of DIN into the southern strait. The overall anthropogenic contribution of PN and DIN to the SoG is minimal relative to natural sources (> 30 000 Mmol yr−1). It is unlikely that the strait will be affected by eutrophication in the near future, although anthropogenic N sources, such as wastewater outfalls, may have significant local effects.

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Koike, I., M. Yamamuro e PC Pollard. "Carbon and nitrogen budgets of two Ascidians and their symbiont, Prochloron, in a tropical seagrass meadow". Marine and Freshwater Research 44, n. 1 (1993): 173. http://dx.doi.org/10.1071/mf9930173.

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Two species of ascidian, Didemnum molle Herdman and Lissoclinum voeltzkowi Michaelsen, were collected from a Fijian seagrass meadow. The primary production of their symbiont (Prochloron), the inorganic nitrogen metabolism and the filtration rate were measured to assess the nutritional coupling between the symbiont and the host animal. The loss of organic carbon due to the respiration of D. molle (1.1 �g at. C (mg dry wt)-1 day-1) was greater than that supplied through photosynthesis of the Prochloron (0.69 �g at. C (mg dry wt)-1 day,-1). The carbon supplied through filter-feeding appeared to supplement the ascidian's carbon budget. In contrast, organic carbon from the Prochloron of L. voeltzkowi appeared to meet the colony's respiration needs. The nitrogen budgets of both ascidian colonies were estimated from their respiration rates, the nitrogen requirement of the Prochloron, and the uptake of inorganic nitrogen and particulate organic nitrogen uptake from the water column. The nitrogen incorporated from the surrounding environment could contribute to the net nitrogen gain of the colony. However, our estimate of the nitrogen needed by the Prochloron was much greater than that which could be supplied externally. The amount of nitrogen released by the ascidians was also greater than that which could be supplied externally. This suggests that nitrogen is efficiently recycled within the symbiotic Prochloron-ascidian relationship.

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N. Kiboi, Milka, Felix K. Ngetich e Daniel N. Mugendi. "Nitrogen budgets and flows in African smallholder farming systems". AIMS Agriculture and Food 4, n. 2 (2019): 429–46. http://dx.doi.org/10.3934/agrfood.2019.2.429.

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Jin, Xinpeng, Nannan Zhang, Zhanqing Zhao, Zhaohai Bai e Lin Ma. "Nitrogen budgets of contrasting crop-livestock systems in China". Environmental Pollution 288 (novembre 2021): 117633. http://dx.doi.org/10.1016/j.envpol.2021.117633.

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Rufino, M. C., P. Brandt, M. Herrero e K. Butterbach-Bahl. "Reducing uncertainty in nitrogen budgets for African livestock systems". Environmental Research Letters 9, n. 10 (1 ottobre 2014): 105008. http://dx.doi.org/10.1088/1748-9326/9/10/105008.

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Melillo, J. M., S. Butler, J. Johnson, J. Mohan, P. Steudler, H. Lux, E. Burrows et al. "Soil warming, carbon-nitrogen interactions, and forest carbon budgets". Proceedings of the National Academy of Sciences 108, n. 23 (23 maggio 2011): 9508–12. http://dx.doi.org/10.1073/pnas.1018189108.

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Johnson, D. W., R. B. Susfalk, T. G. Caldwell, J. D. Murphy, W. W. Miller e R. F. Walker. "Fire Effects on Carbon and Nitrogen Budgets in Forests". Water, Air, & Soil Pollution: Focus 4, n. 2/3 (giugno 2004): 263–75. http://dx.doi.org/10.1023/b:wafo.0000028359.17442.d1.

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Gu, Baojing, Xiaotang Ju, Jie Chang, Ying Ge e Peter M. Vitousek. "Integrated reactive nitrogen budgets and future trends in China". Proceedings of the National Academy of Sciences 112, n. 28 (29 giugno 2015): 8792–97. http://dx.doi.org/10.1073/pnas.1510211112.

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Reactive nitrogen (Nr) plays a central role in food production, and at the same time it can be an important pollutant with substantial effects on air and water quality, biological diversity, and human health. China now creates far more Nr than any other country. We developed a budget for Nr in China in 1980 and 2010, in which we evaluated the natural and anthropogenic creation of Nr, losses of Nr, and transfers among 14 subsystems within China. Our analyses demonstrated that a tripling of anthropogenic Nr creation was associated with an even more rapid increase in Nr fluxes to the atmosphere and hydrosphere, contributing to intense and increasing threats to human health, the sustainability of croplands, and the environment of China and its environs. Under a business as usual scenario, anthropogenic Nr creation in 2050 would more than double compared with 2010 levels, whereas a scenario that combined reasonable changes in diet, N use efficiency, and N recycling could reduce N losses and anthropogenic Nr creation in 2050 to 52% and 64% of 2010 levels, respectively. Achieving reductions in Nr creation (while simultaneously increasing food production and offsetting imports of animal feed) will require much more in addition to good science, but it is useful to know that there are pathways by which both food security and health/environmental protection could be enhanced simultaneously.

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Li, Xiang’an, Zhiming Yu, Xiuxian Song, Xihua Cao e Yongquan Yuan. "Nitrogen and phosphorus budgets of the Changjiang River estuary". Chinese Journal of Oceanology and Limnology 29, n. 4 (luglio 2011): 762–74. http://dx.doi.org/10.1007/s00343-011-0505-9.

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Mikkelsen, D. S. "Nitrogen budgets in flooded soils used for rice production". Plant and Soil 100, n. 1-3 (febbraio 1987): 71–97. http://dx.doi.org/10.1007/bf02370933.

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Ding, Ning, Jingfeng Zhu, Xiao Li e Xiangrong Wang. "Spatiotemporal Dynamics of Nitrogen Budgets under Anthropogenic Activities in Metropolitan Areas". Sustainability 13, n. 4 (12 febbraio 2021): 2006. http://dx.doi.org/10.3390/su13042006.

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The rapid growth of metropolitan regions is closely associated with high nitrogen (N) flows, which is known as the most important reason for widespread water pollution. It is, therefore, crucial to explore the spatiotemporal patterns of N budgets under intensive human activity. In this study, we estimated the long-term (2000–2015) N budgets by integrating the net anthropogenic nitrogen input (NANI) and the export coefficient model (ECM) in the Yangtze River Delta Urban Agglomeration (YRDUA), a typical metropolitan area with strong human disturbances. The results revealed that the NANI decreased by 10% from 2000 to 2015, while N exports showed a 6% increase. Hotspots for N budgets were found in the northeastern areas, where cropland and construction land were dominant. The linear regression showed a close relationship between the NANI and N export, and about 18% of the NANI was exported into the river system. By revealing the critical sources and drivers of N budgets over time, our work aimed to provide effective information for regional policy on nitrogen management. Future strategies, such as improving the fertilizer efficiency, optimizing the land use pattern, and controlling the population density, are necessary in order to address the environmental challenge concerns of excessive N.

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Codispoti, L. A., Jay A. Brandes, J. P. Christensen, A. H. Devol, S. W. A. Naqvi, Hans W. Paerl e T. Yoshinari. "The oceanic fixed nitrogen and nitrous oxide budgets: Moving targets as we enter the anthropocene?" Scientia Marina 65, S2 (30 dicembre 2001): 85–105. http://dx.doi.org/10.3989/scimar.2001.65s285.

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O'Brien, Katherine R., Tony R. Weber, Catherine Leigh e Michele A. Burford. "Sediment and nutrient budgets are inherently dynamic: evidence from a long-term study of two subtropical reservoirs". Hydrology and Earth System Sciences 20, n. 12 (13 dicembre 2016): 4881–94. http://dx.doi.org/10.5194/hess-20-4881-2016.

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Abstract. Accurate reservoir budgets are important for understanding regional fluxes of sediment and nutrients. Here we present a comprehensive budget of sediment (based on total suspended solids, TSS), total nitrogen (TN) and total phosphorus (TP) for two subtropical reservoirs on rivers with highly intermittent flow regimes. The budget is completed from July 1997 to June 2011 on the Somerset and Wivenhoe reservoirs in southeast Queensland, Australia, using a combination of monitoring data and catchment model predictions. A major flood in January 2011 accounted for more than half of the water entering and leaving both reservoirs in that year, and approximately 30 % of water delivered to and released from Wivenhoe over the 14-year study period. The flood accounted for an even larger proportion of total TSS and nutrient loads: in Wivenhoe more than one-third of TSS inputs and two-thirds of TSS outputs between 1997 and 2011 occurred during January 2011. During non-flood years, mean historical concentrations provided reasonable estimates of TSS and nutrient loads leaving the reservoirs. Calculating loads from historical mean TSS and TP concentrations during January 2011, however, would have substantially underestimated outputs over the entire study period, by up to a factor of 10. The results have important implications for sediment and nutrient budgets in catchments with highly episodic flow. First, quantifying inputs and outputs during major floods is essential for producing reliable long-term budgets. Second, sediment and nutrient budgets are dynamic, not static. Characterizing uncertainty and variability is therefore just as important for meaningful reservoir budgets as accurate quantification of loads.

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37

Vogt, E., C. F. Braban, U. Dragosits, M. R. Theobald, M. F. Billett, A. J. Dore, Y. S. Tang et al. "Estimation of nitrogen budgets for contrasting catchments at the landscape scale". Biogeosciences Discussions 9, n. 7 (23 luglio 2012): 8989–9028. http://dx.doi.org/10.5194/bgd-9-8989-2012.

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Abstract. A comprehensive assessment of nitrogen (N) flows at the landscape scale is fundamental to understand spatial interactions in the N cascade and to inform the development of locally optimised N management strategies. To explore this interactions, complete N budgets were estimated for two contrasting hydrological catchments (dominated by agricultural grassland vs. semi-natural peat-dominated moorland), forming part of an intensively studied landscape in southern Scotland. Local scale atmospheric dispersion modelling and detailed farm and field inventories provided high resolution estimations of input fluxes. Agricultural inputs (i.e. grazing excreta, organic and synthetic fertiliser) accounted for most of the catchment N inputs with 80% in the grassland and 57% in the moorland catchment, while atmospheric deposition made a significant contribution, particularly in the moorland catchment with 38% of the N inputs. The estimated catchment N budgets highlighted areas of key uncertainty, particularly N2 emissions from denitrification and stream N export. The resulting N balances suggest that the study catchments have a limited capacity to store N within soils, vegetation and groundwater. The "catchment N retention", i.e. the amount of N which is either stored within the catchment or lost through atmospheric emissions, was estimated to be 3% of the net anthropogenic input in the moorland and 55% in the grassland catchment. These values contrast with regional scale estimates: catchment retentions of net anthropogenic input estimated within Europe at the regional scale range from 50% to 90% with an average of 82% (Billen et al., 2011). This study emphasises the need for detailed budget analyses to identify the N status of European landscapes.

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Vogt, E., C. F. Braban, U. Dragosits, M. R. Theobald, M. F. Billett, A. J. Dore, Y. S. Tang et al. "Estimation of nitrogen budgets for contrasting catchments at the landscape scale". Biogeosciences 10, n. 1 (9 gennaio 2013): 119–33. http://dx.doi.org/10.5194/bg-10-119-2013.

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Abstract (sommario):

Abstract. A comprehensive assessment of nitrogen (N) flows at the landscape scale is fundamental to understand spatial interactions in the N cascade and to inform the development of locally optimised N management strategies. To explore these interactions, complete N budgets were estimated for two contrasting hydrological catchments (dominated by agricultural grassland vs. semi-natural peat-dominated moorland), forming part of an intensively studied landscape in southern Scotland. Local scale atmospheric dispersion modelling and detailed farm and field inventories provided high resolution estimations of input fluxes. Direct agricultural inputs (i.e. grazing excreta, N2 fixation, organic and synthetic fertiliser) accounted for most of the catchment N inputs, representing 82% in the grassland and 62% in the moorland catchment, while atmospheric deposition made a significant contribution, particularly in the moorland catchment, contributing 38% of the N inputs. The estimated catchment N budgets highlighted areas of key uncertainty, particularly N2 exchange and stream N export. The resulting N balances suggest that the study catchments have a limited capacity to store N within soils, vegetation and groundwater. The "catchment N retention", i.e. the amount of N which is either stored within the catchment or lost through atmospheric emissions, was estimated to be 13% of the net anthropogenic input in the moorland and 61% in the grassland catchment. These values contrast with regional scale estimates: Catchment retentions of net anthropogenic input estimated within Europe at the regional scale range from 50% to 90%, with an average of 82% (Billen et al., 2011). This study emphasises the need for detailed budget analyses to identify the N status of European landscapes.

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39

Skeffington, R. "European nitrogen policies, nitrate in rivers and the use of the INCA model". Hydrology and Earth System Sciences 6, n. 3 (30 giugno 2002): 315–24. http://dx.doi.org/10.5194/hess-6-315-2002.

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Abstract. This paper is concerned with nitrogen inputs to European catchments, how they are likely to change in future, and the implications for the INCA model. National N budgets show that the fifteen countries currently in the European Union (the EU-15 countries) probably have positive N balances – that is, N inputs exceed outputs. The major sources are atmospheric deposition, fertilisers and animal feed, the relative importance of which varies between countries. The magnitude of the fluxes which determine the transport and retention of N in catchments is also very variable in both space and time. The most important of these fluxes are parameterised directly or indirectly in the INCA Model, though it is doubtful whether the present version of the model is flexible enough to encompass short-term (daily) variations in inputs or longer-term (decadal) changes in soil parameters. As an aid to predicting future changes in deposition, international legislation relating to atmospheric N inputs and nitrate in rivers is reviewed briefly. Atmospheric N deposition and fertiliser use are likely to decrease over the next 10 years, but probably not sufficiently to balance national N budgets. Keywords: nitrogen deposition, nitrogen fertilisers, nitrogen budgets, nitrogen balance, nitrate leaching, INCA Model, environmental legislation, EU directives, air pollution, water pollution

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40

Nugrahadi, Mochamad Saleh, Tetsuo Yanagi, Iwan G. Tejakusuma, Seno Aji e Rahmania A. Darmawan. "SEASONAL VARIATIONS OF NUTRIENT BUDGETS IN JAKARTA BAY, INDONESIA". Marine Research in Indonesia 35, n. 1 (17 settembre 2014): 9–17. http://dx.doi.org/10.14203/mri.v35i1.7.

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This study aims to quantify the fluxes of carbon, nitrogen, phosphorus, and silicate in Jakarta Bay and use these flux data to gain an initial understanding of the biogeochemical processes occurring in the system. We investigated water, suspended matter and sediments fluxes from estuarine, coastal water and outside of the bay. Water samples were analyzed for dissolved nutrients, chlorophyll-phytoplankton abundance, and their composition. Suspended matter and sediment were analyzed for carbon and nitrogen. Nutrient concentrations were high in the rivers or estuaries and then decreased rapidly seaward. Calculation budget results showed that Jakarta Bay is a sink for DIP, DIN and DSi during dry season and rainy season. In the dry season, the system is in the slightly fixation condition ([nfix-denit] = 0.03 mmol N m-2 d-1). In contrast, denitrification exceed nitrogen fixation ([nfix-denit] = -9.74 mmol N m-2 d-1) in the rainy season. Moreover, the bay produced net carbon about 2.6-32 mmol C m-2 d-1.

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41

Kuipers, P. J., M. C. Ryan e B. J. Zebarth. "Estimating nitrate loading from an intensively managed agricultural field to a shallow unconfined aquifer". Water Quality Research Journal 49, n. 1 (27 agosto 2013): 10–22. http://dx.doi.org/10.2166/wqrjc.2013.136.

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Nitrate loading from an intensively managed commercial red raspberry field to groundwater in the Abbotsford-Sumas Aquifer, British Columbia was estimated over a 1 yr period and compared with the nitrogen surplus calculated using a simple nitrogen budget. Nitrate loading was estimated as the product of recharge (estimated from climate data as total precipitation minus potential evapotranspiration (PET)) and monthly nitrate concentration measured at the water table. Most nitrate loading occurred when nitrate, accumulated in the root zone over the growing season, was leached following heavy autumn rainfall events. Elevated groundwater nitrate concentrations at the water table during the growing season when recharge was assumed to be negligible suggested that the nitrate loading was underestimated. The estimate of annual nitrate loading to the water table was high (174 kg N ha−1) suggesting that the tools currently available to growers to manage N in raspberry production are not adequate to protect groundwater quality. The calculated nitrogen surplus from the nitrogen budget (180 kg N ha−1) was similar to the measured nitrate loading suggesting that simple nitrogen budgets may be relatively effective indices of the risk of nitrate loading to groundwater.

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42

Wintjen, Pascal, Frederik Schrader, Martijn Schaap, Burkhard Beudert, Richard Kranenburg e Christian Brümmer. "Forest–atmosphere exchange of reactive nitrogen in a remote region – Part II: Modeling annual budgets". Biogeosciences 19, n. 22 (22 novembre 2022): 5287–311. http://dx.doi.org/10.5194/bg-19-5287-2022.

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Abstract. To monitor the effect of current nitrogen emissions and mitigation strategies, total (wet + dry) atmospheric nitrogen deposition to forests is commonly estimated using chemical transport models or canopy budget models in combination with throughfall measurements. Since flux measurements of reactive nitrogen (Nr) compounds are scarce, dry deposition process descriptions as well as the calculated flux estimates and annual budgets are subject to considerable uncertainties. In this study, we compared four different approaches to quantify annual dry deposition budgets of total reactive nitrogen (ΣNr) at a mixed forest site situated in the Bavarian Forest National Park, Germany. Dry deposition budgets were quantified based on (I) 2.5 years of eddy covariance flux measurements with the Total Reactive Atmospheric Nitrogen Converter (TRANC); (II) an in situ application of the bidirectional inferential flux model DEPAC (Deposition of Acidifying Compounds), here called DEPAC-1D; (III) a simulation with the chemical transport model LOTOS-EUROS (Long-Term Ozone Simulation – European Operational Smog) v2.0, using DEPAC as dry deposition module; and (IV) a canopy budget technique (CBT). Averaged annual ΣNr dry deposition estimates determined from TRANC measurements were 4.7 ± 0.2 and 4.3 ± 0.4 kg N ha−1 a−1, depending on the gap-filling approach. DEPAC-1D-modeled dry deposition, using concentrations and meteorological drivers measured at the site, was 5.8 ± 0.1 kg N ha−1 a−1. In comparison to TRANC fluxes, DEPAC-1D estimates were systematically higher during summer and in close agreement in winter. Modeled ΣNr deposition velocities (vd) of DEPAC-1D were found to increase with lower temperatures and higher relative humidity and in the presence of wet leaf surfaces, particularly from May to September. This observation was contrary to TRANC-observed fluxes. LOTOS-EUROS-modeled annual dry deposition was 6.5 ± 0.3 kg N ha−1 a−1 for the site-specific weighting of land-use classes within the site's grid cell. LOTOS-EUROS showed substantial discrepancies to measured ΣNr deposition during spring and autumn, which was related to an overestimation of ammonia (NH3) concentrations by a factor of 2 to 3 compared to measured values as a consequence of a mismatch between gridded input NH3 emissions and the site's actual (rather low) pollution climate. According to LOTOS-EUROS predictions, ammonia contributed most to modeled input ΣNr concentrations, whereas measurements showed NOx as the prevailing compound in ΣNr concentrations. Annual deposition estimates from measurements and modeling were in the range of minimum and maximum estimates determined from CBT being at 3.8 ± 0.5 and 6.7 ± 0.3 kg N ha−1 a−1, respectively. By adding locally measured wet-only deposition, we estimated an annual total nitrogen deposition input between 11.5 and 14.8 kg N ha−1 a−1, which is within the critical load ranges proposed for deciduous and coniferous forests.

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43

Andersen, Peter C., Fred M. Rhoads, Steven M. Olson e Kristen D. Hill. "Carbon and Nitrogen Budgets in Spring and Fall Tomato Crops". HortScience 34, n. 4 (luglio 1999): 648–52. http://dx.doi.org/10.21273/hortsci.34.4.648.

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Carbon and nitrogen budgets were determined for `Colonial' (spring) and `Equinox' (fall) tomato (Lycopersicon esculentum Mill.) plants grown on raised beds with black polyethylene mulch and supplied with preplant-N at 0, 67, 134, 202, or 269 kg·ha–1. For both spring and fall experiments, we quantified the partitioning of dry matter, N, and C, and determined marketable and total yield. In the spring study, the concentration of N in leaves, stems, and in total plants increased linearly with level of N fertilization, whereas a quadratic relationship described the amount of N contained in the fruit (maximum with 202 kg·ha–1). Quadratic relationships occurred between rate of fertilization and leaf weight, stem weight, total plant weight, marketable yield, and total yield in the spring study, with maximum values at 134 or 202 kg·ha–1 rates of N fertilization. In the fall crop, fewer significant relationships occurred between dependent variables and rate of N fertilization, and coefficients of determination tended to be much lower than in the spring study. The fraction of N in leaves, stems, and roots (fall study only) was influenced by N fertilization. Effects of N fertilization on the fraction of C partitioned to any plant part was either nonsignificant or significant at P = 0.05. Total yield was related to N fertilization in a quadratic manner, but marketable yield was significantly affected only in the spring study. In both studies, increasing the rate of N fertilization reduced the C: N linearly for all tissues. In all cases, the quantity of N partitioned to vegetative tissue was at least 65% of that partitioned to the fruit, and the quantity of C in the plant was at least 74% of that in the fruit. In conclusion, although N fertilization above 202 kg·ha–1 generally increased the concentration and total amount of N in vegetative tissues, it did not increase yield. Also, the highest rate of N fertilization (269 kg·ha–1) resulted in a much lower efficiency of applied N [defined as: (N plant + N fruit)/N applied], and a much higher level of residual soil nitrate-N.

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Maun, Anwar M., e Dezhou Sun. "Nitrogen and phosphorous budgets in a lacustrine sand dune ecosystem". Écoscience 9, n. 3 (gennaio 2002): 364–74. http://dx.doi.org/10.1080/11956860.2002.11682724.

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45

Ferris, H., R. C. Venette e S. S. Lau. "Population energetics of bacterial-feeding nematodes: Carbon and nitrogen budgets". Soil Biology and Biochemistry 29, n. 8 (agosto 1997): 1183–94. http://dx.doi.org/10.1016/s0038-0717(97)00035-7.

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46

Gardner, John R., Thomas R. Fisher, Thomas E. Jordan e Karen L. Knee. "Balancing watershed nitrogen budgets: accounting for biogenic gases in streams". Biogeochemistry 127, n. 2-3 (2 gennaio 2016): 231–53. http://dx.doi.org/10.1007/s10533-015-0177-1.

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47

Salazar, F. J., D. Chadwick, B. F. Pain, D. Hatch e E. Owen. "Nitrogen budgets for three cropping systems fertilised with cattle manure". Bioresource Technology 96, n. 2 (gennaio 2005): 235–45. http://dx.doi.org/10.1016/j.biortech.2004.05.013.

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48

Oelmann, Yvonne, Yvonne Kreutziger, Vicky M. Temperton, Nina Buchmann, Christiane Roscher, Jens Schumacher, Ernst-Detlef Schulze, Wolfgang W. Weisser e Wolfgang Wilcke. "Nitrogen and Phosphorus Budgets in Experimental Grasslands of Variable Diversity". Journal of Environmental Quality 36, n. 2 (marzo 2007): 396–407. http://dx.doi.org/10.2134/jeq2006.0217.

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49

Zhen-xiong, Qi, Li De-shang, Zhang Man-ping e Dong Shuang-lin. "Comparative studies on nitrogen budgets of closed shrimp polyculture systems". Chinese Journal of Oceanology and Limnology 19, n. 3 (settembre 2001): 233–42. http://dx.doi.org/10.1007/bf02850660.

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50

DOW, CHARLES L., e DAVID R. DeWALLE. "Sulfur and nitrogen budgets for five forested appalachian plateau basins". Hydrological Processes 11, n. 7 (giugno 1997): 801–16. http://dx.doi.org/10.1002/(sici)1099-1085(199706)11:7<801::aid-hyp518>3.0.co;2-7.

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