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Nitrogen Cycle Bacteria in Agricultural Soils
Published in Vivek Kumar, Rhizomicrobiome Dynamics in Bioremediation, 2021
Guillermo Bravo, Paulina Vega-Celedón, Constanza Macaya, Ingrid-Nicole Vasconez, Michael Seeger
Nitrogen is a key element in the productivity of soils and its availability is critical for agriculture. Nitrogen fertilization has allowed to increase crop yield and productivity. However, the massive application of nitrogen compounds showed negative effects on the environment: water pollution resulting from nitrate leaching, ammonia emission, generation of greenhouse gases (N2O and NO) and ecosystems’ eutrophication near agricultural sites (Küstermann et al. 2010, Rütting et al. 2018). In addition, heavy metals pollution and the high use of pesticides, such as herbicides, fungicides and insecticides, negatively affect the nitrogen microbial communities in agricultural soils (Hernández et al. 2011, Altimira et al. 2012, Walia et al. 2014, Thiour–Mauprivez et al. 2019). Therefore, the global trend is to reduce the applications of nitrogen compounds and pesticides, and to optimize the natural nitrogen cycle (Hai et al. 2009). The aims of this report are the analyses of the effects of fertilization, heavy metals and pesticides on the microbial communities associated with the nitrogen cycle in agricultural soils, and the bioremediation strategies of agricultural soils polluted with heavy metals and pesticides.
Event-Driven Systems
Published in Robert H. Kadlec, Treatment Marshes for Runoff and Polishing, 2019
Nitrogen compounds are among the principal pollutants of concern in fresh and marine waters because of their role in eutrophication, their effect on the oxygen content of receiving waters, and their potential toxicity to aquatic invertebrate and vertebrate species. Because treatment marshes deal with low ammonia loadings, toxicity and DO problems are not a principal focus. In almost all urban stormwater cases, nitrogen loadings are low enough to place them in the category of agronomic control. However, in most agricultural systems, nitrate is the dominant species, and microbial processing is of considerable importance. Often, ammonia concentrations are very low in all types of runoff wetlands. There is an omnipresent background level of organic nitrogen, both entering and leaving event-driven wetlands, which is on the order of 0.6–1.5 mgN/L.
Toxicology of Air Pollution
Published in Lorris G. Cockerham, Barbara S. Shane, Basic Environmental Toxicology, 2019
Donald E. Gardner, Susan C. M. Gardner
The most abundant nitrogen compounds in the atmosphere include nitric oxide (NO), nitrogen dioxide (NO2), and ammonia (NH3). The first two substances are produced by combustion at high temperatures and in other industrial operations. Ammonia gas is normally present in trace amounts in the atmosphere and is not considered to be a major health hazard. However, at high concentrations it produces immediate irritation of the skin, eyes, and upper and lower respiratory tract, which can cause pulmonary edema and enhance the risk of secondary bacterial infections. High atmospheric concentrations of ammonia are usually associated with an accidental release from an industrial source such as a fertilizer manufacturer or in the production of other chemical products.
Ethylsulphate based ionic liquids for denitification of liquid fuels
Published in Petroleum Science and Technology, 2022
Parimala Muniandy, Anantharaj Ramalingam
Nitrogen compounds in liquid fuel have been a concern in three aspects: (i) environmental pollutant emissions, (ii) process efficiency, and (iii) plugging and product stability (Shin et al. 2000). In addition, nitrogen compounds possess the mutagenic and carcinogenic activity, as well as toxicity (Cheng et al. 2004). Nitrogen compounds are responsible for the formation of smog, fouling, color, gum, sour gases, acid rain, and NOx emissions. In other words, nitrogen compounds naturally occurring in liquid fuel may highly inhibit to hydrodesulphurization (HDS) process (Wiwel et al. 2000) and poison acidic and metallic refinery catalysts (Anugwom et al. 2011). Therefore, it is very important to reduce the nitrogen content in liquid fuel from >70 ppm to <0.1 ppm (Jayaraman, Yang, and Yang 2006).
Global emissions of NH3, NOx, and N2O from biomass burning and the impact of climate change
Published in Journal of the Air & Waste Management Association, 2021
Casey D. Bray, William H. Battye, Viney P. Aneja, William H. Schlesinger
Nitrogen is essential to all life forms; however, excess emissions of nitrogen compounds can have detrimental impacts on human health and the environment (Battye, Aneja, and Schlesinger 2017). For example, atmospheric deposition of major reactive nitrogen species can lead to a decrease in biological diversity, soil acidification, and eutrophication of lakes and coastal zones (Erisman et al. 2013; Galloway et al. 2004; Holtgrieve et al. 2011). These specific nitrogen gases also have a negative impact on air quality. For example, oxides of nitrogen (NOx) can increase tropospheric ozone (O3) formation, nitrous oxide (N2O) is an important greenhouse gas, and ammonia (NH3) can lead to the formation of fine particulate matter (PM2.5) (Baek and Aneja 2004; Baek, Aneja, and Tong 2004; Chen et al. 2014). There are many adverse health effects associated with exposure to elevated concentrations of ozone and fine particulate matter, such as chronic bronchitis, aggravated asthma, irregular heartbeat, other cardiovascular and respiratory problems, and even death (Lelieveld et al. 2015; Pope and Dockery 2006; Pope, Ezzati, and Dockery 2009). PM2.5 is also associated with several environmental impacts, such as reduced visibility and changes in the earth’s radiational balance (Behera and Sharma 2010; Fan et al. 2005; Heald et al. 2012; Wang et al. 2012). Increased emissions of these specific nitrogen species can impact climate change as well as human health and welfare (Davidson et al. 2011; Galloway et al. 2004; Gruber and Galloway 2008).