Nitrification is a key process of thesoil nitrogen cycle, oxidizes ammonia to nitrite and then to nitrate in the soil, is a main source of N2O and NO to the atmosphere, and is responsible for reduced efficiency of ammonium-based fertilizers through leaching and denitrification of nitrate (Zerullaet al., 2001; Macadam et al., 2003).The results found in this study showed that addition of NI with urea fertilizer increased NH4 concentration and decreased its conversion to nitrate.These findings are supported by several studies that also proved that Nis suppress nitrification and thus improve nitrogen efficiency (Di and Cameron 2005, 2006; Di et al. 2007; Moir et al. 2007; Sahrawat 2004; Singh and Verma 2007). As it can be observed from the results (Table 1), all applied treatments (except Urea alone) decreased NO3 concentration at all levels. Therefore, addition of nitrification inhibitors (NIs) to fertilizers have proven to be advantageous for reducingnitrate leaching andnitrous oxide emissions,which, as a result, increase plant growth (Zaman et al., 2009).This study showed that results are site and experiment specific, and nitrification inhibitors had differing effects on different soil textures, depending largely on the concentration of inhibitors applied.
In addition, several studies indicate that potential soil nitrification effects differ among ecosystems, and that these differences do not seem to be associated directly with physical or chemical soil characteristics (Clark et al., 1960, Hattenschwiler and Vitousek, 2000; Lata et al., 2004; Laverman et al. 2000; Lovett et al. 2004; Montagnini et al. 1989; Northup et al. 1995; Robertson, 1982 a, Robertson, 1982 b and Schimel et al., 1998). In several other studies, it was shown th...
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...extural variation. However, further studies areneeded to evaluate the effects of nitrification inhibitors on ammoniavolatilization, another important N loss pathway, as few studies have reported that nitrificationinhibitors may enhance ammonia volatilization fromsoils with high pH (Kim et al., 2012). Another interesting result found about DCD treatments is that DCD is very short lived as its effect diminishes greatly by the 30th day in almost all parameters in both soils, as compared to the other inhibitors applied; these results are supported by Di et al. (2009). This conclusion is furthersupported by the lack of a significant impact on bacteria and archeae in the two soils at the 30th day of incubation. Similarly, O’Callaghan et al. (2010) also found that DCD was relatively benign and did not affect the soil microbial communities, which is supported by our results.
For years farmers have been adding natural fertilizers to their crops. It is a big risk though. Over fertilizing is very dangerous. It puts high concentrations of salt into the soil. It can also affect the water resources nearby. Nitrogen, Phosphate, and Potassium are the basics of fertilizer. If a certain nutrient is short in supply the fertilizer might not work as well. Calcium, iron, manganese are also nutrients that might be needed. So don’t just trust the fertilizer bag that says it has all the nutrients, test it out. (Miller and Levine 717)
Currently, the United State’s Gulf of Mexico experiences an annual, seasonal “dead zone” as a result of hypoxia. Hypoxia is a low level of dissolved oxygen (<2mg/L) in an area of water. Hypoxia is typically temporary and seasonal, but the low oxygen levels can be devastating to aquatic organisms. Hypoxia occurs in many oceanic waters worldwide, but there is a growing area of concern in our Gulf of Mexico coast. Hypoxia is largely caused by nitrogen fertilizer application for agriculture, with heavy concentrations coming from the Midwestern US. Nitrogen mobilizes as nitrate, and is transported via surface water runoff. The runoff enters tile-drain supported ditches, enters streams and joins the Mississippi river, eventually reaching the gulf. Nitrate mobilization is a problem for human health, and ag. runoff is also often attributed to the contamination of surface and well-water sources in rural areas. High levels of nitrates restrict the ability of red blood cells to carry oxygen. This can harm humans, and is the major cause of infant methemoglobinemia, or “blue baby syndrome”. The safe drinking level standard is 10mg/L.
As shown in Fig. 5, the final pH of the NaClO-NH3 solution after simultaneous removal are 5.4, 6.9, 7.2, 7.5, 8.5, 9.6, 10.7, 11.5 and 12.8 with respect to the initial pH of 5, 6, 7, 8, 9, 10, 11, 12 and 13, from which, an interesting law can be concluded as that if the initial pH is an acidic, the final pH is slightly increased; but if the initial pH is an alkaline, the final pH is declined. NaClO-NH3 is macromolecule compounds with a large inter surface area. It contains abundant functional groups such as hydroxyl (OH), carboxyl (COO), quinone, amino (–NH2), etc, which determines that NaClO-NH3 is a salt of strong base and weak acid, as well the ionization equilibrium and hydrolytic equilibrium would be complicated. When the pH of the NaClO-NH3 solution was acidic, the functional groups such as OH, COO and NH2- would react with H+ to generate the NH3 sediment, resulting in a decrease of inter surface area owing to the block and a great loss of NaClO-NH3, then the NOx removal as well as the duration time was decreased. As for the increase of the final pH in the acidic conditions, this was a result of the consumption of H+ by NaClO. The decrease of the
The major sites for the production of ammonia are the intestines, liver, and kidneys. It is biosynthesized through normal amino acid metabolism. The kidneys generate ammonia from glutamine by the actions of renal glutaminase and glutamate dehydrogenase. Ammonia is formed from urea by the action of bacterial urease in the lumen of the intestine, which is absorbed from the intestine by the portal vein. Amines obtained from diet and monoamines that serve as neurotransmitters or hormones can create ammonia by action of amine oxidase. In purine and pyrimidine catabolism, amino groups attached to the rings are released as ammonia.
Every chemical element or compound have specific properties that make them different than the other. However, these properties help us to understand every element or compound in which they can be used and how we can deal with them. These properties can be chemical properties which are defined as "that property must lead to a change in the substances ' chemical structure", such as heat of combustion and flammability ("Physical and Chemical…"). Also, these properties can be physical properties which are defined as the properties "that can be measured or observed without changing the chemical nature of the substance", such as mass, volume, boiling and freezing points ("Physical and Chemical…"). These two properties are related to each other. For
...nges in soil structure and soil biota of nutrient-poor grassland. Global Change Biology 9: 585-600.
Since the dawn of civilization, all living (and some non-living) things have needed energy. When humans discovered fire, the first form of harnessed energy, it made it easier to stay warm, prepare food, make weapons, etc. Since then, humankind has been inventing new ways to harness energy and use it to our advantage. Now-a-days, people in most nations depend extremely heavily on fossil fuels – to work, travel, regulate temperature of homes, produce food, clothing, and furniture, as well as other power industries. Not only are these fossil fuels dominating our society and creating economic vulnerability, but they also produce waste that causes a number of social and environmental concerns. The waste from these fuels leads to acid rain, smog, and climate change. It also releases sulfur dioxide as well as other air pollutants that are very harmful to the human respiratory system (Morris, 1999, p. ix). There are other alternative sustainable energy sources including solar, hydroelectric, wind, and biomass. However, the main source aside from fossil fuel is nuclear energy from controlled nuclear reactions (where nuclei of radioisotopes become stable or nonradioactive by undergoing changes) in a nuclear power plant. Nuclear power produces enormous amounts of energy to serve a community. Unfortunately, nuclear energy has its own set of problems – a big one being its waste. The spent fuel from nuclear plants is radioactive. This means that it emits radiation, or penetrating rays and particles emitted by a radioactive source. Ionizing radiation is known to cause cancer, and therefore makes anyone who lives near spent nuclear waste facilities vulnerable to this incurable disease. The disposal of nuclear waste is a global issue...
Ammonium nitrate is a chemical that I first encountered in the chemistry laboratory back in high school. The physical state of ammonium nitrate is typically a white solid, and it soluble in water. The solid can either have a crystalline form or bead form.
Saline soil is also vulnerable to erosion due to the death of vegetation that held the soil together. Soil that is eroded can ‘pollute’ water too.
Farmers apply nutrients such as nitrogen, phosphorus, manure, and potassium in the form of fertilizers to produce a better product for the consumers. When these sources exceed the plants needs or if these nutrients are applied before a heavy rain then the opportunity for these excess to wash into aquatic ecosystems exists.
Agriculture also leads to soil erosion, both through rainfall and wind. This soil can damage the aquatic ecosystems it ends up in, an...
Nelissen, V, Saha, BK, Ruysschaert, G & Boeckx, P 2014, 'Effect of different biochar and fertilizer types on N2O and NO emissions', Soil Biology and Biochemistry, vol. 70, no. 0, pp. 244-55.
Fertilizers are essential to modern industrial agriculture. Two of the most important plant nutrients are nitrogen and phosphorus. Nitric acid, phosphoric acid, ...
For instance, ammonium nitrate used as ammonium nitrate fertilizer”. The philosophy of agriculture
...eochemical cycles. By increasing the amount of crops that are removed from the soil and the subsequent soil erosion, phosphorus levels in the soil have dropped. The phosphorus lost from the soils travels to aquatic ecosystems which then can cause massive algal blooms. The increased use of nitrogen based fertilizers has also altered that cycle. The fertilizers add high levels of nitrates to the soil, and in natural ecosystems, nitrates will undergo denitrification and be returned as atmospheric nitrogen. This is not the case because the nitrate levels exceed the levels of denitrification that bacteria can handle. Additionally, much of the denitrifying bacteria is found in marshes and wetlands, which are currently being destroyed at incredible rates. In some areas, the excess nitrate has made it into the ground water system and contaminated the drinking water system.