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Effect Of Manure Application Technique On Nitrous Oxide Emission From Agricultural Soils
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Book Synopsis Effect of Manure Application Technique on Nitrous Oxide Emission from Agricultural Soils by : Gerardus Lambertus Velthof
Download or read book Effect of Manure Application Technique on Nitrous Oxide Emission from Agricultural Soils written by Gerardus Lambertus Velthof and published by . This book was released on 2010 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Soil Emission of Nitrous Oxide and its Mitigation by : David Ussiri
Download or read book Soil Emission of Nitrous Oxide and its Mitigation written by David Ussiri and published by Springer Science & Business Media. This book was released on 2012-11-13 with total page 391 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitrous oxide gas is a long-lived relatively active greenhouse gas (GHG) with an atmospheric lifetime of approximately 120 years, and heat trapping effects about 310 times more powerful than carbon dioxide per molecule basis. It contributes about 6% of observed global warming. Nitrous oxide is not only a potent GHG, but it also plays a significant role in the depletion of stratospheric ozone. This book describes the anthropogenic sources of N2O with major emphasis on agricultural activities. It summarizes an overview of global cycling of N and the role of nitrous oxide on global warming and ozone depletion, and then focus on major source, soil borne nitrous oxide emissions. The spatial-temporal variation of soil nitrous oxide fluxes and underlying biogeochemical processes are described, as well as approaches to quantify fluxes of N2O from soils. Mitigation strategies to reduce the emissions, especially from agricultural soils, and fertilizer nitrogen sources are described in detail in the latter part of the book.
Book Synopsis Mitigating Gaseous Nitrogen and Carbon Losses From Northeastern Agricultural Soils Via Alternative Soil Management Practices by : Kyle Michael Dittmer
Download or read book Mitigating Gaseous Nitrogen and Carbon Losses From Northeastern Agricultural Soils Via Alternative Soil Management Practices written by Kyle Michael Dittmer and published by . This book was released on 2019 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: Traditional agricultural practices often result in gaseous losses of nitrous oxide (N2O), ammonia (NH3), and carbon dioxide (CO2), representing a net loss of nutrients from agricultural soils, which negatively impacts crop yield and requires farmers to increase nutrient inputs. By adopting best management practices (BMPs; i.e., no-tillage, cover crops, sub-surface manure application, and proper manure application timing), there is great potential to reduce these losses. Because N2O and CO2 are also greenhouse gases (GHGs), climate change mitigation via BMP adoption and emissions reductions would be an important co-benefit. However, adopting a no-tillage and cover cropping system has had setbacks within the Northeast, primarily due to concerns regarding manure nitrogen (N) losses in no-tillage systems as well as uncertainty surrounding the benefits of cover crops. This thesis used two field-trials located in Alburgh, Vermont to assess differences in (i) GHG emissions from agricultural soils, (ii) nitrate and ammonium retention, (iii) corn yield and protein content, and (iv) N uptake and retention via cover crop scavenging under a combination of different BMPs. Chapter 1 evaluates the effects of different reduced-tillage practices and manure application methods (i.e., vertical-tillage, no-tillage, manure injection, and broadcast manure application) on reducing N2O and CO2 emissions, retaining inorganic N, and improving crop yields. Greenhouse gas measurements were collected every other week for the growing season of 2015-2017 via static chamber method using a photoacoustic gas analyzer. Results from this study showed that tillage regimes and manure application method did not interact to affect any of the three research objectives, although differences between individual BMPs were observed. Notably, vertical tillage enhanced CO2 emissions relative to no-tillage, demonstrating the role of soil disturbance and aeration on aerobic microbial C transformations. Manure injection was found to significantly enhance both N2O and CO2 emission relative to broadcast application, likely due to the formation of anerobic micro-zones created from liquid manure injection. However, plots that received manure injection retained greater concentrations of soil nitrate, a vital nutrient for quality crop production, thereby highlighting a major tradeoff between gaseous N losses and N retention with manure injection. Chapter 2 evaluates the effects of tillage practices and timing of manure application to increase N retention with the use of cover crops in order to mitigate GHG emissions, enhance soil nitrate and ammonium retention, and improve cropping system N uptake. Treatments at this field trial consisted of a combination of the presence or absence of cover crops, no-tillage or conventional-tillage, and spring or fall manure application. Greenhouse gas emissions were measured every other week via static chamber method using a gas chromatograph for the growing season of 2018. Results from this study showed that the presence of cover crops enhanced both N2O and CO2 emissions relative to fallow land, irrespective of tillage regime and manure application season, likely as a result of greater N and carbon substrates entering the soil upon cover crop decomposition. Due to enhanced N2O emissions with cover crops, cover crops did not retain significantly greater inorganic N in the system upon termination.
Book Synopsis Nitrous Oxide Emissions from Agricultural Soil Receiving Manure in a Changing Climate by : Chih-Yu Hung
Download or read book Nitrous Oxide Emissions from Agricultural Soil Receiving Manure in a Changing Climate written by Chih-Yu Hung and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Soil nitrous oxide (N2O) emission varies in magnitude and occurs sporadically during the spring freeze-thaw period in cold humid temperate regions. Fluctuations in soil N2O emissions are related to soil biophysical properties, which are influenced by agricultural practices like fall application of manure and fall-sown cover crops, as well as rainfall and other weather events. The objectives of this thesis were to (1) quantify N2O emissions in the spring period from agricultural soils that received manure and were planted with a cover crop in the previous fall, (2) estimate the influence of fall-applied manure and cover crops on the spring soil N2O emissions in changing climate, (3) determine the biophysical factors that control soil N¬2O emissions after a rain-induced thawing event, and (4) propose a monitoring method to estimate N2O emissions in agricultural soils. First, I quantified the soil N2O emissions with a two-year field experiment. Soil N2O emission in the spring freeze-thaw period (c.a. 30 d) was -2.35 to 13.57 g N ha-1 and not affected by dairy manure application (solid or liquid) or cover crops (ryegrass and ryegrass/hairy vetch), possibly due to the low manure N application rate and N loss over winter. Second, I evaluated soil N2O emissions in the spring freeze-thaw period under three climate scenarios (baseline, from 1981–2010; Representative Concentration Pathway 4.5 and 8.5 from 2071–2100) with the Decomposition-Denitrification model. The model predicted that more reactive N will be retained by cover crops under future climate scenarios, but the soil N2O emissions will not increase. However, applying solid manure without a cover crop led to more soil N2O emissions than other treatments tested under three climate scenarios (9.90 to 61.50 g N ha-1, P
Book Synopsis Effect of mineral N fertilizers – N form, amount and way of application – on nitrous oxide emissions from croplands by : Ulrike Lebender
Download or read book Effect of mineral N fertilizers – N form, amount and way of application – on nitrous oxide emissions from croplands written by Ulrike Lebender and published by Cuvillier Verlag. This book was released on 2014-07-24 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present work evaluated the effect of mineral nitrogen (N) fertilizer application during crop production on the potential risk of gaseous N loss in the form of nitrous oxide (N2O). Nitrous oxide (N2O) is an environmentally important atmospheric trace gas and contributes to the anthropogenic greenhouse effect. In addition, it is a precursor to photochemical nitric oxide (NO) production in the stratosphere which leads to stratospheric ozone depletion. Agriculture is considered to be the main source of anthropogenic N2O, with agricultural soils representing the single largest source due to nitrogen fertilizer applications during crop production. The purpose of this study was to examine the effects of mineral N fertilizers (N form, amount, mode of application) on N2O emissions from fertilized croplands in north-west Germany. Therefore several field trials, one greenhouse pot experiment and two incubation experiments were conducted. Nitrous oxide fluxes were measured by means of the closed chamber method. The length of the experimental period varied between experiments from several weeks (42 days) up to one-year measurement campaigns. The amount of N2O emitted during the crop growth period depended on the N form applied as well as on the mode of application, and a linear relationship between cumulative N2O emissions and total N fertilizer amount applied was found.
Book Synopsis RAMIRAN 2017: Sustainable Utilisation of Manures and Residue Resources in Agriculture by : Tom Misselbrook
Download or read book RAMIRAN 2017: Sustainable Utilisation of Manures and Residue Resources in Agriculture written by Tom Misselbrook and published by Frontiers Media SA. This book was released on 2019-12-30 with total page 249 pages. Available in PDF, EPUB and Kindle. Book excerpt: This eBook presents highlight papers from the 17th International conference of the Recycling of Agricultural, Municipal and Industrial Residues to Agriculture Network (RAMIRAN) that was held in Wexford, Ireland in September 2017. The book contains a broad range of papers around this multidisciplinary theme covering topics including regional and national organic resource use planning, impact of livestock diet on manure composition, fate and utilisation of excreta from grazing livestock, anaerobic digestion, overcoming barriers to resource reuse, hygienic aspects of residue recycling and impacts on soil health. The overarching theme being addressed is the sustainable recycling of organic residues to agriculture, to promote effective nutrient use and minimise environmental impact.
Book Synopsis Ammonia and Nitrous Oxide Emissions Following Field-application of Manure by : Jan Huijsmans
Download or read book Ammonia and Nitrous Oxide Emissions Following Field-application of Manure written by Jan Huijsmans and published by . This book was released on 2009 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Manure application to grassland and arable land is an important source of ammonia and nitrous oxide losses. For both gasses, national and international policies have been developed with the objective of reducing the emissions. Since the early 1990s, measurements have been carried out in The Netherlands to assess the gaseous losses from manure application, especially for ammonia. Measurements of nitrous oxide emissions are relatively scarce. This paper presents the results of these measurements with the objective of providing an updated quantification of the effect of techniques for application and incorporation of manure, and to assess influencing factors. The manure application techniques differ in their spreading or placement of the manure onto the grass or soil surface or into the soil. The following techniques are treated in this paper: surface spreading, narrow-band application, shallow injection with open slots on grassland, and surface spreading, surface incorporation, deep placement on arable land. Low emission techniques such as narrow band application, shallow injection, incorporation or injection on arable land show a significant reduction of ammonia emission compared to surface spreading. On grassland, average emission factors (% of total ammonium nitrogen) were 74% for surface spreading and 16% for shallow injection. On arable land, the emission factors were 69% for surface spreading and 2% for deep placement. However, the nitrous oxide emission factor from manure applied with low ammonia emissions techniques is higher than the emission factor for surface applied manures. In a whole farm context, the higher nitrous oxide emission with shallow injection is partly offset directly by reduced emissions from fertilizer savings and indirectly from lower ammonia losses.
Book Synopsis Measured and Daycent- Simulated Nitrous Oxide Emissions from Soil Planted to Corn in Dairy Cropping Systems by : Maria Ponce De Leon Jara
Download or read book Measured and Daycent- Simulated Nitrous Oxide Emissions from Soil Planted to Corn in Dairy Cropping Systems written by Maria Ponce De Leon Jara and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Crop rotations, organic nutrient amendments, reduced tillage practices, and integration of cover crops are practices that have the potential to increase the sustainability of crop production, yet they also impact nitrous oxide (N2O) emissions. Agricultural soil management has been estimated to contribute 79% of the total N2O emissions in the U.S., and inorganic nitrogen (N) fertilization is one of the main contributors. Nitrous oxide is a potent greenhouse gas that has a global warming potential which is approximately 298 times that of carbon dioxide (CO2) over a 100-year period and is currently the dominant ozone-depleting substance. Few studies have assessed the effects of organic N amendments on direct N2O within the context of a typical dairy forage cropping system. Most research has been limited to studying the effects of one or two sources of N inputs on N2O emissions; however, dairy forage cropping systems often apply manure and have more than two N sources that likely both contribute to N2O emissions. This study investigated how different dairy cropping practices that include differences in crop residues, N inputs (dairy manure and inorganic fertilizer), timing of N amendment applications and environmental conditions influenced N2O emissions from no-till soil planted to corn (Zea mays L.). A two-year field study was carried out as part of the Pennsylvania State Sustainable Dairy Cropping Systems Experiment, where corn was planted following annual grain crops, perennial forages, and a green manure legume crop; all were amended with dairy manure. In the corn-soybean (Glycine max (L.) Merr.) rotation, N sources (dairy manure and inorganic fertilizer) and two methods of manure application (broadcasted and injected) were also compared.Chapter 1 reviews the scientific literature; describing the biotic and abiotic processes of N2O production in soils, summarizing current research on N2O emissions in agricultural systems, and emphasizing the main management and environmental drivers contributing to the emissions. This chapter reviews methods for matching N supply with crop demand, coupling N flow cycles, using advanced fertilizer techniques, and optimizing tillage management. Also, the applicability and limitations of current research to effectively reduce N2O emissions in a variety of regions are discussed.Chapter 2 analyzes the effect of corn production management practices and environmental conditions contributing to N2O in the Pennsylvania State Sustainable Dairy Cropping Systems Experiment. Significantly higher N2O emissions were observed 15-42 days after manure injection and 1-4 days after mid-season UAN application. Manure injection had 2-3 times greater potential for N2O emissions compared to broadcast manure during this time period. Integration of legumes and grasses in the cropping system reduced inorganic fertilizer use compared to soybean with manure or UAN, however, direct N2O emissions were not reduced. The Random Forest method was used to identify and rank the predictor variables for N2O emissions. The most important variables driving N2O emissions were: time after manure application, time after previous crop termination, soil nitrate, and moisture. These field research results support earlier recommendations for reducing N losses including timing N inputs close to crop uptake, and avoiding N applications when there is a high chance of precipitation to reduce nitrate accumulation in the soil and potential N losses from denitrification.Chapter 3 reports the comparison of N2O fluxes predicted with the biogeochemical model DAYCENT compared to measured data from the two-year dairy cropping systems study. Daily N2O emissions simulated by DAYCENT had between 41% and 76% agreement with measured daily N2O emissions in 2015 and 2016. DAYCENT overestimated the residual inorganic N fertilizer impact on N2O emissions in the corn following soybean with inorganic fertilizer and broadcast manure. Comparisons between DAYCENT simulated and measured N2O fluxes indicate that DAYCENT did not represent well organic N amendments from crop residues of perennials and legume cover crops, or manure application in no-till dairy systems. DAYCENT was generally able to reproduce temporal patterns of soil temperature, but volumetric soil water contents (VSWC) predicted by DAYCENT were generally lower than measured values. After precipitation events, DAYCENT predicted that VSWC tended to rapidly decrease and drain to deeper layers. Both the simulated and measured soil inorganic N increased with N fertilizer addition; however, the model tended to underestimate soil inorganic N concentration in the 0-5 cm layer. Our results suggest that DAYCENT overestimated the residual N impact of inorganic fertilizer on N2O emissions and mineralization of organic residues and nitrification happened faster than DAYCENT predicted. Chapter 4 highlights the impact of manure injection and the importance of timing organic N amendments from manures and/or crop residue with crop N uptake to mitigate N2O emissions. More research is needed to better understand the tradeoffs of these strategies in no till dairy cropping systems to help farmers in their operational management decisions. Improving the parametrization of DAYCENT for dairy cropping systems in no-till systems with high surface legume crop residues from perennials and cover crops, will make the model a more useful tool for testing different mitigation scenarios for farmers and policy-designer decision making.
Book Synopsis Direct and Indirect Nitrous Oxide Emissions from Agricultural Soils, 1990-2003. Background Document on the Calculation Method for the Dutch National Inventory Repor by :
Download or read book Direct and Indirect Nitrous Oxide Emissions from Agricultural Soils, 1990-2003. Background Document on the Calculation Method for the Dutch National Inventory Repor written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Since 2005 the Dutch method to calculate the nitrous oxide emissions from agricultural soils has fully complied with the Intergovernmental Panel on Climate Change (IPCC) Good Practice Guidelines. In order to meet the commitments of the Convention on Climate Change and the Kyoto Protocol, nitrous oxide emissions have to be reported annually in the Dutch National Inventory Report (NIR). Countries are encouraged to use country-specific data rather than the default values provided by the IPCC. This report describes the calculation schemes and data sources used for nitrous oxide emissions from agricultural soils in the Netherlands. The nitrous oxide emissions, which contribute to the greenhouse effect, occur due to nitrification and denitrification processes. They include direct emissions from agricultural soils due to the application of animal manure and fertilizer nitrogen and the manure production in the meadow. Also included are indirect emissions resulting from the subsequent leaching of nitrate to ground water and surface waters, and from deposition of ammonia that had volatilized as a result of agricultural activities. Before 2005 indirect emissions in the Netherlands were calculated using a method that did not compare well with IPCC definitions and categories. The elaborate explanation here should facilitate reviewing by experts. Finally, the report also presents an overview of the nitrous oxide emissions from agricultural soils and the underlying data used in the 1990 - 2003 period.
Book Synopsis The effects of different mineral nitrogen fertilizer forms on N2O emissions from arable soils under aerobic conditions by : Jens Tierling
Download or read book The effects of different mineral nitrogen fertilizer forms on N2O emissions from arable soils under aerobic conditions written by Jens Tierling and published by Cuvillier Verlag. This book was released on 2017-05-02 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt: Intensively managed agricultural soils are a major source of the greenhouse gas nitrous oxide (N2O), mainly due to the use of mineral nitrogen fertilizers which stimulate microbial processes in soils that form N2O. While oxidized N fertilizer forms can be subject to denitrification, reduced N forms must first be oxidized by nitrification to become available for denitrification. Because the contribution of these processes to N2O emissions depends on the prevailing soil conditions, the choice of the N fertilizer form has the potential to mitigate N2O emissions from fertilized soils. The present study focused on comparing amid-, ammonium- and nitrate-based mineral fertilizers with regard to nitrogen transformation dynamics and N2O production under controlled as well as field conditions. For this two distinct methodological approaches to measure N2O emissions were evaluated and deployed. Furthermore, the effects of soil pH and the alkalizing hydrolysis of urea were investigated. It was shown that especially under aerobic conditions the N fertilizer form can significantly affect N2O production in soils, and that nitrite dynamics are important especially for nitrification-derived N2O emissions. Thus, the careful consideration of the N fertilizer form can be a measure to mitigate emissions from farmland.
Book Synopsis Nitrogen in Agricultural Systems by : James Stuart Schepers
Download or read book Nitrogen in Agricultural Systems written by James Stuart Schepers and published by ASA-CSSA-SSSA. This book was released on 2008 with total page 994 pages. Available in PDF, EPUB and Kindle. Book excerpt: Review of the principles and management implications related to nitrogen in the soil-plant-water system.
Book Synopsis Soil Contamination and Alternatives for Sustainable Development by : Dinora Vázquez-Luna
Download or read book Soil Contamination and Alternatives for Sustainable Development written by Dinora Vázquez-Luna and published by BoD – Books on Demand. This book was released on 2019-03-06 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book Soil Contamination and Alternatives for Sustainable Development allows the reader to obtain information about some case studies related to soil contamination, as well as provide sustainable alternatives to reduce environmental damage. The book is divided into two sections, where the first section describes anthropogenic contamination in detail and the second section discusses three alternatives for sustainable development.
Book Synopsis The Emissions of Nitrous Oxide from Agricultural Fields in New York State by : Marina Molodovskaya
Download or read book The Emissions of Nitrous Oxide from Agricultural Fields in New York State written by Marina Molodovskaya and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The atmospheric nitrous oxide (N2O) is of special interest, due to its persistent effect as a potent greenhouse gas and stratospheric ozone destructor. Animal manure fertilization is one of the key factors contributing to N2O formation. In the Northeastern US, dairy industry is the largest agricultural activity, and the manure cropland fertilization is a common practice. Continuous monitoring of N2O emissions from croplands in New York State was conducted by eddy covariance method from 2006 to 2009. The research was aimed at quantification of N2O emissions from manure-fertilized corn (Zea mays) and alfalfa (Medicago sativa) fields, estimating strength and spatial variability of soil N2O sources by conducting simultaneous static chamber campaign, and analysis of temporal distribution of N2O fluxes as affected by seasonality of climate variations and manure practices. The analysis of cumulative N2O emissions and source contributions into the integrated flux showed that manure nitrogen (N) was the most important factor controlling the extent of N2O formation: areas which received more manure N were stronger N2O emitters. Whereas N availability determined a magnitude of N2O emissions, the environmental changes altering soil moisture and temperature status were major N2O event triggers. The temporal flux distribution demonstrated episodic event-induced nature of N2O peak fluxes, which were primarily driven by strong rainfall and warm temperatures in growing season and soil thaw in winter and early spring. The greatest N2O emissions were observed when flux-triggering weather events coincided with or followed manure application. The most intense single N2O peak event was produced from combination of summer manure spreading and strong rainfall; however spring thaw-induced N2O fluxes showed more consistent seasonal year-to-year trend. The daily average fluxes measured by the EC and chamber techniques were in good agreement. The spatial variability of chamber measurements was mainly caused by high heterogeneity of soil N2O formation, which resulted both in net N2O production and consumption. The EC integrated flux was strongly dependent on wind direction and contributing footprint. The combination of the two different scale methods may help in reducing temporal and spatial variability of N2O estimates and improving N2O emission data quality. .
Book Synopsis Update of Emission Factors for Nitrous Oxide from Agricultural Soils on the Basis of Measurements in the Netherlands by : P.J. Kuikman
Download or read book Update of Emission Factors for Nitrous Oxide from Agricultural Soils on the Basis of Measurements in the Netherlands written by P.J. Kuikman and published by . This book was released on 2006 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Mitigation of Nitrous Oxide Emissions During Nitrification and Denitrification Processes in Agricultural Soils Using Enhanced Efficiency Fertilizers by : Yoshitaka Uchida
Download or read book Mitigation of Nitrous Oxide Emissions During Nitrification and Denitrification Processes in Agricultural Soils Using Enhanced Efficiency Fertilizers written by Yoshitaka Uchida and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Through the increasing use of nitrogen (N) fertilizers due to an increasing food demand, the agricultural sector is the main contributor of anthropogenic nitrous oxide (N2O) emissions, mainly through microbial processes called nitrification and denitrification. One option to mitigate N2O, a major greenhouse gas, is to use enhanced efficiency fertilizers (EEFs). There are different types of EEFs like nitrification inhibitors or controlled-release fertilizers that aim to match the N release from fertilizers with N demands from plants. Parts of the chapter are also dedicated to organic amendments and their effects on N2O emissions. Overall, EEFs can improve the N-use efficiency of plants, which has two positive effects. First, farmers can increase their yields, and second, environmental pollution through excessive fertilizer N can be minimized. However, the effectiveness of EEFs strongly depends on numerous factors like land use type, application method, and climate. More studies are needed to establish individual fertilizer plans that are optimized for the prevalent conditions. In conclusion, N2O mitigation using EEFs is only advisable when ,Äúinitial,Äù N2O emissions from conventional fertilizers are critically contributing to annual N2O emissions. Thus, careful assessment is needed before EEFs are introduced to the system especially when economic and ecologic results are considered.
Book Synopsis Effects of Management on Selected Soil Properties and Nitrous Oxide Fluxes in Dairy Cropping Systems by : Emily Paige Ball
Download or read book Effects of Management on Selected Soil Properties and Nitrous Oxide Fluxes in Dairy Cropping Systems written by Emily Paige Ball and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis investigates selected soil properties and management decisions and their effect on nitrous oxide (N2O) emissions from agricultural soils. Nitrate, an inorganic form of N, is extremely mobile in soils, making it susceptible to loss through processes like denitrification. Denitrification is an anaerobic microbial process that reduces nitrate to N2 or incompletely to N2O, a potent greenhouse gas. The experimental site for this research was the Sustainable Dairy Cropping System (SDCS) located at Penn States Agronomy Farm. Chapter one is a review of the literature on nitrogen (N) cycling in agriculture, N loss pathways and the management and environmental factors affecting denitrification. This process is driven by soil properties, nitrate availability, and other factors. A prior study in this experiment in 2015 and 2016 found that the driving factors for N2O emissions in some of the same treatments were explained by days after manure application, growing degree days (GDD), and manure rate.Research on the effects of prior crop and management on N2O emissions in a typical PA dairy cropping system is described in chapter two. Labile carbon, total carbon, inorganic N species, and other environmental data were measured to determine their impact on measured N2O fluxes in 2017 and 2018. However, the measured soil and environmental properties in this experiment were not able to explain the observed patterns in N2O emissions through a regression analysis. The highest N2O fluxes were measured in 2018 in Corn after two years of Alfalfa (Medicago sativa) + Orchardgrass (Dactylis glomerata). Cumulative emissions were more than six times higher than those measured in treatments without a winter cover in the same year.Based on findings in 2017, chapter three investigates the impact of termination timing of Alfalfa+Orchardgrass on spring N2O fluxes and soil properties in 2018. This management decision is becoming more popular in the Northeast as spring conditions become wetter, making the proper timing of spring management events difficult. The findings from this experiment are promising for farmers interested in adopting this management practice as yields did not significantly differ from the subsequent corn crop and although they did not significantly differ, spring cumulative emissions from the spring terminated treatment were more than three times those from the fall terminated treatment. Because N2O emissions were not measured in the fall, however, the comparison of the two treatments in this study was not comprehensive.Chapter four described an investigative study on redox potentials in unsaturated agricultural soils. Equipment constraints and spatial variability made understanding and interpreting these results difficult. There were diurnal trends exhibited in some treatments, reflecting diurnal changes in soil moisture but not others. There also seemed to be stratification in depth, although this trend also differed across treatments. Overall, there is evidence that different crops can facilitate different redox environments and in turn, different microbial processes. However, more research and equipment advances need to take place before redox potential could be considered a useful indicator of microbial processes in unsaturated soils.Finally, the conclusions summarized the major findings of each of these experiments and discussed the impact of sustainable management practices on improving soil resiliency. Implementing sustainable practices like cover cropping and no-till can improve soil, although trade-offs of higher N2O emissions may result. Further research on these practices and their impact on soil properties is necessary as the effects of climate change are becoming more apparent.
Book Synopsis The Effect Of Nitrogen Fertilizers On Some Meteorological Elements by : Mahmoud Amgad Saber
Download or read book The Effect Of Nitrogen Fertilizers On Some Meteorological Elements written by Mahmoud Amgad Saber and published by LAP Lambert Academic Publishing. This book was released on 2015-03-16 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Greenhouse gases (CO2 and N2O) play an important role in the atmospheric chemistry and in the global warming. According to the emissions inventories that governments submit to the UNFCCC, agriculture accounts for about 15 % of global GHGs. Agriculture contributes about half of the global emissions of two of the most potent non-carbon dioxide greenhouse gases nitrous oxide and methane. Nitrous oxide emissions from soils, fertilizers application and manures).Agricultural soils are considered sources of carbon dioxide emissions and nitrous oxide. The nitrogen fertilizer is the most important sources of nitrous oxide emissions.Clay soil fertilized with urea gave the largest amount of emissions of carbon dioxide and were15607 ppm, while in the control chambers were 9228 ppm (The proportion of clay soils contribute in the total emission amounted to 59.1% and was the carbon dioxide emitted by the urea ratio of 40.9%). Sandy soil fertilized with urea gave the highest emissions of nitrous oxide, where 6.07 ppm.In the first experiment we observe that the largest difference in temperature was 1.5 oC.In the second experiment also note that the largest difference in temperature was 1.73 oC .
