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Background: Social media is a platform where people shares various information. Twitter is the most popular platform to share information about real-world events. The relevant information for people based on their interest in an event, attracts more and more public attention. The shared information could pertain to either local events (such as natural disasters, protests, or accidents) or global events (such as political events, wars, or international news with high impact). Objective: Event detection via tweets saves a lot of time to read thousands of tweets and informs users about the major events. Methods: This article proposes a graph modeling approach, which automatically extracts important information from tweets concerning local or global events. The proposed approach consists of three major components. The first component selects the candidate terms for an event using a modified Term Frequency-Inverse Document Frequency (TF-IDF) weighting scheme, which is suitable for Twitter dynamics. The second component proposes an event detection algorithm - Edge-Significance Based modified Louvain Algorithm (ESBLA), which clusters the event terms using modified Louvain algorithm. ESBLA improvise Louvain 1 through the utilization of significant edges. The last component detects the location of an event using the content-based technique. Results: The proposed approach is compared with existing approaches for the detection of events from tweets. The experimental results on labeled and real-time data show that the proposed approach is better than the compared approaches. Conclusion: The proposed event detection approach extracts events with a high degree of quality and run-time performance over the existing methods used for the event detection.

New Zealand's intensively grazed pastures receive the majority of nitrogen (N) input in the form of urea, which is the major constituent of animal urine and the most common form of mineral N in inorganic N fertilizers. In soil, urea is rapidly hydrolyzed to ammonium (NH4+) ions, a part of which may be lost as ammonia (NH3) and subsequently as nitrous oxide (N2O), which is a greenhouse gas. Two glasshouse experiments were conducted to study the effect of a urease inhibitor (UI), N-(n-butyl) thiophosphoric triamide (NBPT), commercially named Agrotain, applied with urine and urea on urea hydrolysis and NH3 and N2O emissions. Treatments included the commercially available products Sustain Yellow (urea + Agrotain + 4% sulfur coating), Sustain Green (urea + Agrotain) and urea, and cattle urine (476 kg N ha− 1) with and without Agrotain applied to intact soil cores of a fine sandy loam soil. The addition of Agrotain to urine and urea (i.e. Sustain Green) reduced NH3 emission by 22% to 47%, respectively. Agrotain was also effective in reducing N2O emissions from urine and Sustain Green by 62% and 48%, respectively. The reduction in N2O emissions varied with the type and amount of N applied and plant N uptake. Plant N uptake was significantly higher in the soil cores receiving Agrotain with urea than urea alone, but the slight increase in dry matter yield was non-significant. Hence, urease inhibitor reduced N losses through NH3 and N2O emissions, thereby increasing plant uptake of N. Refereed/Peer-reviewed

In New Zealand, urine deposited by grazing animals represents the largest source of nitrogen (N) losses, as gaseous emissions of ammonia (NH₃) and nitrous oxide (N₂O), and leaching of nitrate (NO₃⁻).We determined the effect of dicyandiamide (DCD) on gaseous emissions from pasture with increasing rates of urine-N application, mineral N transformations and potential leaching of N using undisturbed soil cores of Manawatu sandy loam at field capacity. The treatments included four levels of urine-N applied at 0 (control), 14.4, 29.0 and 57.0 g N/m² with and without DCD at 2.5 g/m². Results showed a significant (P < 0.05) increase in NH₃ and N₂O-N emissions as urine application was increased. The addition of DCD to corresponding urine treatments reduced N₂O emissions by 33, 56 and 80%, respectively. The addition of DCD with urine to the intact soil cores at field capacity moisture content resulted in a significant increase in the soil ammonium-N (NH₄⁺-N) concentration but little change in NH₃ emissions. Addition of DCD to urine reduced potential NO₃⁻-N leaching by 60–65% but potential NH₄⁺-N leaching increased by 2–3.5 times. There was no difference in pasture dry matter production with and without DCD treatments. Refereed/Peer-reviewed

The objective of this work was to study the degradation kinetics of a nitrification inhibitor (NI), dicyandiamide (DCD), and evaluate its effectiveness in reducing nitrous oxide (N2O) emissions in different types of soils. Three soils contrasting in texture, mineralogy, and organic carbon (C) content were incubated alone (control) or with urine at 600 mg N/kg soil with 3 levels of DCD (0, 10, and 20 mg/kg). Emissions of N2O and carbon dioxide (CO2) were measured during the 58-day incubation. Simultaneously, subsamples were collected periodically from the incubating soils (40-day incubation) and the amounts of DCD, NH4+, and NO3− were determined. Our results showed that the half-life of DCD in these laboratory incubating soils at 25°C was 6–15 days and was longer at the higher rate of DCD application. Of the 3 soils studied, DCD degradation was fastest in the brown loam allophanic soil (Typic orthic allophanic) and slowest in the silt loam non-allophanic soil (Argillic-fragic Perch-gley Pallic). The differences in DCD degradation among these soils can be attributed to the differences in the adsorption of DCD and in the microbial activities of the soils. Among the 3 soils the highest reduction in N2O emissions with DCD from the urine application was measured in the non-allophanic silt loam soil followed by non-allophanic sandy loam soil and allophanic brown loam soil. There was no adverse impact of DCD application on soil respiratory activity or microbial biomass.