scholarly journals The effects of the depth of fertilization on losses of nitrogen and phosphorus and soil fertility in the red paddy soil of China

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11347
Author(s):  
Kun Hou ◽  
Ying Huang ◽  
Xiangmin Rong ◽  
Jianwei Peng ◽  
Chang Tian ◽  
...  
Keyword(s):  
Paddy Soil ◽  
Ammonia Volatilization ◽  
Soil Column ◽  
Nitrogen And Phosphorus ◽  
Total N ◽  
Optimal Depth ◽  
Significant Difference ◽  
Research Objects ◽  
Minimal Environmental Impact ◽  
Red Paddy Soil

Nitrogen (N) and phosphorus (P) losses from agroecosystems are dominant nonpoint pollution. To minimize the losses of N and P, the optimal depth of fertilization was explored using a soil column study with the red paddy soil as the research objects. The losses of N and P were measured under five depths of fertilization (0, 5, 7.5, 10, and 12.5 cm) as well as no fertilization. The results showed that ammonia volatilization was significantly decreased with increasing fertilization depth within 0–10 cm, and there was no significant difference among the 10 cm, 12.5 cm, and no-fertilization treatments. Comparing with surface fertilization (0 cm), N and P losses by runoff could be reduced by 30.7–67.1% and 96.9–98.7% respectively by fertilization at 5–12.5 cm. In addition, deep fertilization (5–12.5 cm) did not increase N and P losses by leaching at the depth of 40 cm. Total N and P contents in the tillage layer of soil were increased by 5.1 to 22.8% and by −1.0 to 7.5%, respectively. Fertilization at 10cm depth has the potential to minimal environmental impact in the red paddy soil of south China, at this depth, NH3 volatilization was reduced by 95.1%, and N and P losses by runoff were reduced by 62.0% and 98.4%, respectively, compared with surface fertilization.

scholarly journals Evidence of Phosphate Mining and Agriculture Influence on Concentrations, Forms, and Ratios of Nitrogen and Phosphorus in a Florida River

Water ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1064
Author(s):  
Shuiwang Duan ◽  
Kamaljit Banger ◽  
Gurpal S. Toor
Keyword(s):  
Agricultural Land ◽  
Water Discharge ◽  
Mining Area ◽  
Specific Conductance ◽  
Organic N ◽  
Wet Season ◽  
Nitrogen And Phosphorus ◽  
Total N ◽  
Phosphate Mining ◽  
Molar Ratios

Florida has a long history of phosphate-mining, but less is known about how mining affects nutrient exports to coastal waters. Here, we investigated the transport of inorganic and organic forms of nitrogen (N) and phosphorus (P) over 23 sampling events during a wet season (June–September) in primary tributaries and mainstem of Alafia River that drains into the Tampa Bay Estuary. Results showed that a tributary draining the largest phosphate-mining area (South Prong) had less flashy peaks, and nutrients were more evenly exported relative to an adjacent tributary (North Prong), highlighting the effectiveness of the mining reclamation on stream hydrology. Tributaries draining > 10% phosphate-mining area had significantly higher specific conductance (SC), pH, dissolved reactive P (DRP), and total P (TP) than tributaries without phosphate-mining. Further, mean SC, pH, and particulate reactive P were positively correlated with the percent phosphate-mining area. As phosphate-mining occurred in the upper part of the watershed, the SC, pH, DRP, and TP concentrations increased downstream along the mainstem. For example, the upper watershed contributed 91% of TP compared to 59% water discharge to the Alafia River. In contrast to P, the highest concentrations of total N (TN), especially nitrate + nitrite (NOx–N) occurred in agricultural tributaries, where the mean NOx–N was positively correlated with the percent agricultural land. Dissolved organic N was dominant in all streamwaters and showed minor variability across sites. As a result of N depletion and P enrichment, the phosphate-mining tributaries had significantly lower molar ratios of TN:TP and NOx–N:DRP than other tributaries. Bi-weekly monitoring data showed consistent increases in SC and DRP and a decrease in NOx–N at the South Prong tributary (highest phosphate-mining area) throughout the wet season, and different responses of dissolved inorganic nutrients (negative) and particulate nutrients (positive) to water discharge. We conclude that (1) watersheds with active and reclaimed phosphate-mining and agriculture lands are important sources of streamwater P and N, respectively, and (2) elevated P inputs from the phosphate-mining areas altered the N:P ratios in streamwaters of the Alafia River.

Effect of biofertilizer and wheat straw biochar application on nitrous oxide emission and ammonia volatilization from paddy soil

2021 ◽  
Vol 275 ◽  
pp. 116640
Author(s):  
Haijun Sun ◽  
Yu Zhang ◽  
Yiting Yang ◽  
Yudong Chen ◽  
Paramsothy Jeyakumar ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Wheat Straw ◽  
Paddy Soil ◽  
Ammonia Volatilization ◽  
Nitrous Oxide Emission

scholarly journals Pain, Culture and Pedagogy: A Preliminary Investigation of Attitudes Towards “Reasonable” Pain Tolerance in the Grassroots Reproduction of a Culture of Risk

2021 ◽  
pp. 003329412098809
Author(s):  
Paul K. Miller ◽  
Sophie Van Der Zee ◽  
David Elliott
Keyword(s):  
Undergraduate Students ◽  
Pain Perception ◽  
Tertiary Education ◽  
Preliminary Investigation ◽  
Psychological Research ◽  
Pain Tolerance ◽  
Total N ◽  
Sporting Culture ◽  
Significant Difference ◽  
The Relationship

In recent years a considerable body of psychological research has explored the relationship between membership of socio-cultural groups and personal pain perception. Rather less systematic attention has, however, been accorded to how such group membership(s) might influence individual attitudes towards the pain of others. In this paper, immersion in the culture of competitive sport, widely regarded as being exaggeratedly tolerant of risky behaviours around pain, is taken as a case-in-point with students of Physical Education (PE) in tertiary education as the key focus. PE students are highly-immersed in competitive sporting culture both academically and (typically) practically, and also represent a key nexus of cross-generational transmission regarding the norms of sport itself. Their attitudes towards the pain that others should reasonably tolerate during a range of activities, sporting and otherwise, were evaluated through a direct comparison with those of peers much less immersed in competitive sporting culture. In total, N=301 (144 PE, 157 non-PE) undergraduate students in the UK responded to a vignette-based survey. Therein, all participants were required to rate the pain (on a standard 0-10 scale) at which a standardised “other” should desist engagement with a set of five defined sporting and non-sporting tasks, each with weak and strong task severities. Results indicated that PE students were significantly more likely to expect others to persevere through higher levels of pain than their non-PE peers, but only during the sport-related tasks – an effect further magnified when task severity was high. In other tasks, there was no significant difference between groups, or valence of the effect was actually reversed. It is argued that the findings underscore some extant knowledge about the relationship between acculturated attitudes to pain, while also having practical implications for understanding sport-based pedagogy, and its potentially problematic role in the ongoing reproduction of a “culture of risk.”

Automatic Registration for Navigation at the Anterior and Lateral Skull Base

2019 ◽  
Vol 128 (10) ◽  
pp. 894-902 ◽  
Author(s):  
Julia Kristin ◽  
Manuel Burggraf ◽  
Dirk Mucha ◽  
Christoph Malolepszy ◽  
Silvan Anderssohn ◽  
...  
Keyword(s):  
Skull Base ◽  
Navigation System ◽  
Automatic Registration ◽  
Total N ◽  
Electromagnetic Navigation ◽  
Registration Error ◽  
Target Registration Error ◽  
Lateral Skull Base ◽  
Significant Difference ◽  
Electromagnetic Navigation System

Objective: Navigation systems create a connection between imaging data and intraoperative situs, allowing the surgeon to consistently determine the location of instruments and patient anatomy during the surgical procedure. The best results regarding the target registration error (measurement uncertainty) are normally demonstrated using fiducials. This study aimed at investigating a new registration strategy for an electromagnetic navigation device. Methods: For evaluation of an electromagnetic navigation system and comparison of registration with screw markers and automatic registration, we are calculating the target registration error in the region of the paranasal sinuses/anterior and lateral skull base with the use of an electromagnetic navigation system and intraoperative digital volume tomography (cone-beam computed tomography). We carried out 10 registrations on a head model (total n = 150 measurements) and 10 registrations on 4 temporal bone specimens (total n = 160 measurements). Results: All in all, the automatic registration was easy to perform. For the models that were used, a significant difference between an automatic registration and the registration on fiducials was evident for just a limited number of screws. Furthermore, the observed differences varied in terms of the preferential registration procedure. Conclusion: The automatic registration strategy seems to be an alternative to the established methods in artificial and cadaver models of intraoperative scenarios. Using intraoperative imaging, there is an option to resort to this kind of registration as needed.

Effects of Long-Term Fertilization on the Distribution of Carbon, Nitrogen and Phosphorus in Water-Stable Aggregates in Paddy Soil

2011 ◽  
Vol 10 (12) ◽  
pp. 1932-1940 ◽  
Author(s):  
Wei WANG ◽  
Wei-cai CHEN ◽  
Kai-rong WANG ◽  
Xiao-li XIE ◽  
Chun-mei YIN ◽  
...  
Keyword(s):  
Paddy Soil ◽  
Nitrogen And Phosphorus ◽  
Water Stable Aggregates

Analysis of Ammonia Volatilization Loss from a Paddy Soil With Empirical and Mechanistic Models

2021 ◽  
pp. 2000230
Author(s):  
Wen‐Ming Xie ◽  
Pei‐Kun Yuan ◽  
You Ma ◽  
Wei‐Ming Shi ◽  
Hai‐Lin Zhang ◽  
...  
Keyword(s):  
Paddy Soil ◽  
Ammonia Volatilization ◽  
Mechanistic Models ◽  
Empirical And Mechanistic Models

Potassium Mobilization and Transformation in Red Paddy Soil as Affected by Rice

2014 ◽  
Vol 106 (3) ◽  
pp. 1011-1017 ◽  
Author(s):  
Xiaokun Li ◽  
Liping Zhan ◽  
Jianwei Lu ◽  
Zhiwen Liao ◽  
Jifu Li ◽  
...  
Keyword(s):  
Paddy Soil ◽  
Red Paddy Soil

scholarly journals CONSEQUENCES OF Cu and Zn COATED UREA TO MINIMIZE AMMONIA VOLATILIZATION

2016 ◽  
Vol 78 (6-12) ◽  
Author(s):  
Saima Kalsoom Babar ◽  
Mohd Khanif Yusop ◽  
Shakeel Ahmed Babar ◽  
Aijaz Ali Khooharo
Keyword(s):  
Ammonia Volatilization ◽  
N Uptake ◽  
Soil Series ◽  
Nh3 Volatilization ◽  
N Losses ◽  
Significant Difference ◽  
Coated Urea ◽  
Positive Effect ◽  
Range Test ◽  
Cu And Zn

Nitrogen (N) losses from agricultural fields are commonly observed particularly from urea. The rate of urea hydrolysis is accelerated as it remains in conventional form and about 70% of applied urea losses in different forms to atmosphere. Ammonia volatilization is persuasive loss among all the losses from urea. Therefore to minimize ammonia (NH3) volatilization the micronutrient coated urea is applied to enhance N-efficiency and its uptake. This study is an application of micronutrient coated urea with zinc (Zn) and copper (Cu) for two soil series of Malaysia. A laboratory experiment was designed according to the force draft technique for trapping the NH3 loss. The results have manifested that the rate of ammonia volatilization was 16% from uncoated urea and 8% from coated urea with micronutrients during the first two weeks of observations. After the six weeks of observations it was perceived that the ammonia losses for both soil series were gradually decreased with time. The mean comparison by using Tukey’s range test has shown the positive effect of micronutrient coated urea in comparison with the conventional urea. However the urea coated with the combination of both micronutrients Cu and Zn has shown significant difference in contrast to the coating urea with single micronutrient. The overall results revealed the efficacy of micronutrient coated urea on both of the soil series to maximize N-uptake and reduce NH3 volatilization.

scholarly journals Diurnal and spatial (vertical) dynamics of nutrients (N, P, Si) in four sampling days (summer, fall, winter, and spring) in a tropical shallow reservoir and their relationships with the phytoplankton community

2005 ◽  
Vol 65 (1) ◽  
pp. 141-157 ◽  
Author(s):  
J. J. Ramírez ◽  
C. E. M. Bicudo
Keyword(s):  
Phytoplankton Community ◽  
Southeastern Brazil ◽  
Nitrogen And Phosphorus ◽  
Vertical Variation ◽  
Total N ◽  
Phosphorus Forms ◽  
Reactive Silica ◽  
Photosynthetic Assimilation ◽  
The City ◽  
Total P

The vertical and diurnal variation of nitrogen and phosphorus forms, as well as that of soluble reactive silica (SRS), were studied in four sampling days at Garças reservoir, a shallow tropical one located in the city of São Paulo, in southeastern Brazil. Except for N-NH4, all other inorganic forms of nitrogen (N-NO2, N-NO3, and total N) demonstrated decreased concentrations toward the bottom of reservoir. Similarly, all showed significant diurnal differences on every sampling day, with increased values during the night due to absence of photosynthetic assimilation during that period. In the sampling days, these forms decreased on the spring sampling day due to the bloom of Microcystis registered during this period of the year. All three forms of phosphorus (SRP, particulate P, and total P) showed significant vertical variation, except on the fall sampling day. On the summer sampling day there was an increase of both total P and particulate P, the latter because it constitutes more than 70% of the total P during all sampling days. Hourly phosphorus variation was significant during all sampling days, except for the summer one. The SRS vertical variation was significant during all sampling days, except for that in the spring. It was also different hourly on sampling days.

Sign in / Sign up

Export Citation Format

Share Document