scholarly journals Study on the Law of Nitrogen Transfer and Conversion and Use of Fertilizer Nitrogen in Paddy Fields under Water-Saving Irrigation Mode

Water ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 218 ◽  
Author(s):  
Menghua Xiao ◽  
Yuanyuan Li ◽  
Jianwen Wang ◽  
Xiujun Hu ◽  
Lei Wang ◽  
...  
Keyword(s):  
Nitrogen Uptake ◽  
Water Saving ◽  
Paddy Fields ◽  
Nitrogen Transfer ◽  
N Leaching ◽  
Nh3 Volatilization ◽  
Residual Rate ◽  
Fertilizer Nitrogen ◽  
Irrigation Technology ◽  
Leaching Loss

The research on the effect of water-saving irrigation technology on the loss of nutrients and chemical substances in farmland has become a hot issue in the field of agricultural water and soil. Based on comparative experiments and combined with the isotope N15 tracer technique, the mechanism of nitrogen migration and transformation and the trend of fertilizer nitrogen use under different irrigation modes were studied. The results showed that water-saving irrigation modes (thin and wet irrigation W1 and intermittent irrigation W2) could reduce the NO3−-N leaching loss by reducing the water leakage amount and the NO3−-N concentration, and effectively inhibit the leaching loss of fertilizer nitrogen. Compared with conventional irrigation (W0), the leaching loss amount of fertilizer nitrogen in W1 and W2 decreased by 62% and 64%, respectively. Under the same amount of fertilizer, water-saving irrigation mode can significantly reduce the total amount of ammonia (NH3) volatilization and the proportion of NH3 volatilization of fertilizer nitrogen in total NH3 volatilization, and significantly increase the nitrogen uptake of rice plants. Meanwhile, water-saving irrigation mode can increase the total nitrogen content of paddy soil by 14.0% but reduce the residual rate of fertilizer nitrogen in soil by 14.6%. Moreover, crop nitrogen uptake can be significantly increased under water-saving irrigation. Compared with W0, the nitrogen fertilizer use rate of W1 and W2 increased by 5.0% and 9.7%, respectively. The research results can provide an important basis for controlling agricultural non-point source pollution, curbing the decline of soil fertility and deterioration of soil quality in paddy fields.

scholarly journals Response of Vertical Migration and Leaching of Nitrogen in Percolation Water of Paddy Fields under Water-Saving Irrigation and Straw Return Conditions

Water ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 868 ◽  
Author(s):  
Chengxin Zheng ◽  
Zhanyu Zhang ◽  
Yunyu Wu ◽  
Richwell Mwiya
Keyword(s):  
Vertical Migration ◽  
Growth Stage ◽  
Nitrogen Leaching ◽  
Water Saving ◽  
Paddy Fields ◽  
N Leaching ◽  
Leaching Losses ◽  
Leaching Loss ◽  
Straw Return ◽  
Percolation Water

The use of water-saving irrigation techniques has been encouraged in rice fields in response to irrigation water scarcity. Straw return is an important means of straw reuse. However, the environmental impact of this technology, e.g., nitrogen leaching loss, must be further explored. A two-year (2017–2018) experiment was conducted to investigate the vertical migration and leaching of nitrogen in paddy fields under water-saving and straw return conditions. Treatments included traditional flood irrigation (FI) and two water-saving irrigation regimes: rain-catching and controlled irrigation (RC-CI) and drought planting with straw mulching (DP-SM). RC-CI and DP-SM both significantly decreased the irrigation input compared with FI. RC-CI increased the rice yield by 8.23%~12.26%, while DP-SM decreased it by 8.98%~15.24% compared with FI. NH4+-N was the main form of the nitrogen leaching loss in percolation water, occupying 49.06%~50.97% of TN leaching losses. The NH4+-N and TN concentration showed a decreasing trend from top to bottom in soil water of 0~54 cm depth, while the concentration of NO3−-N presented the opposite behavior. The TN and NH4+-N concentrations in percolation water of RC-CI during most of the rice growth stage were the highest among treatments in both years, and DP-SM showed a trend of decreasing TN and NH4+-N concentrations. The NO3−-N concentrations in percolation water showed a regular pattern of DP-SM > RC-CI > FI during most of the rice growth stage. RC-CI and DP-SM remarkably reduced the amount of N leaching losses compared to FI as a result of the significant decrease of percolation water volumes. The tillering and jointing-booting stages were the two critical periods of N leaching (accounted for 74.85%~86.26% of N leaching losses). Great promotion potential of RC-CI and DP-SM exists in the lower reaches of the Yangtze River, China, and DP-SM needs to be further optimized.

scholarly journals Effects of Biochar Amendment on CO2 Emissions from Paddy Fields under Water-Saving Irrigation

2018 ◽  
Vol 15 (11) ◽  
pp. 2580 ◽  
Author(s):  
Shihong Yang ◽  
Zewei Jiang ◽  
Xiao Sun ◽  
Jie Ding ◽  
Junzeng Xu
Keyword(s):  
Co2 Emissions ◽  
Rice Yield ◽  
Rice Paddy ◽  
C Sequestration ◽  
Sensitivity Coefficient ◽  
Water Saving ◽  
Paddy Fields ◽  
Flood Irrigation ◽  
Controlled Irrigation ◽  
Biochar Amendment

The role of carbon pool of biochar as a method of long-term C sequestration in global warming mitigation is unclear. A two-year field study was conducted to investigate the seasonal variations of CO2 emissions from water-saving irrigation paddy fields in response to biochar amendment and irrigation patterns. Three biochar treatments under water-saving irrigation and one biochar treatment under flooding irrigation were studied, and the application rates were 0, 20, 40, and 40 t ha−1 and labeled as CI + NB (controlled irrigation and none biochar added), CI + MB (controlled irrigation and medium biochar added), CI + HB (controlled irrigation and high biochar added), and FI + HB (flood irrigation and high biochar added), respectively. Results showed that biochar application at medium rates (20 t ha−1) decreased CO2 emissions by 1.64–8.83% in rice paddy fields under water-saving irrigation, compared with the non-amendment treatment. However, the CO2 emissions from paddy fields increased by 4.39–5.43% in the CI + HB treatment, compared with CI + NB. Furthermore, the mean CO2 emissions from paddy fields under water-saving irrigation decreased by 2.22% compared with flood irrigation under the same amount of biochar application (40 t ha−1). Biochar amendment increased rice yield and water use efficiency by 9.35–36.30% and 15.1–42.5%, respectively, when combined with water-saving irrigation. The CO2 emissions were reduced in the CI + MB treatment, which then increased rice yield. The CO2 emissions from paddy fields were positively correlated with temperature. The highest value of the temperature sensitivity coefficient (Q10) was derived for the CI + MB treatment. The Q10 was higher under water-saving irrigation compared with flooding irrigation.

scholarly journals Evaluation of Water-Storage and Water-Saving Potential for Paddy Fields in Gaoyou, China

Water ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 1176 ◽  
Author(s):  
Chuanjuan Wang ◽  
Shaoli Wang ◽  
Haorui Chen ◽  
Jiandong Wang ◽  
Yuan Tao ◽  
...  
Keyword(s):  
Southern China ◽  
Financial Burden ◽  
Water Shortage ◽  
Water Saving ◽  
Paddy Fields ◽  
Balance Model ◽  
Agricultural Water ◽  
Average Water ◽  
Agricultural Water Resources ◽  
Water Fee

In China, the stress on agricultural water resources is becoming increasingly severe. In response, a range of water-saving irrigation (WSI) policies and practices have been promoted to improve irrigation efficiency. In this study, a water-balance model in paddy fields was calibrated and validated using a 2-year field experimental dataset collected from an irrigated area in Gaoyou, China, in 2014–2015. The model was used to assess the effects of WSI practices and provides options for implementing water-price reforms. Results show that paddy fields effectively retain rainfall with utilization rates greater than 70% for both shallow wet irrigation (SWI) and shallow humidity-regulated irrigation (SHRI) scenarios. The estimated average water-saving rates from 1960 to 2015 using SWI and SHRI are 33.7% and 43%, respectively, which represent considerable reductions in water consumption. The benefits of WSI practices combined with water management policies are also evident. For example, conversion of irrigation water to industrial water yields a 3-year average water fee of 205.2 yuan/ha using SWI and 20.6 yuan/ha using SHRI, considerably reducing farmers’ financial burden for agricultural water supplies. In conclusion, we recommend the adoption of SWI and SHRI practices in southern China as a means of partially alleviating China’s water-shortage problem.

scholarly journals Perceptions of Irrigation Water Management Practices in the Mississippi Delta

Agronomy ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 186
Author(s):  
Carson Roberts ◽  
Drew M. Gholson ◽  
Nicolas Quintana-Ashwell ◽  
Gurpreet Kaur ◽  
Gurbir Singh ◽  
...  
Keyword(s):  
Water Management ◽  
Mississippi River ◽  
Irrigation Water ◽  
Management Practices ◽  
Mississippi Delta ◽  
Water Saving ◽  
Irrigation Water Management ◽  
Highly Efficient ◽  
Irrigation Technology ◽  
Over Time

The Mississippi River Valley Alluvial Aquifer (MRVAA) is being depleted, and practices that improve water stewardship have been developed to reduce drawdown. This study assesses how Mississippi Delta producers changed their perceptions of these practices over time. The analysis employs data from two surveys carried-out in 2012 and 2014 of all Mississippi permittees who held an agricultural well permit drawing from the MRVAA. Focusing on water-saving practices, this study found that producer perception of the usability of flowmeters improved over time. About 80% and 90% more producers growing corn and soybeans, respectively, felt that computerized hole selection was highly efficient. In 2014, 38% of corn and 35% of soybean producers believed that shortened furrow length was a highly efficient practice—up from 21% in corn and 24% in soybean producers in 2012. Approval of irrigation automation, moisture probes, and other irrigation technology rose from 75%of producers in 2012 to 88% by 2014. Favorability toward water-saving practices increased overall between the survey years.

Throughfall reduction diminished the enhancing effect of N addition on soil N leaching loss in an old, temperate forest

2020 ◽  
Vol 261 ◽  
pp. 114090 ◽  
Author(s):  
Shicong Geng ◽  
Zhijie Chen ◽  
Shanshan Ma ◽  
Yue Feng ◽  
Lei Zhang ◽  
...  
Keyword(s):  
Temperate Forest ◽  
N Leaching ◽  
Soil N ◽  
N Addition ◽  
Enhancing Effect ◽  
Leaching Loss ◽  
Throughfall Reduction

scholarly journals Comparison of Active Nitrogen Loss in Four Pathways on a Sloped Peanut Field with Red Soil in China under Conventional Fertilization Conditions

2019 ◽  
Vol 11 (22) ◽  
pp. 6219
Author(s):  
Zheng ◽  
Liu ◽  
Nie ◽  
Zuo ◽  
Wang
Keyword(s):  
Water Conservation ◽  
Nitrogen Loss ◽  
N2o Emission ◽  
Red Soil ◽  
N Leaching ◽  
Nh3 Volatilization ◽  
Leakage Loss ◽  
Active Nitrogen ◽  
Nitrogen Levels ◽  
Loss Rates

Active nitrogen loss mainly includes ammonia (NH3) volatilization, nitrous oxide (N2O) emission, NO3−-N and NH4+-N deep leakage (N leaching), and NO3−-N and NH4+-N surface runoff (N runoff), resulting in serious environmental problems. To analyze the characteristics of active nitrogen loss in the four pathways on sloped farmland under conventional fertilization, six lysimeters with a slope of 8° were used. Losses due to NH3 volatilization, N2O emission, N leaching, and N runoff were investigated after urea application on a peanut field with red soil in China during the growing season from 2017–2018. Results reveal that at conventional nitrogen levels of 150 and 172 kg hm−2, the total active nitrogen loss caused by fertilization accounting for the total nitrogen applied was 5.57% and 14.21%, respectively, with the N2O emission coefficients of 0.18% and 0.10%, respectively; the NH3 volatilization coefficients of 2.24% and 0.31%, respectively; the N leakage loss rates of 3.07% and 10.50%, respectively; and the N runoff loss rates of 0.08% and 3.30%, respectively. The dry year was dominated by leaching and NH3 volatilization, while the wet year was dominated by leaching and runoff; the base fertilizer period was dominated by leakage, while the topdressing period was dominated by leakage and runoff, which suggests that the loss of active nitrogen in the soil-peanut system on a sloped red soil was mainly affected by rainfall and fertilization methods. Taken together, reasonable fertilization management and soil and water conservation measures appear to be effective in minimizing the loss of active nitrogen from nitrogen fertilizer.

Isotopic studies on the uptake of nitrogen by pasture grasses. II. Uptake of fertilizer nitrogen by Rhodes grass in posts

1964 ◽  
Vol 15 (6) ◽  
pp. 876 ◽  
Author(s):  
EF Henzell ◽  
AE Martin ◽  
PJ Ross ◽  
KP Haydock
Keyword(s):  
Linear Function ◽  
Total Nitrogen ◽  
Nitrogen Uptake ◽  
Nitrogen Fertilizer ◽  
Rhodes Grass ◽  
Fertilizer Nitrogen ◽  
Pasture Grasses ◽  
Isotopic Studies ◽  
Pretreatment Phase

Nitrogen uptake by Rhodes grass was a linear function of the quantity of 15NH4N03 applied for rates up to the equivalent of 400 lb N/ac, but the proportion of fertilizer nitrogen recovered in the plants fell significantly when the rate was increased to 800 lb N/ac. A nitrogen pretreatment equivalent to 200 lb N/ac had relatively little effect on the uptake of 15NH4N03 by the grass, despite the fact that it almost doubled the weight of roots in the pots when the 15NH4N03 was first applied. Over the range 0–400 lb N/ac, 84.1%% of added total nitrogen and 75.5% of added 15N was taken up by plants that received no nitrogen fertilizer during the pretreatment phase, and 80.3% of added total nitrogen and 71.9% of added 15N was taken up by plants that received a pretreatment of 200 lb N/ac. Fertilizer nitrogen was distributed between tops and roots in the ratio (averaged for the two pretreatments) of 5.2 : 1 for total nitrogen and 4.5 : 1 for 15N; these ratios were constant over the range 0–400 lb N/ac and were not significantly different.

Sign in / Sign up

Export Citation Format

Share Document