scholarly journals Evaluation of In-Season Nitrogen Management for Summer Maize in North Central China

ISRN Agronomy ◽  
2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
S.-C. Zhao ◽  
P. He ◽  
Z.-M. Sha ◽  
S.-L. Xing ◽  
K.-J. Li
Keyword(s):  
Field Experiments ◽  
Early Summer ◽  
Central China ◽  
Summer Maize ◽  
North Central ◽  
Grain Yields ◽  
Maize Growth ◽  
N Supply ◽  
N Management ◽  
N Rates

We conducted field experiments in which nitrogen (N) was applied to summer maize at different rates and different basal/topdressing ratios. The experiments were carried out in 2009 in Hengshui and Xinji, Hebei province, China. The results showed that basal application of N was necessary for maize growth in early summer and for high grain yields. For the Hengshui and Xinji sites, 30 and 57 kg N ha−1, respectively, would meet the N demands of maize before 7-leaf stage. The total rates of 120 and 180 kg N ha−1, respectively, would maximize grain yields, and in-season N management based on crop N demands and soil N supply could reduce N inputs by more than 50% in Hengshui and 25% in Xinji, respectively, in one maize growth season, compared with farmers' practice, but the sustainability of the optimum N rates for maximum grain yield of next seasons crop needs to be further studied. Optimum N management should take into account the existing nutrient conditions at each site, soil fertility and texture, and crop demands.

Recovery of 15N-labelled fertilizers applied to barley on two artificially eroded soils in north-central Alberta

1998 ◽  
Vol 78 (2) ◽  
pp. 377-383 ◽  
Author(s):  
R. Pradhan ◽  
R. C. Izaurralde ◽  
S. S. Malhi ◽  
M. Nyborg
Keyword(s):  
Field Experiments ◽  
Water Saturation ◽  
Nutrient Use Efficiency ◽  
N Loss ◽  
Hordeum Vulgare L ◽  
N Losses ◽  
North Central ◽  
Major Mechanism ◽  
Erosion Level ◽  
N Management

Soil erosion induces variability in soil properties which may influence nutrient use efficiency. A 2-yr field study was conducted with the following objectives: (1) to determine the recovery of 15N-labelled fertilizers applied to barley growing on artificially eroded soil, and (2) to compare N losses from nitrate- and ammonia-based N fertilizers. Field experiments were conducted in north-central Alberta in 1991 and 1992 on an Orthic Gray Luvisol (Site 1) and on an Eluviated Black Chernozem (Site 2) soil. At each site, a factorial experiment of three levels of artificial erosion (0, 10 and 20 cm) and three N sources (KNO3, urea, and control) was laid out as a split-plot design with four replications. The 15N-labelled fertilizers (5.63 atom % abundance) were banded in June 1991 at 150 kg N ha−1 within 46-cm by 46-cm steel frame microplots. The proportion of added N recovered by barley (Hordeum vulgare L.) was not affected by erosion level. Periodical water saturation and NO3− availability suggested denitrification as a major mechanism of N loss. The N losses ranged from 12 to 51 g N ha−1 in 1991 and 20 to 80 kg N ha−1 over the 2-yr period, but the N losses did not relate to erosion level. The N losses after 2 yr were greater from KNO3 than from urea at Site 1. Most of the added 15N was found in the surface 0- to 15-cm layer, but amounts of 15N were detected in the 15- to 30-cm or 30- to 45-cm layers. The results call for continued development of N management techniques geared to optimize crop growth and minimize losses from fields. Key words: Artificial erosion, barley, fate of applied N, 15N-labelled fertilizers, N immobilization, N loss

scholarly journals Using an Active Sensor to Develop New Critical Nitrogen Dilution Curve for Winter Wheat

Sensors ◽  
2020 ◽  
Vol 20 (6) ◽  
pp. 1577 ◽  
Author(s):  
Jie Jiang ◽  
Cuicun Wang ◽  
Yu Wang ◽  
Qiang Cao ◽  
Yongchao Tian ◽  
...  
Keyword(s):  
Winter Wheat ◽  
Field Experiments ◽  
Wheat Varieties ◽  
Active Sensor ◽  
Alternative Approach ◽  
Nitrogen Dilution ◽  
N Management ◽  
N Rates ◽  
Non Destructive ◽  
N Status

Critical nitrogen (N) dilution curves (CNDCs) have been developed to describe the dilution dynamic of N and to diagnose N status in plants. In this study, to develop a convenient alternative CNDC determination method, four field experiments involving different N rates (0–360 kg N ha-1) and six wheat varieties were performed at different eco-sites from 2014 to 2019. The normalised difference red-edge (NDRE) index extracted from the RapidSCAN CS-45 (Holland Scientific Inc., Lincoln, NE, USA) sensor was used as a driving factor instead of plant dry matter (PDM) to establish a new alternative winter wheat CNDC. The newly developed CNDC was described by the equation Nc = 0.90NDRE−0.88, when NDRE values were ≤ 0.19 and constant Nc = 3.81%, which was independent of the NDRE values. Compared to PDM-derived CNDC (R2 = 0.73) developed with the same dataset, a comparable precision was obtained using NDRE-derived CNDC (R2 = 0.76) and both CNDCs could accurately discriminate wheat N status. Moreover, the NDRE could be inexpensively and rapidly measured using the active sensor. The relationship between NDRE-derived CNDC and grain yield was also analysed to facilitate in-season N management, and the R2 value reached 0.79 and 0.87 at jointing and booting stages, respectively. The NDRE-based CNDC can be used to effectively diagnose wheat N status and as an alternative approach for non-destructive determination of crop N levels.

Assessment of the nitrogen status of onions (Allium cepa L.) cv. Cream Gold by plant analysis

1990 ◽  
Vol 30 (6) ◽  
pp. 853 ◽  
Author(s):  
NA Maier ◽  
AP Dahlenburg ◽  
TK Twigden
Keyword(s):  
Field Experiments ◽  
Soluble Solids ◽  
Marketable Yield ◽  
Total N ◽  
Scale Thickness ◽  
Plant Parts ◽  
N Supply ◽  
Nitrate N ◽  
Allium Cepa L ◽  
N Rates

Three field experiments were carried out during 1987-88 (1 site) and 1988-89 (2 sites) with Cream Gold onions grown on siliceous sands, to investigate the effect of nitrogen (N), at rates up to 475 kg N/ha on total-N, nitrate-N, potassium (K) and phosphorus (P) concentrations in youngest fully expanded blades (YFEB), bulked blades, necks and developing bulbs. The plant samples were collected when the largest bulbs were 25-30 mm in diameter. Nitrate-N concentrations were in the order WEB> bulked blades>necks = developing bulbs. For total-N the order was YFEB = bulked blades>necks> developing bulbs. Nitrate-N was more sensitive to variations in N supply than total-N in all tissues sampled. Potassium concentrations were in the order bulked blades > YFEB > necks > bulbs. At N rates <75 kg N/ha, P concentrations were in the order YFEB = bulked blades > bulbs > necks. Coefficients of determination (r2) for the relationships between nitrate-N and total-N concentrations and relative marketable yield of bulbs were in the range 0.73-0.98. At sites 1 and 3, the relationships between total-N and relative marketable yield were 'C-shaped' or showed the Piper-Steenbjerg effect. Critical concentrations (values at 90% relative marketable yield) for nitrate-N varied between plant parts (375-590 mg/kg) and sites (590-940 mg/kg for YFEB). Critical total-N concentrations also varied between the different plant parts (1.2-2.9%) but less so between sites (2.4-2.9% for YFEB) compared with nitrate-N. Based on sensitivity (as indicated by the range in tissue concentrations in response to variations in N supply) and on the correlations between nitrate-N and total-N concentrations and per cent relative marketable yield, we concluded that nitrate-N and total-N concentrations in YFEB were suitable indicators of the N status of onion plants. The YFEB is easily identified, and compared with bulked blades, necks or bulbs, samples of 50-100 can be collected without destroying plants and will also not result in excessive plant material to dry. Based on the variation in critical values between sites (reproducibility), total-N is preferred to nitrate-N. Correlations between nitrate-N and total-N concentrations in YFEB and bulb quality attributes (scale thickness, glucose concentration, fructose concentration, soluble solids and dry matter) were poor (72 values 10.48) and of little predictive value.

scholarly journals Use of Controlled-Release Urea to Improve Yield, Nitrogen Utilization, and Economic Return and Reduce Nitrogen Loss in Wheat-Maize Crop Rotations

Agronomy ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 723
Author(s):  
Xinpeng Xu ◽  
Ping He ◽  
Jianlin Wei ◽  
Rongzong Cui ◽  
Jingxia Sun ◽  
...  
Keyword(s):  
Economic Benefits ◽  
Central China ◽  
N Loss ◽  
Summer Maize ◽  
N Losses ◽  
Nitrogen Use ◽  
North Central ◽  
Use Efficiency ◽  
Net Benefits ◽  
Controlled Release Urea

Excessive nitrogen (N) fertilizer input has become a common phenomenon among most farmers in the winter wheat–summer maize rotation system of north-central China, and has resulted in low nutrient use efficiency and environmental pollution. Controlled-release urea (CRU) is proposed as a solution to excessive fertilization because CRU achieves high yields and reduces N losses. Therefore, CRU mixed with normal urea at rates based on the Nutrient Expert (NE) system was used as fertilizer in a 4-year field experiment to test the preference in crop yields, economic benefits, nitrogen use efficiencies, and N losses. The following fertilizer treatments were established: local farmers’ practices (FP); normal urea fertilizer at the rate recommended by the NE system (NE); mixed CRU and normal urea at ratios of 60:40 (CRU1) and 75:25 (CRU2) based on the NE system; and 80% of the recommended N rate of the NE, CRU1 and CRU2 treatments (80%NE, 80%CRU1 and 80%CRU2). The results showed that, compared with the NE treatment at the same application rate of N, mixed CRU and urea increased yields and net benefits while reducing N loss. The application of CRU at 60% for maize and 75% for wheat had the best overall effects. Compared with FP, the average grain yield, recovery efficiency of N fertilizer and net benefits increased by 8.5%, 10.9% and 11.3%, respectively, for maize with CRU1, and increased by 4.5%, 15.1% and 10.3%, respectively, for wheat with CRU2. Furthermore, mixed CRU and urea at the recommended N rate significantly reduced N loss from 38.5% to 40.3% but increased soil NO3−-N and NH4+-N contents at 0–30 cm, although opposite results (NO3−-N) were observed deeper in the soil (30–90 cm). In the treatments 80%CRU1 and 80%CRU2, the maize yield and overall economic benefits were equivalent to those in the FP treatment, but apparent N loss was significantly reduced. Thus, these results confirmed that the combination of the CRU and the NE system for winter wheat–summer maize in north-central China is efficient and valuable, and has the potential to improve yield, nitrogen use efficiency and net benefit with low N losses.

Nitrogen fixation and soil nitrate interactions in field-grown chickpea (Cicer arietinum) and fababean (Vicia faba)

2002 ◽  
Vol 53 (5) ◽  
pp. 599 ◽  
Author(s):  
J. E. Turpin ◽  
D. F. Herridge ◽  
M. J. Robertson
Keyword(s):  
Vicia Faba ◽  
Cicer Arietinum ◽  
N2 Fixation ◽  
Soil Nitrate ◽  
Soil N ◽  
Total N ◽  
Grain Yields ◽  
N Supply ◽  
Total Plant ◽  
N Rates

Soil in which nodulated legumes are growing often contains more nitrate nitrogen (N) than soil in which unnodulated legumes or non-legumes are growing. There is conjecture, however, as to whether the extra or ‘spared’ N is due to reduced use of soil N by the legume or to net mineralisation of legume root and nodular N. We report results of a field experiment to quantify and compare, at different levels of soil-N supply, N2 fixation, and soil-N use by chickpea (Cicer arietinum) and fababean (Vicia faba). Wheat (Triticum aestivum) was included as a non-N2-fixing control. Plants of the 3 species were grown on a low-nitrate Vertosol with fertiliser N rates of 0, 50, and 100 kg/ha (0N, 50N, and 100N), applied 6 weeks before sowing. Samples were collected at sowing and at 64, 100, 135, and 162 days after sowing (DAS) for analysis of soil nitrate, root, and grain dry matter (DM) and N and shoot DM, N, and 15N. The latter was used to estimate the percentage (%Ndfa) and total N fixed by the 2 legumes. Soil nitrate levels to a depth of 1.8 m at sowing were 11–17 kg N/ha (0N), 41–55 kg N/ha (50N), and 71–86 kg N/ha (100N). Grain yields of the 2 legumes were unaffected by soil-N supply (fertiliser N treatment), being 2.0–2.4 t/ha for chickpea and 3.7–4.6 t/ha for fababean. Wheat grain yields varied from 1.6 t/ha (0N) to 4.8 t/ha (100N). Fababean fixed more N than chickpea. Values (total plant including roots) were 209–275 kg/ha for fababean and 146–214 kg/ha for chickpea. Corresponding %Ndfa values were 69–88% (fababean) and 64–85% (chickpea). Early in crop growth, when soil N supply was high in the 100N treatment, fababean maintained a higher dependence on N2 fixation than chickpea (Ndfa of 45% v. 12%), fixed greater amounts of N (57 v. 16 kg/ha), and used substantially less soil N (69 v. 118 kg/ha). In this situation, soil N sparing was observed, with soil nitrate levels significantly higher in the fababean plots (P < 0.05) than under chickpea or wheat. At the end of growth season, however, there were no crop effects on soil nitrate levels. Soil N balances, which combined crop N fixed as inputs and grain N as outputs, were positive for the legumes, with ranges 80–135 kg N/ha for chickpea and 79–157 kg N/ha for fababean, and negative for wheat (–20 to –66 kg N/ha). We concluded that under the starting soil nitrate levels in this experiment, levels typical of many cropping soils in the region, high-biomass fababean and chickpea crops will not spare significant amounts of soil N. In situations of higher soil nitrate and/or smaller biomass crops with less N demand, nitrate sparing may occur, particularly with fababean.

A MESOZOIC RECORD OF FLUVIAL RESPONSE TO CLIMATIC AND TECTONIC PERTURBATIONS, ORDOS BASIN, NORTH-CENTRAL CHINA

2019 ◽  
Author(s):  
Chenliang Wu ◽  
◽  
Yuliang Duan ◽  
Trevor Cole ◽  
Jeffrey A. Nittrouer ◽  
...  
Keyword(s):  
Ordos Basin ◽  
Central China ◽  
North Central ◽  
Fluvial Response

Evaluation of the CERES-Rice Model for Precision Nitrogen Management for Rice in Northeast China

2017 ◽  
Vol 8 (2) ◽  
pp. 328-332
Author(s):  
J. Zhang ◽  
Y. Miao ◽  
W.D. Batchelor
Keyword(s):  
Northeast China ◽  
Weather Data ◽  
Cool Season ◽  
Use Efficiency ◽  
Optimum N Rate ◽  
Management Recommendations ◽  
N Management ◽  
N Rates ◽  
N Use

Over-application of nitrogen (N) in rice (Oryza sativaL.) production in China is common, leading to low N use efficiency (NUE) and high environmental risks. The objective of this work was to evaluate the ability of the CERES-Rice crop growth model to simulate N response in the cool climate of Northeast China, with the long term goal of using the model to develop optimum N management recommendations. Nitrogen experiments were conducted from 2011–2015 in Jiansanjiang, Heilongjiang Province in Northeast China. The CERES-Rice model was calibrated for 2014 and 2015 and evaluated for 2011 and 2013 experiments. Overall, the model gave good estimations of yield across N rates for the calibration years (R2=0.89) and evaluation years (R2=0.73). The calibrated model was then run using weather data from 2001–2015 for 20 different N rates to determine the N rate that maximized the long term marginal net return (MNR) for different N prices. The model results indicated that the optimum mean N rate was 120–130 kg N ha–1, but that the simulated optimum N rate varied each year, ranging from 100 to 200 kg N ha–1. Results of this study indicated that the CERES-Rice model was able to simulate cool season rice growth and provide estimates of optimum regional N rates that were consistent with field observations for the area.

The unusual recent streamflow declines in the Bailong River, north-central China, from a multi-century perspective

2021 ◽  
Vol 260 ◽  
pp. 106927
Author(s):  
Linlin Gao ◽  
Yang Deng ◽  
Xiaoya Yan ◽  
Qian Li ◽  
Yu Zhang ◽  
...  
Keyword(s):  
Central China ◽  
North Central

Genomic diversity of chickpea-nodulating rhizobia in Ningxia (north central China) and gene flow within symbiotic Mesorhizobium muleiense populations

2020 ◽  
Vol 43 (4) ◽  
pp. 126089 ◽  
Author(s):  
Junjie Zhang ◽  
Shanshan Peng ◽  
Yimin Shang ◽  
Brigitte Brunel ◽  
Shuo Li ◽  
...  
Keyword(s):  
Gene Flow ◽  
Genomic Diversity ◽  
Central China ◽  
North Central
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