Use of climatic data for estimating nitrogen fertilizer requirements of dryland wheat

1989 ◽  
Vol 113 (2) ◽  
pp. 131-137 ◽  
Author(s):  
L. Korentajer ◽  
P. R. Berlinger ◽  
F. J. Dijkhus ◽  
J. Van Zyl

SUMMARYThe effect of moisture stress on N fertilizer needs of spring wheat (Triticum aestivum L.) was assessed using yield and meteorological data from N x P and N x P x K factorial trials, conducted on farmers' fields in a summer and a winter rainfall area in South Africa in 1979–84. Three to five rates of N fertilizer between 15 and 135 kg N/ha (plus control) and two to four replicates were used. The data were statistically analysed by a multiple regression yield model using applied N rate, N, and seasonal moisture stress, S, as the explanatory variables. A good positive correlation (r = 0.83, S.E. = 0.341 t/ha, D.F. = 48) was obtained between the estimated and the observed yields. The effects of S on Nmax and Novl (i.e. the N rates corresponding to maximum yield and an economically optimal rate, respectively), were evaluated. For 0.05 < S 7lt; 0.3, the range of S values representative of dryland cropping conditions, Nmax was largely independent of S, whereas Nopl increased sharply with decreasing S. The results indicated that N-response models which include moisture stress parameters may be used to determine the cropping areas climatically most suitable for wheat cultivation.

1994 ◽  
Vol 119 (3) ◽  
pp. 427-433 ◽  
Author(s):  
C.A. Sanchez ◽  
R.L. Roth ◽  
B.R. Gardner

Six field studies were conducted from 1980-88 to evaluate the response of cabbage (Brassica oleracea L., Capitata group) to sprinkler irrigation and sprinkler-applied N fertilizer on a coarse-textured soil. The plots were irrigated using a modified self-moving lateral sprinkler irrigation system that applied five levels of water and five levels of N (liquid NH4NO3) in specified combinations of central composite rotatable design. Cabbage yields were significantly increased by water and N applications in all experiments. The N rates predicted for maximum yield exceeded typical cabbage N fertilizer recommendations. However, the above-average plant populations used in these studies resulted in above-average yields and plant N accumulation. Deficit and excess irrigation produced negative results. Generally, cabbage production was optimized and N losses to the environment were minimized when crops were irrigated for evapotranspiration (ET) replacement. However, even when irrigated for ET replacement, these data demonstrate the potential for N leaching at high N rates, presumably as a result of rainfall.


2010 ◽  
Vol 90 (2) ◽  
pp. 179-184 ◽  
Author(s):  
C L Vera ◽  
S S Malhi ◽  
S M Phelps ◽  
W E May ◽  
E N Johnson

Industrial hemp (Cannabis sativa L.) has become a well-known crop in western Canada in recent years, but insufficient information is available on its nutrient requirements for optimum yield. Our objective was to confirm the response of two hemp cultivars to increasing levels of nitrogen (N), phosphorus (P) and sulphur (S) in various sites in the province of Saskatchewan, during 2006-2008. Increasing N rates significantly increased plant height, biomass, and seed yield, when data were averaged across all sites (location-years), reaching maximum values at about 150 kg N ha-1 of applied N fertilizer. The cultivar Crag was taller and produced greater biomass than the cultivar Finola over all levels of N fertilizer rate. The minimum rate of N fertilizer to achieve maximum height/biomass for Crag, relative to Finola, was 5 kg N ha-1 lower for height (Finola: 163 kg N ha-1) but 9 kg N ha-1 higher for biomass (Finola: 180 kg N ha-1). Finola seed yield was more responsive to progressively greater rates of N fertilizer. Consequently, maximum seed yield (plateau) was 27% greater for Finola than for Crag, but 198 kg N ha-1 of fertilizer was required to achieve this maximum yield vs. 175 kg N ha-1 for Crag. There was generally little or no response to P fertilizer, on soils with adequate available P, or to S fertilizer on an S-deficient soil. Results from this study indicate that N fertilizer rate and cultivar choice are important management parameters to consider for industrial hemp production.Key words: Fertilizer, hemp cultivars, nitrogen, phosphorus, sulphur, soil extractable P, soil nitrate-N


Agronomy ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2337
Author(s):  
Antoni Faber ◽  
Zuzanna Jarosz ◽  
Agnieszka Rutkowska ◽  
Tamara Jadczyszyn

Two 16-year-old series of experiments with winter wheat grown in rotation after winter oilseed rape were used in the study. The experiments were located in the cold temperate dry and moist climate zones on light soils. Wheat was fertilized with nitrogen in the doses of 40, 80, 120, 160, and 200 kg N·ha−1 per year. Through the several years of the experiment, critical N rates for maximum yield and gross margin from the linear-plus plateau regressions were 149 ± 23.9 and 112 ± 23.6 kg N·ha−1, respectively. The estimated nitrogen indicators for these doses were as follows: nitrogen use efficiency (NUE) 93 and 108%, N surplus (Ns) 6.8 and −10.1 kg·N·ha−1, yield-scaled Ns, N2O, and NH3 3.5 and −0.2; 0.35 and 0.30; 0.31 and 0.25 kg N·Mg−1, respectively. Experiments have shown that two strategies for reducing nitrogen losses on light soils under wheat cultivation are possible: by limiting the N dose to the critical values due to the yield requirements, or due to the gross margin. The analysis of the 11-year data for 2300 farm fields with winter wheat grown on light soils showed that only 10% of them were implementing the first strategy, and as much as 90% chose the second strategy.


Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 395
Author(s):  
Alex J. Lindsey ◽  
Adam W. Thoms ◽  
Marshall D. McDaniel ◽  
Nick E. Christians

Soil health and sustainable management practices have garnered much interest within the turfgrass industry. Among the many practices that enhance soil health and sustainability are applying soil additives to enhance soil biological activity and reducing nitrogen (N) inputs—complimentary practices. A two-year study was conducted to investigate if reduced N fertilizer rates applied with humic substances could provide comparable turfgrass quality as full N rates, and whether humic fertilizers would increase biological aspects of soil health (i.e., microbial biomass and activity). Treatments included synthetic fertilizer with black gypsum (SFBG), poly-coated humic-coated urea (PCHCU; two rates), urea + humic dispersing granules (HDG; two rates), urea, stabilized nitrogen, HDG, and a nontreated control. Reduced rates of N with humic substances maintained turfgrass quality and cover, and reduced clipping biomass compared to full N rates. There were no differences in soil physical and chemical properties besides soil sulfur (S) concentration. SFBG resulted in the highest soil S concentration. Fertilizer treatments had minimal effect on microbial biomass and other plant-available nutrients. However, PCHCU (full rate) increased potentially mineralizable carbon (PMC) and N (PMN) by 68% and 59%, respectively, compared to the nontreated control. Meanwhile SFBG and stabilized nitrogen also increased PMC and PMN by 77% and 50%, and 65% and 59%, respectively. Overall, applications of reduced N fertilizer rates with the addition of humic substances could be incorporated into a more sustainable and environmentally friendly turfgrass fertilizer program.


2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Changhyun Choi ◽  
Jeonghwan Kim ◽  
Jongsung Kim ◽  
Donghyun Kim ◽  
Younghye Bae ◽  
...  

Prediction models of heavy rain damage using machine learning based on big data were developed for the Seoul Capital Area in the Republic of Korea. We used data on the occurrence of heavy rain damage from 1994 to 2015 as dependent variables and weather big data as explanatory variables. The model was developed by applying machine learning techniques such as decision trees, bagging, random forests, and boosting. As a result of evaluating the prediction performance of each model, the AUC value of the boosting model using meteorological data from the past 1 to 4 days was the highest at 95.87% and was selected as the final model. By using the prediction model developed in this study to predict the occurrence of heavy rain damage for each administrative region, we can greatly reduce the damage through proactive disaster management.


2021 ◽  
Author(s):  
George Paschalidis ◽  
Ilias IIordanidis ◽  
Petros Anagnostopoulos

Abstract The purpose of this study is the evaluation of runoff and sediment transport in the basin of the Nestos River (Northern Greece) downstream of the dam of Platanovrisi, constructed in 1998. The model used for the simulation was AGNPS, which is based on the Revised Universal Soil Loss Equation (RUSLE), combined with a GIS interface. Two different simulations were conducted, one for the years 1980-1990 and another for the period 2006-2030, before and after the construction of the dam respectively. For the simulation for the period 1980-1990 existing meteorological data were employed, and the results were in good agreement with those of a different study (Hrissanthou, 2002). The simulation for the period 2006-2030 was based on rainfall and climatic data generated from the software packages GlimClim and ClimGen. The mean runoff was by 5% lower and the mean annual sediment yield by 20% lower than the corresponding values for the period 1980-1990.


2021 ◽  
Vol 32 ◽  
pp. 01007
Author(s):  
Ivan Prushchik ◽  
Svetlana Khlupina

The paper presents the results of research to assess the efficiency of winter wheat (Triticum aestivum L.) cultivation in adaptive crop rotations on typical chernozem. The crop yield have analyzed for three different crop rotations (grain-fallow, grain-grass-row, and grain-grass) in comparison with a monoculture on a stationary multifactorial field experiment on physical modeling of the farming system of the FSBSI “Kursk FARC” (Kursk region, Medvensky district). It was determined that the maximum yield was obtained in grain-and-row crop rotation; on average, over three years of research, the increase in it was 1.71 t/ha. Statistical data processing has carried out and correlations between the weather conditions of the year and the yield of winter wheat has revealed. Thus, a moderate direct relationship (r = 0.65) was established with atmospheric precipitation, and a moderate inverse relationship with the sum of effective temperatures (r = 0.58). Indicators of economic efficiency of winter wheat cultivation have calculated, both for monoculture and for three types of crop rotations. The lowest cost of winter wheat grain – 5926.94 t/ha – was recorded in grain-fallow crop rotation, which provided the highest net income of 12056.26 and the highest profitability among all options – 68.72%.


1963 ◽  
Vol 3 (9) ◽  
pp. 114 ◽  
Author(s):  
JD Colwell

The effects of the different sowing rates of 20, 40, and 60 lb of seed an acre on the yield, bushel weight, composition, and response to fertilizers, of wheat grown on soils of high fertility has been studied in seven field experiments in the wheat-belt of southern New South Wales. Seasonal conditions ranged from drought to lush growing conditions and in addition one experiment was irrigated to reduce the effects of moisture stress on plant growth. Yields ranged from 10 to 70 bushels of wheat an acre and fertilizer treatments gave both positive and negative effects. For the wide range of growth conditions, variation in seeding rate had only small and non-significant effects on grain yields, with the exception of the irrigated experiment where a consistent trend indicated the need for higher seeding rates for maximum yield. Effects of the seeding rates on grain size and composition and fertilizer response, were negligible. Losses in potential grain yield, caused by the exhaustion of soil moisture reserves by excessive vegetative growth of high fertility soils before grain development has been completed, does not seem to be reduced appreciably by the use of low seeding rates.


2019 ◽  
Vol 84 ◽  
pp. 01001
Author(s):  
Paweł Piotrowski ◽  
Dariusz Baczyński ◽  
Marcin Kopyt ◽  
Karolina Szafranek

The most important factor responsible for the quality of energy production forecasts in wind farms is the accurate wind speed forecast. An extensive statistical analysis of meteorological data (NWP) from 16 base nodes of the "300" grid in the "Łódź" area was made. The intention of the statistical analysis was to select potential explanatory variables for models predicting wind speed in the remaining 206 nodes of the grid’s mesh. Next, tests of selected prognostic methods were performed in order to compare their effectiveness with bilinear method which is not computationally complex. It should be emphasized that the main problem in spatial wind speed forecasting is the very large number of nodes for which the forecasts are calculated. As a consequence, more advanced and computationally complex forecasting methods cannot be applied in practice due to too long calculations time and difficulties in huge amounts of data processing. Conclusions with proposals of preferred forecasting methods that could be used in practice were developed.


2016 ◽  
Vol 155 (2) ◽  
pp. 261-281 ◽  
Author(s):  
S. E. ROQUES ◽  
D. R. KINDRED ◽  
S. CLARKE

SUMMARYTriticale has a reputation for performing well on poor soils, under drought and with reduced inputs, but there has been little investigation of its performance on the better yielding soils dominated by wheat production. The present paper reports 16 field experiments comparing wheat and triticale yield responses to nitrogen (N) fertilizer on high-yielding soils in the UK in harvest years 2009–2014. Each experiment included at least two wheat and at least two triticale varieties, grown at five or six N fertilizer rates from 0 to at least 260 kg N/ha. Linear plus exponential curves were fitted to describe the yield response to N and to calculate economically optimal N rates. Normal type curves with depletion were used to describe protein responses to N. Whole crop samples from selected treatments were taken prior to harvest to measure crop biomass, harvest index, crop N content and yield components. At commercial N rates, mean triticale yield was higher than the mean wheat yield at 13 out of 16 sites; the mean yield advantage of triticale was 0·53 t/ha in the first cereal position and 1·26 t/ha in the second cereal position. Optimal N requirement varied with variety at ten of the 16 sites, but there was no consistent difference between the optimal N rates of wheat and triticale. Triticale grain had lower protein content and lower specific weight than wheat grain. Triticale typically showed higher biomass and straw yields, lower harvest index and higher total N uptake than wheat. Consequently, triticale had higher N uptake efficiency and higher N use efficiency. Based on this study, current N fertilizer recommendations for triticale in the UK are too low, as are national statistics and expectations of triticale yields. The implications of these findings for arable cropping and cereals markets in the UK and Northern Europe are discussed, and the changes which would need to occur to allow triticale to fulfil a role in achieving sustainable intensification are explored.


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