The Effect of Nitrate Nitrogen in the Soil Profile on the Response of Barley to Fertilizer Nitrogen

Soil moisture and nutrient variation within an undulating Manitoba landscape. Can. J. Soil Sci. 81: [449][450][451][452][453][454][455][456][457][458]. The use of discrete management units for variable-rate N fertilization requires that factors influencing grain yield response to N fertilizer are adequately characterized by delineating landscapes into such management units. The objective of this study was to compare the use of topographically derived landform element complexes (LEC) and the use of individual soil series as management units. Soil volumetric moisture content, nitrate-N, exchangeable ammonium-N, extractable phosphorus, exchangeable potassium, and sulphate-sulphur were studied in 10 intensively sampled transects in an undulating glacial till landscape near Miniota, Manitoba. The study site was delineated into upper, mid and lower LEC using a digital elevation model derived from relative elevation data. The LEC were useful in capturing gross variability at a manageable landscape scale. Among LEC there was a general trend of lower > mid > upper for median values of soil moisture, nitrate, phosphate, potassium and sulphate, as these attributes generally increased with convergent landscape character. Differences among LEC were often statistically significant, and relative distributions exhibited temporal persistence. The site was also stratified by soil series, including Newdale, Varcoe and Angusville soils (Black Chernozems), which were identified by examination of individual soil cores at each sample point. Stratifying the site into management units using soil genetic information, which is reflective of historical moisture conditions and biomass production, was expected to be superior. There was little advantage, however, in using soil series rather than LEC. Spatial distributions of the most agronomically relevant attributes (soil moisture and nitrate) were expressed at a landscape scale broader than that at which soil series occurred within the site. While there were important differences among soil series with respect to nutrients such as phosphate and sulphate, the site was better stratified by LEC with respect to soil moisture and nitrate. Pour fertiliser le sol avec une quantité variable d'engrais azoté, il est essentiel de bien caractériser les facteurs qui affectent la réaction du rendement grainier à l'engrais en divisant le terrain en unités agronomiques. L'étude devait comparer l'utilité de complexes d'éléments topographiques (CET) et de séries de sols comme unités agronomiques. Les auteurs ont déterminé la quantité d'eau, de N sous forme de nitrates ou d'ammonium échangeable, de phosphore extractible, de potassium échangeable et de soufre-sulfate dans un grand nombre d'échantillons prélevés le long de dix transects, sur un terrain de till glaciaire, près de Miniota, au Manitoba. Le site a été subdivisé en CET de haute, de moyenne et de faible altitude grâce à un système de modélisation numérique des hauteurs, à partir de la hauteur relative. Les CET permettent de saisir les variations gros...

Section: Residual Nitratementioning

confidence: 99%

Soil moisture and nutrient variation within an undulating Manitoba landscape

Manning¹,

Fuller²,

Eilers³

et al. 2001

“…Soil NO 3 -N tests have been developed to predict the amount of inorganic fertilizer N required to obtain optimum yield for many crops under a wide variety of climatic conditions (Hergert 1986). Soil NO 3 -N tests are used in western Canada and USA prior to planting to predict N requirements of wheat (Triticum aestivum L.) and corn (Zea mays L.) (Soper and Huang 1963;Dahnke and Johnson 1990). A midseason test is also used to determine the need for additional N fertilizer for corn (Sims et al 1995;Zebarth and Paul 1997).…”

Section: Mots Clésmentioning

confidence: 99%

Predicting nitrogen fertilizer requirements of potatoes in Atlantic Canada with soil nitrate determinations

Bélanger

Walsh²,

Richards³

et al. 2001

N. 2001. Predicting nitrogen fertilizer requirements of potatoes in Atlantic Canada with soil nitrate determinations. Can. J. Soil Sci. 81: 535-544. Nitrogen greatly affects potato (Solanum tuberosum L.) yield, but excess N can result in environmental degradation. In this study soil nitrate (NO 3 -N) content was determined pre-plant to predict fertilizer N requirements of potatoes in Atlantic Canada and in mid-season to adjust N fertilization during the growing season. Soil NO 3 -N contents were measured to a 0.30-m depth in spring prior to planting at four on-farm sites in each of 3 yr (1995 to 1997) in the upper St. John River Valley of New Brunswick, Canada. Mid-season soil NO 3 -N contents at a 0-0.30 m depth were also determined (32-47 days after planting) at two sites in three N treatments in 1995 (0, 50, and 250 kg N ha -1 ) and in four N treatments in 1996 and 1997 (0, 50, 100, and 250 kg N ha -1 ). The yield response of potatoes to six rates of N fertilization (0-250 kg N ha -1 ) with and without supplemental irrigation was used to determine the economically optimum N application (Nop). The pre-plant spring soil NO 3 -N test alone could not adequately predict the N requirements of potatoes in Atlantic Canada; the Nop and relative yield were poorly correlated (0.07 < R 2 < 0.52) with spring soil NO 3 -N content. The midseason soil NO 3 -N test, however, could be used to determine the need for supplemental N fertilizer; NO 3 -N content correlated well (0.44 < R 2 < 0.68) with the relative yield for total and marketable yield. We suggest a critical mid-season value of 80 mg NO 3 -N kg -1 soil for marketable yield, above which additional N application might not be necessary.Key words: N fertilizer, nitrate, Nop, relative yield, Solanum tuberosum, critical value Bélanger, G., Walsh, J. R., Richards, J. E., Milburn, P. H. et Ziadi, N. 2001. La prédiction des besoins en fertilisation azotée de la pomme de terre au Canada Atlantique avec les teneurs en nitrate des sols. Can. J. Soil Sci. 81: 535-544. L'azote (N) affecte beaucoup le rendement de la pomme de terre (Solanum tuberosum L.) mais l'excès de son utilisation peut causer une dégradation environnementale. Dans cette étude, la teneur du sol en nitrate (NO 3 -N) a été déterminée avant la plantation afin de prédire les besoins en N de la pomme de terre produite au Canada Atlantique et en milieu de saison afin d'ajuster la fertilisation au cours de la saison de croissance. La teneur du sol en nitrate a été mesurée au printemps à une profondeur de 0,30 m à quatre sites pendant trois années (1995 à 1997) dans la vallée de la rivière St-Jean au Nouveau-Brunswick, Canada. La teneur du sol en NO 3 -N à une profondeur de 0,30 m a aussi été déterminée 32-47 jours après la plantation (test de milieu de saison) à deux sites dans trois traitements en 1995 (0, 50, et 250 kg N ha -1 ) et dans quatre traitements en 1996 et 1997 (0, 50, 100, et 250 kg N ha -1 ). La réponse à la fertilisation azotée (0-250 kg N ha -1 ) avec ou sans irrigation supplémentaire a été utilisé...

“…To reduce N losses to the environment, new techniques for predicting fertilizer N requirements of crops are required. A test of soil NO 3 -N is a good direct measure of available N under hot and dry environments such as those in western Canada and the Great Plains of the United States of America (Soper and Huang 1963;Dahnke and Johnson 1990). Under the cold-humid environment of Atlantic Canada, a test of soil NO 3 -N might not work as well because mineralization of organic N supplies represents a significant portion of the total crop N requirements.…”

mentioning

confidence: 99%

Influence of previous cropping practices on the response of spring wheat to applied N

Bélanger¹,

Richards²,

Milburn³

et al. 1998

Influence of previous cropping practices on the response of spring wheat to applied N. Can. J. Soil Sci. 78: 267-273. Nitrate (NO 3 ) leaches from the rooting zone into ground waters during late fall and early spring in Atlantic Canada, particularly from soils cropped to potatoes, both in the year of potatoes and in the following year in the rotation. Therefore, it is imperative to maximize N fertilizer efficiencies in order to minimize environmental degradation. Six field trials were conducted in the upper St-John River Valley of New Brunswick to determine the effect of two previous crops, oats and potatoes, on the amount of residual NO 3 in the spring following their harvest, and to determine if spring soil NO 3 could be used as a single criterion to predict fertilizer N requirements of wheat. At all six field trials, spring soil NO 3 -N (0-0.45 m) was greater with potatoes as the previous crop (average of 86 kg NO 3 -N ha -1 ) than with oats (average of 56 kg NO 3 -N ha -1 ). As a result, the economically optimum fertilizer rate (Nop) for spring wheat was lower on soil previously cropped to potatoes (108 kg N ha -1 ) than oats (135 kg N ha -1 ). Nop, however, was poorly correlated with the amount of spring soil NO 3 -N. We conclude that conventional spring soil tests based on NO 3 -N are inappropriate to predict fertilizer N requirements of wheat in Atlantic Canada. Fertilizer N recommendations in Atlantic Canada, however, may be improved by taking previous crop into consideration.Key words: Wheat, potatoes, oats, nitrogen, previous crops Bélanger, G., Richards, J. E., Milburn, P. et Walker, D. 1998. Influence des pratiques culturales précédentes sur la réponse du blé de printemps à la fertilisation azotée. Can. J. Soil Sci. 78: 267-273. Les nitrates (NO 3 ) sont lessivés de la zone racinaire vers les eaux souterraines tard l'automne et tôt le printemps au Canada Atlantique, plus particulièrement sur les sols cultivés avec la pomme de terre, soit l'année de la culture de la pomme de terre ou l'année suivante. Il est donc impératif de maximiser l'efficacité de l'utilisation de l'azote de façon à minimiser la dégradation environnementale. Six essais au champ ont été réalisés dans le haut de la vallée de la rivière St-Jean au Nouveau-Brunswick pour déterminer l'effet de deux cultures précédentes, l'avoine et la pomme de terre, sur la quantité de nitrates résiduels le printemps suivant leur récolte, et pour déterminer si la teneur en NO 3 des sols au printemps pourrait être utilisée comme seul critère de prédiction des besoins en fertilisants azotés du blé de printemps. Sur les six essais au champ, la teneur en NO 3 des sols au printemps (0-0.45 m) était plus grande avec la pomme de terre comme culture précédente (moyenne de 86 kg NO 3 -N ha -1 ) qu'avec l'avoine (moyenne de 56 kg NO 3 -N ha -1 ). En conséquence, le taux de fertilisation économiquement optimum (Nop) pour le blé de printemps était plus bas sur les sols cultivés antérieurement avec la pomme de terre (108 kg N ha -1 ) que l'avoine (135 kg N ha -1 )....