scholarly journals Studies on Nitrate Nitrogen Contents in Forage Crops : I. Effects of Varying Levels of Nitrogen on Nitrate Nitrogen Contents in Some Forage Crops

1966 ◽  
Vol 34 (3) ◽  
pp. 292-297
Author(s):  
Kaoru EHARA ◽  
Yoshio YAMADA ◽  
Raizaburo UMETSU
1962 ◽  
Vol 59 (2) ◽  
pp. 205-206

The nitrate-nitrogen contents of herbage at the first cut of 1956, and at a first cut in 1957Herbage samples from two replicates of the first cut of 1956, and from two replicates of a first cut taken in 1957 in the present experiment, were analysed for nitrate-N. The 1957 results are included here as illustrating the influence of season on nitrate-N accumulation, although data from that year have not been reported in the two papers of the present series. Attention has been limited to first cuts, as nitrate-N accumulation is normally greater the shorter the interval between, the application of nitrogen fertilizer and sampling, and in addition the spring flush of growth is usually conducive to high nitrate-N contents (ap Griffith, 1961).


1961 ◽  
Vol 33 (1) ◽  
pp. 169-184
Author(s):  
Armi Kaila ◽  
Pentti Hänninen

The distribution of ammonium nitrogen and nitrate nitrogen in the soils of field trials was followed in two growing seasons. In these trials ammonium nitrate limestone and calcium nitrate were, at several rates, applied as surface dressing. It was found that not only the ammonium nitrogen but also the nitrate nitrogen applied to the surface of loam, silt, silt clay, and fine sand clay soils tended to remain in the top inch for a considerable period in the absence of heavy rainfalls or a longer wet period. The plants appeared rapidly to deplete the layers downwards from 1 inch, but even after six and eight weeks from the application of the fertilizers the ammonium nitrogen and nitrate nitrogen contents of the surface inch could be markedly higher in the treated plots than in the untreated ones. In the non-cropped soil, eight weeks after the application of the fertilizers, the mineral nitrogen content of the top inch corresponded to about 60 % of the nitrogen applied. On the basis of these results the working in or placement of nitrogen fertilizers seems to be profitable. Fixation of ammonium nitrogen in unexchangeable forms was observed in some of the trials. This, however, did not significantly impair the value of ammonium nitrate limestone as a nitrogen source in these trials.


1979 ◽  
Vol 59 (3) ◽  
pp. 839-846 ◽  
Author(s):  
S. P. GUERTIN ◽  
J. C. ST-PIERRE ◽  
P. GERVAIS

A 3-yr study on rates of nitgoren fertilization of timothy (Phleum pratense L.) showed that dry matter yield increased significantly with each increment of N fertilizer up to 448 kg/ha. Bounty outyielded Climax and Clair cultivars. Forage nutritive value index (NVI) was reduced by N fertilization but no significant difference was found among cultivars over the three growth cycles. Third cut forage had the highest and first cut forage the lowest NVI. Total, protein and non-protein nitrogen contents reached their highest values in first and second growth at highest rates of N fertilizer. Potentially toxic levels of nitrate-nitrogen were attained at each harvest only at rates of 448 and 896 kg/ha of N. On average over the season, Climax had the highest and Clair the lowest percentages of total and protein nitrogen while there was no significant difference among cultivars in the non-protein and nitrate nitrogen contents.


2012 ◽  
Vol 28 (1) ◽  
pp. 55-62 ◽  
Author(s):  
Beata Messyasz ◽  
Joanna Czerwik-Marcinkowska ◽  
Andreas Lücke ◽  
Bohuslav Uher

Abstract This paper presents the results of ultrastructural studies and ecological aspects of some phytoplankton species belonging to the groups of cyanobacteria (Planktothrix rubescens, Synechocystis aquatilis) and green algae (Desmodesmus grahneisii). Specimens were collected during summertime from the mesotrophic and stratified Lake Holzmaar (Western Germany) as planktonic forms from the pelagic zone. The highest cyanobacterium concentration was detected in the metalimnion, where the alkaline pH, low phosphorus and high nitrogen contents were recorded. P. rubescens was characterized by straight filaments up to 1000 μm long and 5.4-8 μm wide and numerous aerotopes in cells. The accompanying algae were identified by ultrastructural analysis and photographic documentation was provided. In the case of D. grahneisii, chloroplast was situated in the parietal part of cell, with one large, oval pyrenoid and, in addition, the granular and spiny cell wall was an important taxonomical criterium for the Desmodesmus genus. This is in contrast with the cyanobacterium S. aquatilis, in which a homogeneous content with visible chromatoplasma was mostly distributed throughout the cell. This algal association was stable in the epilimnion characterized by the presence of high temperature, pH values (>8), nitrate nitrogen and oxygen concentrations


1988 ◽  
Vol 59 (6) ◽  
pp. 563-564
Author(s):  
Junichi TAKAHASHI ◽  
Nobuyuki JOHCHI ◽  
Akio FUKUI ◽  
Hiroshi FUJITA

1956 ◽  
Vol 7 (3) ◽  
pp. 169 ◽  
Author(s):  
AE Martin ◽  
JE Cox

A study of the equilibrium levels of moisture, nitrate nitrogen, and ammonium nitrogen is reported on two representative black soils (developed from basaltic colluvium and alluvium respectively) from the Darling Downs for the years 1952-1954 inclusive. Both soils were under native grassland in 1952; a portion of the sampling area at each site was cultivated early in 1953 and left fallow for the rest of the sampling programme. The moisture contents of surface (0-6 in.) grassland and fallow plots varied directly with rainfall. Subsoil under grass showed low moisture contents which increased only after heavy rain but decreased thereafter, probably owing to transpiration. Under fallow, subsoil moisture was higher and showed significant fluctuations, suggesting that losses occurred by slow liquid flow or vapour movement a t moisture contents between field capacity and the wilting point. Ammonia-nitrogen contents at the surface were lower than for comparable soils in temperate regions and showed a significant decrease with depth; values for the corresponding fallow plots were similar in amount and varied similarly with depth. Surface soils showed minor fluctuations with season, being higher in summer. Under incubation conditions at 25°C, ammonia nitrogen rarely fell below 1.0 mg/kg oven-dry soil, which suggests that this is the minimum threshold concentration of ammonia nitrogen in these soils for the nitrification process. Nitrate nitrogen showed a significant rise in summer on the colluvial basaltic soil under grass. The soil developed on basaltic alluvium showed no such seasonal trend and contained uniformly low amounts of this fraction. Cultivation resulted in a sharp rise in nitrate nitrogen in both soils, the wetter alluvial soil showing a longer time lag. There was some evidence of nitrification in the 6-12 in. depth a t one site, but below this rises in nitrate nitrogen, which were correlated with rainfall and increases in moisture content, could be accounted for by leaching. Incubation tests gave rise to highly variable nitrate nitrogen contents and such tests were found unreliable in these soils, probably owing to imperfect aeration of the laboratory sample. Analyses for total nitrogen of several alluvial black soils from the same area showed a progressive decline in this constituent with increasing periods of cultivation; in the first 26 years of cultivation about 0.8 per cent. of the total nitrogen is lost per annum. This value agrees with the nitrate nitrogen accession in fallow subsoil, suggesting that leaching of nitrate formed at the surface is a major factor determining losses in total nitrogen. The implications of these findings are discussed.


Author(s):  
Akira SAKAMOTO ◽  
Hironari SUGIYAMA ◽  
Muneyuki NAKAGAWA ◽  
Isao TOMITA ◽  
Haruo KOREMOTO ◽  
...  

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