scholarly journals Peat as a source of nitrogen for plants in pot culture

1958 ◽  
Vol 30 (1) ◽  
pp. 223-232
Author(s):  
Erkki Kivinen ◽  
Armi Kaila
Keyword(s):  
Ammonium Nitrogen ◽  
Mineral Nitrogen ◽  
Pot Experiment ◽  
First Year ◽  
Pot Experiments ◽  
Incubation Experiments ◽  
Phosphorus Fertilizers ◽  
Short Time ◽  
Pot Culture

Results are reported of a pot experiment in which four successive oat crops were grown with peat as the only source of nitrogen. Eight samples from virgin peat lands representing different land qualities were used. The samples were air-dried and ground which is known to increase markedly the amount of ammonium nitrogen in peat. Some data from incubation experiments were compared with the uptake of peat nitrogen by plants. The results did not agree with the earlier conception that the Carex-peats are superior to the Sphagnum-peats, particularly in regard to the availability of peat nitrogen. Under the conditions of pot culture and incubation experiments some of the fairly poor Carex-Sphagnum peats were markedly better as supplyers of nitrogen to the plants than were e.g. samples of Bryales-Carex peat and eutrophic Sphagnum-Carex peat of the present study. The uptake of nitrogen by plants from the peat samples was often lower than the amounts of mineral nitrogen accumulated in short-time incubation experiments. The possible reasons for this discrepance was discussed. It was pointed out that in pot experiments these air-dried and ground peat proved to produce higher yields without phosphorus fertilizers than without application of nitrogen, at least in the first year.

scholarly journals Influence of lime on the accumulation of mineral nitrogen in incubation experiments of peat soils

1957 ◽  
Vol 29 (1) ◽  
pp. 229-237
Author(s):  
Armi Kaila ◽  
Sylvi Soini
Keyword(s):  
Nitrate Nitrogen ◽  
Nitrogen Nutrition ◽  
Ammonium Nitrogen ◽  
Mineral Nitrogen ◽  
Peat Soils ◽  
Prolonged Incubation ◽  
The Third ◽  
Nitrite Nitrogen ◽  
Incubation Experiments ◽  
Three Samples

In the present paper the effect of lime on the mobilization of peat nitrogen was studied using incubation experiments under laboratory conditions. In the first experiment in which 13 samples of virgin peat soils were incubated for four months at 7°C, lime caused a marked nitrification of ammonium nitrogen in three samples, and a fairly low increase in the ammonium nitrogen content of five samples. The accumulation of total mineral nitrogen was benefited by lime in five samples and only in one of them could a marked increase be detected. In the second experiment the amounts of lime applied to five peat samples corresponded to 4000, 8000 or 12 000 kg/ha of CaCO3. At the end of an incubation period of four months at 9—15°C the total amounts of mineral nitrogen accumulated did not depend on the fate of liming, as did the nitrification in SCp-and BCp-samples, and also, in part, in the Sp- and CSp-samples. After the prolonged incubation up to 12 months the amount of lime applied had little or no effect upon the accumulation of nitrate-nitrogen or total mineral nitrogen except in the SCp-sample in which a positive correlation between these figures existed. Traces of nitrite-nitrogen were detected in some of the samples incubated for four months with the heaviest applications of lime. In the third experiment carried out at 7°C the treatment with lime was equal to that in the second series, but half of the pots were treated with ammonium nitrate corresponding to 100 kg/ha of nitrogen. The effect of lime on the treated samples appeared to be similar to that in the untreated one. Owing to the large variation, the fate of applied mineral nitrogen could not be distinctly detected. The loss of ammonium nitrogen through volatilization from the most heavily limed pots may be a possible explanation for the lower amounts of total mineral nitrogen in the incubated BCp-samples. Some reasons for these variable results are discussed and attention is also paid to the importance of nitrification on the nitrogen nutrition of plants.

scholarly journals Influence of lime and fertilizers upon the mineralization of peat nitrogen in incubation experiments

1954 ◽  
Vol 26 (1) ◽  
pp. 79-95 ◽  
Author(s):  
Armi Kaila ◽  
Sylvi Soini ◽  
Erkki Kivinen
Keyword(s):  
Ammonium Nitrogen ◽  
Ammonium Molybdate ◽  
Mineral Nitrogen ◽  
Nitrogen Fertilizers ◽  
Prolonged Incubation ◽  
Incubation Experiments ◽  
Low Degree ◽  
Sphagnum Fuscum ◽  
Effect Of Copper ◽  
Different Origins

An attempt has been made to elucidate the influence of lime and fertilizers upon the mineralization of peat nitrogen under laboratory conditions. The main object was to study differences between the responce of various kinds of peats to these treatments and to the incubation under conditions favourable for the activity of microorganisms. The material consisted of eight peat samples from North Finland. Four of them were fen peats with a virgin productivity of 6—8. The other four originated from untillable bogs with a virgin productivity of 1—3. All the samples were from virgin peat lands and only slightly decomposed. In spite of the different origins of these peat groups no marked differences in their chemical composition and characteristics could be found. This was supposed to be due to their low degree of decomposition. In the first large incubation experiment carried out at 15°—22 °C the accumulation of nitrate-nitrogen during the B—lo8—10 months of incubation was relatively high in all the limed samples, but marked nitrification occurred also in most of the un-limed samples, the Sphagnum fuscum peat being the most prominent exception. On the average, the effect of lime upon the total accumulation of mineral nitrogen was positive only in three of the fen peats and in the Sphagnum fuscum sample. In the second experiment lime seemed to stimulate the ammonification in the Sphagnum peats during the first month of incubation, but later on the accumulation of mineral nitrogen was found to be almost equally intensive in the limed and un-limed samples. No significant effect of potassium, phosphorus and nitrogen fertilizers could be stated in the incubation experiments. The same was true in respect to the effect of copper sulphate, zinc chloride or ammonium molybdate. The influence of ash upon the changes in the mineral nitrogen content of one fen peat was supposed to be due to its neutralizing agencies. The accumulation of mineral nitrogen, particularly of ammonium nitrogen, was highest in the untreated samples. Although some superiority of the fen peats to the Sphagnum peats in respect to the speed of the accumulation of mineral nitrogen could be stated, the differences between these groups after the prolonged incubation were negligible. This can be explained by the different intensity of immobilization and denitrification of nitrogen in these peats under the conditions of the experiments. It also may be taken to mean that no distinct differences existed between the decomposability of the nitrogen compounds of these slightly humified fen peats and Sphagnum peats.

scholarly journals Defence Is a Priority in Female Juveniles and Adults of Taxus baccata L.

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 844
Author(s):  
Kinga Nowak ◽  
Marian J. Giertych ◽  
Emilia Pers-Kamczyc ◽  
Peter A. Thomas ◽  
Grzegorz Iszkuło
Keyword(s):  
Starch Content ◽  
Pollen Grains ◽  
Pot Experiment ◽  
Total Phenolic ◽  
First Year ◽  
Specific Response ◽  
Taxus Baccata ◽  
Dioecious Plants ◽  
A Priority ◽  
Sexually Mature

Female individuals of dioecious plants invest their resources more in storage and defence, and the males have higher nitrogen content invested in the production of pollen grains. An unresolved problem is whether this strategy occurs only in sexually mature plants or can also occur in juvenile plants. To answer this, Taxus baccata (L.) needles from the mature plants and rooted cuttings (juveniles) in a pot experiment were compared for the content of carbon, nitrogen, starch, total non-structural carbohydrates (TNC), and total phenolic compounds (TPhC). The results indicate that the differences between sexes occurred mainly in sexually mature plants, where the starch content was higher in females and nitrogen in males. However, the novelty of the results is that TPhC was generally higher in females than males in both adults and juveniles, suggesting that defence is a priority for females from an early age. We do not know if this is an innate trait because the strobili production (albeit at a very low level) of juveniles was observed in all individuals after the autumn of the first year. We found no effect of fertilization on sex-specific response in the pot experiment, which may be related to the lower reproductive effort of juveniles.

scholarly journals Dynamics of mineral nitrogen in the gray forest soil under malt barley on the background of mineral fertilizers in the forest steppe of the east Prisayan

2021 ◽  
Vol 285 ◽  
pp. 06005
Author(s):  
Viktor Grebenshchikov ◽  
Nikolay Tyutrin ◽  
Vasily Verkhoturov
Keyword(s):  
Forest Soil ◽  
Field Experiments ◽  
Gray Forest Soil ◽  
Heavy Particle ◽  
Vegetation Period ◽  
Ammonium Nitrogen ◽  
Mineral Nitrogen ◽  
Mineral Fertilizers ◽  
Forest Steppe ◽  
Moisture Regime

The content of mineral nitrogen was studied when it was applied at a dose of 60 kg / ha on gray forest soil of heavy particle- size distribution at various levels of phosphorus-potassium nutrition in field experiments with barley. Fertilizer doses were determined by the normative method according to the CINAS method for a planned yield of 3 t / ha. It was shown that the dynamics of nitrate and ammonium nitrogen depended on the moisture regime during the vegetation period. With excessive moisture, nitrate nitrogen, with its initial content of 4-5 mg / kg, is not detected in the arable layer by the middle of the growing season, and with a moisture deficit, less dynamism is noted. It is found in an amount of 5-7 mg / kg by the end of vegetation. The N – NH4 + dynamics turned out to be less pronounced. With an excess of moisture, its content increased to 15.6 mg / kg, and with a deficit, it decreased more than by four times from the maximum during the vegetation. In general, the content of mineral nitrogen in gray forest soil is highly dynamic, which depends on the moisture regime and the nature of its consumption by barley.

scholarly journals Observations on the mobilization of peat nitrogen in incubation experiments

1959 ◽  
Vol 31 (1) ◽  
pp. 268-281
Author(s):  
Jaakko Kivekäs ◽  
Erkki Kivinen
Keyword(s):  
Nitrate Nitrogen ◽  
Ammonium Nitrogen ◽  
The Other ◽  
Incubation Experiments ◽  
Different Types ◽  
Working Out ◽  
Original Amount

60 peat samples from northern Finland representing different types of peat were incubated in a laboratory at a temperature of 17—18° C. The ammonium nitrogen, the nitrate nitrogen and the pH in the samples were determined after one month of incubation as well as after three months of incubation. The results were compared to results from determinations made before incubation. An attempt was made to elucidate the factors that influence the mobilization of nitrogen. On the basis of the above results it is evident that the differences between the various peat types as mobilizers of nitrogen are under these circumstances not very distinct, nor do these differences seem to be dependent on the types of peat. The following facts can, however, be established: In the amounts of ammonium nitrogen an increase takes place in most groups of samples during the first month. This increase is fairly big in the Sphagnum-dominated peats. The increase in ammonium nitrogen continues in the unlimed samples in most peat groups during all three months of incubation. After three months of incubation the amount of ammonium nitrogen in the limed samples is smaller than in the unlimed samples, although it is usually bigger than in the original samples. After the first month of incubation the amounts of nitrate nitrogen in all types of peat have decreased compared to the amounts in the original samples. In the limed samples the decrease is not as great as in the unlimed ones. After three months of incubation the amount of nitrate nitrogen has considerably increased as compared to the amount after one month of incubation. In the limed samples it might to some extent exceed the original amount of nitrate nitrogen, however, this is seldom the case in the unlimed samples. If the results are calculated on the basis of weight unit, it can be stated that the ability to mobilize nitrogen is greater in the Sphagnum peats than in the other peat groups. Working out the results in kg per ha it will be noted that somewhat more nitrogen is mobilized in the Carex-dominated than in the Sphagnum-dominated peats. The results obtained by experiments in the laboratory are not directly applicable to conditions in the field.

Image selection in static telepathology through the Internet

1998 ◽  
Vol 4 (1_suppl) ◽  
pp. 20-22 ◽  
Author(s):  
V Della Mea ◽  
P Cataldi ◽  
S Boi ◽  
N Finato ◽  
P Dalla Palma ◽  
...  
Keyword(s):  
Frozen Section ◽  
Definitive Diagnosis ◽  
Acquisition Time ◽  
The Internet ◽  
First Year ◽  
Remote Diagnosis ◽  
Diagnostic Agreement ◽  
Diagnostic Work ◽  
Short Time

A telepathology study was carried out to examine the differences occurring when the images were selected by an experienced pathologist, a junior pathologist and a first-year resident. One hundred and fifty-five consecutive frozen-section pathology cases were collected and sent for consultation to a remote experienced pathologist using multimedia email. Local diagnoses (as reported in the files of the Institute, not from the image selector) and remote diagnoses (based on the images) were compared with those performed on paraffin-embedded sections. Acquisition time and number of selected images were recorded for each case and used to compare the different behaviour of the three local pathologists. Of the 155 cases sent by telepathology, four were considered insufficient for a diagnosis by the remote pathologist and thus the diagnosis was postponed. In the remaining 151 cases, the overall diagnostic agreement between remote and definitive diagnosis was 96.7%. The results indicate that in the routine diagnostic work of a frozen-section service, an inexperienced pathologist can select images which are sufficiently informative for a remote diagnosis, in a sufficiently short time.

scholarly journals George Barker Jeffery, 1891-1957

1958 ◽  
Vol 4 ◽  
pp. 128-137 ◽  
Keyword(s):  
Military Service ◽  
Royal Society ◽  
Applied Mathematics ◽  
London Mathematical Society ◽  
First Year ◽  
Conscientious Objector ◽  
Active Service ◽  
University College ◽  
University College London ◽  
Short Time

George Barker Jeffery was born on 9 May 1891. He came from a Quaker family, and remained a Quaker all his life. He was educated at Strand School, King’s College, and Wilson’s Grammar School, Camberwell. In 1909 he entered University College, London, to begin a course, common at that time, of two years at the college to be followed by one year’s training as a teacher. He was not an entrance scholar, but his work in mathematics showed so much promise that he was elected to a scholarship in mathematics at the end of his first year. In 1911 he entered the London Day Training College for his teacher’s training. It was there that he met Elizabeth Schofield, whom he married in 1915. However he had already commenced mathematical research, and he read his first paper (1)* before the Royal Society in June 1912, the month following his twenty-first birthday. His later career showed how great an impression had been made upon him by his year’s training as a teacher. However, after it was over he returned to University College as a research student and assistant to L. N. G. Filon, who was then Professor of Applied Mathematics. He always had a great admiration for Filon, though this was not uncritical, as is shown by the obituary notices which he later wrote for the Royal Society, the London Mathematical Society and the Mathematical Association. In 1914 Filon went away on active service, and Jeffery, aged 23, was left in charge of the Department of Applied Mathematics. In 1916 he was elected a Fellow of University College. However, as a Quaker he had a conscientious objection to performing military service, so that he could not do this, nor was he allowed to remain at the college. In 1916 he spent a short time in prison as a ‘conscientious objector’, though later he was allowed to undertake ‘work of national importance’. In 1919, when the war was over, he returned to the college, again as an assistant to Filon. In spite of all the difficulties of the war period he had, as the list of his publications shows, maintained a steady output of original work. In 1921 he was promoted to the grade of University Reader in Mathematics.

Mineral nitrogen in soils undergoing irrigated rice-upland crop rotations

1980 ◽  
Vol 20 (107) ◽  
pp. 731 ◽  
Author(s):  
IR Willett ◽  
ML Higgins
Keyword(s):  
Ammonium Nitrogen ◽  
Early Growth ◽  
Mineral Nitrogen ◽  
Lowland Rice ◽  
Rice Crop ◽  
Growth Stages ◽  
Poor Growth ◽  
Nitrogen Levels ◽  
Crop Uptake ◽  
Upland Crop

Surface soil (0-150 mm) mineral nitrogen levels were monitored in field plots undergoing rice-wheat-wheat and rice-fallow rotations to study the effects of rice growing on the mineral nitrogen content of soils for subsequent crops. Ammonium nitrogen accumulated in the soils during the first 3 weeks of flooding of the rice crop, reaching 54 mg N kg-1 in a grey clay, and 23 mg N kg-1 in a transitional red-brown earth. Thereafter, ammonium nitrogen decreased so that at the time of drainage the soils contained between 2 and 6 mg N kg-1. Nitrate levels during the flooding period fluctuated between 1 and 7 mg N kg-1. In each subsequent fallowing period, nitrate levels increased so that there was approximately 20 mg N kg-1 as nitrate present during the early growth stages of the post-rice crops. However, at the harvests of each post-rice crop, nitrate nitrogen levels had decreased to between 1 and 7 mg N kg-'. Fluctuations in nitrate levels were interpreted in terms of gains from mineralization and nitrification and losses by crop uptake, although leaching and denitrification during periods of heavy rainfall or irrigations could not be assessed. Ammonium levels in the post-rice period increased in the months of October and November when fallowed, but other fluctuations showed no consistent trends. Nitrite levels were low (< 0.6 mg N kg-1) throughout the experiments. Total mineral nitrogen levels during the early growth stages of the crops grown after the rice corresponded to between 31 and 95 kg N ha-1 in the surface 0-150 mm of soil. It was concluded that in the rotations studied, lowland rice cropping did not lead to depletion of mineral nitrogen to such an extent that it could be implicated as a factor in the poor growth of upland crops grown in rotation with lowland rice.

Influence of Photochemical Reactions on the Content and Transformation of Mineral Nitrogen in Sod-Podzol Soil

2018 ◽  
Vol 781 ◽  
pp. 195-199
Author(s):  
Sergey Novoselov
Keyword(s):  
Nitrate Nitrogen ◽  
Ammonium Nitrogen ◽  
Photochemical Reactions ◽  
Mineral Nitrogen ◽  
Light Energy ◽  
Second Stage ◽  
Humus Substances ◽  
Microbiological Oxidation ◽  
Two Stages

The article discusses the photochemical effects of sunlight on the soil. Under the influence of light energy the amount of mineral and easy hydrolysable nitrogen, as well as labile humus substances increased in the soil. The photochemical destruction of humus substances was accompanied by an increase in their mobility and loss of colour. The article shows that the process of mineral nitrogen formation in the soil during the photochemical destruction of humus substances has two stages. The first stage includes photochemical reactions with the formation of ammonium nitrogen. The second stage is the microbiological oxidation of ammonium nitrogen to the nitrate nitrogen.

scholarly journals P1207ANALYSIS OF OUTCOME AND FACTORS ASSOCIATED WITH MAINTENANCE OF PERITONEAL DIALYSIS

2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Merita Rroji (Molla) ◽  
Saimir Seferi ◽  
Larisa Shehaj ◽  
Myftar Barbullushi
Keyword(s):  
Renal Function ◽  
Peritoneal Dialysis ◽  
Residual Renal Function ◽  
Good Survival ◽  
First Year ◽  
Technical Failure ◽  
Technique Survival ◽  
Ultrafiltration Failure ◽  
Comorbidity Index ◽  
Short Time

Abstract Background and Aims Peritoneal dialysis (PD) is generally associated with a good survival rate and with great preservation of residual renal function (RRF). The various causes of technique failure are responsible for the relative short time staying in PD. Objectives: This study aimed to analyze the outcome and factors correlated with maintenance peritoneal dialysis (PD) to guide for improving prognosis. Method In a retrospective way we examined our PD-cohort concerning mortality, technique survival, peritonitis rate, and other complications. Results From 2005 to 2019 the number of PD patients who have been treated in PD program for more than 3 months was around 199 patient, 29.1% diabetics, mean age 53.3±15.03 years old and meantime in therapy 32.39± 27.34 months. The PD was seen as an alternative for younger patients in the transplant list and elderly patients with comorbidity. Around 7.5% of the PD patients were transplanted and 8.5 % of patients were transferred from HD due to vascular access failure. Around 88.9% of patients were on PD for more than 1 year, 37.7% from 3 up to 5 years and 19.8% percent of the patients have stayed on PD for more than 5 years. Cardiovascular mortality was the main cause of mortality with 53% of the cases. Higher comorbidity index, lower albumin levels, and lower residual renal function were the main risk factors for lower survival. The technical survival of patients was 92.3% during the first year, 79.5% and 69.6% in the second and the fifth year, respectively. There was not found a difference in technical survival between diabetics and nondiabetics patients. Ultrafiltration failure followed by peritonitis was the main reason for transfer patients with more than 24 months in therapy in hemodialysis probably linked with the no availability of icodextrin. Peritonitis rate was 1:41 patient months. Conclusion PD program in our center is organized based in the concept of integrated care in RRT. The outcome of our patients was at least comparable to those reported by larger registries Although we have done good progress in the prevention of infection the nonavailability of icodextrin is an important factor for a technical failure. RRF is an important factor and we need to be more focused to maintain it longer in the future.

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