scholarly journals Economics of phosphorus fertiliser use on pastures 2. Incorporating the residual effect

1987 ◽  
Vol 15 (4) ◽  
pp. 445-451 ◽  
Author(s):  
G. M. Scobie ◽  
N. R. St-Pierre
Keyword(s):  
Residual Effect ◽  
Phosphorus Fertiliser ◽  
Fertiliser Use

scholarly journals Measuring On-Farm Phosphorus Fertiliser Use—Lessons Learned from Surveying Data of Five Regions in Northern Germany

Agronomy ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2123
Author(s):  
Paul Winklhofer ◽  
Sabine Andert ◽  
Silke Hüttel ◽  
Bärbel Gerowitt
Keyword(s):  
Lessons Learned ◽  
Northern Germany ◽  
Explanatory Variables ◽  
Crop Choice ◽  
Treated Area ◽  
Research Areas ◽  
Digital Database ◽  
Phosphorus Fertiliser ◽  
Fertiliser Use ◽  
On Farm

Phosphorus (P) is essential for agriculture; however, local P surpluses can have adverse environmental effects, such as eutrophication. Optimal P fertiliser use, therefore, means balancing these effects. Although P fluxes from soil to plants are key research areas, little is known about on-farm use of P fertilisers. As, typically, not all fields or crops are treated with P annually, the transferability of measurements for other nutrients, such as nitrogen, appears limited. This study aims to close this knowledge gap. On-farm P use was described using the farm records of 50 farms in five regions of northern Germany for the period of 2010 to 2018. All sources for P fertilisation were taken into account as either P mineral, P organic or P total. Two indicators for on-farm P use were suggested: frequency, which gives the percentage of the treated area, and amount, which gives the quantity used per ha of the treated area. The frequency for P total ranged from 55.9% to 93.1% of the total farm area being fertilised. Amounts between 24.8 and 41.6 kg ha−1 P total were applied on the treated area of the farm. The results supported the separation of the quantity and frequency in on-farm P use. No decrease in P use was found during the period investigated. Using mixed models, the results further show that explanatory variables, including the farm characteristics and crop choice, explain the substantial variations in P use. It is recommended for the example of Germany to establish an official digital database for P fertilisers that can be updated professionally and is mandatory for all documentation on P use.

Effect and residual effect of N fertilisation on the N uptake of winter wheat in a long-term field experiment

2002 ◽  
Vol 50 (4) ◽  
pp. 425-431 ◽  
Author(s):  
K. Berecz ◽  
I. Németh
Keyword(s):  
Winter Wheat ◽  
N Uptake ◽  
Residual Effect ◽  
Brown Forest Soil ◽  
Vegetative Organs ◽  
Set Up ◽  
Fertiliser Use ◽  
N Status ◽  
Term Field

In wheat production, N fertilisation is one of the most effective agro-technical devices to increase yield and N concentration. In Hungary, fertiliser use, particularly that of N, has dropped dramatically in the last decade. The aim of this experiment was to study the direct and residual effect of N fertilisation on the grain yield and N uptake of winter wheat after 30 years of intensive N fertilisation. A long-term fertilisation experiment was set up on brown forest soil (Eutric Cambisol) with medium N status at Keszthely (Hungary) in 1965. In 1995, the plots were halved. From that year on, half of the plots no longer received N fertiliser, while the other half of the plots was fertilised with increasing N doses. Two years after the treatment modification, no residual effect of long-term intensive N fertilisation (10.44 t N/30 years) could be detected. Under the investigated site conditions, the omission of yearly N fertilisation led to low wheat yields and low N concentrations both in the grains and in the vegetative organs above the uppermost internode.

Factors affecting the adoption of productive pastures by participants in a paired-paddock extension program

2000 ◽  
Vol 40 (8) ◽  
pp. 1089 ◽  
Author(s):  
J. P. Trompf ◽  
P. W. G. Sale ◽  
B. Graetz
Keyword(s):  
Regression Models ◽  
Management Practices ◽  
Annual Rainfall ◽  
Stocking Rate ◽  
Factors Affecting ◽  
Exit Survey ◽  
Eastern Australia ◽  
Phosphorus Fertiliser ◽  
Fertiliser Use ◽  
Extension Program

A survey of 146 pastoral producers across south-eastern Australia was conducted after they had participated for 3 years in the Grassland’s Productivity Program. The exit survey, together with earlier surveys, enabled the changes in whole-farm stocking rate and phosphorus fertiliser use, management practices, and perceptions of the Grassland’s Productivity Program, to be determined. The magnitude of the increases in productivity settings and the increased use of most recommended management practices were not influenced by either the facilitator who guided the groups of participants, or by the annual rainfall for the farm, which varied between 400 and 1000 mm. Path analysis of the survey data found that changes in productivity settings during 1993–97 did not depend on any one feature of the extension program. Rather the changes resulted from a hierarchy of interacting effects including certain initial (1993) and final (1997) management practices, attitudes to the program and perceived benefits from the program, and situational constraints such as the availability of suitable soil types on the farm. There were differences in the significant terms in the regression models that predicted the change in stocking rate, the change in fertiliser rate, or the combined variable for both, that was designated as the change index.

Concanavalin A-induced Aggregation of Human Blood Platelets

1975 ◽  
Vol 33 (02) ◽  
pp. 354-360 ◽  
Author(s):  
Heinrich Patscheke ◽  
Reinhard Brossmer
Keyword(s):  
Concanavalin A ◽  
Binding Capacity ◽  
Specific Binding ◽  
Blood Platelets ◽  
Residual Effect ◽  
Independent Effect ◽  
Con A ◽  
Experimental Conditions ◽  
Main Effect ◽  
Induced Aggregation

SummaryConcanavalin A (CON A) causes platelets to aggregate. A Ca++-independent effect of CON A could be separated from a main effect which depends on Ca++. The main effect probably is a consequence of the CON A-induced platelet release reaction and therefore is platelet-specific. The weak residual effect observed in the presence of Na2EDTA may be due to a similar mechanism as has been demonstrated for CON A-induced aggregations of several other normal and malignant transformed animal cells.Na2EDTA did not inhibit the carbohydrate-specific binding capacity of CON A. Therefore, Na2EDTA appears not to demineralize the CON A molecules under these experimental conditions.α-methyl-D-glucoside inhibits the Ca++-independent as well as the Ca++-dependent effect of CON A.Pretreatment by neuraminidase stimulated the platelet aggregation induced by CON A. It is possible that removal of terminal sialic acid residues makes additional receptors accessible for the binding of CON A.

Thigh Cuff Effects on Venous Flow Redistribution During 4 Days in Dry Immersion

2020 ◽  
Vol 91 (9) ◽  
pp. 697-702
Author(s):  
Philippe Arbeille ◽  
Danielle Greaves ◽  
Laurent Guillon ◽  
Stephane Besnard
Keyword(s):  
Left Ventricle ◽  
Ejection Fraction ◽  
Jugular Vein ◽  
Residual Effect ◽  
Cerebral Vein ◽  
Fluid Shift ◽  
Venous Flow ◽  
Additional Measure ◽  
Dry Immersion ◽  
Vein Diameter

PURPOSE: The objective was to quantify the venous redistribution during a 4-d dry immersion (DI) and evaluate the effect of thigh cuffs.METHODS: The study included nine control (Co) and nine subjects wearing thigh cuffs during the daytime (CU). Ultrasound measures were performed Pre-DI, on day 4 AM (D4 AM) and D4 PM: left ventricle stroke volume and ejection fraction (SV, EF), jugular vein volume (JVvol), portal vein diameter (PV), and middle cerebral vein velocity (MCVv). An additional measure of JVvol was performed on Day 1 after 2 h in DI.RESULTS: After 2 h in DI, JVvol increased significantly from Pre in both groups, but increased more in the Co compared to the CU subjects (Co: 0.27 0.15 cm3 to 0.94 0.22 cm3; CU: 0.32 0.13 cm3 to 0.64 0.32 cm3). At D4 AM, SV and EF decreased from Pre (SV: 111 23 cm3 to 93 24 cm3; EF: 0.66 0.07 to 0.62 0.07). JVvol was slightly increased (Co: 0.47 0.22 cm3 CU: 0.35 014 cm3). MCVv and PV remained unchanged from Pre-DI. No difference was found between the two groups for any of the parameters measured. From D4 AM to PM, no significant change was observed for any parameter.CONCLUSION: The results confirm that DI induces, during the first 2-3 h, a significant cephalic fluid shift as observed in spaceflight. During this early phase, the thigh cuffs reduced the amplitude of the fluid shift toward the head, but after 4 d in DI there was only a slight memory (residual) effect of DI on the jugular volume and no residual effect of the thigh cuffs.Arbeille P, Greaves D, Guillon L, Besnard S. Thigh cuff effects on venous flow redistribution during 4 days in dry immersion. Aerosp Med Hum Perform. 2020; 91(9):697702.

Nutrient economy through land configuration and residue management in a greengram (Phaseolus radiatus L.)-wheat (Triticum aestivum L.) cropping sequence with limited water supplies

2005 ◽  
Vol 52 (4) ◽  
pp. 369-379
Author(s):  
B. G. Shivakumar ◽  
B. N. Mishra ◽  
R. C. Gautam
Keyword(s):  
Grain Yield ◽  
Agricultural Research ◽  
Indian Agricultural Research Institute ◽  
Residual Effect ◽  
Residue Management ◽  
Phosphorus Fertilization ◽  
Significant Interaction Effect ◽  
Preceding Crop ◽  
Cropping Sequence ◽  
Phosphorus Application

A field experiment on a greengram-wheat cropping sequence was carried out under limited water supply conditions in 1997-98 and 1998-99 at the farm of the Indian Agricultural Research Institute, New Delhi. The greengram was sown either on flat beds or on broad beds 2 m in width, divided by furrows, with 0, 30 and 60 kg P2O5/ha. After the harvest of greengram pods, wheat was grown in the same plots, either with the greengram stover removed or with the stover incorporated along with 0, 40, 80 and 120 kg N/ha applied to wheat. The grain yield of greengram was higher when sown on broad beds with furrows compared to flat bed sowing, and the application of 30 or 60 kg P2O5/ha resulted in significantly higher grain yields compared to no phosphorus application. The combination of broad bed and furrows with phosphorus fertilization was found to be ideal for achieving higher productivity in greengram. The land configuration treatments had no impact on the productivity of wheat. The application of phosphorus to the preceding crop had a significant residual effect on the grain yield of wheat. The incorporation of greengram stover also significantly increased the grain yield of wheat. The increasing levels of N increased the grain yield of wheat significantly up to 80 kg/ha. The combination of greengram stover incorporation and 80 kg N/ha applied to wheat significantly increased the grain yield. Further, there was a significant interaction effect between the phosphorus applied to the preceding crop and N levels given to wheat on the grain yield of wheat.

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