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P. P. King

Bio: P. P. King is an academic researcher from Society of Chemical Industry. The author has contributed to research in topics: Intensive farming. The author has an hindex of 1, co-authored 1 publications receiving 5 citations.

Papers
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Journal ArticleDOI
TL;DR: In the middle decades of this century large-scale intensive agriculture relied heavily on the availability of cheap synthetic nitrogenous fertilizers as discussed by the authors. But little attention then had to be paid to th...
Abstract: During the middle decades of this century large-scale intensive agriculture relied heavily on the availability of cheap synthetic nitrogenous fertilisers. Little attention then had to be paid to th...

5 citations


Cited by
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TL;DR: Although the recent fall in the price of oil will ultimately be reflected in some reduction in the prices of nitrogenous fertilizers, the cost of the latter will still be sufficient to maintain inter...
Abstract: Although the recent fall in the price of oil will ultimately be reflected in some reduction in the price of nitrogenous fertilizers the cost of the latter will still be sufficient to maintain inter...

28 citations

Journal ArticleDOI
TL;DR: In this paper, a simple and effective modification to the standard Kjeldahl procedure is proposed which includes nitrate-N in the total nitrogen determination in dry soil and plant material, the method involves the nitration of a phenolic compound, such as phenyl acetate, followed by subsequent recovery of the nitrogen as ammonium by standard KJldahl analysis.
Abstract: The standard Kjeldahl method does not recover nitrate‐N quantitatively. A simple and effective modification to the standard Kjeldahl procedure is proposed which includes nitrate‐N in the total nitrogen determination in dry soil and plant material, The method involves the nitration of a phenolic compound, such as phenyl acetate, followed by subsequent recovery of the nitrogen as ammonium by standard Kjeldahl analysis

20 citations

Dissertation
01 Jan 1992
TL;DR: In this article, the authors investigated how the N dynamics of a 'typical' arable soil in south-east Scotland receiving recommended fertiliser N applications were modified by: 1) reducing the amount of N application, 2) replacing the fertiliser with a leguminous source of N (forage peas grown as a green manure crop); 3) growing a winter cover crop.
Abstract: It has become evident that the benefits of increased fertiliser N use in the UK may be offset by problems, such as nitrate leaching to surface and groundwaters. The broad objectives of this work were to investigate how the N dynamics of a 'typical' arable soil in south­ east Scotland receiving recommended fertiliser N applications were modified by: 1) reducing fertiliser N application; 2) replacing the fertiliser N with a leguminous source of N (forage peas grown as a green manure crop); 3) growing a winter cover crop. All experimentation was field-based, with the main emphasis upon the direct measurement of NO3-N leaching losses from eight 300 m 2 hydrologically isolated field plots, complemented by routine measurements of crop N uptake, soil mineral N, atmospheric N deposition and N 20 flux. N 2 fixation in the leguminous green manure was also measured, plus the mineralisation of the incorporated legume material. The efficacy of hydrological plot isolation in local soil types was first investigated using a small pilot plot. The main experimental period began with incorporation of the green manure in September 1987 and ended in April 1989. Crop yields were low and the utilisation of applied N very poor. There was no apparent financial incentive to reduce fertiliser N application or replace it with a leguminous green manure. Variable drainflow recovery from the plots hampered accurate estimation of N O 3-N leaching losses, but results suggested that: leaching losses from arable soils in south-east Scotland are generally less than in southern Britain; reducing fertiliser N application had little effect upon leaching losses; autumn incorporation of the green manure increased leaching during the following winter; autumn cultivation increased leaching compared with no cultivation; spring-applied fertiliser N was susceptible to leaching loss; growth of a winter cover crop may have reduced winter leaching. Denitrification was likely to have been a very important N loss process, but was very difficult to measure directly in the heavy, poorly structured soil type. Despite very high levels of symbiotic N 2 fixation (over 300 kg N ha-1), the use of the leguminous green manure to increase available N for the following crop was limited under local soil and climatic conditions. This was due to the complex nature of legume decomposition and mineralisation and led to the poor synchronisation of legume N release and crop N uptake in the autumn and spring after incorporation. It is likely, however, that a leguminous green manure would be of value in maintaining the long-term N status of an arable soil. Experimental data was summarised in the form of N balance sheets for the different experimental treatments. These suggest that although the highest non-harvest losses occurred from the application of a recommended fertiliser N rate, this treatment retained mineral N within the arable soi1-plant system most efficiently. GLOSSARY OF ABBREVIATIONS: See page number for full definition: UNITS OF MEASUREMENT Area: m 2 square metre ha hectare Length: m metre cm centimetre mm millimetre Mass : t tonne kg kilogram g gram mg milligram Time : 5 second hr hour Volume : 1 litre

5 citations

Journal ArticleDOI
TL;DR: In this paper, the development and marketing of novel technology by the chemical industry has been a fundamental ingredient in the improvement of crop yields, and the need for substantially increased investment in basic plant research, a requirement already recognized within the Chemical industry.
Abstract: The development and marketing of novel technology by the chemical industry has been a fundamental ingredient in the improvement of crop yields. Further advances will result from the continuing development of more effective pesticides. Improved application technology and better diagnosis of precise crop requirements will also lead to the more efficient usage of existing and future products. New approaches to crop improvement based on chemical plant-growth regulators and genetic engineering of plants represent major technological opportunities for the future. Realization of these opportunities demands a substantially increased investment in basic plant research, a requirement already recognized within the chemical industry.

2 citations

01 Jan 2018
TL;DR: In this article, Nitrogen fertilizer effects on black cherry regeneration in Allegheny Hardwood Forests were studied in the area of the Allegheny Plateau in the US state of Pennsylvania.
Abstract: ....................................................................................................................................... viii Chapter 1. Literature Review .......................................................................................................... 1 Background of Study Area: Allegheny Plateau .............................................................................. 1 Geology and Climate of Allegheny Plateau ............................................................................ 1 Soils of the Allegheny Plateau ................................................................................................ 2 History of Black Cherry and Nitrogen Deposition on the Allegheny Plateau ................................ 5 History of Nitrogen Deposition ............................................................................................... 8 The Nitrogen Cycle and Deposition ............................................................................................. 11 Changes in Black Cherry Vitality and Regeneration .................................................................... 13 Atmospheric Deposition Changes ................................................................................................. 17 Chapter 2. Manuscript: Nitrogen fertilizer effects on black cherry (Prunus serotina Ehrh) regeneration in Allegheny Hardwood Forests .............................................................................. 19 Introduction ................................................................................................................................... 19 Methods......................................................................................................................................... 24 Site Establishment – Low N-Fertilized Sites ......................................................................... 24 Site Establishment –High N-Fertilized Areas ....................................................................... 25 Field Methods and Data Collection .............................................................................................. 26 Treatment – Low N-Fertilized Sites ...................................................................................... 26 Treatment – High N-Fertilized Areas ................................................................................... 26 Regeneration Measurements – Low N-Fertilized Sites ......................................................... 27 Regeneration Measurements – High N-fertilized Areas ....................................................... 27 iv Soil Measurements – Low N-Fertilized Sites ........................................................................ 27 Soil Measurements – High N-Fertilized Areas ..................................................................... 29 Overstory MeasurementsLow N-Fertilized Sites ................................................................ 29 Overstory Measurements – High N-Fertilized Areas ........................................................... 30 Experimental Design and Statistical Analyses ............................................................................. 31 Results ........................................................................................................................................... 31 Regeneration – Low N-Fertilized Sites ................................................................................. 32 Regeneration – High N-Fertilized Areas .............................................................................. 33 Soil Measurements – Low N-Fertilized Sites ........................................................................ 34 Soil Measurements – High N-Fertilized Areas ..................................................................... 35 Overstory MeasurementsLow N-Fertilized Sites ................................................................ 36 Overstory Measurements – High N-Fertilized Areas ........................................................... 37 Discussion ..................................................................................................................................... 37 Regeneration ......................................................................................................................... 37 Soil and Overstory ................................................................................................................ 40 Conclusion .................................................................................................................................... 44 References ..................................................................................................................................... 62 Appendix ....................................................................................................................................... 73 Vita ................................................................................................................................................ 86

1 citations