Research in Agricultural Engineering, 2007 (vol. 53), issue 1
Laser profilometer testing by laboratory measurements
P. Šařec, O. Šařec, V. Prošek, K. Čížková
Res. Agr. Eng., 2007, 53(1):1-7 | DOI: 10.17221/2134-RAE 
Measuring soil surface profile has many purposes in the field of agriculture and landscape management. For example, it concerns quantitative evaluation of work quality of soil cultivation implements, and related assessment of soil surface status prior sowing. For this purpose, a prototype of laser profilometer was produced whose key parts are a laser sensor Banner LT3 fixed together with a control section, a converter etc. on a carriage that travels propelled by an electromotor along an aluminum girder. In 20 mm intervals determined by an optical sensor, the laser sensor measures a distance to a soil surface. The aim of the work is to verify some laser...
Farmland protection by means of tyre load rating
P. Prikner, A. Grečenko
Res. Agr. Eng., 2007, 53(1):8-13 | DOI: 10.17221/2131-RAE
At present, the professionals in the industry and farming still miss comparative technical data indicating the potential of agricultural vehicles and mobile machinery to inflict compaction damage upon the cultivated soil. Harmful compaction means especially the increase of soil bulk density above a critical level required for efficient plant production. In general, it seems reasonable to restrict the excessive soil compaction by loaded wheels starting from the design of farm power and machinery, which means to provide technical data on the compaction potential of tyres. This paper presents the technique of tyre rating by means of the index Compaction...
Static and kinetic friction of rapeseed
R. Rusinek, M. Molenda
Res. Agr. Eng., 2007, 53(1):14-19 | DOI: 10.17221/2129-RAE
he present paper examines the static and kinetic coefficient of friction of rapeseed. The project utilized two methods of determination of coefficient of friction of rapeseed: according Eurocode 1 (kinetic) in direct shear test and (static) in model silo. Samples of rapeseed in a range of moisture content from 6 to 15% w.b. were used and the tests were performed for galvanized steel, stainless steel and concrete B 30. Coefficient of friction for both steel types approached stable value for all levels of moisture content w.b. in a range from 0.11 to 0.18, for concrete B 30 it was found in a range from 0.25 to 0.43. The coefficient of static friction...
Redox potential, nitrate content and pH in flooded Eutric Cambisol during nitrate reduction
T. Włodarczyk, P. Szarlip, M. Brzezińska, U. Kotowska
Res. Agr. Eng., 2007, 53(1):20-28 | DOI: 10.17221/2132-RAE
Topsoils from 16 arable Cambisols developed from sand, loam and silt were used to study soil ability to nitrate reduction under flooding conditions. The strongest drop of redox potential (Eh) was observed during the first day of soil flooding. Decreasing tendency in pH values was observed of alkaline and neutral soils, and an increase in pH of acid and strongly acid soils, accompanied by a fall in Eh values. Redox potential was negatively correlated with the pH values (R2 = 0.3041; p < 0.001). The fall of NO3- varied from 20 to 100% depending on the type of soil and on the time of incubation. With a decrease...
Use of ion-selective electrodes for determination of content of potassium in Egner-Rhiem soil extracts
J. Cieśla, M. Ryżak, A. Bieganowski, P. Tkaczyk, R.T. Walczak
Res. Agr. Eng., 2007, 53(1):29-33 | DOI: 10.17221/2130-RAE
Potassium is one of the most important nutrients for plants and its content in the soil should be monitored. In the precision agriculture, which is recommended now, the ion selective electrodes are tested to determine chemical properties of the soil. The objective of this work was an evaluation of use of the valinomycin-based ion selective sensors for determination of assimilated potassium in Egner-Rhiem soil extracts. Flame photometry was used as a reference method. Results obtained from potentiometric and photometric methods in soil extracts correlated linearly (R2 = 0.84). Analysis of soil extracts by the ion selective electrodes...
Application of laser diffraction method for determination
M. Ryżak, A. Bieganowski, R.T. Walczak
Res. Agr. Eng., 2007, 53(1):34-38 | DOI: 10.17221/2133-RAE
Particle size distribution affects many physical soil properties and processes taking place in soil. There are many methods to determine the particle size distribution. The most frequently used are the sieve, sieve-pipette and sedimentation methods. Technological progress in electronics permitted a wide use of new methods of particle size distribution measurement in soil, e.g. the laser diffraction method. A comparison of particle size distribution obtained with the universally used areometer method (Cassagrande, modified by Prószynski) with results from the laser diffraction method for soil material received from grey-brown podzolic soil is presented...