Soil compaction and fertilisation effects on nutrient content and cellular fluid pH of spring barley (Hordeum vulgare L.)

E. Reintam¹, J. Kuht¹, H. Loogus², E. Nugis² and K. Trükmann¹

¹Estonian University of Life Sciences, Institute of Agricultural and Environmental Sciences, Kreutzwaldi Str. 64, 51014 Tartu, Estonia; e-mail: endla.reintam@emu.ee
²Estonian Institute of Agricultural Engineering, Teaduse 13, 75501 Saku, Harjumaa, Estonia

Abstract:

The main objective of this work was to investigate the effect of soil bulk density on nutrient (N, P, K) assimilation and on cellular fluid pH of spring barley (Hordeum vulgare L.) with different levels of fertilisation. Data were collected from the research fields of the Estonian University of Life Sciences (58^o23´N, 26^o44´E) with four different levels of soil compaction on sandy loam Stagnic Luvisol from 2001 to 2003. The soil was compacted by a tractor MTZ-82 (with loader; total weight 4.9 Mg) before spring sowing. Four levels of fertilisation (N0P0K0, N40P7K20; N80P14K40; N120P21K80) were applied using N20: P3.5: K10 fertiliser. Results of our experiments showed a high positive correlation between soil bulk density and cellular fluid pH (average r = 0.87) and negative correlation between soil bulk density and nutrient content (average r = –0.88) at highest rates of fertilisation (N80P14K40; N120P21K80) and positive correlation (r = 0.84) at lower rates of fertilisation (N0P0K0, N40P7K20) in the earing phase of barley. If the soil bulk density increased up to the level 1.56 Mg m^-3, there was a sudden increase of cellular fluid pH without fertiliser use. Use of fertilisers decreased the barley stress. A sudden increase of cellular fluid pH started after soil bulk density 1.61 Mg m^-3. The greatest impact of soil compaction was on nitrogen and potassium content in barley dry matter in all fertilisation levels. The nitrogen and potassium content in barley dry matter decreased up to 37% by high soil bulk density depending on fertilisation. The experiment showed that the higher decrease of nutrient content and the sudden increase of cellular fluid pH started at the same soil bulk density value.

Key words:

bulk density, cellular fluid pH, fertilisation, nutrients (N; P; K), soil compaction, spring barley (Hordeum vulgare L.)

Changes of nitrogen assimilation and intracellular fluid pH in plants of barley depending on bulk density of compacted soils

J. Kuht¹, E. Reintam², H. Loogus³ and E. Nugis³

¹Institute of Field Crop Husbandry, Estonian Agricultural University
²Institute of Soil Science and Agrochemistry, Estonian Agricultural University
³Estonian Research Institute of Agriculture

Abstract:

The penetration resistance of different arable soils is quite different depending on the Estonian area. We are briefly introducing the results of our research on soil compaction, penetration resistance of different soils in Estonia, uptake of nutrients and changes of intracellular fluid pH of barley depending on soil bulk densities. These data were mainly collected in a research field (58º23´N, 26º44´E) of the Estonian Agricultural University, with different levels of soil compaction (10 levels) on sandy loam Fragi-Stagnic Albeluvisol (WRB) soil in 2001 and 2002. The investigated cultural plant was spring barley (Hordeum vulgare L.). In Estonia H. Loogus has studied changes of cellular fluid pH, depending on seedbed, by using microelectrodes directly on plants by quick method. The effect of soil bulk density on cellular fluid pH of barley leaves generally depends of number of passes. The experiment showed also that a higher decrease in nitrogen content started at the same soil bulk density value as the cellular fluid pH quickly increased. If the soil bulk density was increasing up to level 1.52–1.54 Mg m^-3, the cellular fluid pH suddenly increased very quickly. Nitrogen assimilation change in plants of barley decreased at the same bulk density values as a remarkable increase of intracellular pH was observed.

Key words: