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Soil compaction connected with tractor traffic leads to changes in roots morphology and decreased plant yields of both annual and perennial forage plants. The aim of this study was to quantify the effect of soil compaction on alfalfa herbage production and root growth. A pot experiment with different levels of soil compaction was conducted in 2007-09. Plant yield and root morphology such as root length density (RLD), mean root diameter (MD), specific root length (SRL), and root dry matter (RDM) were determined. Root dry matter distribution in uncompacted soil was uniform in the investigated soil layers. In compacted soil the main root matter was located in the upper soil layer. Generally, roots were also much longer in the upper soil layer (0-10 cm) than below 10 cm. The value of RLD decreased in treatments with a higher degree of compaction. It was observed that roots in more compacted soil were thinner than in uncompacted. Based on the results in herbage production, the reaction of plant yield to soil compaction can be described as positive. In the first year of the experiment (2007), soil compaction caused a significant decrease in plant yield. However, in 2008 and 2009 the opposite effect was noticed when yields were significantly higher in strongly compacted soil than in less compacted.
The field experiment was carried out on a smoothstalked meadow-grass to analyse the effect of tractor traffic on herbage production and root morphology. The multiple passes of tractor changed physical properties of soil. Increase in bulk density and penetration resistance of soil under smooth-stalked meadowgrass was recorded up to the depth of 30 cm. The tractor traffic resulted in changes in smooth-stalked meadow-grass yields. During the second and the third harvest it was found that wheel traffic decreased plant yields. For the first harvest the opposite effect in herbage production was noticed. The tractor traffic significantly changed the root morphometric properties in the upper, 0-5 cm, soil layer. Intensive tractor traffic (four and six passes) significantly increased the root length in diameter range of 0.1-0.5 mm. There were no differences in both mean root diameter and specific root length what indicated that traffic treatment applied did not change the root diameter. The results indicate that smooth-stalked meadow-grass could be recommended for compacted soils when intensive traffic is present.
The aim of this study is to analyse the influence of organic and mineral fertilization on water retention properties of soil under permanent grassland. The studies were carried out on the basis of a field experiment set out in 1997-2002 in Brzesko on silty soil. The experimental factor was mineral fertilization of NPK and manure with two doses 12.5 t ha⁻¹ and 25 t ha⁻¹ in comparison with no-fertilized, control object. Samples of soil were collected in autumn 2002 and water retention was determined using Richard's chambers method. Full dosage fertilization with 25 t ha⁻¹ of manure reduced water retention in soil about 15% relatively to not fertilized soil. Mineral ferilization (NPK) and lowered dosage of manure e.g. 12.5 t ha⁻¹ did not affected significantly water retention. After six years mineral or organic fertilizing both productive and available water retention were unchanged.
Tractor traffic as a cause of soil compaction is widely recognized as one of the most important factors responsible for environmental degradation and plant yield losses. It is a serious problem for perennial crops, where the soil surface is wheeled without any opening operation. The aim of our study was to evaluate the effect of tractor traffic on meadow fescue (Festuca pratensis) yields and root development. The field experiment was located in Mydlniki near Kraków, Poland, on silty loam Mollic Fluvisol. Experimental plots were established in randomized block design with four replications. Four compaction treatments were applied using the following range of number of passes: (P0) untreated control, (P2) two passes, (P4) four passes and (P6) six passes completely covering plot surfaces after each harvest. The dry matter (DM) of the yield and roots (RMD) were determined. Morphometric parameters of roots were estimated using image analysis software. Root length density (RLD), specific root length (SRL), and mean diameter (MD) were calculated. Tractor traffic resulted in significant influence on meadow fescue annual yields. The highest annual yields were obtained at the P2 and P4 treatments. However, in the first cut it was noticed that an increase in the number of passes increased plant yields. During the second and the third cut it was found that intensive tractor traffic decreased plant yields, probably as an effect of damage caused to above-ground parts of plants. The meadow fescue roots were significantly affected by tractor traffic only in the 5-15 cm soil layer. Tractor traffic increased the RLD value in a root diameter range of 0.1-0.5 mm. However, any other morphometric parameters, like mean root diameter (MD), specific root length (SRL) or dry root diameter (RDM) were not affected by soil compaction.
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The pH value of the soil upper horizons from 1600 profiles situated on the various altitudes above sea level has been determined. The statistically significant differences between the medium pH values of the soils of the specified biotopes from the respective climatic belts have been ascertained only in the case of: rendzinas, brown soils and pseudogley soils. Unlike the soils derived from the alkali - weathering rocks, the soils derived from the crystalline rocks do not demonstrate the significant differentiation in consideration of the acidity in relation to the altitude above sea level.
The paper presents three years (1996-98) results of an investigation into the influence of tractor wheeling on the root development of Lolium perenne. The experiment was established as randomised block design with four replicates of five wheeling treatments. During the growing season of 1996 and 1997 the swards were pressed of the wheels of the tractor URSUS C-360 (weight 2056 kg) in an identical way. The passes were always made after cuts. The combination of the passes was follows: 0, 1, 2, 4 and 6 passes on the plots of 7 m². After 3rd cut in 1998 roots were taken for investigation. Changes in soi physical properties were observed. Penetrometer resistance increase in upper 30 cm soil layer according to number of passes. This mean that soil conditions for root development changed. Roots of investigated species grow better in lightly compacted soil. Results showed that tractor wheeling reduced yielding of Lolium perenne up to 27% in proportion with number of passes. These changes in plant yielding are result of changes in soil environment and damages to plants above ground level.
Aura
|
1998
|
nr 10
18-19
The Polish Tatra Mts. occupy some 220 square kilometres, which amount to 10% of all Polish mountain areas. The beauty of these mountains attracts huge number of tourists. On average, some 10,000 people visit the Tatra Mts daily. And in peak season, this figure reaches 45,000. This has an enormous environmental impact. The authors present results of measurements along the Polana Małej Łąki tourist route carried out during one summer using an apparatus for measuring soil compactness.
The application of organic wastes, particularly composted municipal refuse and sewage sludge, significantly influenced soil structure and related physical properties of soil. A field experiment was conducted in 2005 on Stagnic Gleysol soil where different organic amendments were applied, such as compost, pig manure and sewage sludges. The results were compared with mineral fertilizers and untreated control. The amounts of all fertilizers were determined to supply 110 kg N ha⁻¹. The application of organic amendment, such as pig manure and sewage sludge, decreased the macroporosity of soil. These changes concerned the regular and irregular pores ranging 50-1000 μm in diameter. It was probably the result of a choking effect of particles leached from the sewage sludge and pig manure. Mineral fertilization, compost or sewage sludge did not influence the porosity of soil.
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