with the collaboration of Iranian Society of Mechanical Engineers (ISME)

Document Type : Research Article

Authors

1 Depatment of Biosystem Engineering, Faculty of Agriculture, Urmia University, Iran

2 Depatment of Soil Science, Faculty of Agriculture, Urmia University, Iran

Abstract

Introduction: Monitoring and management of soil quality is crucial for sustaining soil function in ecosystem. Tillage is one of the management operations that drastically affect soil physical quality. Conservation tillage methods are one of the efficient solutions in agriculture to reduce the soil erosion, air pollution, energy consumption, and the costs, if there is a proper management on the crop residues. One of the serious problems in agriculture is soil erosion which is rapidly increased in the recent decades as the intensity of tillage increases. This phenomenon occurs more in sloping lands or in the fields which are lacking from crop residues and organic materials. The conservation tillage has an important role in minimizing soil erosion and developing the quality of soil. Hence, it has attracted the attention of more researchers and farmers in the recent years.
Materials and Methods: In this study, the effect of different tillage methods has been investigated on the crop residues, mechanical resistance of soil, and the stability of aggregates. This research was performed on the agricultural fields of Urmia University, located in Nazloo zone in 2012. Wheat and barley were planted in these fields, consecutively. The soil texture of these fields was loamy clay and the factorial experiments were done in a completely randomized block design. In this study, effect of three tillage systems including tillage with moldboard (conventional tillage), tillage with disk plow (reduced tillage), chisel plow (minimum tillage) and control treatment on some soil physical properties was investigated. Depth is second factor that was investigated in three levels including 0-60, 60-140, and 140-200 mm. Moreover, the effect of different percentages of crop residues on the rolling resistance of non-driving wheels was studied in a soil bin.
The contents of crop residues have been measured by using the linear transects and image processing methods. In the linear transects method, the experiments were replicated three times in each block due to increasing the accuracy and mean of datawas calculated. The tests were randomly performed in each block. Then, the number of nodes, which are located on crop residues of size 25 mm, longitudinally, was counted. So the percentage of crop residue in each block was calculated through the percentage of nodes. The experiments of rolling resistance were also performed in three levels, 10, 50, and 90% of crop residues, inside the soil bin.
Results and Discussion: Result showed that, in comparison with control treatment, tillage operation significantly decreased bulk density (p<0.01), penetration resistance (p<0.01), and aggregates stability (p<0.01), in the soil surface (0-10 cm). Also, the results showed that penetration resistance of soil was increased by depth.
The results of variance analysis in crop residue dataset showed that there were significant differences among the treatments in the terms of crop residues (P<0.05). Because of increasing the intensity of tillage and also the different performance of various tillage tools would mix crop residues with the soil and lead to reduce the crop residues. The consequences revealed that the treatments had significant differences in the terms of mechanical resistance of soil at the confidence level of 5%. The mechanical resistance of soil in three levels of depth had the most and the least contents in chisel and disk plows treatments, respectively. Because of disk plows can powder soil more than other treatments and chisel plows can only make narrow in the soil. The results of investigating the effect of crop residues on rolling resistance of wheels showed that there were not any significant differences between the treatments.
Conclusions: It can be concluded that increasing the tillage intensity would reduce the stability of aggregates. Thus, the least stability of aggregates was obtained when using moldboard plows. However, the most stability was achieved using chisel and disk plows. Finally, disk plough is recommended as an appropriate tool in this research due to the high percentage of crop residues, lower mechanical resistance, lower bulk density, and higher stability of aggregates in the soil. Generally, in short-term period, conservation tillage (reduced tillage and minimum tillage) results the improvement of soil physical quality in comparison with tillage operation. Further studies on long-term effects of various tillage systems are suggested in order to select and implement of optimum tillage method in the region.

Keywords

1. Afzalinia, S., and J. Zabihi. 2014. Soil compaction variation during corn growing season under conservation tillage. Soil & Tillage Research 137: 1-6.
2. Asoudar, M. A., and H. Sabzezar. 2008. Conservation tillage systems. Publication of agricultural education. Karaj. (In Farsi).
3. Azim zadeh, S., A. Kuchaki, and M. Pala. 2002. Study on the effect of plow different methods on bulk density, porosity, soil moisture and wheat yield. Iranian Journal of Crop Scince 4: 218-233.
4. Busscher, W. J., J. R. Frederick, and P. J. Baure. 2000. Timing effects of deep tillage on penetration resistance and wheat and soybean yield. Soil Scince Socity Journal 64: 999-1003.
5. Gantzer, C. J., and G. R. Blacke. 1978. Physical characteristics of le sueur clay loam soil following no-till and conventional tillage. Agronomy Journal 70: 853-857.
6. Griffith, D. R., J. V. Mannering, and W. C. Moldehauer. 1977. Conservation tillage in the eastern corn. Journal of Soil Conservation 32: 20-28.
7. Hajabbasi, M. A., and A. Hemmat. 2000. Tillage impacts on aggregate stability and crop productivity in a clay- loam soil in central Iran. Soil & Tillage Research 56 (3, 4): 205-212.
8. Hajabbasi, M. A., A. Basalatpour, and A. R. Maleki. 2007. Effect of shifting rangeland to farmland on some physical and chemical properties of south and southwest soils of Isfahan. Journal of Scince Technology of Agriculture Natural Resource 11 (42): 525-534.
9. Lampurlane´s, J., and C. Cantero-Martınez. 2006. Hydraulic conductivity, residue cover and soil surface roughness under different tillage systems in semiarid conditions. Soil & Tillage Research 85: 13-26.
10. Rabi, G., R. G. Rasaily, H. Li, J. He, Q. Wang, and L. U. Caiyun. 2011. Influence of no tillage controlled traffic system on soil physical properties in double cropping area of North China plain. African Journal of Biotecnology 11 (4): 856-864.
11. Rousta, M. J. 2009. Effect of tillage practices on organic matter content and aggregate stability. Soil and Water Research 23: 61-67. (In Farsi).
12. Sparrow, S. D., C. E. Lewis, and C. W. Knight. 2006. Soil quality response to tillage and crop residue removal under subarctic conditions. Soil & Tillage Research 91: 15-21.
13. Taghavifar, H., and A. Mardani. 2013. Investigating the effect of velocity, inflation pressure, and vertical load on rolling resistance of a radial ply tire. Journal of Terramechanics 50: 99-106.
14. Tolon-Becerra, A., M. Tourn, G. F. Botta, and X. Lastra-Bravo. 2011. Effects of different tillage regimes on soil compaction, maize (Zea mays L.) seedling emergence and yields in the eastern Argentinean Pampas region. Soil & Tillage Research 117: 184-190.
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