Agricultural systems engineering (greenhouse, fish farming, mushroom production)
M. ALmoosa; S. Al-Atab; S. Almaliki
Abstract
Soil properties play a fundamental role in the success of agricultural operations through their impact on crop growth and quality, as they determine their ability to retain water and absorb nutrients, and affect soil aeration and the root system. The aim of this study is to predict bulk density and resistance ...
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Soil properties play a fundamental role in the success of agricultural operations through their impact on crop growth and quality, as they determine their ability to retain water and absorb nutrients, and affect soil aeration and the root system. The aim of this study is to predict bulk density and resistance to soil penetration under different moisture levels during tillage operations. It includes four moisture levels: 7, 14, 22, and 28%, and three types of plows: the moldboard plow, chisel plow, and disc plow. Moreover, soil samples were collected at two depths: 15 cm and 30 cm. The change in the physical properties of the studied soil is also measured during the growth periods of wheat crop (after tillage, beginning of the season and end of the season). The study is conducted in Al-Qurna district, north of Basra Governorate, Iraq, in clay loam soil. The results are analyzed and mathematical equations are obtained to predict the studied properties using the response surface methodology. The obtained results indicate that soil moisture during plowing, plow type, soil depth, and crop growth periods have a significant effect on soil bulk density and penetration resistance. The 14% moisture treatment is superior, recording the lowest bulk density and lowest penetration resistance of 1.12 Mg m-3 and 1133 kN m-2, respectively. While the 28% moisture treatment provided the highest bulk density and highest penetration resistance of 1.22 Mg m-3 and 1379 kN m-2, respectively. The results also show that increasing the soil depth from 15 to 30 cm increases the bulk density and soil penetration resistance, by 12 and 45.70%, respectively. Plowing with a disc plow improves soil properties, giving the lowest bulk density and penetration resistance of 1.12 Mg m-3 and 1074 kN m-2, respectively. While using the chisel plow leads to recording the highest bulk density and penetration resistance, which reached 1.22 Mg m-3 and 1442 kN m-2, respectively. As for the moldboard plow, the bulk density and soil penetration resistance reached 1.18 Mg m-3 and 1282 kN m-2, respectively. The growth periods have a significant effect on the studied soil properties where the beginning of the growing season provided the lowest bulk density. The bulk density reached 1.17, 1.13, and 1.23 Mg m-3 for the periods after plowing, at the beginning of the season and its end, respectively. While the penetration resistance after plowing is superior with the lowest resistance compared to the beginning of the season and its end, as it reached 897, 1327, and 1573 kN m-2, respectively. The results of data analysis show that the obtained mathematical models accurately and efficiently predict bulk density and soil resistance to penetration under the experimental conditions, with a high coefficient of determination (R2) of 0.6460 and 0.8114 for the bulk density and penetration resistance, respectively.
A. Heidari; A. Ghadami Firouzabadi
Abstract
Introduction: Conventional tillage is widely used in sugar beet growing areas. However, conventional farming uses more labour and machines that has a negative effect on soil and the environment. Due to limited water resources and recent droughts, proper use of modern tillage and irrigation methods can ...
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Introduction: Conventional tillage is widely used in sugar beet growing areas. However, conventional farming uses more labour and machines that has a negative effect on soil and the environment. Due to limited water resources and recent droughts, proper use of modern tillage and irrigation methods can increase water efficiency and prevent soil degradation as a result of sustainable agriculture.Materials and Methods: An experiment was conducted to investigate different methods of tillage and water requirements on quantitative and qualitative yield and sugar beet water productivity in the drip irrigation system in Ekbatan Research Station of Hamedan Province from 2018 to 2019. A strip plot experiment with sixteen treatments and three replications was used. Tillage methods in four levels, consisting of T1- plowing with moldboard plow to a depth of 25-30 cm in autumn + power harrow to a depth of 15-20 cm in spring, T2- subsoiling to a depth of 35-40 cm + plowing with moldboard plow to a depth of 25-30 cm in autumn + power harrow to a depth of 15-20 cm in spring, T3- plowing with chisel plow equipped with roller packer to a depth of 25-30 cm in autumn + power harrow to a depth of 15-20 cm in spring and T4- plowing with sweep plow equipped with roller packer to a depth of 25-30 cm in autumn + power harrow to a depth of 15-20 cm in spring and Irrigation factor consisting of I1-100%, I2- 90%, I3- 80% and I4- 70% sugar beet water requirement were considered. Soil penetration resistance (PR), the volume of water consumption, root yield, sugar yield, white sugar yield and molasses were measured. Water efficiency in tillage and irrigation treatments was also calculated. MSTAT-C software was used for statistical analysis of data. The Duncan's multiple range test at a 1% probability level was used to compare the means.Result and Discussion: At a depth of 0-30 cm, no significant difference was observed between tillage methods on soil penetration resistance. At greater depths (35-40 cm) T2 treatment (subsoil + moldboard plow) had the greatest effect in reducing soil resistance. The results showed that the effect of different tillage methods, water requirement and their interactions at the 1% probability level on root yield; sugar yield and white sugar yield were significant. There was no significant difference between sugar beet yield in the T4 tillage treatment and the conventional method (T1). Treatments T4 (with an average yield of 50686 kg ha-1) and T1 (with an average yield of 50507 kg ha-1) had the highest sugar beet root yield. Also, the tillage method (T4) compared to the conventional tillage method (T1) reduced fuel consumption by 14.7% and increased field capacity by 52.4% respectively. In the T4 tillage method, irrigation treatments I100, I90 and I80 with mean water productivity of 6.113, 6.087 and 5.523 kg m-3 of water consumption, respectively, had the greatest effect on increasing water productivity, while no significant difference was observed between them.Conclusion: The tillage method (T4) compared to the conventional tillage method (T1) reduced fuel consumption by 14.7% and increased field capacity by 52.4%, respectively. There was no significant difference between sugar beet yield and water productivity in the T4 tillage treatment and the conventional method (T1). Although full irrigation treatment (100% water requirement) has the highest water efficiency, there is no significant difference between 90 and 80% water requirement treatment. Therefore, in order to save water consumption, 80% water requirement is recommended. The result is that in the T4 tillage method with a supply of 80% water requirement of sugar beet after plant establishment (approximately from the middle of the growing season) about 12% (1207 m-3) in water consumption without significant reduction in water productivity.
