Interrill Erodibility Affected by Cropping Systems and Initial Soil Water Content

Soil water conservation through tillage is one of the appropriate ways of addressing soil moisture deficit in rainfed agriculture. This study evaluated the effects of tillage practices on soil moisture conservation and crop yields in Mwala District, Eastern Kenya during the long rains (LR) and short rains (SR) of 2012/13. Six tillage systems: Disc plough (MB), Disc plough and harrowing (MBH), Ox-ploughing (OX), Subsoiling – ripping (SR), Hand hoe and Tied Ridges (HTR) and Hand hoe only (H) and, three cropping systems namely, sole maize, sole bean and maize - bean intercrop, were investigated in a split-plot design with four replicates. Data on soil water content was monitored at different weeks after planting and the crop yields at end of each growing season. A three-season average shows that soil water content and crop yields were higher in conventional tillage methods compared to the conservation tillage methods. Long term tillage experiments are thus required at different locations, under various environmental and soil conditions to validate the study findings.

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Preferential flow of surface‐applied solutes: Effect of lysimeter design and initial soil water content

Vadose Zone Journal ◽

10.1002/vzj2.20052 ◽

2020 ◽

Vol 19 (1) ◽

Author(s):

Mark R. Williams ◽

Oscar Coronel ◽

Scott J. McAfee ◽

Laura L. Sanders

Keyword(s):

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Preferential Flow ◽

Initial Soil

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Numerical Modeling of Water Movement from Buried Vertical Ceramic Pipes through Soils

Journal of Engineering ◽

10.31026/j.eng.2018.06.06 ◽

2018 ◽

Vol 24 (6) ◽

pp. 72

Author(s):

Zena Kamil Rasheed ◽

Maysoon Basheer Abid

Keyword(s):

Hydraulic Conductivity ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Transient Flow ◽

Initial Conditions ◽

Irrigation System ◽

Pipe Length ◽

Ceramic Pipe ◽

Initial Soil

The problem of water scarcity is becoming common in many parts of the world, to overcome part of this problem proper management of water and an efficient irrigation system are needed. Irrigation with a buried vertical ceramic pipe is known as a very effective in the management of irrigation water. The two- dimensional transient flow of water from a buried vertical ceramic pipe through homogenous porous media is simulated numerically using the HYDRUS/2D software. Different values of pipe lengths and hydraulic conductivity were selected. In addition, different values of initial volumetric soil water content were assumed in this simulation as initial conditions. Different values of the applied head were assumed in this simulation as boundary conditions. The results of this research showed that greater spreading occurs in the horizontal direction. Increasing applied heads, initial soil water contents and pipe hydraulic conductivities, cause increasing the size of wetting patterns but in a few increases. Also, the results showed that the empirical formulas which can be used for expressing the wetted width and depth in terms of applied head, initial soil water content, application time, pipe hydraulic conductivity, and pipe length, are good and can be used as design equations.

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Numerical Modeling of Water Movement from Buried Vertical Ceramic Pipes through Coarse Soils

Al-Khwarizmi Engineering Journal ◽

10.22153/kej.2017.06.003 ◽

2018 ◽

Vol 13 (4) ◽

pp. 164-173

Author(s):

Zena Kamil Rasheed ◽

Maysoon Basheer Abid

Keyword(s):

Hydraulic Conductivity ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Transient Flow ◽

Vertical Direction ◽

Empirical Formulas ◽

Pipe Length ◽

Ceramic Pipe ◽

Initial Soil

Problem of water scarcity is becoming common in many parts of the world. Thus to overcome this problem proper management of water and an efficient irrigation systems are needed. Irrigation with buried vertical ceramic pipe is known as a very effective in management of irrigation water. The two- dimensional transient flow of water from a buried vertical ceramic pipe through homogenous porous media is simulated numerically using the software HYDRUS/2D to predict empirical formulas that describe the predicted results accurately. Different values of pipe lengths and hydraulic conductivity were selected. In addition, different values of initial volumetric soil water content were assumed in this simulation as initial conditions. Different values of applied head were assumed in this simulation as a boundary conditions. In general, a good agreement was obtained when comparing the predicted results with available measured values. The results of this research showed that greater spreading occur in vertical direction. Increasing applied heads, initial soil water contents, pipe hydraulic conductivities, cause increasing the size of wetting patterns. Also the results showed that the empirical formulas which can be used for expressing the wetted width and depth in terms of applied head, initial soil water content, application time, pipe hydraulic conductivity, and pipe length, are good and can be used as a designing equations.

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The Structure and Diversity of Nitrogen Functional Groups from Different Cropping Systems in Yellow River Delta

Microorganisms ◽

10.3390/microorganisms8030424 ◽

2020 ◽

Vol 8 (3) ◽

pp. 424 ◽

Cited By ~ 3

Author(s):

Huan He ◽

Yongjun Miao ◽

Lvqing Zhang ◽

Yu Chen ◽

Yandong Gan ◽

...

Keyword(s):

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Yellow River ◽

Cropping Systems ◽

Yellow River Delta ◽

N Cycling ◽

River Delta ◽

Ammonia Oxidizer ◽

Rotation System

The Yellow River Delta (YRD) region is an important production base in Shandong Province. It encompasses an array of diversified crop systems, including the corn–wheat rotation system (Wheat–Corn), soybean–corn rotation system (Soybean–Corn), fruits or vegetables system (Fruit), cotton system (Cotton) and rice system (Rice). In this study, the communities of ammonia oxidizer–, denitrifier– and nitrogen (N)–fixing bacteria in those cropping systems were investigated by Illumina Miseq sequencing. We found that Rice soil exhibited significantly higher diversity indices of investigated N–cycling microbial communities than other crop soils, possibly due to its high soil water content. Wheat–Corn soils had higher abundances of nitrification gene amoA and denitrification genes nirK and nirS, and exhibited higher soil potential nitrification rate (PNR), compared with Soybean–Corn, Cotton and Fruit soils. Consistently, redundancy analysis (RDA) showed that soil water content (SWC), electrical conductivity (EC), and total nitrogen (TN) were the most important influencing factors of the diversity and structure of the investigated N–cycling microbial.

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