Effect of Tillage Systems on the Growth and Productivity of Eight Wheat Cultivars

A field experiment was carried out in one of the agricultural fields in Abu Ghraib region during the winter season of 2018-2019 in order to study the effect of plowing systems on the growth and productivity of eight cultivars of wheat crop in a silty clay loam, field land which was not sown in the previous season. Two tillage systems were used (no-tillage and tillage) to grow the wheat crop, moldboard plows and harrow (local made). The cultivars were (Wafia, Adena, Araz, Erratum, Pura, Spelta, Doru, and Cymto). Randomized complete blocks design (RCBD) was used in a split plot arrangement with three replications. Results revealed that Adena predominated in plant height (87.77 cm), spike length (10.68 cm) tillers (4.695 tiller plant-1), whereas Cymto was superior in plant dry weight (80.00 g), thousand grains weight (54.80 g), grains yield per unit (5.535 Kg). Genetic material of Azar, Adena and Cymto cultivars was the best, as it was clearly manifested in the phenotypic components of wheat.

Simplified Relation Model of Soil Saturation Permeability Coefficient and Air-Entry Value and Its Application

Based on the Tao and Kong (TK) model and the fractal model of the soil–water characteristic curve, a simplified model of the relationship between the saturated permeability coefficient and the air-entry value is established in this study: ks = k0ψa−2. It is shown that the saturated permeability coefficient of soil is determined by its maximum pore size. In order to facilitate the mutual prediction of saturation permeability coefficient and air-entry value, based on the data of five types of soil in the UNSODA database, the comprehensive proportionality constant k0 of the five types of soil were obtained: sand k0 = 0.03051; clay k0 = 0.001878; loam k0 = 0.001426; sandy loam k0 = 0.009301; and silty clay loam k0 = 0.0007055. Based on the obtained comprehensive proportionality constant k0 and the relationship model between saturated permeability coefficient and air intake value, the air-entry value of five kinds of soils in the existing literature and the SoilVision database were calculated. Comparing the calculated air-entry value with the measured one, the results showed that the model simplifies the traditional air-entry value prediction method to some extent and can effectively predict the air-entry value of different types of soil. On the whole, the model better predicts the air-entry value for sandy, clay, and silty clay loam than loam and sandy loam.

TERENGGANU SOIL SERIES TEXTURAL CLASSIFICATION AND ITS IMPLICATION ON WATER CONSERVATION

The updated Terengganu soil series has been made known to the public in 2018 by the Department of Agriculture, Malaysia. One of the most important physical aspects not quantify is the parameter relating to soil’s ability to contain water and allow water infiltration. This information is necessary to help farmers to know the soil suitability characteristics. In the current study, we retrieve the soil particle size of the soil series for further investigation. A pedotransfer function was used to estimate the soil water retention. The properties were then used to estimate the field capacity (FC), permanent wilting point (PWP), and the plant available water (PAW). In this study, we found twelve soil series in Terengganu state. The soil series were categorized into clay, sand, loamy sand, silty clay loam, and clay loam. Batu Hitam, Tasik, Lubok Kiat, Kampong Pusu, Tok Yong, Jerangau, and Tersat Series were found as clay soil. Jambu and Rhu Tapai Series as sand soil. Rudua, Gondang, and Kuala Brang Series corresponded to clay loam, silty clay loam, and loamy sand. Among the soil series, Gondang Series appeared to be the most preferred soil for plantation due to its ability to give the highest plant available water, a lower water infiltration duration than clay, and it required lesser water for irrigation than the clay soil.

Development and Validation of a Model for Soil Wetting Geometry Under Moistube Irrigation

We developed an empirical soil wetting geometry model for silty clay loam and coarse sand soils under a semi-permeable porous wall line source Moistube Irrigation (MTI) lateral irrigation. The model was developed to simulate vertical and lateral soil water movement using the Buckingham pi (π) theorem. This study was premised on a hypothesis that soil hydraulic properties influence soil water movement under MTI. Two independent, but similar experiments, were conducted to calibrate and validate the model using MTI lateral placed at a depth of 0.2 m below the soil surface in a soil bin with a continuous water supply (150 kPa). Soil water content was measured every 5 minutes for 100 h using MPS-2 sensors. Model calibration showed that soil texture influenced water movement (\(p\) < 0.05) and showed a good fit for wetted widths and depths for both soils ( \(nRMSE\) = 0.5% − 10%; \(NSE \ge\) 0.50; and d-index \(\ge\) 0.50. The percentage bias \(\left(PBIAS\right)\) statistic revealed that the models’ under-estimated wetted depth after 24 h by 21.9% and 3.9% for silty clay loam and sandy soil respectively. Sensitivity analysis revealed an agreeable models’ performance values. This implies the applicability of the model for estimating wetted distances for an MTI lateral placed at 0.2 m. However, further experimentation under varying scenarios for which MTI would be used, including field conditions, is needed to further validate the model and establish robustness. MTI wetting geometry informs placement depth for optimal irrigation water usage.

USING WASTEPAPER SLUDGE ASH (WSA) AS A MATERIAL FOR SOIL STRENGTHENING FOR THE CONSTRUCTION OF LAYERS OF PAVEMENT

The article considers the possibility of using wastepaper sludge ash (WSA) as a soil reinforcement material for the construction of layers of road wear. Loamy sand, sandy loam, silty clay loam, silty clay were chosen as soils for strengthening. The maximum density of the soil skeleton at optimum humidity was established by the method of Proctor. Wastepaper sludge ash and Portland cement grade 400 were used separately for soil strengthening. Six compositions of strengthened soil for each type of soil were investigated according to the strength criterion of water-saturated samples at the age of seven, fourteen and twenty-eight days. The research results indicate that wastepaper sludge ash can be used to strengthen different types of soils with the achievement of following grades of stabilized soil: M10, M20, M40.

Effect of Sources and Application Times of Nitrogen Fertilizer on Wheat Yield and Nitrate Leaching in Different Soil Textures

Aims Nitrogen fertilizers have destructive impacts on the environment through nitrate leaching. Methods To evaluate the effects of sources and application times of nitrogen fertilizer on wheat yield and nitrate leaching in different soil textures, an experiment was conducted using the factorial arrangement of randomized complete block design (RCBD). The treatments were two sources of nitrogen fertilizer including ammonium nitrate (AN) and urea (NN), applied three different times during the year with a control treatment: total application before sowing (T1), total application in spring (T2) and application of half the amount before sowing and half the amount in spring (T3) in different soil textures (sandy loam, silty clay loam and silty clay) with three replications during three growing seasons 2015-16 (Y1), 2016-17 (Y2) and 2017-18 (Y3). Results The results indicate that the effects of different soil textures in increasing grain yield differed significantly. The soil texture of silty clay loam compared to other soil textures (sandy loam and silty clay) differed in grain yield. Interaction effects of N sources and application times were significant at the 1 percent level for the three different soil textures. The results also showed that in the soil textures of sandy loam and silty clay at T3, compared to silty clay loam, grain yield increased. Silty clay loam with T2 increased grain yield compared to other soil textures, with a yield of 6863.6 kg ha-1. The effect of nitrogen fertilizer at different application times was significant in increasing the protein content in the silty clay and sandy loam. The protein percentage in the silty clay was 10.76 at T2 and was 10.93 at T2 in the sandy loam. In addition, AN compared to NN had a greater effect on the percentage of grain protein.Conclusion Nitrogen fertilizer application times affect grain yield and protein content in different locations. Moreover, AN increases protein content compared to NN. Maximum soil nitrate concentration was obtained at 80-100 cm depth in both fertilizer treatments and in sandy loam soil, and nitrate concentration increased during the experiment.

Aeolian-fluvial sediments and landscapes along the northwestern Negev Dunefield (Israel) margins since the late Pleistocene

&lt;p&gt;Dunefield margins are prone to changing domination between aeolian and fluvial systems. Dominating aeolian systems divert or block fluvial systems or/and reduce their erosional forces often leading to amplified sedimentation by a wide range of unique aeolian-fluvial (A-F) sediments. Other arid environments are mainly dominated by eroding ephemeral fluvial systems that usually characterized by sediment degradation.&lt;/p&gt;&lt;p&gt;The late Pleistocene encroachment of vegetated linear dunes into the northwestern Negev desert dunefield&amp;#160; (Israel) comprised a distinct period of aeolian domination upon ephemeral drainage systems originating in the loess-clad Central Negev highlands. This study analyzes the sediments, geomorphology and landscape evolution caused by A-F processes along dunefield margins, in particular sediments deposited by dune-dammed water bodies slightly upstream of the dunefield edge and between VLDs, using high-resolution field mapping, relative (portable) and absolute OSL dating, stratigraphy and sedimentological analyses. These sediments have been generally mapped as playa sediments, understood to be deposited in a fluvial-dominated environment.&lt;/p&gt;&lt;p&gt;Six main A-F sediment types were identified and interpreted: (a) Aeolian sand appears to be remnants of fluvial eroded VLD. &amp;#160;(b) Fluvial sand originates from dune erosion and deposited nearby. (c) Massive loam to silty-clay loam relates to abrupt changes in the hydraulic parameters (width/depth ratio and water losses through infiltration) which induce sudden change in flow velocity, resulting in unsorted massive deposits of upstream loess and other desert soil bedload. (d) Couplets, similar to the massive loam, contains loess and upstream sediments deposited in a standing water body. (e) Laminated silty-clay-loam units were identified only between VLDs. (f) High-energy fluvial deposits, which contain loam, sand and pebbles, with &amp;#160;a clear erosional boundary that mark the upstream edge of A-F sedimentation.&lt;/p&gt;&lt;p&gt;The landscape of the Negev dunefield margins developed since the late Pleistocene by short-term aeolian domination, which gradually changed into fluvial domination during the Holocene. Dune-damming depositions occurred during this transition. First outside the dunefield, then propagated downstream into the dunefield. Fluvial aggradation of A-F sediments resulted in a vast playa-like flats, that following dune-dam breaching underwent incision, let alone in small (~&lt;20 km&lt;sup&gt;2&lt;/sup&gt;) basins.&lt;/p&gt;

Soil quality of the tea and apple-growing sites in Mindat District, Chin state, Myanmar: A preliminary study

In this study, two sites from tea and apple growing sites were collected from Pyay village and Nine Mile village, Mindat district, Chin state of West Myanmar under a humid subtropical climate. The results of physicochemical properties of observed soils were neutral pH, favorable moisture, silty clay loam texture, very high content of organic carbon, organic matter and total nitrogen. However, the tea growing soil was very poor in phosphorus and potassium content. Moreover, both soils lack of available potassium. The content of heavy metals in both soils was not varied from each other and followed the order: Fe (iron) > Cu (copper) >Zn (zinc) > Pb (lead) > Cr (chromium) and was below the maximum allowed concentrations (MAC). Therefore, the studied soils are generally favorable for cultivation under the condition of application of phosphorus and potassium fertilizers. However, due to the regular application of fertilizers and pesticides, it is necessary to monitor these soils for PTE levels. Further research is recommended, which must include analyses of the physicochemical properties of soils to a two depths of 0-30 and 30-60 cm, especially for the area where fruit plants are grown. In addition, higher density of soil samples and sub-samples are necessary to produce a reliable dataset that will allow proper statistical analysis.

Effect of Intermittent Water Application from Trickle Source on The Water Movement and Moisture Distribution in Layered Soil

The aim of this research is to study the effect of intermittent water application on the wetting pattern and soil moisture distribution for homogeneous and layered soils under trickle source. Thirty experiments were conducted to monitor the advance of the wetting front in the soil profiles. Measurements of soil moisture content were also made at selected locations to evaluate the moisture distribution in soil. Four types of soil profiles were built; the first was sandy loam soil, the second was silty clay loam soil, the third was (silty clay loam/ sandy loam) layered soil, and the fourth was (sandy loam/ silty clay loam) layered soil. Three water application rates were used for each soil profile. Three continuous or intermittent applications were used; continuous applications, equally intermittent applications, and different intermittent applications. In addition, several cylindrical infiltration tests were conducted to describe some characteristics of each soil. Empirical relations to predict each of vertical (under trickle source) and horizontal (at soil surface) wetting front advance were found in this study. Empirical relations to predict the percentage of applied water volume in horizontal strips as a function of soil depth and in vertical strips as a function of horizontal distance from the trickle emitter were also found. The study showed that the wetted soil volume increases as either the water application rate increases, or the intermittent application ratio increases. Also, it showed that the ratio of horizontal advance to vertical advance of wetting front increases as either the water application rate increases, or the intermittent application ratio decreases. The study demonstrated that the accumulated ratio of water application volume at a certain soil depth from trickle source increases as the intermittent application ratio decreases. Also, it demonstrated that the accumulated ratio of water application volume at a certain horizontal distance from trickle source decreases as the intermittent application ratio decreases.

Soil characterization and fertility assessment of char lands for increased cropping intensity and crop productivity

A study was done for soil characterization and soil fertility assessment in Char Latif and Char Monpura of Bhola District to identify suitable crops for increasing cropping intensity and crop yields. The soils of Char Latif were almost silt loam to silty clay loam in texture. Soil pH values were slightly alkaline in reaction. The organic matter contents were low to medium (1.23-2.53%), the total N very low to low (0.08-0.22%), available P low to very low (4.67-14.1µg g-1 soil), available S low to very high (4.02-156.8 µg g-1 soil) and exchangeable K low to optimum (0.138-0.311%), exchangeable Ca and Na very high in Char Latif areas. At Char Monpura areas, the soils were silt loam to silty clay loam in texture. The soil pH was neutral to slightly alkaline in reaction. The organic matter contents of the soil were low to medium (0.21-2.60%) and the total N contents were very low to low (0.03-0.18%). Available P contents were very low (2.40-6.65 µg g-1 soil). Available S contents were low to very high (4.02-156.8 µg g-1 soil). Exchangeable K, Ca and Na contents were medium to optimum (0.20-0.48 me%), in desired level (4.54-9.07me%) and very high level (1.64-5.14me%), respectively. The soils of both char land areas were normally erosive having low fertility and low water holding capacity. Generally, farmers of char lands cultivated local varieties of crops. As a result, crop yields are low. High yielding profitable crops and crop cultivation measures could be recommended for both of the Char Latif and Char Monpura areas. The findings could help the government and the other organizations to take proper steps for improving livelihood of the char peoples by improved crop varieties and management practices. Hence, there is great opportunity to increase crop production through intensification of crop cultivation with the selection of appropriate crop varieties and soil management at char lands. Progressive Agriculture 31 (1): 56-67, 2020