scholarly journals KARAKTERISTIK SIFAT FISIK TANAH PADA LAHAN BUDIDAYA UBI KAYU (Manihot Esculenta Crantz) DI DESA WOLOGAI TENGAH

AGRICA ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 23-33
Author(s):  
Mariana Umin ◽  
Agustinus J.P. Anasaga

Characteristics of soil physical properties are the diversity of soil conditions based on structure, texture, soil color, and soil moisture content. Features of the physical properties of the soil influenced by several factors, including poor land management, which results in a decrease in fertility levels that includes physical, chemical, and biological soil characteristics.The method used in this study is the sample cluster method. Consists of a small group of units and then randomly selected as a representative of the population, all elements in the chosen cluster used as research samples. This study aims to determine the physical characteristics of soil texture, soil structure, soil color, and soil moisture content in cassava (Manihot esculenta Crantz) in Wologai Tengah Village.The results showed that the texture of the soil in cassava soil dominated by clay texture. The structure of the angular lumpy ground, soil color 10 YR 2/1 Black, and 10 YR 2/2 Very Dark Brown and had a soil moisture content of 37.4%. This soil type is an ideal soil type or classified as fertile to cultivate cassava plants.

1983 ◽  
Vol 61 (1) ◽  
pp. 202-210 ◽  
Author(s):  
Olubukanla T. Okusanya

The causes of some observed variations in plant size and leaf morphology of populations of Luffa aegyptiaca were investigated experimentally. The effects of soil type, soil salinity, soil moisture content, and mineral nutrients on the germination and growth of this species were examined. The results indicate that variations in size and leaf morphology between the population groups earlier described probably were caused by variations in soil type and soil nutrients. Nitrate was responsible for variation in leaf colour, potassium for leaf invagination, and phosphorus and nitrate together for leaf texture. Nitrate also played a major role in the variation in leaf size while calcium played a subsidiary role. Within a single population, variations would possibly also be caused by differences in soil conditions, principally humus content, soil moisture content, and salinity. The wide adaptability exhibited by this species also helps to explain its distribution on a wide range of soils.


Author(s):  
Y. A. Unguwanrimi ◽  
A. M. Sada ◽  
G. N. Ugama ◽  
H. S. Garuba ◽  
A. Ugoani

Draft requirements of two animal – drawn (IAR) weeders operating on loam soil were determined in the study. The implements include a straddle row weeder and an emcot attached rotary weeder evaluated under the same soil conditions, using a pair of white Fulani breed of oxen. The animal draft requirement was first estimated from the animal ergonomics measurements. Using area of 0.054 hectare as experimental plot for each implement the draft requirement of each implement was investigated after taking soil samples for soil moisture content and bulk density determinations. The implements tested showed variation in their average draft requirement. The straddle row weeder had the highest value of 338.15 N respectively while the emcot attached rotary weeder had the lowest value of 188.12 N with 47.03%, respectively. The average soil moisture contents and bulk density were 13.0% and 1.46%/cm3, respectively.


2016 ◽  
Vol 80 (1) ◽  
pp. 189-197 ◽  
Author(s):  
MARY THERESA CALLAHAN ◽  
SHIRLEY A. MICALLEF ◽  
ROBERT L. BUCHANAN

ABSTRACT Pathogens in soil are readily mobilized by infiltrating water to travel downward through the soil. However, limited data are available on the horizontal movement of pathogens across a field. This study used a model system to evaluate the influence of soil type, initial soil moisture content, and field slope on the movement of Salmonella enterica serovar Newport across a horizontal plane of soil under flooding conditions. Three soil types of varying clay content were moistened to 40, 60, or 80% of their maximum water-holding capacities and flooded with water containing 6 log CFU/ml Salmonella Newport and Citrobacter freundii, the latter being evaluated as a potential surrogate for S. enterica in future field trials. A two-phase linear regression was used to analyze the microbial populations recovered from soil with increasing distance from the flood. This model reflected the presence of lag distances followed by a quantifiable linear decrease in the population of bacteria as a function of the distance from the site of flooding. The magnitude of the lag distance was significantly affected by the soil type, but this was not attributable to the soil clay content. The rate of the linear decline with distance from the flood zone was affected by soil type, initial soil moisture content, and soil incline. As the initial soil moisture content increased, the rate of decline in recovery decreased, indicating greater bacterial transport through soils. When flooding was simulated at the bottom of the soil incline, the rate of decline in recovery was much greater than when flooding was simulated at the top of the incline. There was no significant difference in recovery between Salmonella Newport and C. freundii, indicating that C. freundii may be a suitable surrogate for Salmonella Newport in future field studies.


2020 ◽  
Vol 13 ◽  
pp. 117862212094806 ◽  
Author(s):  
MJ Marques ◽  
M Ruiz-Colmenero ◽  
R Bienes ◽  
A García-Díaz ◽  
B Sastre

The study of alternative soil managements to tillage, based on the evidence of climate change in the Mediterranean basin, is of great importance. Summer and autumn are critical seasons for soil degradation due to the high-intensity, short-duration storms. Vineyards are vulnerable, especially on steep slopes. The particular effects of storms over the years under different soil conditions due to different management practices are not frequently addressed in the literature. The aim of this study was to examine the differences between runoff and soil moisture patterns influenced by 2 treatments: traditional tillage (Till) and a permanent cover crop. A shallow-rooted grass species Brachypodium distachyon (L.) P. Beauv. with considerable density coverage was selected as cover crop. This annual species was seeded once in the first year and then allowed to self-seed the following years. Tillage was performed at least twice in spring to a 10- to 15-cm depth and once in late autumn at a depth of 20 to 35 cm. Rainfall simulation experiments were performed, 1 year after treatments, using high-intensity rainfall on closed plots of 2 m2, located in the middle strips of the vineyard with different treatments. The effects of simulated rainfall experiments were determined in 3 different moments of the growth cycle of cultivar: (1) in summer with dry soils, (2) in early autumn with moderate soil moisture, and (3) in autumn with wet soils. During the 2-year trial, the soil moisture level in the soil upper layer (0-10 cm) was higher for Till treatment (14.1% ± 2.4%) compared with that for cover crop treatment (12.3% ± 2.0%). However, soil moisture values were more similar between treatments at 35 cm depth (12% ± 1%), with the exception of spring and autumn; in spring, water consumption in the cover crop treatment was the highest, and the moisture level at 35 cm depth was reduced (12%) compared with that for Till treatment (13%). In autumn, in cover crop treatment, higher water infiltration rate in soils led to higher soil moisture content at 35 cm (11%) compared with that of Till treatment (10%). The effects of simulated rainfall experiments on runoff and infiltration under different soil conditions and management practices vary seasonally. Runoff was significantly higher in summer for cover crop treatment (11%) as compared with that for Till management (1%), but significantly lower (3%) with wetter soils than for Till treatment (22%) in autumn. Thus, the simulation experiments with wet soils using cover crops produced higher infiltration rates and, consequently, the higher soil moisture content in the following days. The difference between seasons is attributed to the greater porosity of soil under Till treatment in summer, which resulted from the shallow plowing (10-15 cm depth), carried out to reduce moisture competition between weeds. The effect of traditional spring plowing was short-lived. The infiltration of water increased by cover crop treatment as compared with tillage in autumn both before and after ripping. Management practices did not influence wine parameters, as no significant differences were found between wine organoleptic characteristics in the duo-trio wine tastings, similarly, no differences were found for alcoholic degree, acidity, reduced sugars, and pH; however, a trend for a positive increase in polyphenol contents was noticed. Therefore, properly managed to avoid water shortages, cover crops can be recommended for soil protection in semi-arid environments.


2000 ◽  
Vol 40 (6) ◽  
pp. 843 ◽  
Author(s):  
J. S. Day

Poor and uneven emergence of seedlings decreases the efficiency of sesame (Sesamum indicum) seed production. In a glasshouse study, seedling emergence was reduced by low soil moisture content (less than 20%, w/v) and by waterlogging (common in soils with small soil particles). Watering events that failed to raise soil moisture content above 20% caused most seeds to germinate (more than than 80%), but only some of these seeds emerged from the soil (less than 50%). Gibberellic acid pre-treatment of seeds (50 or 1000 mg/L) failed to improve emergence of seeds from soils with an initial soil moisture content less than 20%. This result supports previous reports suggesting that gibberellic acid treatment does not influence seedling emergence, and may only be useful to overcome seed dormancy in those sesame varieties where dormancy is a problem. For maximum emergence it is recommended that sesame seeds be sown in non-waterlogged soils and that soil moisture content be maintained above 20% for a number of days after sowing.


Geophysics ◽  
1998 ◽  
Vol 63 (4) ◽  
pp. 1357-1362 ◽  
Author(s):  
Robert D. Jefferson ◽  
Don W. Steeples ◽  
Ross A. Black ◽  
Tim Carr

Repeated shallow‐seismic experiments were conducted at a site on days with different near‐surface moisture conditions in unconsolidated material. Experimental field parameters remained constant to ensure comparability of results. Variations in the seismic data are attributed to the changes in soil‐moisture content of the unconsolidated material. Higher amplitudes of reflections and refractions were obtained under wetter near‐surface conditions. An increase in amplitude of 21 dB in the 100–300 Hz frequency range was observed when the moisture content increased from 18% to 36% in the upper 0.15 m (0.5 ft) of the subsurface. In the time‐domain records, highly saturated soil conditions caused large‐amplitude ringy wavelets that interfered with and degraded the appearance of some of the reflection information in the raw field data. This may indicate that an intermediate near‐surface moisture content is most conducive to the recording of high‐quality shallow‐seismic reflection data at this site. This study illustrates the drastic changes that can occur in shallow‐seismic data due to variations in near‐surface moisture conditions. These conditions may need to be considered to optimize the acquisition timing and parameters prior to collection of data.


2021 ◽  
Vol 46 (1) ◽  
pp. 22-30
Author(s):  
A.F. Tola ◽  
A.M. Sedara ◽  
O.B. Olatunde ◽  
A.A. Babalola

A study was conducted to determine the effect of soil moisture content, dynamic load and wheel slippage in measuring traction. A single wheel test rig was developed to enable fundamental research on traction studies on tropical soil at the department of Agricultural and Environmental Engineering of Federal University of Technology, Akure. This facility consists of a moving carriage with a trolley that moves in either forward or reverse directions on rails well above a soil bin powered by 2.2 kW, three phase induction motor. The present facility set up was able to operate in either towing test mode for tire motion resistance studies or driving test mode for tire net traction and tractive efficiency studies. The test tire on the moving carriage was powered to rotate by a motor with additional pull provided by a cable-pulley mechanism connected to a tower with hanging dead weights. All controls on the moving carriage were activated from the main control console. The developed facility was successfully tested to determine tractive efficiency for narrow wheels at a particular inflation pressure on clay soil. The single wheel test rig facility worked well and the research indicates that wheel load, wheel slippage, soil moisture content and inflation pressure has great effect on traction efficiency. Traction efficiency decreased as the wheel load and wheel slippage increased. The developed single wheel testing facility can perform traction tests in controlled soil conditions to study the effect of soil, tire and moisture parameters on the performance of the system.


2020 ◽  
Vol 15 (2) ◽  
pp. 68-74
Author(s):  
Paardensha Ivy Chinir ◽  
Manoj Dutta ◽  
Rizongba Kichu ◽  
Sewak Ram

A field experiment was conducted to evaluate the effect of forest litter and its time of incorporation on soil physical properties. The study showed that plots with forest litter incorporated at 45 DBS (Days Before Sowing) had significantly higher soil moisture content as compared to those incorporated at 30 DBS after 30 and 60 DAS. However, the difference in the time of incorporation had no significant effect on soil moisture content at 90 DAS. At 30 DAS, application of forest litter @ 6 t ha-1 and 9 t ha-1 significantly increased the soil moisture content at a rate of 4.11 and 11.42 per cent, respectively over control. At 60 DAS, application of forest litter @ 3 t ha-1, 6 t ha-1 and 9 t ha-1 significantly increased the soil moisture content at the rate of 15.05, 17.26 and 25.65 per cent, respectively over control. At 90 DAS, a trend was noticed which showed that soil moisture content significantly increased at a progressive rate with each increase in the dose of forest litter application. At 90 DAS, the addition of forest litter @ 3 t ha-1, 6 t ha-1and 9 t ha-1 increased the soil moisture content @ 10.16, 17.84 and 22.20 per cent, respectively over control. The plots with forest litter incorporated at 45 DBS had significantly higher hydraulic conductivity, per cent aggregates and mean weight diameter as compared to those incorporated at 30 DBS. However, the difference in the time of incorporation i.e., at 30 and 45 DBS had no significant effect on bulk density, particle density and water holding capacity. Incorporation of forest litter @ 3 t ha-1, 6 t ha-1 and 9 t ha-1 significantly decreased the bulk density at the rate of 3.67, 8.65 and 14.14 per cent; while particle density increased at the rate of 2.59, 3.42 and 6.61 per cent, respectively when compared to control. The addition of forest litter @ 3 t ha-1, 6 t ha-1 and 9 t ha-1 resulted in a significant increase in water holding capacity and hydraulic conductivity at a rate of 3.72, 4.65 and 6.77 per cent and 24.13, 32.30 and 41.73 per cent, respectively over control. Further, the application of forest litter @ 3t ha-1, 6 t ha-1 and 9 t ha-1 significantly increased the per cent aggregate and mean weight diameter of the soil @ 1.77, 3.49 and 6.58 per cent 17.31, 26.28 and 41.35 per cent, respectively over control. The study revealed that incorporating 9 t ha-1 of forest litter at 45 DBS had the most beneficial effect on soil physical properties.


2011 ◽  
Vol 139 (12) ◽  
pp. 3848-3870 ◽  
Author(s):  
Clark Evans ◽  
Russ S. Schumacher ◽  
Thomas J. Galarneau

Abstract This study investigates the impact of abnormally moist soil conditions across the southern Great Plains upon the overland reintensification of North Atlantic Tropical Cyclone Erin (2007). This is tested by analyzing the contributions of three soil moisture–related signals—a seasonal signal, an along-track rainfall signal, and an early postlandfall rainfall signal—to the intensity of the vortex. In so doing, a suite of nine convection-permitting numerical simulations using the Advanced Research Weather Research and Forecasting model (WRF-ARW) is used. Of the signals tested, soil moisture contributions from the anomalously wet months preceding Erin are found to have the greatest positive impact upon the intensity of the vortex, though this impact is on the order of that from climatological soil moisture conditions. The greatest impact of the early rainfall signal contributions is found when it is added to the seasonal signal. Along-track rainfall during the simulation period has a minimal impact. Variations in soil moisture content result in impacts upon the boundary layer thermodynamic environment via boundary layer mixing. Greater soil moisture content results in weaker mixing, a shallower boundary layer, and greater moisture and instability. Differences in the intensity of convection that develops and its accompanying latent heat release aloft result in greater warm-core development and surface vortex intensification within the simulations featuring greater soil moisture content. Implications of these findings to the tropical cyclone development process are discussed. Given that the reintensification is shown to occur in, apart from land, an otherwise favorable environment for tropical cyclone development and results in a vortex with a structure similar to developing tropical cyclones, these findings provide new insight into the conditions under which tropical cyclones develop.


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