Effects of rice husk application on mechanical properties and cultivation of a clay soil with and without planting

In this study, effects of rice husk (RH) application on mechanical properties and cultivation of a clay textured soil were investigated with and without barley planting. A rate of 5% (w/w) rice husk as a dry weight basis was added to a clay textured soil by alone (RH) and with 5 kg N/da of ammonium sulphate (RHN) in order to increase the biological activity and the decomposition rate of rice husk in soil. Rice husk applied soils including control treatment were incubated at field capacity under greenhouse conditions for 2 months. After this period, barley was sown in a half number of the pots. All pots having barley planted and without planted were incubated together for 6 more months. Study was carried out in a factorial experimental design on barley planting and without planting pots in 3 treatments (control, RH and RHN) with 3 replications. At the end of the study, liquid limit (LL), plastic limit (PL), plasticity index (PI), consistency index (Ic), field capacity (FC), permanently wilting point (PWP) and organic matter (OM) contents of soils were determined. The highest values were determined for LL in RH+nitrogen+barley planting (RHNP), for PL in RH application without planting and for PI in control application with barley planting (CP). Barley planting increased LL and PI values of soil significantly. LL values of soils significantly correlated with PL (0.664**), PI (0.880**) and PWP (0.948**). PL values of soils significantly correlated with OM (0.699**) and PWP (0.821**). PI values of soils significantly correlated with FC (0.654**) and PWP (0.713**). Ic values gave the significant correlations with PL (0.908**), OM (0.787**), FC (-0.611**) and PWP (0.615**). Ic values in all RH treatments were higher than that in control treatments. It was concluded that clay textured soil in control treatment can have deformation when it is cultivated at the field capacity without RH application; however clay soils can be cultivated without deformation after application of RH

Aktif Öğrenme Yaklaşımına Dayalı Hazırlanan Okul Öncesi Eğitim Programının Çocukların Sosyal Yetkinlik Düzeylerine Etkisi

DergiPark: 625860tredÖğrenen ve öğretenaçısından yarattığı etki nedeniyle ilgi çekici olan aktif öğrenme, sosyaletkileşimi temel alan, öğrenenin ihtiyaçlarına odaklanan ve bu ihtiyaçlaracevap vermeyi amaçlayan, öğrenenlerin öğrenme süreçleri ile ilgili sorumlulukalmalarına olanak tanıyan, bir yaklaşımdır. Çocukların gelecekteki yaşamlarıiçin belirleyici olan sosyal yetkinlik düzeylerinin geliştirilmesi amacıyla,erken çocukluk döneminde önleyici programlar ortaya koyup, uygulanmasınısağlamak büyük önem taşımaktadır. Buradanhareketle araştırmanın amacı, aktif öğrenme yaklaşımı ile hazırlanmış eğitimprogramının 5-6 yaş aralığındaki çocukların sosyal yetkinlik düzeyleriüzerindeki etkisini ortaya çıkarmaktır. Araştırmada ön-test ve son-testile kontrol ve deney gruplu yarı-deneysel desen kullanılmıştır. 16 öğrencidenoluşan deney grubuna aktif öğrenme tekniklerini içeren 15 oturumluk eğitimprogramı uygulanıp, “sosyal yetkinlik ve davranış değerlendirmeölçeği” ve görüşme formları ile gerekli veriler toplanmıştır. Eldeedilen veriler incelenmiş olup, son testlerde deney grubu lehine anlamlı farklılıkgözlenmiştir

Crystallization of polyethylene under low gravity conditions: Implications for continued microgravity research on polymers

Linear polyethylene is a macromolecular system well suited for microgravity research; it has neither steric hindrances, sidegroups, polar moieties nor toxicity constraints peculiar to many organic systems. This research has centered upon determination of the effects of convection on the solidification of non-Newtonian fluid systems. Initial research served to identify the viability of polymer systems for low gravity processing affects. These investigations served to resolve gravity-induced variations in both solidified thickness and nucleation sites for thin (10 micron) melt/solidified polyethylene samples. Further, a variation in the birefringence of the solidified sample, correlatable to solidification gravity conditions but independent of nucleation sites or solidification thickness, demonstrated that morphological variations occurred during solidification that were resultant of gravitational fields. To investigate these minute effects a furnace was designed and fabricated and flown on the NASA microgravity aircraft: KC-135. The significant features of the furnace were the directional solidification aspects (eliminating gravity induced nucleation site variations), translation of the sample at its growth rate (allowing optical interface monitoring and reducing secondary nucleation concerns) and use of monitoring equipment (thermal, interferometric, acceleration and microscopy). Rheometric Dynamic Spectroscopy (RDS) was used to define the non-Newtonian nature of the polyethylene. The flight results were reviewed and hundreds of frames of interferometry data were reduced, and calibrated against thermocouple and accelerometer results. Analysis, using a computational fluid dynamics code was performed. A comparison of predicted results to empirical data for thermal gradients, flow velocities and crystallization conditions, assuming two gravitational conditions (10\sp{-4} and 1 g- level) and two viscosity assumptions (no shear thinning and with RDS data shear thinning) was performed. The results from these studies show that the pursuit of microgravity crystallization of polymer systems is both viable and warranted assuming appropriate experimental goals and analytical tools. Specific test results indicate that gravitational forces are correlatable to thermal variations during solidification, and these variations appear correlatable to post crystallization morphology. Further, analyses of non-Newtonian fluid system crystallization processes must include viscoelastic assumptions

Using soil moisture constants and physical properties to predict saturated hydraulic conductivity

Saturated hydraulic conductivity (Ks) is an important variable in hydrological cycle processes. Determination of Ks in soils is a difficult and time consuming process. The objective of this study was to determine Ks in soils by pedotransfer (PTF) models derived using soil moisture constants and physical properties. Ks values were determined in 30 different soil samples using constant head permeability method. According to path analyses results, direct effects of some soil properties on Ks in soils were in the following order; permanent wilting point (PWP) > bulk density (BD) > clay (C) > silt (Si) > field capacity (FC). Soil physical properties generally had the highest indirect effects on Ks through PWP. Prediction of Ks by the second order PTF models was significant using only C, Si and DB (r=0.868**) and using only FC and PWP (r=0.796**) in the models. Using moisture constants with the other soil physical properties in the second order PTF model increased significance level of the relation between predicted and measured values of Ks (r=0.955**). Besides soil physical properties, having moisture constants in PTF models showed that saturated Ks values can be predicted more accurately in soils having similar physical boundary conditions such as texture, bulk density etc

Assessment of soil quality for vineyard fields: A case study in Menderes District of Izmir, Turkey

This study was carried out to determine the suitable classification of soil quality for vineyard fields of Akçaköy, Çatalca, Efemçukuru, Görece and Yeniköy villages in Menderes district of Izmir-Turkey. In vineyard fields, soil pH gave a positive relation with Ca and significant negative relations with P, Fe, Mn and Zn contents. Soil organic matter (OM) content had significant positive relations with EC, P, Fe, Mn and Zn and significant negative relations with bulk density and CaCO3 content. Soil quality index values for the vineyard fields varied between 0.38 and 0.85 with a mean of 0.57. Only one of the 28 soil samples taken from different vineyard fields was found in very suitable (S1:1.00-0.75) class, 8 in suitable (S2:0.75-060), 12 in marginal suitable (S3:0.60-0.50) and 7 in non-suitable (N:<0.50) class according to the soil quality index (SQI). Restricting soil factors for vine growth in the fields classified in S2 and S3 classes generally became low pH, low organic matter (OM), P, Fe, Mn, Cu, Mg and K contents than that of suggested levels. In addition to restring factors in S2 and S3 classes, physical properties in soils classified in N class were lower than suggested levels. The SQI values showed significant positive relations with grape yield, soil OM, P, K, Fe, Cu, Mn, Zn contents and significant negative relations with soil pH, exch. Ca and CaCO3 contents. The grape yields had also positive relations with soil OM, Fe, Mn, Zn contents and negative correlations with soil pH and CaCO3 content. Soil quality in a vineyard field should be assessed to reach successful sustainable and precision agricultural practices for high crop production

Effects of rice husk compost application on soil quality parameters in greenhouse conditions

Effects of rice husk compost (RHC) on some soil quality parameters under greenhouse conditions were investigated. Experiment were conducted in a randomized plot design with different application doses of RHC (0, 3, 6 and 9%) into surface soil (0-20 cm) with three replications in a greenhouse of Agricultural Faculty in Ondokuz Mayıs University. RHC application generally improved the soil quality parameters according to the control treatment during the experiment carried out with growing tomato plant in the greenhouse in 2010. The soil organic matter (OM) contents significantly increased by the application of RHC in the following order; 9%>6%>3%>0%. While RHC applications in the greenhouses significantly reduced pH contents of soils according to the control, the RHC application increased the values of respiration rate (CO2), EC, NO3-N and available phosphorus (P). While the exchangeable Ca values of soils generally decreased, the exchangeable Mg and K values generally increased according to the control with RHC application. Bulk density (BD) values in the greenhouse were reduced with RHC application doses in the following order 0%>3%> 6%>9%. The values of field capacity (FC), permanent wilting point (PWP) and available water capacity (AWC) generally increased according to the control with the application of RHC dosses in the following order 9%>6%>3%. The highest positive correlations among the physical, chemical and biological properties were found between OM and PWP (0.924**), AWC and FC (0.907**), OM and FC (0.897**), CO2 and PWP (0.862**), PWP and FC (0.791**); while the highest negative correlations were found between BD and FC (-0.854**), BD and PWP (-0.871**), BD and OM (-0.868**), BD and CO2 (-0.838**), BD and P (-0.821**), Ca and FC (-0.812**). The highest tomato yield (7.77 ton/da) was obtained with the 9% of RHC application. RHC application to the soil in greenhouse generally improved soil quality and tomato yield

Changes in penetration resistance of a clay field with organic waste applications

Effects of manure (M), hazelnut husk (HH), tobacco (TW) and tea (TEW) wastes on penetration resistance (PR) values in a clay field were determined after 8 months of organic wastes were incorporated into soil at four different rates (0, 2, 4 and 6 %) in a randomized plot design with three replicates. While bulk density (BD), relative saturation (RS) and PR values decreased, mean weight diameter (MWD), total porosity (F), gravimetric water (W) and organic matter (OM) contents of the clay soil increased with increasing the application rates of organic wastes. While the lowest PR (0.72 MPa) was determined in the highest application rate of HH which had the highest C:N ratio, the highest PR (1.72 MPa) was in the control. According to the control treatment, decreases in mean values of PR by the organic waste applications were in the following order; HH (52.10%) > TEW (42.07%) > TOW (30.73%) > M (25.17 %). PR values gave significant negative correlations with F (-0.551**), W (-0.439**) and MWD (-0.509**), and significant positive correlations with BD (0.550**) and RS (0.374*). Total porosity showed the highest direct effect (62.39%) on PR. The higher indirect effects of the other properties on PR were also obtained via F. Applications of the same doses of different organic wastes had different effects on the PR values with changing the structure of clay soil due to their C:N ratios

Determination of Distribution and Properties of Soil Formed on Different Fluvial Deposit

Alluvial land, formed on accumulated sediment depositions by time, show large variety in their properties at short distances. Therefore, different soils can be form on these lands. The objective of this research was to determine, mapping and classify different soils formed on fluvial land used for intensive cultivation in Örencik village of Samsun Bafra district. Total study area is approximately 407.9 ha. Average annual temperature and precipitation are 13.6 oC and 764.3 mm, respectively. After examination of topographic, land use, geologic and geomorphologic maps and land observation, 9 profile places were excavated in study area. Detailed land observations were done with grid method and auger examinations. The soil samples were taken from each profile and their analyses were done in the laboratory. By assessing the results of analyses and field studies, 7 different soil series were determined and described. Three of them were classified as Entisol due to their young age, three of them were classified as Inceptisol and one is as Vertisol. Whereas Cevizlik series has the largest area (24.7%), Elmacıdede series has the smallest area in the study area (7.8%)

The Determination of wetting depth of soil in irrigation

Knowing wetting depth of soil is an important factor to determine the irrigation water amount depends on the development of plant root system in vegetation period. In this study, wetting depth of soil in corn grown area was estimated according to active soil layer, irrigation water amount, soil moisture change and field capacity using mathematical approach. In 40, 50, 60, 70, 80 and 90 cm soil layers, “wetting coefficients” and wetting depths for irrigation water amount of 900 m3 ha-1 were determined as 1.62, 1.43, 1.26, 1.13, 1.02, and 109, 116, 109, 95, 84 cm, respectively. In the same soil layers, “wetting coefficients” and wetting depths for irrigation water amount of 950 m3 ha-1 were determined as 1.71, 1.51, 1.33, 1.19, 1.07 and 119, 128, 122, 106, 94 cm, respectively. As a result, it was determined that basic factors effecting on wetting depth in irrigation were irrigation water amount and depth of active root zone

Clay activity index as an indicator of soil erodibility

ctivity index (AI) value characterizes the relationship between the plasticity index and clay content. In this study, AI value was investigated to determine whether it might be used as an indicator of soil structural stability or not. The AI values of 75 soil samples gave the significant negative correlations with their dispersion ratio (DR), soil erodibility factors (K) and erosion ratios (ER). Also, the AI values of the soils including clay and sandy clay loam textural class showed significant positive correlation with soil structural stability index (SSI). It seems that the AI value may be used as an indicator of soil structural stability