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Increasing soil moisture storage capacity is a strategy that can be implemented to minimize the use of water in paddy rice cultivation. Organic materials from different sources have the potential to increase soil moisture storage and nutrient enrichment. An incubation study was conducted to evaluate the incorporation of five selected organic amendments—as follows: rice husk biochar (RHB), oil palm empty fruit bunch biochar (EFBB), compost (COMP), rice husk ash (RHA), and oil palm bunch ash (PBA), with a control (no amendment) on soil moisture storage and some chemical properties of soil. The soil was incubated with five amendments for 60 days and sampled at 15-day intervals. After completion of the incubation, a greater extent of gravimetric water content was observed from RHB (0.46 g g−1) and EFBB (0.45 g g−1) followed by compost (0.40 g g−1). The addition of organic amendments significantly influenced soil chemical properties. Maximum soil pH was altered by PBA followed by EFBB compared to its initial value (5.01). The inclusion of EFBB finally contributed to the highest amount of total carbon (7.82%) and nitrogen (0.44%). The addition of PBA showed the highest available P and exchangeable K followed by RHB when compared with the amendments. The results indicated that RHB, EFBB, and compost retain more soil moisture compared to ash sources and added soil nutrients, indicating their potential to improve the chemical and hydrological properties of paddy soil.

The physical, chemical and mineralogical characterization of the constituents of magnesium-rich synthetic gypsum produced in a rare earth-refining plant located in Gebeng, Pahang, Malaysia was conducted through elemental chemical analysis, scanning electron microscopy with Energy Dispersive X-ray (EDX)-analyzer, thermal analysis, X-ray fluorescence and X-ray diffraction. The crystalline nature of the by-product was studied using FTIR spectroscopy. Elemental analysis confirmed the presence of Ca and Mg, which are essential macronutrients required by plants and this Ca alongside the high pH (9.17) of MRSG may confer on the material a high acid neutralization capacity. From the result, it was observed that the studied by-product is a heterogeneous crystalline material comprising of gypsum (CaSO4.2H2O) and other major components such as calcium (magnesium) compounds (hydroxide, oxide, silicates, and carbonate) and sulfur. These aggregates may contribute to give an acid neutralization capacity to MRSG. The XRD study of MRSG indicated a high content of gypsum (45.4%), shown by the d-spacing of 7.609 Å (2-theta 11.63) in the diffractogram. The infrared absorption spectra of MRSG indicate close similarities to mined gypsum. The results of the characterization indicated that MRSG has valuable properties that can promote its use in amending soil fertility constraints on nutrient-deficient tropical acid soils.

The main objective of this research was to make the land capability classification of rained farming for major crops. The study was conducted in Katsina Central, Nigeria. In this study five land units were identified based on topography. Soil survey was conducted to each land units for exploration of physical and chemical characteristics of the soil. The results of soil analysis reveals that the study area is characterized by susceptibility to erosion and low in soil fertility which limit the land capability for multiple uses. The land capability classification was employed based on USDA classification system. The results depict that four land units were rated capable for rain fed farming of major crops under different management practices which account 75.26% of the total land covered of the study area While 24.74% is not capable no matter whatever management practice applied as such it is recommended for forestry. The land capability of the area can be improved through adapting appropriate measures.

Understanding the effects of cover crops and tillage on soil physical properties is important for determining soil productivity. This study was conducted at Lincoln University's Freeman Center, USA to evaluate the effects of tillage and cover crop management on soil hydraulic properties. The field site included three replicate blocks in a randomized complete block design with each plot measuring 21.3 m in length and 12.2 m in width. Treatment factors were tillage at two levels (moldboard plow tillage vs. no tillage) and cover crop at two levels (cereal rye (Secale cereal) cover crop vs. no cover crop). Soil samples were collected in late spring/early summer from each treatment at 10-cm depth increments from the soil surface to a depth of 40 cm using cores (76.2-mm diameter and 76.2-mm length). Soil bulk density was 13% lower with tillage compared with no-tillage. Volumetric water content was significantly higher at 0.0 and −0.4 kPa pressures with tillage compared with no tillage. Tillage increased the proportion of coarse mesopores by 32% compared with no tillage, resulting in 87% higher saturated hydraulic conductivity (Ksat). Cover crop increased the proportion of macropores by 24% compared with no cover crop; this can potentially increase water infiltration and reduce runoff. As a result of higher macroporosity, Ksat was higher under cover crop compared with no cover crop. This study demonstrated that tillage can benefit soil hydraulic properties in the short term, but these effects may not persist over time. Cover crops may slightly improve soil hydraulic properties, but longer term studies are needed to evaluate the long-term effects.

Water is usually the most limiting factor in agricultural grain crop production. Various agricultural management practices such as tillage and use of cover crops have the potential to influence water infiltration into soil. This study was conducted on a Waldron silt loam (fine, smectictic, calcareous, mesic Aeric Fluvaquents) soil to evaluate the influence of cover crop and tillage management on in situ infiltration. The field site included three replicate blocks in a randomized complete block design with each plot measuring 21.3 m (69.9 ft) length and 12.2 m (40.0 ft) width. The two treatment factors included cover crop at two levels (cereal rye [Secale cereale] cover crop [CC] versus no cover crop [NC]) and tillage at two levels (moldboard plow tillage [Till] versus no-tillage [NT]). Continuous corn (Zea mays L.) was grown. Infiltration rates were measured in all the treatments using a Mariotte system with single ring infiltrometers during the 2014 and 2015 growing seasons. Water infiltration parameters were estimated using the Parlange and Green-Ampt infiltration equations. Parlange and Green-Ampt models appeared to fit measured data well with coefficient of variation ranging from 0.92 to 0.99. In 2014, the saturated hydraulic conductivity (KS) parameter value determined from the Parlange model was 30.4 mm h-1 for NT, about 42% greater than Till. The KS parameter value determined from the Green-Ampt model was 25.9 mm h-1 for NT, about 54% greater than Till. In 2015, the sorptivity (S) parameter value determined from the Parlange model was 38.6 mm h-0.5 for CC, about 82% greater than NC. The S parameter value determined from the Green-Ampt model was 34.0 mm h-0.5 for CC, about 90% greater than NC. Cover crop management can increase water infiltration, which can improve soil quality and enhance the sustainability of crop production systems.

This project reports the utilization and vitrification of wastewater sludge (WS) and soda lime silica (SLS) glass via converting them into glass-ceramic materials. The vitrification method has been used and also exploited as a solution for the disposal of WS and SLS glass and to minimize any environmental hazards. The glass ceramics were prepared from a mixture of wastewater sludge and SLS glasses and melted at 1375 °C for 3 hours and quenched by pouring it into water to obtain a coarse frit. The frit glass was then crushed and sieved to 106μm and pressed into a pellet. The sintering process was performed at various temperatures between 700-1000 °C for 2 hours at 50 ºC intervals. The combination of WS and SLS provided a suitable chemical composition for the production of glass-ceramic. The resulting samples were then characterized using energy dispersive X-ray fluorescence spectrometer (EDXFS), differential thermal analysis (DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and laser flash apparatus (LFA). In this work, a thermal diffusivity measuring apparatus was used for measurement of thermal diffusivity (α) of glasses and glass-ceramics. The measurements of α were carried out at room temperature up to 300 °C with the intervals of 50 °C. Experimental results showed that α value for samples A (25%WS 75%SLS) are in the range of 0.386 - 0.767 mm2s-1, samples B (20%WS 80%SLS) are in the range 0.322 - 0.726 mm2s-1, samples C (15%WS 85%SLS) are in the range 0.3 - 0.66 mm2s-1, samples D (10%WS 90%SLS) are in the range 0.283 - 0.623 mm2s-1, and for samples E (5%WS 95%SLS) are in the range 0.24 - 0.615 mm2s-1. The changes of the nature of the crystallinity of the samples, heat treatment temperature and changes of the density value have been suggested to be responsible for the variation in the thermal diffusivity behavior. DTA study indicated that there were only inflection points of the endothermic peaks in the DTA curves of the glass samples. XRD analysi