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The aim of this research was to study soil structural stability indices of clay loam soil treated with organic amendments, using High Energy Moisture Characteristic (HEMC). For this purpose, three sizes of soil aggregates (0.5-1, 1-2, and 2-4 mm) were treated with three rates (0, 1.5, and 3 %) of vermicompost and urban waste compost. After three months of incubation, water retention of the slow (2 mm hˉˡ) and fast (100 mm hˉ ˡ) wetted soil aggregates were measured at six pressure heads from 0 to 50 hPa, and HEMC stability indices such as Volume of Drainable Pores (VDP), Stability Index (SI), and Stability Ratio (SR) were determined. The results showed that only the stability of 0.5-1 mm aggregates was significantly (P< 0.01) affected by organic treatments. The stability indices were significantly influenced by the rates of amendments, and increased with increasing their rates. However, the type of organic amendments had no significant effect on stability of aggregates. The mean of VDP, SI, and SR decreased by increasing diameter of the aggregates and decreasing the rate of the organic amendments, due to breakdown of macro-aggregates and decrease of macropore fraction. In general, to increase structure stability of clay loam soil in arid regions of Iran, application of at least 3% organic amendments is recommended. [ABSTRACT FROM AUTHOR]

The objective of this descriptive and cross-sectional study was to evaluate the scaling and corrosion potential of groundwater resources of Kerman province (southeast of Iran) in 2015. The values of quality factors including carbonate, bicarbonate, calcium, magnesium, sodium, chloride, sulfate, hardness, alkalinity, pH and temperature were obtained and the Langelier, Ryznar, Puckorius and Aggression indexes were computed and corrosion and scaling potential of the groundwater resources were assessed. The results of this study showed that the most values of physical and chemical parameters were in the range of favorable limit to higher than permissible limits, except pH and temperature which were in the favorable limit. The concentration of sulfate, chloride, and sodium was higher than the standard limit at 34.48%, 31.03%, and 51.72% of samples, respectively. The results of this study showed that the index values in most of the studied areas were placed in the corrosion limits and the average of Langelier, Ryznar, Puckorius, and Aggression index were less than zero, >7.5, >6, and 10 to 12, respectively. The difference between corrosion and scaling potential was analyzed by the Chi-squared test and the results illustrated that most of the studied sites were classified in the corrosive group. The results of this study disclosed that the effects of sulfate and chloride concentration on the water quality, scaling, and corrosion potential were higher than other factors. The comparison of water stability indexes showed that the groundwater resource of Kerman province was corrosive. Therefore, it is suggested that the practice of continuously checking the important parameters and adjusting pH of water resources using lime could be proposed in order to control the corrosion phenomena. [ABSTRACT FROM AUTHOR]