The Impacts of Nanoclay on Sandy Soil Stability and Atmospheric Dust Control

Wind erosion and dust storms are main issues in arid and semi-arid regions. Application of soil stabilizer on unstable land might be an effective and sustainable strategy in arid and semi-arid countries to minimized harmful effects on environment and human health. The aim of this study was to assess the effect of using nanoclay for increasing soil stability, as a result of increasing in size of soil aggregation, and improving soil water holding capacity, as well as improving soil structure in sandy soil. An experiment was conducted with two treatments (0 and 3000 mg/l nanoclay were uniformly spread on the soil surface) in four replications on sandy soil, in Khara desert, nearly 100 km east of Isfahan, Iran. The annual rainfall is about 68/55 mm, mean annual ET0 is 2800 mm/year, and the elevation is 1450 m above sea level. Amount of soil erosion was measured with different wind velocity (31.0, 55.2 and 67.3 km h−1). An aggregation size and water retention of collected soil samples were measured by sieves and pressure plate, respectively. The results showed that the amount of soil erosion in nanoclay-treated soils was significantly different (P>0.05) in comparison with water-treated (control) soils. The volumetric water content at 100 KPa increased in nanoclay-treated soils compared to control treatment. Results also showed that the proportion of 0.25-2 mm aggregate (macroaggregate) significantly increased in nanoclay-treated soils. Based on aforementioned results, it can be concluded that application of nanoclay on soil surface is able to fix the sand and it has ability to cement the particles to each other, increase aggregation and reduce wind erosion. The results suggested that more attention should be directed towards using nanoclay on soil surface of unstable soil areas. That coild be an option for control of the atmospheric dust

The Impacts of Nanoclay on Sandy Soil Stability and Atmospheric Dust Control

Wind erosion and dust storms are main issues in arid and semi-arid regions. Application of soil stabilizer on unstable land might be an effective and sustainable strategy in arid and semi-arid countries to minimized harmful effects on environment and human health. The aim of this study was to assess the effect of using nanoclay for increasing soil stability, as a result of increasing in size of soil aggregation, and improving soil water holding capacity, as well as improving soil structure in sandy soil. An experiment was conducted with two treatments (0 and 3000 mg/l nanoclay were uniformly spread on the soil surface) in four replications on sandy soil, in Khara desert, nearly 100 km east of Isfahan, Iran. The annual rainfall is about 68/55 mm, mean annual ET0 is 2800 mm/year, and the elevation is 1450 m above sea level. Amount of soil erosion was measured with different wind velocity (31.0, 55.2 and 67.3 km h−1). An aggregation size and water retention of collected soil samples were measured by sieves and pressure plate, respectively. The results showed that the amount of soil erosion in nanoclay-treated soils was significantly different (P>0.05) in comparison with water-treated (control) soils. The volumetric water content at 100 KPa increased in nanoclay-treated soils compared to control treatment. Results also showed that the proportion of 0.25-2 mm aggregate (macroaggregate) significantly increased in nanoclay-treated soils. Based on aforementioned results, it can be concluded that application of nanoclay on soil surface is able to fix the sand and it has ability to cement the particles to each other, increase aggregation and reduce wind erosion. The results suggested that more attention should be directed towards using nanoclay on soil surface of unstable soil areas. That coild be an option for control of the atmospheric dust

Assessment of Two Soil Fertility Indexes to Evaluate Paddy Fields for Rice Cultivation

Assessing soil fertility is essential to help identify strategies with less environmental impact in order to achieve more sustainable agricultural systems. The main objective of this research was to assess two soil fertility evaluation approaches in paddy fields for rice cultivation, in order to develop a user-friendly and credible soil fertility index (SFI). The Square-Root method was used as a parametric approach, while the Joint Fuzzy Membership functions as a fuzzy method with adapted criteria definition tables, were used to compute SFI. Results indicated that both of the methods determined the major soil limiting factors for rice cultivation clearly, and soil fertility maps established using GIS (Geographic Information System) could be helpful for decision makers. The coefficients of determination (R2) for the linear regression between the two SFI values and rice yields were relatively high (0.63 and 0.61, respectively). Additionally, the two SFI were significantly correlated to each other (r = 0.68, p < 0.05). The study results demonstrated that both of the methods provide reliable and valuable information. Compared to the fuzzy method, the procedure of the parametric method is easier but may be expensive and time-consuming. However, the fuzzy method, with carefully chosen indicators, can adequately evaluate soil fertility and provide useful information for decision making