JWSS - Journal of Water and Soil Science

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Solarization of field soil through mulching with transparent polyethylene sheets alone and in integration with farm yard manure (40 T/ha) and/or metalayl (25 kg/ha) during summer 1994-95 for five weeks in Isfahan resulted in an increase in temperature of 10 °C (± 1) and moisture preservation of up to 82%. Solarization effectively reduced foot-rot of cucumber (Phytophthora drechsleri) in the above treatments up to 88%, 96% and 95%, respectively.

Solarization, farm yard manure and their integration reduced the infection of Meloidogyne javanica up to 50%, 57% and 83% while plant parasitic nematodes were also reduced to 72%, 75% and 86%, respectively. The populations of free living nematodes increased only in farm yard manure and in integration with solarization by 30% and 53%, respectively.

Solarization effectively reduced the populations of almost all weeds by around 100%, except for Cyperus rotundus and Sonchus asper which were reduced by 59% and 44%, respectively.

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Low calorie salad dressings are oil-in-water emulsion products, in which the oil content has been substantially decreased. This decrease, however, is accompanied by reduction in the viscosity hence, an undesirable texture. To overcome this, oil replacers are generally used. In this research, maltodextrin and xanthan gum were used to replace part of the oil in the production of two kinds of salad dressings mayonnaise and three Italian salad dressing. Various formulations of these products with varying amounts of oil, maltodextrin and gum at different temperatures were produced. Viscosities in the range of 50-140 Pa.s for mayonnaise and 2-15 Pa.s for Italian dressing were accepted as positive criteria and samples in these ranges were chosen for organoleptic and microbial tests. The results showed that in the formulation of mayonnaise, simultaneous increase in the amount of oil, maltodextrin and gum created a high viscosity, but the temperature did not play any significant role. In the Italian salad dressing, the increase in the amount of gum was accompanied by development of pseudoplastic characteristics which was not desirable, hawever, the effect of temperature on providing acceptable texture was found to be important. Although the formulated mayonnaise enjoyed a fairly acceptable quality, the Italian salad dressing samples, were ranked superior to the common Italian salad dressing available in the Iranian market. .

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The objective of the current research was to prioritize effective factors in landslide occurrence and its susceptibility zonation using Shannon’s entropy index in North of Tehran metropolitan. To this end, 528 landslide locations were identified using satellite images such as Geoeye (2011-2012), SPOT-5 (2010), and field surveys, and then landslide inventory map was created for the study area in ArcGIS environment. Data layers such as slope degree, slope aspect, plan curvature, altitude, lithology, land use, distance of road, distance of fault, distance of drainage, drainage density, road density, sediment transport index (STI), stream power index (SPI), topographic wetness index (TWI), normalized difference vegetation index (NDVI), surface area ratio (SAR) and topographic position index (TPI) were created and the mentioned maps were digitized in GIS environment. Prioritization of effective factors by Shannon’s entropy index showed that the layers such as land use, lithology, slope degree, stream power index, and NDVI had the most effect on landslide occurrence. However, factors of topographic position index and plan curvature had the least effect. Also, landslide susceptibility zoning by the mentioned model and its accuracy assessment using relative operating characteristics (ROC) curve and 30 percent of landslide locations showed an accuracy of 82.83% with a standard error of 0.0233 in the study area.