H. Dehghan-Menshadi, M. A. Bahmanyar, S. Salek Gilani, A. Lakzian,
Volume 16, Issue 60 (7-2012)
Abstract
Biological indicators are considered soil quality elements, due to their dependence on soil organisms. In order to investigate The effect of compost and vermicompost enriched by chemical fertilizers and manure on soil organic carbon, microbial respiration, and enzymes activity in basil plant's rhizosphere, a field experiment was conducted as a split-plot design with randomized complete blocks and three replications in 2006. The main plot involved six levels of fertilizer including: 20 and 40 tons of compost enriched, 20 and 40 tons of vermicompost enriched per hectare, chemical fertilizer and control without fertilizer and sub-plot, and period of application (two, three and four years). The results showed that application of compost and vermicompost at all levels increased soil organic carbon (OC) and soil microbial respiration, microbial biomass and urease activity compared to the controls (p<0.05), but increasing trend among the treatments was not similar. The maximum amounts of OC, soil microbial respiration and enzyme activity were observed in 40 tons of vermicompost enriched with chemical fertilizer ha-1 with four years of application. In high levels of compost application, the urease activity was decreased.
A. Koochekzadeh, H. Hoveizeh, A. R. Yazdipour,
Volume 22, Issue 4 (3-2019)
Abstract
Since 2001, water main drainage of sugarcane farms located in the east side of Karoon River has been deviated to Shadegan lagoon. The average discharge and salinity of the drain water in spring and summer were 20 and 20.5 m3 sec-1 and 17.1 and 13.3 dS m-1, respectively. Therefore, there have been considerable changes in the lagoon water quality when compared to the time before entering the drain water. Therefore, an experiment was performed to investigate the effects of sugarcane waste water on the quality of Lagoon’s water. The results showed that the average salinity was increased significantly before and after the entrance of the drainage into different points. The average salinity in the sample point No.2 (along the entrance of the drainage) in summer was changed from 17.7 to 51.5 dS m-1. The results, therefore, revealed that after the entrance of drainage water to Lagoon, during summer time, water salinity and mineral concentrations were increased for all locations except the points of 1 (on the northern margin of Lagoon) and 3 (influenced by Jarahi River). Phosphate ion concentration was increased at all investigated locations, but the highest phosphate concentrations were observed at the location points of 1 and 2 in summer. Given the important role of this lagoon in the protection of animal and plant spices, it is essentially important for sugarcane production companies to adopt a special measure for the protection of Lagoon from any source of pollution.
