Effects Study of Individually and Combinied of Soil Conditioners on Response of Soil Loss and Surface Runoff

 Nowadays, ths soil erosion is a serious threat for most societies and it causes the loss of water and soil. One of the most important factors of control of runoff and soil erosion is the application of soil conditioners. Therefore, the current research was conducted in order to performance evaluation of individually and combined effect of the bean straw mulch in three levels of 25, 50 and 75 percent and polyvinyl acetate in level of 3 percent on changes of runoff and soil erosion.

 the used soil at present study collected from rangelands at depth of 20 cm and after transportation to laboratory for relative stability of aggregates passed from sieve of 4 mm. For performance of the present study of the treatments of bean straw mulch as an organic soil conditioner and polyvinyl acetate as an inorganic conditioner used in individually and combined form. The conservation treatments applied at laboratory conditions using rainfall simulator for time priodes of 24 h, 2 and 4 months.

The results showed that the bean straw mulch and polyvinyl acetate at individually and combined various levels and applied time intervals could increase the time to runoff and end runoff and also decrease the runoff coefficient, soil erosion and sediemt concentration. The most affect on time to runoff related to combined treatment of bean straw mulch with level of 75 percent + polyvinyl acetate (MSP3) at time interval of 2 month (with rate of 74.68 percent). Also, the maximum changes of reduction of soil erosion related the application of bean straw mulch with level of 75 percent (MS3) at time level of 2 month with rate of 67.54 percent. The results showed that the bean straw mulch and polyvinyl acetate had significant effect on studied variables at level of 99 percent.

In general, it can be stated that the usage of bean straw mulch and polyvinyl acetate with form of individually and combined with other conditioners in order to investigation their effects on soil and water conservation can be a useful method. Finally, the usage of bean straw mulch and polyvinyl acetate in eroding or eroded lands and performance of new researches with other soil conditioners and in different conditions recommended with aim of soil and water conservation. Also Due to the different performance of individually and combined application of bean straw mulch and polyvinyl acetate, the correct usage of conditioners is necessity at the resources management of water and soil.