Changes study of the Soil Aggregates Stability using Application of Different Bentonite Rates of Conditioner

Soil is the basis of biological resources and life on the earth. Soil stability is one of the key indicators that it uses to evaluation of soil structure against soil erosion. Considering the importance of the aggregates stability in controlling soil erosion, increasing the particles diameter on the soil surface and making them granular can be one of the ways to presentation their movement and displacement by erosive factors. Bentonite conditioner as a mineral conditioner can play the effective role in changing the aggregates stability, especially in degraded soils. In order to carry out the present research, the mineral conditioner of bentonite was used at the levels of 30, 15 and 45 percent and in three repetitions after the rainfall simulator system to measurement the aggregates stability. The Excel and SPSS software were used to performance all statistical analyses. The mean, coefficient of variation, standard deviation and conservation percentage of the aggregates stability were calculated with the usage of bentonite conditioner. According to the conservation percent and the average aggregates diameter using bentonite conditioner at three levels of 15, 30 and 45 percent and based on sieves of 500, 250, 125, 100, 53, 38 and particles less than 38 micrometer, the results showed the average diameter of soil aggregates. The results of GLM and Duncan tests of the bentonite effect showed that this conditioner had the positive effects on aggregates stability. The results of the GLM test showed that bentonite had the significant effect on the variables of D10, D10/ D90 and sorting at level of 95 percent. Also, this conditioner was significant on the variables of D50, D90, D10- D90, D25- D75 and skewness at the level of 99 percent, but it had not the significant effect on the variable of D25/ D75 and kurtosis. Also, with results study of the Duncan results test can be said that the bentonite with level of 15 and 30 percent had the better effects on the aggregates stability and changes in the average aggregates diameter. The obtained results from this research showed that the bentonite conditioner can act as a soil amendment and protect the soil surface against raindrops by creating adhesion in the soil surface and finally reduce the soil erosion. Bentonite can be effective in controlling soil erosion due to its characteristics including formability, adhesion and water absorption. According to the results of the present research, it can be stated that the bentonite application is beneficial in erosion management and reduction and making executive decisions. Although the final conclusion depends on conducting more extensive research in natural fields.