Showing 2 results for D. Nikkami
Kh. Jalili, S. H. R. Sadeghi, D. Nikkami,
Volume 10, Issue 4 (winter 2007)
Abstract
Improper management of watershed land utilization has many ill effects on the available resources. Land use optimization is one of the proper strategies to achieve sustainable development and to reduce resource dissipation. Focusing on Brimvand watershed in Kermanshah province which comprises an area of 9572 ha, the present study was conducted to find out the most suitable land allocation to different land uses viz. garden, irrigated farming, dry farming and rangeland to achieve soil erosion minimization and benefit maximization. The soil erosion, net benefit and standard land capability maps were supposed as the inputs of the objective functions and to defined constraints. The multi-objective linear problem was then solved using simplex method with the help of ADBASE software package and ultimately the optimal solution was gained. Additionally, the results of the study revealed that the amount of soil erosion could reduce by 7.78% whereas the benefit increases at the rate of 118.62%, in case of implementation of optimal solution. The above mentioned optimization led to dry farming decrease and garden increase over that area. The results of sensitivity analysis also showed that objective functions were strongly susceptible to the variation of maximum constraint of irrigated farming and garden areas.
N. Khorsandi, M. H. Mahdian, E. Pazira, D. Nikkami,
Volume 15, Issue 56 (sumer 2011)
Abstract
Rainfall erosivity force as on important factor in soil erosion and sediment yield has been introduced in different indexes. The objective of this study was to determine suitable rainfall erosivity indices for two climates of semi-arid in Maravetape and very humid in Sangdeh, both in Khazar watershed, by correlation between rainfall erosivity indices and sediment outflow from erosion plots. For this purpose, the rainfall intensities in different time steps and the amount of rainfalls of 12 events in Maravetape and 11 events in Sangdeh have been used. Twonty five rainfall erosivity indexes were calculated based on rainfall intensity. The amount of soil loss measured after each rainfall event in 1.8×22.1 m2 erosion plots. The results of the study revealed that in very humid climate of Sangdeh and in semi-arid climate of Maravetape had high correlation of 0.803 and 0.727 (at the level of 99 percent) with sediment yield and they were applied indices in these climates of Khazar watershed. In general, the groups of 10 and 30 minutes are better than other erosivity indices in the study areas.
