Meisam Samadi; Abdolreza Bahremand; Ali Salajegheh; Majid Ownegh; Mohsen Hoseializade; Abolhasan Fathabadi
Abstract
In order to develop management plans for water and soil conservation, it is necessary to determine the sources of sediment production in watersheds. During the past three decades fingerprinting technique has been used extensively in determining the contribution of different sources of sediment. In this ...
Read More
In order to develop management plans for water and soil conservation, it is necessary to determine the sources of sediment production in watersheds. During the past three decades fingerprinting technique has been used extensively in determining the contribution of different sources of sediment. In this study, was carried out sediments fingerprinting and determine the contribution of each source to sediment production of the Toulbane watershed in Golestan province. To this end, 44 source samples were collected from forest, pasture, agriculture and bank erosion. Also 8 sediment samples were collected using Philips time-integrated sediment sampler. Afterward, the concentration of 34 geochemical properties was examined in the laboratory using the ICP device. Next, the optimal composite tracers were determined to discriminate sediment sources by using statistical tests including mass conservation test and Kruskal-Wallis. The contribution of different sources to sediment production was determined using the multivariate mixing model. Finally, the uncertainty in the case of a low number of data, was examined using the Monte Carlo method. As a result, after statistical tests, 12 tracers were selected as the optimal composite fingerprints. The bank erosion was main source to sediment production with 52.18% and the forest had the lowest contribution to sediment production with 4.39%. The contribution of agriculture and pasture was 33.23% and 10.21%, respectively. According to the uncertainty analysis, bank erosion is the most significant source to sediment production. Also, the high difference between the upper and the lower boundaries in different sources indicates high uncertainty.
Roya Vazirian; Hamid Reza Asgari; Majid Ownegh; Chooghi Bairam Komaki
Abstract
Understanding the relationship between soil and plant is essential for reclamation of degraded lands. In order to investigate the relationship between Atriplex halimus density with carbon sequestration the rangeland of Incheborun was studied. Soil samples were collected randomly by Auger in the depth ...
Read More
Understanding the relationship between soil and plant is essential for reclamation of degraded lands. In order to investigate the relationship between Atriplex halimus density with carbon sequestration the rangeland of Incheborun was studied. Soil samples were collected randomly by Auger in the depth of 0-30 cm of the soil profile in three different plant densities (<200, 200-400 and >400 stand per hectare) with 30 replications. The data were subjected to ANOVA using statistical software SPSS 21.0. Means were separated by T-test at P≤0.5. The results of this research showed that the soil organic carbon have ranging from 0.48 to 0.64 (with an average of 0.56%) in Atriplex plantation areas, while the organic carbon have ranging from 0.03 to 0.12 (with an average of 0.078%) in the control region.Therefore, plantation measures caused significant difference in soil organic carbon contents per unit area in Atriplex plantation areas as compared to that observed in the control area. Sequestered carbon in per unit is 26.27, 27.85 and 30.66 ton/ha respectively for low, medium and high Atriplex density areas. The results indicated that the rate of organic carbon as well as soil carbon sequestration increased with plant density. There were no significant difference among sequestered carbon and soil organic carbon values under those three different levels of densities, while significant difference were observed between three plantation areas and control area.
