Esmaeil Silakhori; Hamid Niknahad gharmakher; Abdolbaset Aghtabye
Volume 25, Issue 1 , April 2018, , Pages 63-77
Abstract
In order to develop a clear and realistic desertification control plan, identifying and evaluation of processes as well as causes and current status of desertification are the basic needs of arid zones. In present study, the desertification assessment of Incheh – broun area in ...
Read More
In order to develop a clear and realistic desertification control plan, identifying and evaluation of processes as well as causes and current status of desertification are the basic needs of arid zones. In present study, the desertification assessment of Incheh – broun area in Golestan province was performed using three indicators of ESAs model (soil quality, vegetation cover quality and climate quality). Therefore, the map of each indicator was obtained from the geometric mean of its layers. From the geometric mean of these indicators and by classification of obtained map, the desertification sensitivity map of the study area (ESAI) was obtained. Finally, the study area was classified in three classes [no sensitive (7.64%), fragile (14.41%) and critical (77.95%)]. The results demonstrated that poor drainage, heavy texture of soil, poor vegetation cover, besides climatic factor are the most important factors of desertification in the study area causing desert conditions. With regard to the results and in order to prevent the advance of desertification processes, the biological and mechanical land improvement techniques such as plantation of species resistant to heavy and saline soils and construction of drainage in water logging lands are recommended.
Hamid Niknahad; Abdolbaset Aghtabye; Mousa Akbarlou
Volume 24, Issue 4 , January 2018, , Pages 708-718
Abstract
In view of the increasing adoption of rangeland exclosure in order to rangeland improvement and carbon sequestration, investigation of its effects on the soil properties and calculation of the economic value of sequestered carbon is important. The aim of this study was to evaluate ...
Read More
In view of the increasing adoption of rangeland exclosure in order to rangeland improvement and carbon sequestration, investigation of its effects on the soil properties and calculation of the economic value of sequestered carbon is important. The aim of this study was to evaluate the changes in some soil physico-chemical properties, carbon sequestration rate and its economic value following grazing exclosure as compared with open grazing areas in Bozdaghi rangelands in North - Khorasan province, Iran. Therefore, in each area (exclosure and open grazing) three transects of 500 meter length and 200 meter intervals) were set up. Along each transect, five soil samples were taken at the depth of 0–15 cm in a random – systematic method (15 soil samples in each area) and transferred to the laboratory. In the laboratory, some soil physical and chemical properties such as soil texture, bulk density, porosity, saturation percentage, pH , EC , percentage of organic matter, total nitrogen, the amount of cation exchange capacity, exchangeable sodium, potassium, calcium, and magnesium were measured and erodibility index was calculated by using the modified clay ratio relation. Data analysis was performed by using independent t test in SPSS v.16 software. The results demonstrated that establishment of exclosure in Bozdaghi rangelands had significant positive effects on soil physico-chemical properties, and reduced the soil erodability index significantly (P< 0.05). The mean value of sequestered carbon in the soil of exclosure area was significantly higher than that of open grazing area (P< 0.05) and its economic value was estimated to be 4709760 toman per hectare. According to the results, especially the high economic value of sequestered carbon in the soil of exclosure area, establishment of exclosure in the study area is recommended.