Reza Siahmansour; Hossein Arzani; Mohamad Jafari; Seyed Akbar Javadi; Ali Tavili
Abstract
Fire consider as a factor and basic management in rangeland in order to reform of composition and biological diversity that use in rangeland ecosystems. This project was established to deal with the effect of fire in the research center for rangeland. Zagheh locale where is in 35 km of north eastern ...
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Fire consider as a factor and basic management in rangeland in order to reform of composition and biological diversity that use in rangeland ecosystems. This project was established to deal with the effect of fire in the research center for rangeland. Zagheh locale where is in 35 km of north eastern of Khoramabad with 1960 meters above sea level. The average comparison and analysis show that herbal forbs which use for grazing form density and average o canopy cover have significant difference at the level of %1 between fire and control area. (p < %1). This study shows that in short time, it is possible to replace perennial. The Prevailing type of grass such as Agropyron trichophorum - Bromus tomentellus and festuca ovina with annual grass like Bromus tectorum –Heteranthelium piliferum- Taeniatherum crinitum. These changes indicate perennial grasses and increased annual grasses in short time.
Nayereh Ghazanfarpour; Sadat Feiznia; Hassan Ahmadi; Mohammad Jafari; Masoud Nasri
Abstract
Estimation of the amount of soil loss measurement of field indicators is a low-cost method, is easy to learn and can be simply applied. In order to measure and make assessment of soil loss amount by field indicators method in Shahrak Watershed, first map of the work units was prepared and then, measurements ...
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Estimation of the amount of soil loss measurement of field indicators is a low-cost method, is easy to learn and can be simply applied. In order to measure and make assessment of soil loss amount by field indicators method in Shahrak Watershed, first map of the work units was prepared and then, measurements of the relevant field indicators were carried out within these units. Then, EPM model was calibrated and verified. Then the measured data for the amount of the soil loss obtained by using field indicators were analysed and assessed using EPM experimental model. Mean of relative error and correlation coefficient between values from filed indicators method and EPM model were around 7.6 and 0.9, respectively which these results verify field indicators method for estimation of soil loss intensity. Estimation of the average of soil loss amounts relevant to each of the field indicators shows the following soil losses: Rock exposure indicator: 47.61 (ton/ha), Pedestal indicator: 22.61 (ton/ha), Rill indicator: 5.67 (ton/ha), Sediment in drains indicator: 2.21 (ton/ha), Gully indicator: 2.17 (ton/ha) and Build up against barriers indicator: 34.78 (ton/ha).
Mohammad Jafari; Mohammad Tahmoures; Mohsen Naghiloo
Abstract
The purpose of this research is investigation of relationship between vegetation cover and soil characteristics and determination of the most important soil factor that effects on quantity variations and kinds of vegetation cover in the study area. The study area is located in west of Tehran province ...
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The purpose of this research is investigation of relationship between vegetation cover and soil characteristics and determination of the most important soil factor that effects on quantity variations and kinds of vegetation cover in the study area. The study area is located in west of Tehran province and south eastern of Hashtgerd, next to Najm-abad village. After field study, the index vegetation types were selected and randomized-systematic sampling method has been used for soil and vegetation cover sampling in each of key area. The area of each plot was determined according to kind of plant species and species distribution using minimum area method. Some vegetation cover parameters such as canopy cover percentage, density and frequency of plant species were measured in the area. Then soil sampling were done from 2 horizon 0-10 cm and 10-30 cm in each plot and soil attributes such as texture, pH, organic carbon percentage and gypsum were measured in soil laboratory. Afterwards statistical methods like multivariate regression, analysis of variance and statistical techniques were used for analyzing of soil and vegetation cover data. Results showed that there is not any specific difference between soil and vegetation data except for gypsum. In other words the effective factor on vegetation cover variation was soil gypsum.
khadijeh rahimi balkanlou; Mehdi Ghorbani; mohammad jafari; ali tavili
Abstract
One of the most important preparation steps of co-management projects implementation is recognizing key actors at local community level. These actors can assist managers and planners as local leaders and social powers. By applying social network analysis and centrality index at actors’ level of ...
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One of the most important preparation steps of co-management projects implementation is recognizing key actors at local community level. These actors can assist managers and planners as local leaders and social powers. By applying social network analysis and centrality index at actors’ level of “Goormomenin” common rangeland, Kalateh region, Daamghan city in this research, social powers and local leaders in co-management procedures were identified. By social network analysis system, in-degree, out-degree centrality and betweenness centrality at actors level were studied based on trust and cooperation matrices and a combination matrix. According to the results, one of the stakeholders “Go-Bi” is a key actor in this rangeland. Based on core-periphery index, central and peripheral actors and density were identified. Having much authority and social influence, actors at central group play key role in rangeland co-management. Before implementing natural resource management projects, recognizing these actors can help governmental organizations to develop trust among villagers so that propel successful co-management procedures. These people create bridging ties between public institutions and stakeholders in rural sustainable development plans.
Masoomeh Abbasi Khalaki; Mohammad Jafary; Ali Tavili; mehdi moameri
Abstract
To find the effect of Atriplex canescens on soil chemical properties, two adjacent areas, each with and area of 1 ha, were selected in Hossein Abad Hapeshloo Shahryar. In one area it was planted Atriplex canescens in 2003 while the later one without Atriplex canescens was considered as control area. ...
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To find the effect of Atriplex canescens on soil chemical properties, two adjacent areas, each with and area of 1 ha, were selected in Hossein Abad Hapeshloo Shahryar. In one area it was planted Atriplex canescens in 2003 while the later one without Atriplex canescens was considered as control area. To sample soil, random- systematic method was used along 3 transects with a length of 100 m. In planting site transects were established perpendicularly on furrows were while in control site they were established parallel. Along each transect, 3 profiles were dug in initiate, medium and end points of each transect under shrubs and samples were taken from two depths (0- 30 cm and > 30 cm). Then, soil characteristics including texture, pH, Ec, Lime (CaCo3), ESP, organic mater (OM) and elements of Na, K, Ca, Mg and N were measured in laboratory. The results of this study showed that pH and Mg were significantly reduced in planting site compared of control. In addition, Na, Mg, Lime and Ca were significantly increased in planting site in comparison to control.
Ali Golkarian
Abstract
Erosion is one of the important factors in soil degradation and decrease fertility and slope length is one of the most effective factors in land form and amount of erosion. The objective of this study was investigation of spatially variation of sediment concentration in slope length until to receive ...
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Erosion is one of the important factors in soil degradation and decrease fertility and slope length is one of the most effective factors in land form and amount of erosion. The objective of this study was investigation of spatially variation of sediment concentration in slope length until to receive transport capacity. To obtain this goal a hill slope simulator system designed and manufactured. This system include 10 flumes, each has five meter length which after series them become fifty meters. This system can produce cumulative flow via fifty watering can tube which are install on flumes with one meter interval and each flume discharging is 100 cc. Other variables include two type of soil and slope in three level 15, 22.5, 30 percent. Three replications were used for each treatment and totally 18 experiment was done. In each experiment four samples were gathered from end of each flume and concentration was determined. Complete randomized design with factorial arrangement was used for data analyzing. Richard’s function was used for fitting a suitable curve on observed data. Result was shown that effect of soil type on sediment concentration was not significant while slope and slope length effects was significant. Otherwise sediment concentration in the two last flumes was located in same class which is shown that sediment concentration achieved to transport capacity in this slope length. Also results were shown that Richard’s function can simulate trend of concentration variety in slope length.
TAYYEBEH MESBAHZADEH
Abstract
This research was done in order to submit a model for salinity map made with TM satellite data and salinity values in a Buienzahra. The necessary processings such as principal component analysis and producing of different indices was done on the main bands. The 38 soil samples using random sampling (with ...
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This research was done in order to submit a model for salinity map made with TM satellite data and salinity values in a Buienzahra. The necessary processings such as principal component analysis and producing of different indices was done on the main bands. The 38 soil samples using random sampling (with 10×10 km dimension) from different horizons were designed and performed on the study area. The position of each node was registered with global positioning system (GPS), and the surface electric conductivity of samples was measured using EC meter instrument in soil saturation extract. Correlation between spectral values (main bands, produced indices) with electrical conductivity values were investigated for 80% of the samples. The regression analysis of ECe showed that there is a significant correlation between ECe with spectral data in all of main bands and with BI, NDMI, SI1, SI2, SI3 indices in 99% levels. The accuracy assessment of estimations using validation 20% samples was done. Results showed the produced ECe model could predict the soil salinity with ME and RMSE of 0.08 and 2.53 dS/m respectively. At finally, Salinity map with different salinity classes ( 0-2, 2-4, 4-16, 16-32, 32< dS m-1) was produced.
Samaneh Razavizadeh; Ali Salajegheh; Shahram Khalighi Sigaroudi; Mohammad Jafari
Abstract
Land use change is one of the main factors in the process of changing the regime of flood in watersheds. Taleghan watershed has been subjected to many land use changes over years, which probably effects on flood characteristics of Taleghan River. In present study the effects of land use change on some ...
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Land use change is one of the main factors in the process of changing the regime of flood in watersheds. Taleghan watershed has been subjected to many land use changes over years, which probably effects on flood characteristics of Taleghan River. In present study the effects of land use change on some parameters including peak flow, volume and flood base time, in part of Taleghan basin, was investigated by using Geographical Information System (GIS) and HEC-HMS model. Land use maps of 1987 and 2002 were prepared and integrated with soil hydrological groups and pasture conditions maps in GIS with the aim of providing of CN map. Then by using curve number and SCS unit hydrograph in sub basins and also Muskingum routing method, HEC-HMS model was calibrated and validated, for 10 incident rainfall - runoff views. Results of the simulation showed that due to the changes in land use (the reduction in the level of agricultural lands and increases in pasture areas), peak flow and flood volume in 2002 than in 1987 showed the average reduction of 46% and 34%, respectively. The evaluation of base time of flood showed no change in the parameter in flood hydrograph at the study period. On the whole the results showed that the trend of land use changes have the positive effect on reducing flood productions in study area.
Ali Akbar Mehrabi; Mohammad Mohammadi; Mohsen Mohseni Saravi; Mohammad Jafari; Mehdi Ghorbani
Abstract
Providing of landing use maps and detecting of land capacity are required to manage of natural resources and environment and planning of land use. On the other hand, it is necessary to detect of the human deriving forces affecting land use change. In this research, we selected Seyed mohaleh and Drasara ...
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Providing of landing use maps and detecting of land capacity are required to manage of natural resources and environment and planning of land use. On the other hand, it is necessary to detect of the human deriving forces affecting land use change. In this research, we selected Seyed mohaleh and Drasara villages in Tonekabon city. First, were provided the land use maps in 1987 and 2008 by using TM and IRS Satellite images. Second, were investigated the human deriving forces affecting land use change through survey methods. According to results of this research can state that had been destroyed much percents of forests and added residential and agricultural lands in two villages. The most important of land use changes in two villages related to the economic problems (low income) and the economic loss of agricultural activities. Recently, the most important deterrent forces of land use changes are the property market downturn and land price that can prevent of severe changes in land use through the implementation of efficient land use law and supporting of farmers and gardeners in this region. Moreover, the most important indicators in the intensification of land use changes are being a tourist area, increasing of land price and unemployment.
