Ataolah Ebrahimi; valiollah Raufirad; Hosein Arzani; Zahra Shojaei Asadeiye
Abstract
Determination of rangeland species palatability has some functions such as defining the rangeland grazing capacity and plant composition estimation. Despite the importance of palatability in rangeland management, no appropriate palatability indicator has been defined yet. Therefore, developing an accurate, ...
Read More
Determination of rangeland species palatability has some functions such as defining the rangeland grazing capacity and plant composition estimation. Despite the importance of palatability in rangeland management, no appropriate palatability indicator has been defined yet. Therefore, developing an accurate, applicable, general, and simple indicator for plant palatability estimation seems crucial. This research is an effort in this regard. To investigate the relationship between plant secondary compounds and palatability, plant species composition in the study area and in the sheep and goat diet as well as selection index were measured using chronometric and filming method. In the next stage, main plants’ secondary compounds in livestock diet were determined using GC/MSS. Then plants’ secondary compounds were ordinated using principle component analysis (PCA) method. Quantitative value of each plant species Eigen values on each of the main axis of PCA was regarded as a criterion for differentiation of plant species based on its secondary compounds. Finally, correlation between selection index of each plant species by sheep and goat (as dependent variable) with each plant species Eigen values on PCA axis (as independent variable) was determined. The results showed that there is a significant negative relationship between the selection index of the species by sheep and goat with its secondary compounds (P≤0.05). So, it is concluded that secondary compounds are effective factors in animal’s diet selection for grazing. Therefore, secondary compounds are recommended as an important factor for plant palatability determination.
Alireza Amirian Chekan; Ferydoon Sarmadiyan; Ahmad Heydari; Mahmoud Omid; Jahangir Mohammadi; Inakwu Odeh
Abstract
The traditional fuzzy operators, such as t-norms, t-conorms and averaging operators have been used for soil suitability evaluation to aggregate criteria as an overall suitability index. However, such operators do not account for the degree of compensation common to human aggregation criteria, especially ...
Read More
The traditional fuzzy operators, such as t-norms, t-conorms and averaging operators have been used for soil suitability evaluation to aggregate criteria as an overall suitability index. However, such operators do not account for the degree of compensation common to human aggregation criteria, especially in the presence of conflicting criteria. Fuzzy integrals are powerful and flexible aggregation functions that combine the data provided by several information sources based on fuzzy measures. One of the most known fuzzy integrals is the Choquet Integral (CI) that is often used as a nonlinear aggregation tool that takes into account the interactions among the conflicting and interrelated criteria. CI has hardly ever been used in soil suitability evaluation. In this paper, we tested the CI performance as an aggregation operator to evaluate soil suitability for irrigated rice in Lorestan province, western Iran. To conduct standard fuzzy analysis, soil samples were taken from 29 farms under rice cultivation and for the purpose of validation, average dry matters of the three 1×1m quadrates were used to determine the grain yield of rice in each farm. Fuzzy membership values of seven evaluation criteria were combined using CI to obtain a single suitability index in each land unit. In order to validate the results, the soil suitability indices were tested and compared with the results obtained by Lukasiedwicz’s t-norm and t-conorm operator (CLO) by correlation with the measured rice yield. The results show R2 values were fairly high for both aggregated methods, but the soil suitability index obtained by the CI integral has significantly better agreement with rice yield (R2 = 0.83) than those obtained with the CLO (R2 = 0.75). These results call for further investigation of CI as an alternative, and perhaps a better, aggregation operator for soil suitability evaluation.
M Jafari; H Azarnivand; A Hajibaglo; E Alizadeh
Volume 63, Issue 3 , December 2010, , Pages 307-318
Abstract
This study investigates the relationship between litter quality and aerial parts of plant on C, N, K, P and C/N ratio of soil in four rangeland species including Agropyron intermedium, Bromus tomentellus, Eurotia ceratoides and kochia prostrata. After recognizing the sites of these species in Hamand ...
Read More
This study investigates the relationship between litter quality and aerial parts of plant on C, N, K, P and C/N ratio of soil in four rangeland species including Agropyron intermedium, Bromus tomentellus, Eurotia ceratoides and kochia prostrata. After recognizing the sites of these species in Hamand Absard located in 65 km of northern Tehran, at the end of growing season, samples of litter, aerial part of plants and soil were taken using systematic- random method. For this purpose, five transects, each of l00 m length and 50 m spacing were taken. Two plots in each transect with an area of 1 m2 were established. In each plot, soil samples under plants and without plant area (control samples) at depth of 0-30 cm were taken. The C, N, P, K, EC, pH and texture of samples were analyzed in laboratory. Analysis of variance, Dunnett's test and t-student test were applied to the data. Results show that in the aerial part of plant, C and C/N ratio of Agropyron intermedium and P, K and N of Kochia prostrata are higher than other species. In case of litter, C, K and C/N of Eurotia ceratoides and N and P of Kochia prostrata showed higher values. However the results of soil samples show that C of Agropyron intermedium, N and C/N of Kochia prostrata and K of Bromus tomentellus are higher than other species. Totally, Kochia prostrata showed the best litter quality, decomposition rate and effects on soil.
hamed eskandari; moslem borji; Mehdi Ghorbani
Abstract
Local initiatives have been defined as specific collective activities without external support or incentives in order to control either ground or surface waters. One of the most important of approaches in water resources management is community-based water management. Social structures of water resources ...
Read More
Local initiatives have been defined as specific collective activities without external support or incentives in order to control either ground or surface waters. One of the most important of approaches in water resources management is community-based water management. Social structures of water resources are one of the aspects of indigenous knowledge in the management of water resources and it is necessary to analyze the social structures associated with it. The main objective of this paper is to identify aspects of indigenous knowledge related to the sustainable water resources management in Roozkin Village - Sarduyeh- Jiroft County. In this study, based on anthropological methods and qualitative approaches, including direct and participatory observation and organized interviews with 32 informed respondents (farmers) was used. In Roozkin Village, a certain social structure governs on the management of water resources in the region dating back more than 100 years. Cooperation in water resources management is considered as fundamental principle in this village and the social roles of Arbab and Zaim are among social initiatives of this village in management of water resources. In this village, 10 associations or local groups have been formed for managing water resources and each group is composed of Arbab and Zaim. In general, it could be noted that indigenous knowledge and local traditions in the village are factors influencing on sustainability of water resources and also it could be concluded that they will be effective in the promotion of socio-ecological resilience in the face of environmental crises such as drought.
Massoud Borhani; rahele sadeghzade
Abstract
. This bulb root plant has essential oil with medicinal property. The great need for this product has led to a large harvest of its bulbs from the rangelands, which has significantly reduced its stands in recent years. The aim of this research is to determine the vegetative characteristics of Allium ...
Read More
. This bulb root plant has essential oil with medicinal property. The great need for this product has led to a large harvest of its bulbs from the rangelands, which has significantly reduced its stands in recent years. The aim of this research is to determine the vegetative characteristics of Allium hirtifolium in Isfahan province. For this purpose, The presence of the plant was determined using field studies of 1395, and the ecological characteristics including topographic(elevation and slope), meteorology (rainfall, temperature, and climatic classes) and soil (Texture, salinity and acidity) were determined. Also using logistic regression model, the main factors influencing the presence of the species were identified. This species occur mainly in Astragalus community. The results showed that the highest presence of the species is in cold semi-arid climate with an average annual rainfall of 300 to 500 mm and an average annual temperature of 11 to 14 ° C. In terms of topographic factors, the species presence is mostly at altitudes between 2400 and 3000 meters above sea level and slopes of more than 20 percent. In terms of soil parameters, this plant is mainly in medium soil texture with a pH of 7 to 8 and an electrical conductivity of zero to 4 dsi Siemens / m. The logistic regression model showed that the two factors of elevation and precipitation had the most effect on presence of species.on species presence showed that topographic and rainfall factors had the most effect on species presence.
Shafagh Rastgar; Ali Darijani; Hossein Barani; Mohammad Ghorbani; Jamshid Ghorbani; Vahed Bordi Sheikh
Abstract
Forage is the main product of rangelands. So, determining its economic value as one of the main important nonmonetary functions can help managers to improve planning and optimal utilization management of rangelands. The main purpose of this study is to estimate the economic valuation of the forage of ...
Read More
Forage is the main product of rangelands. So, determining its economic value as one of the main important nonmonetary functions can help managers to improve planning and optimal utilization management of rangelands. The main purpose of this study is to estimate the economic valuation of the forage of summer rangelands in Nour-roud watershed basin in Mazandaran province. Consequently, total forage production estimated by using double method in 12 unit works. According to the heterogeneity of range forages in terms of economic and lacking organized market for transaction, have been used barely and using Replacement Cost Method (RCM). In order to homogenize the value of all forage plants, Total Digestible Nutrients (TDN) of each plant multiplied to its forage product to calculate the nutrition value of forage per rangeland unit work. According to the specified T.D.N of barely, the equivalent weight of barely, identified for each range/ha in different price scenarios (guaranteed, international and farm prices), total value of forage production calculated based on barely price. Results showed that, Forage yield equivalent to barely was estimated 276.5 kg per ha of 89826.7 usable summer rangelands. Its economic value was equivalent to 713280 Rials per hectare. Also, its average annual economic value by 3 price senarios estimated, 64.6 Milyard Rials. This amount of economic value was equal to 718900 Rials per hectare of Nour-rud rangelands. Also, the estimated forage values are only 25 percentage of total economic value of rangeland ecosystem that has been exploited as natural bequest without any investment.
amir houshang ehsani; Marzieh Foroutan
Abstract
In this study the land surface in western half of hyper-arid Lut desert, in south east of Iran, which is covered by Yardangs, a worldwide typical landform for Aeolian erosion, were classified by Self Organizing Maps (SOM) method. In the first step by using Digital Elevation Model with 10 m resolution ...
Read More
In this study the land surface in western half of hyper-arid Lut desert, in south east of Iran, which is covered by Yardangs, a worldwide typical landform for Aeolian erosion, were classified by Self Organizing Maps (SOM) method. In the first step by using Digital Elevation Model with 10 m resolution and Matlab software, 22 morphometric parameters were calculated based on derivative of the surface elevation with first, second and third orders. In the second step most affective parameters for classification and the optimum number of classes were found through utilizing Optimum Index Factor and Davies Bouldin Index. Finally SOM classification was performed on seven morphometric parameters to result in seven classes. The results showed that most appropriate parameters in classification of area are plan curvature, rotor, hypsometric Integral, total accumulation curvature, slope steepness, extreme curvature and mean curvature. The study area were divided to seven classes including saddle valley, Concave ellipsoid, Gentle slope corridor, shoulder with concave slope, shoulder with convex slope, ridge, corridor channels. Sensitivity analysis results revealed that the most sensitive parameters are rotor, mean curvature and hypsometric Integral. Also the results of Jeffreys-Matusita Distance illustrated that parameter pair hypsometric integral / extreme curvature has the most ability in separation of classes in this area. Comparison of the separated classes with the landforms on aerial photographs confirms our classification results.
mohsen hosseinkhani; akbar fakhire; alireza shahriari; ahmad pahlavanravi; soheila noori
Abstract
In this research using GIS effect of land management and soil criteria with eight indicators to study the sensitivity to the desert lands of the region of Sistan jazinak creation is evaluated. Vote based on the model parameters wilderness - the latest creation ESAs evaluation method wilderness creation ...
Read More
In this research using GIS effect of land management and soil criteria with eight indicators to study the sensitivity to the desert lands of the region of Sistan jazinak creation is evaluated. Vote based on the model parameters wilderness - the latest creation ESAs evaluation method wilderness creation and in most European countries and the Middle East is used, took place. Using the above method each of the indicators studied work unit was evaluated for each index layer was prepared by the information obtained data compiled GIS environment and desired criteria for each layer made of information was. Ultimately determine the geometric mean combining and intelligence layer criteria examined in the study area based on the model (ESAs), the intensity map obtained desert region creation. Based on the results obtained from the map 8/15 percent low fragile Brigade were part of the 20/08 percent Brigade fragile among moderate, 26/80 percent high-intensity part of the fragile type and 39/45 percent of the area Critical moderate intensity is too much Measure of the numerical value of the soil with 1/22 and the least impact with the numerical value of land management measures 1/72 greatest impact in the desert region has creation. Among the indicators two indicators, respectively, slope and soil texture with a numerical value, and 1/03 and the two lowest impact indicator pebbles and operations management, respectively, with the numerical value of 1/91 and 1/84 Desert greatest impact on morbidity region are considered.
Kh. Osati; A. Salajegheh; S. Arekhi
Abstract
Spatiality assessment of groundwater pollution is very important to determine water quality condition, pollution sources and management decisions. In this case, GIS and geostatistics methods can be useful tools. Spatiality of groundwater quality parameters, in relation with various land uses, can be ...
Read More
Spatiality assessment of groundwater pollution is very important to determine water quality condition, pollution sources and management decisions. In this case, GIS and geostatistics methods can be useful tools. Spatiality of groundwater quality parameters, in relation with various land uses, can be very extremely. Therefore water samples from 52 wells in the Kurdan area were analyzed in this study. The results show that nitrate concentrations are less than maximum acceptable concentration in drinking water (i.e. 50 mg/L as nitrate recommended by ISIRI and WHO guideline values) except to one sample (2 percent of samples) in the study area. Various geostatistics methods, e.g. IDW (power 1-4), ordinary Kriging and RBF (five Kernel functions) were compared after assessing the variograms and the spatiality of nitrate samples. Then the model parameters were calibrated and through the specific methods, predicted and standard errors maps were prepared. Errors criteria show that Kriging is the best fitting model in the study area. Finally, probability map of NO3 concentrations exceeding the threshold value of 50 mg/L, is generated using the Indictor Kriging method. Spatiality of NO3 show that Nitrate concentration is increased where the rock type is permeable, land use is agriculture and slope is enough low to infiltrate polluted water into the wells. This research also tries to describe how to assess the spatiality of groundwater parameters by GIS.
Hamid Toranjzar; Asghar Zare Chahouki
Abstract
Geostatistical approaches have great importance because they include spatial correlation of geographic data. Present study evaluated the efficiency of geostatistical techniques and demonstrated their capabilities in studying the soil variables(soil texture (sand percent), EC and So4-2) in the important ...
Read More
Geostatistical approaches have great importance because they include spatial correlation of geographic data. Present study evaluated the efficiency of geostatistical techniques and demonstrated their capabilities in studying the soil variables(soil texture (sand percent), EC and So4-2) in the important plant community of Nitraria schoberi in Meighan desert, Arak. A regular grid on the map comprising rectangular cells was designed and situated over the experimental area with 98 points for vegetation type. The grid was laid out in the field using the global positioning system. Soil samples were taken between 0-20 and 20-100 cm layers for each point. Analysis using the best view at semivariogram model were applied to select the Gaussian models of soil characteristics with R2 higher than 0.95. Among ordinary Kriging, simple Kriging and Inverse distance weighting methods, ordinary kriging method showed the best cross-validation criteria (mean square error and average error) and had higher prediction accuracy than others. Finally, spatial estimates of the soil characteristics were performed using ordinary kriging.
leila khalasiahwazi; Mohammad Ali Zare Chahouki
Abstract
Zygophyllum atriplicoides is one of the most important rangeland plants that often seen as associated species and rarely seen as the dominant species in ranglands rangelands which is very critical for soil in starting and ending points of each transect. Measured soil properties (included gravel, ...
Read More
Zygophyllum atriplicoides is one of the most important rangeland plants that often seen as associated species and rarely seen as the dominant species in ranglands rangelands which is very critical for soil in starting and ending points of each transect. Measured soil properties (included gravel, texture, organic matter, lime, pH and electrical conductivity) and physiography (elevation and slope) is measured also. By importing the information layers in appropriate model and using necessary statistical analysis in ENFA model, the map of its potential habitat has been created. The results showed that 25200 hectares of study site is potential habitat of Zygophyllum atriplicoides which is 34 percent of study site. To evaluate the verity of this model, Boyce index has been used and model rectitude in this test was determined as 87.2 percent. The result of this model is shown that PH and Lime are the main effective factor to determine potential suitable of this plant species.
Moslem Borji Hassan Gavyar; Hadi Eskandari Dameneh; Hassan Khosravi
Abstract
Nowadays, temperature increase, rainfall decrease and its effect on the time dynamics of carbon fixation cycle still are faced by many uncertainties. Net Primary Production (NPP) is one of the main factors of carbon cycle; precipitation and temperature measurement are known as two useful tools to study ...
Read More
Nowadays, temperature increase, rainfall decrease and its effect on the time dynamics of carbon fixation cycle still are faced by many uncertainties. Net Primary Production (NPP) is one of the main factors of carbon cycle; precipitation and temperature measurement are known as two useful tools to study different ecosystems stability and resilience in terms of climate. Hence, in this study, NPP distribution affected by climate parameters of temperature and precipitation have been investigated in four ecosystems of forests, grassland, irrigated agriculture and rain fed agriculture during the period of 2003-2010. Considering climate conditions of biomes, NPP estimation at regional scale was done based on the NASA Moderate Resolution Imaging Spectroradiometer (MODIS) MOD17 NPP product. The results showed that the regression relation was weak between NPP and rainfall for four studied ecosystems, in the other words, low coefficient between these two variables has caused no justified relationship between them. The regression relation between temperature and NPP in forests, pastures and rain-fed agriculture ecosystems follows quadratic equations with determined coefficient over 0.55. The results of this study show that the forest ecosystem resilience to water and temperature tensions is more than other ecosystems, and irrigated agriculture has the least resilience
alireza estelaji; ahmad hajalizadeh; masoud heydarvand
Abstract
Community-based management is a process of management involving local beneficiaries actively in all stages of planning and implementing management programs so that each are at the center of decision-making. Since community-based management contributes greatly to the improvement of bridging social capital, ...
Read More
Community-based management is a process of management involving local beneficiaries actively in all stages of planning and implementing management programs so that each are at the center of decision-making. Since community-based management contributes greatly to the improvement of bridging social capital, present study analyzes the effectiveness of co-management for strengthening social capital. The research population consisted of heads of four villages i.e. Ziyaratshah, Deh Reza, Aostam Ababd-e-Alicharak, and Ali Abad Hashtsad Metri, Rigan County, Kerman province. Since community-based management of arid areas was implemented in this region, it was chosen as pilot. Social capital assessment through network analysis and measurement of trust and collaboration ties applying macro level indicators (whole-network) of local beneficiaries’ network was done. Network analysis questionnaire was applied for data gathering and 33 participants were chosen through whole network sampling method and they were interviewed. It was found out that indicators were at medium level prior to project implementation but they showed positive and incremental trend following the implementation of community-based management. Therefore, this project led to trust building and improved cooperation improved among heads and as a result, bridging social capital enhanced.
Mohammad Bashirgonbad; Alireza Moghaddam Nia; Shahram Khalighi Sigaroodi; Mohammad Mahdavi; Emmanuel Paquet; Michel Lang
Abstract
There are many methods for estimating the maximum flood discharge including frequency analysis methods and risk study of hydraulic structures based on flood frequency analysis is often sensitive to the observations and selected statistical distribution that cause errors in design. Since heavy rainfalls ...
Read More
There are many methods for estimating the maximum flood discharge including frequency analysis methods and risk study of hydraulic structures based on flood frequency analysis is often sensitive to the observations and selected statistical distribution that cause errors in design. Since heavy rainfalls are the main cause of floods and the rainfall records are longer than flow records, hence long-term records of rainfall at rain gauge stations of Bakhtiary basin in a 66-year period and the 58-year records of daily maximum discharge were used in this study. In this research, peak and maximum daily flows were estimated by using hydro-climatic methods of Agregee and Gradex. Then, the results obtained from the simulation based on hydro-climatic approach for the different return periods were compared with those of classical statistical techniques of Gumbel and Generalized Extreme Values (GEV). The results showed that using additional information like rainfall data plus hydrometric data in hydro-climatic methods gives better estimates rather than frequency analysis methods. Because each three evaluation criteria of Root Mean Squared Error (RMSE), Nash–Sutcliffe efficiency (NSE) coefficient, Kling-Gupta efficiency (KGE) coefficient confirm performance of hydro-climatic methods in comparison with Gumbel and Generalized Extreme Values (GEV) distributions. Finally, a peak to volume ratio extracted from the 26 major flood events detected at Tang-e panj hydrometric station within the hourly discharge records was used to transform the cumulative distribution function of daily discharge into peak discharge.
Alireza Eftekhari; Mohamad Jafari; Hossein Arzani; Aliakbar Mehrabi; Mohammad Reza Bihamta; Ehsan Zandi Esfahan; Nadia Kamali
Abstract
Given the role of rangelands in soil conservation and soil fertility, strengthening the soil of rangelands could be achieved by range management plans (RMP). Therefore, in this research, 15 summer rangelands and 16 winter rangelands with RMP were investigated to determine the effects of range management ...
Read More
Given the role of rangelands in soil conservation and soil fertility, strengthening the soil of rangelands could be achieved by range management plans (RMP). Therefore, in this research, 15 summer rangelands and 16 winter rangelands with RMP were investigated to determine the effects of range management plans on some soil properties. In each rangeland with RMP and in each vegetation type, three soil profiles were dug and soil samples were collected at two different depths. Beside each rangeland with a RMP, a rangeland with a same vegetation type and without RMP was selected for comparison and sampling was conducted. Organic matter, nitrogen, potassium, and phosphorus were measured in the laboratory. The data from two different range management types were analyzed in an independent sample T test using SPSS software. The results showed that, in summer rangelands, range management plans could increase the amount of some factors like phosphorus, nitrogen, and organic matter, while it had no significant impact on some other factors, including the amount of potassium and increasing the depth of horizon A. However, in the winter rangelands, the plans had no significant effect on strengthening the soil of rangelands and it seems that due to the slow changes of soil in arid areas, more time is needed to make significant changes in the soil.
Reyhaneh Masoudi; Gholamreza Zehtabian; Hassan Ahmadi; Shahram Khalighi sigarudi
Abstract
Desertification is a major problem in many countries. International efforts have been considered to combat and prevent this phenomenon. The most important cases of these measures are the United Nations Convention to Combat Desertification. In this study, IMDPA model and GIS were used to assess desertification ...
Read More
Desertification is a major problem in many countries. International efforts have been considered to combat and prevent this phenomenon. The most important cases of these measures are the United Nations Convention to Combat Desertification. In this study, IMDPA model and GIS were used to assess desertification phenomena in Kashan Plain. Some indices of Climate and water criteria were selected to consider for each condition of the region. Final desertification intensity was calculated based on geometric average of the selected criteria and their indices. The numerical value was classified in 5 classes including non-significant, low, medium, severe and very severe and desertification intensity map was drawn using GIS in the studied period. According to the results, among the studied indices, the groundwater level depletion, EC and Transu aridity index with 3/82, 3/04 and 3/01 numerical values are the most effective factors. The threshold of ground water level, EC and Transu aridity index were determined respectively: more than50 cm/year, 2250-5000((μmohs)⁄(cm)) and 0/05-0/2. Also, the case study has classified in medium class of desertification with DS=2/4. Regarding the determined thresholds were specified the sensitive areas, and the required equipment are proposed to install on these areas for observing the thresholds.
Hossein Piry; Mohammad Ali Zare Chahouki; Hossein Azarnivand
Elnaz Hassanzadeh Kuhsareh; ardavan ghorbani; Mehdi Moameri; kazem hashemi majd; Ardeshir pounemati
Abstract
The purpose of this study was to determine the effects of altitude, slope, aspect and topographic index on life forms and total net primary production (NPP) in mountains meadows in Fandoghlou in Namin county in Ardabil province. NPP in three altitude, slope, topographic index classes and four aspect ...
Read More
The purpose of this study was to determine the effects of altitude, slope, aspect and topographic index on life forms and total net primary production (NPP) in mountains meadows in Fandoghlou in Namin county in Ardabil province. NPP in three altitude, slope, topographic index classes and four aspect classes was estimated using one m2 plots (totally 180 plots) by harvesting and weighting method. Correlation between life forms and total NPP with topographic factors were analyzed using stepwise multivariate regression method and using derived regression equations, the maps of NPP were derived. Results show that different topographic factors has significant effects on forbs (p<0.01) and grasses (p<0.01), however on total NPP have no significant effects. The highest NPP of forbs (1584/1 Kg/ha) and total NPP (2339/3 Kg/ha) were observed in the second altitude (1525-1564 m) but has no significant effect on grasses. The NPP of grasses show direct relationship with slope, however the NPP of forbs were decreased with the increase of slope and has no significant effect on total NPP. The highest amount of grasses (894/3 kg/ha) and forbs (1875/5 Kg/ha) were observed in the south and northwest aspect, respectively. According to the various classes of topographic index, the maximum amount of grasses (853/4 Kg/ha) were observed in the first classes and the highest NPP of forbs (1568/6 Kg/ha) on the third classes. The results of this study can be used to balance the amount of biomass, carbon, the supply and demand of and to plan for proper rangeland management.
Seyyed Erfan Khamoshi; Fereydoon Sarmadian; Ali Keshavarzi
Abstract
Soil is known as a dynamic media so it easily degrade with inapplicable usage so with increasing in degradation of this limited source, the world’s food safety would be in danger. Thus, applicable and sustainable usage of agricultural lands are become an essential and inevitable agenda. Therefore, ...
Read More
Soil is known as a dynamic media so it easily degrade with inapplicable usage so with increasing in degradation of this limited source, the world’s food safety would be in danger. Thus, applicable and sustainable usage of agricultural lands are become an essential and inevitable agenda. Therefore, the aim of this study is to Digital soil mapping using decision tree for agricultural land suitability, In order to constitute management programs for sustainable use of agricultural lands. For this aim, samples were collected based on cLHS and after some laboratory experiments, modeling and digital soil mapping were created by Random Forest Model. Also, agricultural land suitability for dominant crops were investigated by parametric method. The results showed that the land evaluation for irrigated wheat with surface irrigation 75.27% of the total area S2 class and 24.73% of the land in the class S3, respectively. In assessing the suitability of land for Maize irrigation, 14.78% of the land in classes S1, S2 84.82 of class and 0.39% of the land in the class S3, respectively. Results for alfalfa irrigation land evaluation showed that 11.10 percent of the land in classes S1, 88.49% in the S2 class and 0.4% of the class S3, respectively
Hamid Jamali; Ataollah Ebrahimi; Elham Ghesareh Ardestani; Fatemeh Pordel
Abstract
Density is an important indicator of vegetation evaluation, which several methods have been developed for its assessment, but their accuracy is concerned. To reveal accuracy of each methods, a study site of 32000-m2 in the steppe rangeland of Marjan, Boroujen was selected and divided into eight macroplots ...
Read More
Density is an important indicator of vegetation evaluation, which several methods have been developed for its assessment, but their accuracy is concerned. To reveal accuracy of each methods, a study site of 32000-m2 in the steppe rangeland of Marjan, Boroujen was selected and divided into eight macroplots of 4000-m2. Then, the individuals of Astragalus verus and Astragalus albispinus were counted in each microplots. A transects of 100-m established parallel to the length of the macroplots (40 × 100 mm) and density was measured using closest individual, nearest neighbor, random pairs, point-centered quarter, third closest individual, angle order and variable area transect methods, systematic-randomly in 10 sampling points in each macroplots. The results indicate that the real density of A. verus and A. albispinus were 0.1593±0.084 and 0.0622±0.0282/m2, respectively. Closest individual (0.1357±0.1315/m2), nearest neighbor (0.1368±0.1432/m2), point-centered quarter (0.1016±0.1664/m2), random pairs (0.0588±0.0536/m2), third closest individual (0.1107±0.0775/m2) and variable area transect (0.0221±0.0105/m2) for A. verus and angle order (0.0927±0.0523/m2), nearest neighbor (0.0424±0.0357/m2) and third closest individual (0.0524±0.0447/m2) for A. albispinus showed no significant difference with controls. The results revealed that the closest estimation to the controls belongs to the nearest neighbor (-0.141) and third closest individual (-0.0098) for A. verus and A. albispinus, respectively. Moreover, the nearest neighbor (RMSE=0.6877, SE=0.0026 and R=0.1147) and closest individual (RMSE=0.5609, SE=0.0007, R=0.0320) showed the most precise estimation of densities of A. verus and A. albispinus, respectively. Generally, the closest individual for estimating plant density of A. verus and the nearest neighbor's for A. albispinus are proposed.
H. Khedri Gharibvand; Gh. A. Dianati Tilaki; M. Mesdaghi; M. Sardari
Volume 62, Issue 1 , June 2009
Abstract
The aim of this research was to determine the effects of Camphorosma monspeliaca species on soil nutrient elements in its habitat. For rangeland, ecological positive or negative effects of plant species on environment must carefully be examined before allowing their plantation in vast areas; on the other ...
Read More
The aim of this research was to determine the effects of Camphorosma monspeliaca species on soil nutrient elements in its habitat. For rangeland, ecological positive or negative effects of plant species on environment must carefully be examined before allowing their plantation in vast areas; on the other hand this species with their special characteristics have special effects on their surrounding environment that should be considered. Camphorosma monspeliaca is one of non-native and adapted species in Chaharmahal and Bakhtiari province that its habitat has 3500 ha area. Effect of this species on environment requires more studies on their different aspects. Here we studied effect of this species on soil in order to assess its ecological effects on environment. This species distributed in all of the landscape but most distribution of species located at southern and northern aspects and in areas with flat topography. Companion species in topography position are different. This species can establish in non saline soil. The research was carried out at three stages of field sampling, soil test and statistical analysis. The research method was based on comparison between adjacent stand and stands of this species. Soil variables in two depth 0-10 cm and 10-30 cm were measured. Result showed that in two depths, were not significant difference but, in case of soil mineral elements, plant stands have significant difference; effect of depth and plant stands was not significant. There was significant difference adjacent stand and stands of this species in terms of Na, Mg, OC and in stands of this species were greater than the adjacent stands. This species increased content of carbon organic¬ and Na, Mg. From the results obtained on three topographic position, despite of negative effect of Camphorosma monspeliaca on sub soil with increase of Na and Mg, it can be concluded that Camphorosma monspeliaca had a positive effect on soil organic¬ matter. In general this plant has a good perspective and further studies about different aspects of this species are necessary.
Farhad Lashgarara; Majidreza Davarpanah; S.Akbar Javadi
Abstract
This study Proceeded the Identity of the shackles of Participation pasture manageres about Performance Projects range- Management to Central Part kohkiloie Township. The purpose in this study was to Identity of the shackles of Participation pasture manageres about Performance Projects range- Management ...
Read More
This study Proceeded the Identity of the shackles of Participation pasture manageres about Performance Projects range- Management to Central Part kohkiloie Township. The purpose in this study was to Identity of the shackles of Participation pasture manageres about Performance Projects range- Management to Central Part kohkiloie Township. The present research is applied research by using descriptive and correlational methods and its instrument was questionnaire. The present statistical community consisted of 197 numbers of the pasture manageres which based on the ''Cochran'' formula, by using of Random Sampling, the number of 110 were selected as the statistical sample.Data was analyzed by using SPSS win software. Findings Through Spearman Rnank Correlation Coefficient, Pearson's Correlation Coefficient and Eta Correlation Coefficient has shown that based on the pasture manageres' views, the Personal Factors, the Social Factors, Economical Factors, Political Factors and Didactic Factors wouldeffect on the shackles of Participation pasture manageres about Performance Projects range- Management, while the variable of Age, Precedence, Size Land, Literacy and Sexuality don't effect on the shackles of Participation pasture manageres about Performance Projects range- Management. The result from stepwise regression analysis showed that, the Social Factors and Didactic Factors had positive effects on shackles of Participation pasture manageres about Performance Projects range- Management.
Esfandiar Jahantab; Ali Najmeddin
Abstract
Heavy metal pollution is one of the most serious environmental problems that is spreading around the world. The purpose of this study was to determine the rate of pollution and enrichment of heavy metals inside and around the industrial town of Shiraz. For this aim, 20 surface soil samples were gathered ...
Read More
Heavy metal pollution is one of the most serious environmental problems that is spreading around the world. The purpose of this study was to determine the rate of pollution and enrichment of heavy metals inside and around the industrial town of Shiraz. For this aim, 20 surface soil samples were gathered from a depth of 0 to 15 cm from inside and around Shiraz industrial town, and the concentrations of Pb, Cr, Al, Mn, Cu, Zn, St, V, N, Co, Sc, Fe As was evaluated using the ICP-method MS. The results showed that the average concentrations of Cu, Pb, Mn, Cr, Al, Zn, St, V, Ni, Co, Fe, As and Sc are 75, 87.9, 541.6, 143.3, 21804.8, 275.4, 439.9, 173.3, 55.4, 12.0, 50579.3, 4.8, and 4.7 mg / kg, respectively. The results showed that the average concentration of all elements except Al (21804.8 mg/kg) and Sc (4.7 mg/kg) is much higher than the concentration of these elements in global soils. In addition, Cu, Pb, Zn, V and Cr show much higher concentrations than standard Chinese and Canadian standards. Calculation of the enrichment coefficient of the mentioned elements in soil samples indicates high enrichment of Cu (8.32), Pb (5.42), Zn (7.04), St (5.15), V (5.04), and Cr (5.34). The results of the present study indicate that the soils of the region are contaminated with Cu, Pb, V, Mn and Zn. Therefore, it is suggested to reduce metals in the environment by different methods.
zohreh khorsandi; Mohammad Mahdavi; Ali Salajeghe; Saeid Eslamian
Abstract
Quantification of urban hydrologic response of catchments to rain fall is one of the most importantissues in urban hydrology. Despite its importance, there is scant information by means of whichrequired data can be obtained for quantifying hydrologic response. In this study, urban database wasdeveloped ...
Read More
Quantification of urban hydrologic response of catchments to rain fall is one of the most importantissues in urban hydrology. Despite its importance, there is scant information by means of whichrequired data can be obtained for quantifying hydrologic response. In this study, urban database wasdeveloped for a part of Baharestan City in Isfahan Province and using the information, the urbanunit hydrograph was determined through URBS-UH model for two catchments of Baharestan. Peakof hydrograph of the first and second catchment was estimated 0.0727m3/s and 0.096, respectively.Flood hydrograph of some rain occurred previously in Baharestan was determined through the unithydrograph. Peak discharge of flood was also measured and the efficiency of the developed modelwas examined based on the peak information. Nash–Sutcliffe coefficient of the first and the secondcatchment were estimated 0.89 and 0.79, respectively. The developed model showed good to verygood performance in the pilot area.
S.M Soleimanpour; majid Soufi; hassan Ahmadi
Volume 63, Issue 1 , June 2010, , Pages 41-52
Abstract
Gully erosion has an important role in Fars province due to sediment production and enormous damages to land, roads and infrastructures. In this research, 15 gullies were selected to measure their morphometric characteristics. The length, depth, top and bottom width and volume of gully erosion were then ...
Read More
Gully erosion has an important role in Fars province due to sediment production and enormous damages to land, roads and infrastructures. In this research, 15 gullies were selected to measure their morphometric characteristics. The length, depth, top and bottom width and volume of gully erosion were then measured. Influential factors on the sediment production and gully development were analyzed and determined by using stepwise method in SPSS software. The results indicate that sediment production due to gully development is related to three variables including drainage area, silt and the sand percent of the watershed above the gully heads. These results imply that surface runoff is acting as dominant hydrologic process on gully development. Investigation on the topographic threshold reveals that drainage area exponent (b) is negative and these results are in the same line with the results of some recent relevant studies. The results also indicate the watershed characteristics and geological formation impact on the gully sediment production. Gully development could be reduced by decreasing the area of bare land as the main source of surface runoff by vegetation planting and terracing. Constructing of small earth dams at the end of gullies collect surface runoff and provides better situations for vegetation establishment around gullies.
