Papers by Environmental Resources Research
Environmental Resources Research, 2021
Soil is an essential natural resource for life that provides the required substrate on which plan... more Soil is an essential natural resource for life that provides the required substrate on which plants grow and flourish. One of the challenges for environmental specialists is to accurately estimate and control soil erosion. MPSIAC (Modified model of Pacific Southwest Inter-Agency Committee) is a common model for estimating erosion and sedimentation rate. In this study, we used MPSIAC, regression and artificial neural networks (ANN) to estimate sediment yield in Kordan Basin, a region in Alborz Province of Iran. The erosion and sedimentation data of the region were collated using the opinions of sedimentation experts. A linear regression was performed in Weka software to determine the factors influencing the sedimentation rate. Based on the results and the opinion of the experts, the factors with less impact on the sedimentation were removed. ANN was implemented using NeuroSolutions and Matlab software. The neural network was a Multi-Layer Perceptron (MLP) with one hidden layer and five neurons. The hidden layer consisted of tan-sigmoid activation function, and the output layer had a linear-sigmoid activation function. The algorithm used for training the neural network was Levenberg-Marquardt. The ANN results were superior to that of regression and the Matlab's output was more accurate than that of NeuroSolutions, with a mean square error of 0.009 for sediment yield. Finally, Matlab's neural network was extracted in the form of a function for later applications without the need to further training.
Environmental Resources Research, 2021
Astragalus podolobus is a thorn less half-shrub plant that is considered as one of the most valua... more Astragalus podolobus is a thorn less half-shrub plant that is considered as one of the most valuable species in the Iran rangelands. Land-use changes and rangelands degradation represent a real threat to it. To determine how to manage it better, the potential spatial distribution of this species was mapped using a bivariate statistical model (FR: frequency ratio) for the Maraveh Tapeh rangelands of Golestan province, north-east Iran. A total of 115 occurrences of A. podolobus were recorded using GPS during field surveys from April to September in 2018 and 2019, then 80 data points (70%) were modeled, and 35 data points (30%) were used to evaluate the model. In the form of digital layers, 8 variables potentially affecting the habitat suitability of the plant were selected as independent variables, including; distance from road and river, elevation, plan curvature, precipitation, slope percentage slope aspect and temperature. The results of the relationship between the effective variables and the presence of the plant species showed that the variables of temperature, precipitation, and distance from the road have a greater effect on the presence of the A. podolobus. . The newly derived habitat suitability map produced using the FR model is a powerful tool harnessed for the development of conservation projects of the degraded habitat of A. podolobus. The analytical framework used in this study could be applied to other arid and semi-arid environments to determine suitability habitat of A. podolobus and stabilize this species, also to introduce new adaptive rules for rangeland management.
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Environmental Resources Research , 2021
Rangelands are one of the most important terrestrial ecosystems that are very important in the ca... more Rangelands are one of the most important terrestrial ecosystems that are very important in the carbon sequestration process. In this study, the amount of carbon pool was measured and compared in the habitats of Haloxylon ammodendron and Calligonum comosum in Mirjaveh plain, Sistan and Baluchestan province (in 2021). The research was based on a completely randomized design. Above and belowground biomass was harvested along 100 m transects. In order to determine the soil carbon pool of plant species, sampling was performed from three depths )0-15, 15-30 and 30-45 cm (. The amount of soil and plant organic carbon, bulk density and carbon storage of plant and soil were measured. Data were analyzed using SPPSS.20. The results showed that in both habitats, the highest and lowest amounts of organic carbon and soil carbon pool were related to depths of 0-15 and 15-30 cm, respectively. Results showed that in both habitats, soil carbon pool, bulk density, organic carbon had the maximum levels in the 0-15 cm soil layer. In C. comosum habitat, Cp in the 0-15 cm depth was more than the same soil depth in H. ammodendron habitat. In both plants, Cp in the belowground biomass was significantly more than the aboveground biomass (p<0.01). In particular, our study showed that C. comosum has more potential to store carbon compared with H. ammodendron. The use of shrubs in biological practices can increase the carbon pool in arid lands but, the efficiency of more plant species needs to be assessed.
Environmental Resources Research , 2021
Water is the most critical natural resource in the world and one of the scarce inputs of the agri... more Water is the most critical natural resource in the world and one of the scarce inputs of the agriculture sector in arid and semi-arid areas, including Iran. Consecutive droughts, lower groundwater levels, and lower water quality are among the concerns of farmers and policymakers in Iran. Therefore, the impacts of various factors, including the knowledge-based economy index on the water crisis in Iran were investigated. We applied the Bayesian Network for modeling water crisis management. In doing so, we identified the key factors related to water crisis management using the U.N. indicators. The composite index of the knowledge-based economy was calculated using knowledge assessment methodology. The results of the U.N. indicator indicated that Iran is in a state of severe water crisis. The modeling results showed that advances in the knowledge-based economy index could alleviate the water crisis. Also, we found that increased economic growth could exacerbate the water crisis. Sensitivity analysis showed that drought has the most significant impact on the water crisis. Therefore, planning and policymaking to advance the various components of the knowledge-based economy and moving towards sustainable development can help manage the water crisis. The components of the knowledge-based economy comprised innovation, knowledge and human resources, information and communication infrastructures, and economic incentives and institutional regimes.
Environmental Resources Research , 2021
The Lonsdorf model simply considers the potential of land covers in providing nesting habitat and... more The Lonsdorf model simply considers the potential of land covers in providing nesting habitat and floral resources for mapping pollination services in different landscapes. However, this model does not take into account topographic and climatic factors in its modeling and does not include edge effects of factors such as roads, rivers, lakes, and wetlands, which affect the presence of pollinators. To overcome these problems, we used the ESTIMAP model to improve the results of the Lonsdorf model. For this, we included the effects of roads, railways, rivers, wetlands, lakes, altitude, climate, and ecosystem boundaries in the ESTIMAP modeling and compared the results with the Lonsdorf model. The results of the Lonsdorf model showed that the majority of Iran had a very low potential for providing pollination service and only three percent of the northern and western parts of Iran had high potential. However, the results of the ESTIMAP model showed that 16% of Iran had a high potential to provide pollination that covers most of the northern and southern parts of the country. The results of the ESTIMAP model for pollination mapping in Iran showed the Lonsdorf model of estimating pollination service can be improved through considering other relevant factors.
Environmental Resources Research , 2021
Aquatic ecosystems contaminated by heavy metals are a worldwide concern. These metals are toxic a... more Aquatic ecosystems contaminated by heavy metals are a worldwide concern. These metals are toxic and persistent. This research aimed to measure mercury in the hair of fishermen, working at Chahnimeh Reservoirs, Sistan and Baluchistan Province, southeast of Iran. Samples were collected from April 2012 to October 2012 from 40 local fishermen. Those fishermen with amalgam-filled teeth (a source of mercury) were excluded. The average amount of mercury in the samples was 1.56 μg/g (ranging from 0.1 to 3.65 μg/g). In 29 fishermen (72%) hair mercury levels exceeded the reference dose of the USEPA. The results in this study showed that height and age were not significantly related to mercury levels, but body weight and BMI were. Fish consumption (p=0.001), smoking (p=0.018), weight (r=0.35, p=0.02) and BMI (r = 0.35, p=0.02) were significantly related to hair mercury levels. Fruit (p=0.017) and dairy consumption (p<0.001) were inversely related to the concentration of mercury in hair.
Environmental Resources Research , 2021
River flow forecasting is of immense importance for reliable planning, designing, and management ... more River flow forecasting is of immense importance for reliable planning, designing, and management of water resources projects. This study investigated the performance of wavelet neural network, support vector machine, artificial neural network, and Multiple Models Driven by Artificial Neural Networks (MMANN) in predicting flow time series of the Kashkan River in Lorestan, Iran. Daily flow time series was created from the records of Kashkan hydrometric and rain gauge stations for a 10-year period from 2006 to 2016. To determine the best input-output mapping, estimations were repeated with different combinations of inputs derived from previous daily river flow data. Performance of the models was evaluated in terms of correlation coefficient, root mean square error, and mean absolute error. Performance comparisons showed that the MMANN model with a correlation coefficient of 0.960, root mean square error of 0.021, and mean absolute error of 0.001 generates the best daily flow estimates for the studied river.
Environmental Resources Research , 2021
The plant growth-promoting rhizobacteria (PGPR) are one of the famous sources when applying droug... more The plant growth-promoting rhizobacteria (PGPR) are one of the famous sources when applying drought stress management in rangeland plants. This research was conducted to investigate the effect of PGPRs on the germination and growth of Astragalus cyclophyllon Beck under drought stress. A factorial experiment in a completely randomized design with three replications, was conducted in the seed laboratory. The effects of the main factors of PGPR inoculation as well as control and drought stress at four levels and their interactions on weight, length, and germination indices were investigated. Bacillus cereus had the highest effect on increasing shoot, seedling dry weight, and vigour indices. Pseudomonas aeruginosa had the highest effect on promoting radicle length. Additionally, results revealed that -0.8 MPa drought stress had a significant effect on radicle and shoot fresh weight, shoot and seedling length, germination percentage, germination rate and mean daily germination as compared to 0.0, -0.2 and -0.4 MPa indicating A. cyclophyllon is a drought stress resistance species. B. cereus at the control level of drought stress significantly increased shoot and seedling dry weight and vigour indices, whilst, P. aeruginosa at the drought stress level of -0.8 MPa significantly increased shoot lengths compared to control. In general, B. cereus significantly increased biomass by increasing shoot and seedling dry weight but P. aeruginosa affected elongation growth of the plant by increasing radicle and shoot lengths of A. cyclophyllon. Suitable PGPR as biotic elicitors can enhance the growth of the rangeland plants.
Environmental Resources Research, 2021
Many of the serious today's environmental problems are, directly or indirectly, caused by humans'... more Many of the serious today's environmental problems are, directly or indirectly, caused by humans' irresponsible behavior. The current study, then, aimed at modeling the environmental behavior of tourists in destinations found in Birjand, Iran. The effects of independent constructs such as environmental perception (P), satisfaction (S), attitude (A), and active involvement (AI) on the dependent construct of the environmental behavior (EB) of tourists were investigated. The Partial Least Squares Structural Equation Modeling (PLS-SEM) was used via SmartPLS 3 software. According to the results, the reliability of the model, and Cronbach's alpha values of latent and observant variables were acceptable (EB=0.851, P= 0.898, S=0.920, A=0.852, AI= 0.903); the combined reliability (rho or CR) for constructs ranged between 0.874 and 0.931. The average variance extracted (AVE) for EB, P, S, A, and AI were measured at 0.385, 0.555, 0.530, 0.530, and 0.595, respectively. The correlation between latent variables, according to Fornell and Larker method showed that the A and AI constructs were more positively correlated with each other. As a whole, the results showed that perception has a significant and positive effect on the tourists' environmental behavior in natural and historical destinations. This is while no significant correlation was found between satisfaction, attitude, and active involvement. This research provided a scientific basis for tourism management and offered some suggestions that can be useful for formulating policies, and wise tourism development in the context of environmental protection in relevant administrative departments.
Environmental Resources Research, 2021
In this study, spatio-temporal forest canopy cover density changes in the Golestan National Park ... more In this study, spatio-temporal forest canopy cover density changes in the Golestan National Park (Iran) were assessed from 1967 to 2016 using aerial photos and satellite images in a Geographical Information Systems environment. The digital aerial orthophoto mosaics were created after georeferencing photos of the years 1967 and 1994. A special canopy interpretation key was used for interpreting and determining the forest canopy cover classes on the digital orthophoto mosaics and Google earth images and for providing the canopy cover density maps. The results indicated that throughout the period from 1967 to 1994, the non-forest areas in some places were converted into forest due to physical and technical management measures. Results also showed that between 1967 and 2016, the canopy cover class 10-25% had the highest increase (16.6%) followed by the 25-50% class that increased by 21.17%. Our research exhibited that applying the physical preservation and protection management plans are the major factors in conversion of non-forest to forest areas and increase of the canopy cover density. These results emphasize that active physical protection and proper implementation of management methods are required for forest restoration in the study area.
Environmental Resources Research , 2021
Environmental pollution is nowadays one of the main challenges of the world. The global economic ... more Environmental pollution is nowadays one of the main challenges of the world. The global economic growth and the associated environmental degradation have put environmental protection at the forefront of attention. Regarding the aim of economic growth and its impact on environmental quality, the effect of various economic and human factors on environmental pollution and degradation is increasingly gaining importance in Iran. This study investigated the effects of economic growth, energy consumption, trade liberalization, urbanization, financial development, and human development on ecological footprint and environmental degradation in Iran over the period 1971-2015 using the Markov switching-error correction method (MS-ECM). Based on the results, the environmental Kuznets hypothesis was confirmed for the ecological carbon footprint with a reversed-U shape. Economic growth, urbanization, and energy use were found to have a positive and significant effect on environmental degradation, while financial development negatively influenced environmental degradation. Also, human development had a positive effect on the ecological carbon footprint. Finally, it is recommended to save energy, especially fossil fuels, by using clean energy, increase environmental awareness, and enforce strict environmental monitoring.
Environmental Resources Research , 2021
Erosive soil processes in arid ecosystems render local heterogeneities and associated ecological ... more Erosive soil processes in arid ecosystems render local heterogeneities and associated ecological and hydrological diversities within the landscape. Spatial heterogeneity exhibits simultaneous opposing degrading and developing conditions with varying degrees of resilience. While it would have been expected that heterogeneity-induced response diversity should increase the ecosystem resilience, highly heterogeneous ecosystems promote irreversible shifts. The major question is whether heterogeneity accelerates dryland degradation or provides an opportunity for increasing sustainability. To understand this paradox, recent studies were reviewed to answer (1) the causes of spatial heterogeneity in patterns of soil biotic-abiotic properties; (2) how heterogeneity simultaneously exhibits seemingly opposite effects in dryland dynamics through the emergence of resilience thresholds. Until heterogeneity can retain multiple resilience thresholds, it will have facilitative effects on resilience of the landscape. When the distance between fragments exceeds a dispersal threshold, the disappearance of resilience thresholds promotes destructive effects of the heterogeneity, stimulating irreversible transitions. It is hoped that this review, in emphasizing the importance of the relationship between erosive soil disturbances and soil biotic-abiotic variables in the dynamics of spatial heterogeneity can provide an effective basis to quantify critical heterogeneity thresholds as an early warning sign for anticipating the future evolution trend of landscape.
Environmental Resources Research , 2021
The impact of regional plans on water resources and has always been a concern for researchers. In... more The impact of regional plans on water resources and has always been a concern for researchers. In the meantime, one of the issues which is being raised by drought is how to assess the quality of regional plans considering the drought. In this research, Fu and Tang plan assessment method called "Awareness-Analysis-Action" is used to assess the quality of six regional plans of Chaharmahal and Bakhtiari Province in Iran. Findings show that the awareness component in all plans is at an average level. Regarding the analysis component, comprehensive regional plans are in a good level, and other plans were at an average level. The action component was rated moderate in all plans and the scores related to the component of action in the plans were not different significantly. In terms of the overall plan score, only one plan received a score above average. Results of ANOVA test showed that the mean of the “Analysis component” in the plans is more than the two other components and there is no significant difference between the score of the three components of the plans. In other words, regional development plans have failed to succeed in three components of awareness, analysis, and action regarding drought adaptation.
Environmental Resources Research , 2021
The continuous growth in civilization and population have led to upsurge in generation of constru... more The continuous growth in civilization and population have led to upsurge in generation of construction and demolition (C&D) wastes. A considerable part of C&D wastes is gypsum wastes that together with its derivatives are classified as a group of binding agents in soil stabilization and immobilization and upgrading soil durability. In this study, the possibility of using gypseous wastes as a binding agent was investigated. Moreover, soil stabilized with recycled gypsum was tested under different dry-wet cycles as well as multiple dry-rewetting to assess the stability of improved soil. Different amounts of gaseous waste (0, 5, 10, and 20%) and 5% cement and 5% lime were added to clay soil at various curing conditions (0, 7, 14, and 21 days). Then, durability of samples was tested by wetting/drying cycles (0, 1, 2, and 3 cycles). Soil characteristics including compaction, unconfined compression strength, Atterberg limits and soil durability were assessed for all samples. Results demonstrated significant increase of the unconfined compressive strength in clay by addition of gypsum waste, cement, and lime. However, we detected a significant reduction in the unconfined compressive strength of the samples in the third cycle of wetting-drying test.
Environmental Resources Research, 2021
Land subsidence including downward subsidence with a horizontal displacement vector normally occu... more Land subsidence including downward subsidence with a horizontal displacement vector normally occurs in small amounts. In the present study, two pairs of Sentinel-1A descending and ascending images of 2014 and 2015 were used to survey the subsidence rate in Garmsar Plain. After ensuring the high correlation of the images, their interferogram was prepared and following removal of unnecessary phases, the displacement phase was calculated and converted to the vertical component. The InSAR analysis revealed that the Garmsar Plain witnesses an annual subsidence of 36 cm, which is very close to that of Tehran and Varamin plains. High-subsidence areas are generally located in the northern part of Garmsar, decreasing towards the southeast. The temporal and regional relationships of groundwater data and subsidence suggest that the general pattern of the subsidence in the Garmsar Plain is caused by overexploitation of groundwater that has led to widespread surface deformation. Since Garmsar is close to Tehran metropolis and the industrial boom in this city puts enormous pressure on water resources, there is an urgent need to curb extra groundwater extraction and manage water resources more wisely to decrease the speed of this unrepairable phenomenon in the area.
Environmental Resources Research , 2021
In order to evaluate soil water content and water uptake by corn plant roots (Single cross 260) u... more In order to evaluate soil water content and water uptake by corn plant roots (Single cross 260) under different soil moisture and water salinity stresses using the agrohydrological Soil-Water-Atmosphere-Plant (SWAP) model, an experiment was conducted in 2015 at the green house of the Agriculture Research Center of Shahrood, Iran. The statistical model employed was a split plot based on a randomized complete block design with three replications. The main plots consisted of three levels of irrigation; 50 (I 1) (full irrigation as the control), 75 (I 2) and 100% (I 3) of Total Available Water (TAW) depletion while the sub-plots consisted of three levels of salinity of irrigation water; 2 (S 1), 4 (S 2) and 6 (S 3) ds.m-1. The results showed a good correspondence between the simulated soil moisture, water uptake and measured values. The normalized root mean square error (nRMSE) and the root mean square error (RMSE) values of the predicted soil moisture were 4.58 and 24.96 and for the water uptake by the roots were 23.37 and 35.48, respectively. The R 2 of coefficient of simulation for water uptake by roots in different treatments were 0.38 to 0.8. The dataset of the predicted and measured values were close to the 1:1 scale line for both soil moisture and water uptake. This study indicated that the SWAP model can be used as a powerful tool to simulate field water cycle and evaluate irrigation practices. Accordingly, taking into account the existing conditions of the region such as weather and soil type and preparing scenarios based on possible management options, management strategies can be optimized according to the results achieved for the SWAP model simulation.
Environmental Resources Research , 2021
Mining activity is one of the major sources of heavy metal pollution of soil. Most mines are aban... more Mining activity is one of the major sources of heavy metal pollution of soil. Most mines are abandoned without any remediation and cause contamination of soil and water. Phytoremediation is an environment-friendly technology for the remediation of contaminated sites. In this work, native plant species were identified that can tolerate high concentrations of heavy metals and are useful for phytoremediation in an abandoned Pb-Zn mine in the north of Iran. Twelve plant species and the corresponding soils were collected and analyzed for As, Cd, Co, Cr, Cu, Mo, Pb, Sb, Ni and Zn contents using inductively coupled plasma mass spectroscopy (ICP-MS). In order to measure the bioavailability of heavy metals for plants uptake, DTPA extraction of heavy metals were determined. Then, the physiochemical characteristics of the soil samples were measured and the translocation factors (TFs) and bio-concentration factors (BFs) were determined. The soil samples were alkaline, and exhibited low electrical conductivity, high cation-exchange capacity, moderate organic carbon content, and clay loam texture. All samples exceeded the soil toxicity thresholds for AS, Cd, Pb, Sb, and Zn. The results indicate that Stachys byzantina has the ability to accumulate significant amounts of Pb in its shoot. The average concentrations of Pb in the soil, shoot, and root were 15472mg kg-1 , 1797 mg kg-1 , and 371 mg kg-1 , respectively, with TF value of 4.8 and BF value of 0.1. Therefore, S. byzantina may have the potential to function as a Pb hyper-accumulator and merits further investigation.
Environmental Resources Research , 2021
In a majority of agricultural economics analyses, farmers' economic welfare is highlighted while ... more In a majority of agricultural economics analyses, farmers' economic welfare is highlighted while the environmental issues are largely ignored. Therefore, the purpose of the present study was to determine the optimal cropping pattern through an environmental approach in a case study in Kazeroun County, Fars, Iran. Data was collected from production costs statistics provided by the Statistics and Information Technology Bureau of Agriculture-Jahad Organization. The optimal cropping pattern was determined through the goal programming model with four goals of maximizing farmers' net return, minimizing the amount of used water, chemical fertilizers, and pesticides under three scenarios. The results indicated that the third scenario which involved the environmental goals specified by the Islamic Republic of Iran's 5 th Development Plan, was the optimal one. In this scenario, the use of water, chemical fertilizers and pesticides decreased by 4.4%, 4.72%, and 8.33% respectively while the net return increased by 10%. According to the results of the study, it is possible to increase the profit and productivity of resources with regard to environmental issues.
Environmental Resources Research , 2021
The purpose of the present research was Cadmium (Cd) and Lead (Pb) pollution assessment and monit... more The purpose of the present research was Cadmium (Cd) and Lead (Pb) pollution assessment and monitoring the spatial distribution of soil contamination around the municipal landfill site in southwest of Gorgan, Iran. Thus, in a systematic network with a distance of 250m, from 32 stations three samples of surface soil (0 to 20cm) were obtained and mixed together. In addition, three samples away from the landfill with similar characteristics and geology were used as control. The concentration of heavy metals for the samples was determined using nitric acid and hydrochloric acid and atomic absorption spectrometry. Mean concentrations of Cd and Pb in the soil around the landfill site were 0.37 and 17.31 mg/kg respectively. The total concentration of Cd and Pb was higher than the control areas. There was a positive correlation between Cd and Pb showing these elements in the soil are from the same origin. Based on our research, soil in the landfill area has a moderate ecological risk index, which is about 120. The central parts of the study area have higher concentrations of Cd and Pb than southern parts due to the slope and runoff of the waste leachate. In general, there was an increase in the concentration of Cd and Pb in the sampling sites compared to the control site.
Environmental Resources Research , 2021
Water as a major necessity of sustainable development is essential for agricultural production an... more Water as a major necessity of sustainable development is essential for agricultural production and food security. Increasing water productivity, especially in agriculture, is one of the key issues for optimum water resource management. The present study applied a Stochastic Metafrontier Model to estimate Technical Efficiency (TE) and Technology Gap Ratio (TGR) of agricultural production from selected countries. The frontier and metafrontier production functions of 27 countries from 2011 to 2016 were used for estimation of the TE. The results showed that the mean of group efficiency ranged from 0.32 to 0.83 and the mean of technology gap ratio based on water crisis indicator in three groups were 0.37, 0.39 and 0.44, respectively. Considering the global water scarcity mainly in arid and semi-arid environments, it is vital to seek appropriate policies directed towards the provision of technology for irrigation infrastructures that would enhance resource use efficiency.
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Papers by Environmental Resources Research
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