Journal of Range and Watershed Managment

Abstract The Baliqlu Chay River watershed in Ardabil Province is a key water source for regional demands. In this study, the role of climate change and human activities on streamflow is examined by using hydrological indices and trend analysis over the period 1991-2021. Monthly, seasonal, and annual climatic and discharge variables were assessed for trends using the Mann-Kendall trend test and Sen's slope estimator. Results indicate streamflow is controlled by seasonal snowmelt, groundwater reliance, and the controlling impact of the Yamchi Dam. Moreover, the high flow variability observed at the Yamchi Station, as indicated by elevated standard deviation and coefficient of variation values, suggests an increased risk of flooding in this area. Trend analysis results over the 30-year statistical period reveal a decreasing trend in annual precipitation at the Ardabil and Nir stations, although these trends are not statistically significant at the 99% and 95% confidence levels. In contrast, a statistically significant increasing trend in annual precipitation was detected at the synoptic station in Sareyn at the 99% confidence level. Additionally, the annual temperature increase at all stations was found to be statistically significant at the 99% confidence level. The assessment of streamflow trends on an annual scale at the Nirchay and Yamchi Dam hydrometric stations indicates a statistically significant decreasing trend at the 1% level (p-value ≤ 0.01). These results emphasize the urgent need for sustainable water management strategies, including optimization of resource use, revised consumption patterns, and improved operation of the Yamchi Dam. Such interventions are essential to reduce the negative impacts of climate change and anthropogenic pressures on the river’s hydrological regime.

Abstract Rangelands, as one of the most important natural ecosystems, play a crucial role in maintaining biodiversity and supporting the livelihoods of local communities. This study aimed to identify and analyze the barriers to sustainable rangeland management in the Qashqai nomadic communities of Abadeh County. Using a qualitative approach and grounded theory methodology (Strauss and Corbin), data were collected through semi-structured interviews with local stakeholders. Nineteen participants were selected through snowball sampling based on theoretical saturation. Data were analyzed using open, axial, and selective coding, resulting in a conceptual model outlining the key obstacles to sustainable rangeland management in Qashqai nomadic communities of Abadeh County. The findings revealed that the main barriers to sustainable rangeland management include causal conditions (increasing pressure on rangelands, structural and systemic problems, and environmental degradation), contextual conditions (ecological and geographical limitations, socioeconomic challenges, and weak infrastructure and management), and intervening factors (external influences, technological and social transformations, crises and dysfunctions, and regional cooperation). Improvement strategies comprised rangeland ecosystem restoration, empowerment and participation of local communities, economic and legal support, sustainable development, and international cooperation. The consequences included ecological improvement, socioeconomic prosperity, reduced pressure on rangelands, increased investment, and pollution mitigation. The results emphasize the necessity of integrating indigenous knowledge with modern technologies and strengthening the participation of nomadic communities in decision-making to achieve sustainable rangeland management. This study offers practical strategies to improve rangeland management and ensure their long-term sustainability in the region.

Abstract Carbon storage in terrestrial ecosystems is an important part of global carbon storage and plays a vital role in mitigating climate change. The purpose of this research is to investigate the effects of different types of land uses/land covers (dense rangelands, semi-dense rangelands, low density rangelands, barren lands and agricultural lands) on the amount of soil carbon and plant biomass sequestration as an important ecosystem service in Sefiddasht watershed in in Chaharmahal va Bakhtiari province. Sampling of soil and vegetation was done randomly and systematically. For this purpose, 60 plots of 4 square meters were used for collecting soil, plant material and litter. Plant biomass was sampled by direct measurement method. Soil samples were also collected from the depth of 0-30 cm and 20 samples in each area. The results showed that there is a significant difference between the investigated regions in terms of total carbon storage. The total carbon storage from the highest to the lowest in order includes dense rangelands (46.42 tons/ha), semi-dense rangelands (38.49 tons/ha), agricultural lands (31.62 tons/ha), low-density rangelands (26.12 tons) per hectare) and barren lands (17.21 tons per hectare). The economic value of the total carbon storage per hectare of the examined uses, including dense rangelands, semi-dense rangelands, agricultural lands, low-dense rangelands, and barren lands, was determined to be $5446, $4516, $3710, $3065, and $2019, respectively. Therefore, it can be concluded that the implementation of appropriate policies to prevent or minimize the conversion of land uses with a higher carbon storage capacity to land uses with a lower carbon storage capacity is of particular importance.

Abstract Background: Coping with climate change (CC) is part of the way to face this phenomenon. This depends on the understanding of CC and the degree of adaptability to it.
Objective: The research was conducted with the aim of measuring the level of nomads' understanding (NU) of CCe and their adaptation strategies (AS) in the face of CC.
Research method: The research was descriptive and the data collection tool was a questionnaire whose items were obtained based on interviews.
Findings: NU of the effects of CC is not the same. According to them, CC has had the most obvious impact on vegetation. The priority of AS is also different in the face of CC. A positive relationship was observed between understanding the effects of CC and the degree of adaptability in facing CC. Nomads who had a better understanding of the effects of CC have used livestock management strategies to adapt to it. Age and history of animal husbandry had a positive relationship with the level of understanding of the effects of CC. A negative and significant relationship was also observed between the number of animals and the degree of compatibility.
Conclusion: The NU of CC and its effects on the ecology of the environment is an important starting point in dealing with the negative effects of CC and choosing appropriate strategies to adapt or deal with it. So that the selection of suitable adaptation methods by the nomads reduces the vulnerability of CC on the condition of livestock and rangeland.

Abstract GCM models are widely used to assess climate change on a global scale, but outputs of these models are not sufficient and accurate to assess climate change at local and regional levels. Therefore, in this study, SDSM model was used for micro-scaling of CanESM2 model data and climate conditions of Semirom region based on three scenarios of RCP2.6, RCP4.5 and RCP8.5 in the period 2020 to 2100. The results of model evaluation based on NCEP database showed that the model was more accurate in estimating and predicting temperature data especially mean temperature. Comparison of observation and simulated data of temperature and precipitation of GCMs in the baseline period (1980 to 2005) based on NCEP predictor variables showed the mean correlation of precipitation data of 0.52, mean temperature of 0.88, maximum temperature of 0.80 and minimum temperature of 0.70 for validation and verification periods. The results of the estimation of precipitation variations in different scenarios also predicted a decrease of at least 7.24% and a maximum of 18.55% for the time period of 2020 to 2100 compared to the baseline period (1980-2005). The results of precipitation prediction also show the changes of precipitation pattern. The comparison of the scenarios also shows that the RCP2.6 scenario as the most optimistic scenario has the least rainfall while the RCP8.5 scenario predicts the highest rainfall reduction. Examination of the predicted changes in temperature also shows an increase for the mean, minimum and maximum temperatures,

Abstract The present research aims to assess climate change in the Minab plain and its effect on groundwater level variability in the future period. Climate change was explored by the climatic model CanESM2 using the SDSM4.2 software package, and the effect of climate change on groundwater resources was quantitatively modeled in the GMS10.0.5 software package under the emission scenarios of RCP2.6, RCP4.5, and RCP8.5. The results for the effect of climate change in the future period in the context of these scenarios showed that temperature will increase by 1.88ºC, 2.60ºC, and 4.28ºC and precipitation will decrease by 34.19%, 42.08%, and 59.43% versus the reference year, respectively. The results for the application of the climatic scenarios using the groundwater model revealed that due to the decline of precipitation in this period, mean groundwater level balance in the future periods leading to 2019, 2024, 2029, and 2035 versus the reference year (2003-2004) will be -13.99, -19.003, -22.70, and -25.61 m/yr in RCP2.6, -13.99, -18.95, -22.75, and -24.73 m/yr in RCP4.5, and -14.23, -19.22, -22.003, and -25.46 m/yr in RCP8.5, respectively. This shows that the drawdown will be being aggravated over time. Finally, this decline of precipitation and rise in temperature due to climate change and the subsequent increase in water abstraction for different uses will result in the growing depletion of the groundwater tables in Minab. So, it is recommended to planners and authorities to adopt strategies for adaptation to new climatic conditions and water scarcity and accommodate themselves with future conditions.

Abstract Climate change has been a serious issue in the last two decades, and many studies have focused on its various aspects. In the present study, the effect of climate change on the distribution of Bromus tomentellus was investigated. To do this, 19 bioclimatic variables and three physiographic variables and logistic regression model were used to quantify climate change in 2050 and to study its effects on the change of B.tomentellus species. First, using 17 synoptic stations in and near the province, a database of precipitation variables, night temperature, daily temperature and average temperature was formed and 19 climatic measures were calculated. Also using the digital model of height, with an accuracy of 30 meters; physiographic variables of slope, direction and height were prepared. Then, the presence and absence points of the species were determined and using logistic regression, its vegetative behavior was determined and the modeled map and related equations in the current conditions were calculated. Using current equations and inserting data extracted from the Worldclime database; the future distribution map for 2050 was generated under RCP4.5 and RCP8.5 climate scenarios. The results showed; the average annual temperature (BIO1), the annual temperature range (BIO7) and the average temperature of the coldest season (BIO11) are the most important for habitat fit, the values of which increase with increasing climatic conditions. Average annual temperature in places with a probability of more than 75%; over the next three decades, it will rise by 1.6 to 1.2 degrees Celsius.

Abstract Water deficit caused by climate change due to the extent and magnitude of the social and economic damages it causes, is one of the most dangerous natural disasters that causes irreparable damage to the agricultural and water resources of the country. In other words, it has devastating effects on the productive, economic, social and environmental sectors. The purpose of this study was to analyze the components of resilience and present a model of resilience of the local community in the face of climate change. The statistical population of the study consisted of rural community of Nodushan watershed which was used for sample size of Cochran formula and 100 people were surveyed based on a researcher-made questionnaire. The Resilience Component Analysis Questionnaire was used. Data were analyzed using SPSS25 and LISREL8.8 software. To investigate the fit of the resilience component measurement model, the data was analyzed used LISREL software. The results showed that among the resiliency indices, the indicators of "local networks" and "financial and infrastructure" with 91 percent and 84 percent path coefficients were better than other indices, respectively. "Compatible management status" and "risk-taking" with 10 percent and 8 percent path coefficients, respectively, are not appropriate. Also, results showed that the goodness-of-fit indices had values and confirmed the resilience dimension measurement model with the data. Therefore, it can be acknowledged that the results of this study can in actions and can be effective in promoting and adopting climate change crisis mitigation mechanisms to create resilience in the local community.

Abstract Intergovernmental Panel on Climate Change report shows that the world average temperature has increased to 0.6 ° C ± 0.2 ° C in the twentieth century. Therefore, long-term prediction of climate variables and the consideration of measures to mitigate the adverse effects of climate change is evident. The SDSM model was used to downscale observation data of the minimum and maximum temperatures of the Vazvan Meyme station in Isfahan province. The CanESM2 global model data under new emission scenarios: RCP2.6, RCP4.5, and RCP8.5 are used to predict the near future (2006-2036), mid-term (2037-2078) and far-away future (2079-2100). The studies show the ability of the SDSM model to model maximum and minimum temperatures in the base period. The results of this study necessary indicate that as we get closer to the 21st century, the minimum and the maximum temperatures increase in the area of study. The average maximum temperature changes will have the highest increase under the RCP8.5 scenarios in the (2079-2100), in July, which will reach 7.9 ° C. The average changes in minimum temperature show the highest increase in August under the RCP8.5 scenarios. Therefore, considering that this temperature increase in future periods will affect the status of the study area, water resources, and natural resources. Planners and authorities of the relevant departments will take the necessary measures, such as measures to correct irrigation systems, methods for reducing evaporation and improving the cultivation system, to adjust the damage caused by heating or adapt to the new climatic conditions.

Abstract The climate change phenomenon is considered as one of the important environmental challenges in the 21st century. The most impacts of this phenomenon are focused on industries and establishments such as agriculture and fishery that is depended on natural resources. Resilience considered as a practical approach for compatibility of this phenomenon and the creation of sustainable development. Since networks, especially formal networks such as institutional networks, can play a key role in creating and promoting resilience against climate change, the present study is conducted through a network analysis approach and with the aim of fundamental analyses in the field of resilience against climate change. The statistical population of the present study consists of the small beneficiary owners in Tarom County in Zanjan province. Through network analysis, the dominant statistical method of the research considered as the sociometry and extraction of network centrality indices. According to the findings, two agencies namely Agriculture Jihad Organization, and Banks and Credit and Financial Institution play a major role in the educational information network and technical services, respectively. In the financial facilities network, banks and credit and financial institutions, and the Agricultural Jihad Organization rank first and second in providing the financial services and consulting, respectively. The findings demonstrated that many institutions that can play a constructive role in the field of resilience against climate change, such as the insurance organization, have been secluded and marginalized.

Abstract The climate change is the greatest environmental challenge facing the world today. The prediction of the effect of climate change on the distribution of sensitive and valuable plant species is considered important in the management and conservation of them. Onosma L. as a very rich taxa from Lithospermeae Dumort. tribe in Boraginaceae family including 52 species in Iran wich more than half of them are endemic to Iran. The Onosma sabalanica Ponert. and Onosma cornuta H. Riedl. are the rare and endemic species of Onosma L. in Iran. Objective of the present study was to predict the effects of the climate change on the spatial distribution of these plants at future. In this regard, with using species distribution model's tool (SDM), different algorithms (GLM, GAM, GBM, RF, CTA, FDA, MARS, ANN, SRE) in different optimistic (RCP2.6) and pessimistic (RCP8.5) scenarios predicted the future spatial distribution of this species for 2050 by an ensemble model in R statistical software. The results showed that the performance of all models based on TSS index was excellent and modeling of the distribution of the species had been done with high statistical reliability. The results also represented that the distribution of these species in both optimistic and pessimistic scenarios of 2050 had been significantly reduced which requires to apply strategies for protecting of this valuable plants.

Abstract All rural and nomadic communities reside in natural watershed areas and, based on the specific climatic and geological conditions that each catchment area has, they are useful for living. Today, there is a danger to the livelihoods of non-residents as well as climate change caused by human activities, in other words, global warming due to the burning of fossil fuels. Accordingly, in this study, using the indices defined in the natural, social, physical, human and economic parameters, we examine the amount of five effective capital in the capacity of watershed adaptation to the climate change phenomenon in the three villages of Haji Abad, Gisur and Noodat Pashang In Gonabad city. In this study, due to climate homogeneity, 3 villages in the dry climate of Gonabad city have been selected. In this research, based on the questionnaire, the size of each of the five indicators and the organized interviews with the target groups in the three villages of the desert region were 3.13, 3.39, 3.14, 3.26, 7.2 was calculated. Also, using the Freeman test, it was found that there is a significant difference between different capital, which, respectively, social, human, physical, natural and economic, have the greatest impact on the capacity of aquaculture adaptation, so it is better to solve The watershed problem has used social and human capital to inflate other (physical, natural, and economic) capital

Abstract Trend and stationarity analyses of hydrological variables are useful tools for understanding climate change and may provide useful information about likely changes in the future. As non-stationary of time series can occur due to various reasons such as trend existence in data; therefor, in current study the non-parametric Mann-Kendall trend test was used to detect the trend of the data. A corrector approach, namely “TFPW” was utilized to modify the effects of serial dependence of the time series on the trend detection results. The stationarity of time series was tested by unit root and stationarity tests to evaluate the relationship between trend and stationarity of the time series. The results showed that the surface flows of all of the studied rivers have a decreasing trend; although the significant trends changed to insignificant ones after applying TFPW approach. The results of the stationarity tests showed non-stationary time series for all of the sites after removing the serial dependence of the series, which is a sign of the lack of trend existence in the time series; however, Latian station (Lar river) reveals non-stationarity after applying TFPW which may be originated from the existence of abrupt changes in the series. The findings of current study can help the planners and policy-makers and water resources managers to cope with climate change in the future.

Abstract Present study is aimed at forecasting and comparison of future climate change by using GCM model (General circulation model) under different climate scenarios in Talar watershed of Mazandaran province. Regarding the data of existing stations, to study the climate change phenomenon in Talar watershed, the LARS-WG5 model and 3 climate scenarios i.e. A1B, A2, B1, each in three emission series i.e. 2011-2026, 2046-2061, and 2080-2095, that were extracted from Gharakhayl regional synoptic stations in Quaemshahr, were used and the base year was considered 1992-2007( for a 15- year duration). Since this model is one of the most authentic statistical downscaling methods and its data is produced in three phases of calibration, evaluation and development of meteorological data, it was applied for research in present study. According to the findings, the most precipitaion changes occurred in May and October and the most severe reductive changes occurred in 2080-2095, the result of which warns about seasonal floods in rainy months and drought or water shortage in dry months in the relevant watershed study area. Besides, in future in June, July, August, and September temperature increase will be experienced but in January and February, the minimum simulated tempreture mean will be observed.

Abstract Global warming and climate change have drawn special attention to soil and its potential for stable carbon sequestration. Soils are the largest stores of carbon in terrestrial carbon cycle and contain about three times more carbon than vegetation cover and two times more than that of atmosphere. Studying the effects of grazing on soil carbon storage is important because of the major role soil organic carbon has in production. Grazing is potent for changing the carbon storage of rangeland ecosystems. In this research, the effect of different grazing intensities on carbon sequestration and nitrogen stabilization in pastures cultivated with Atriplex canescens in Shahriar was studied. Soil and plant samplings were done in low, moderate and high grazing intensity areas as well as exclosure, using randomized – systematic method. Soil samples were taken from 0-10, 10-30 and 30-100 Cm depths of 20 soil profiles. In each soil sample, stone percent, bulk density, organic carbon and nitrogen were calculated. Data analysis was done using one – way ANOVA and Duncan test in SPSS 17 software. Results showed that all three grazing intensities have caused significant reduction in carbon and nitrogen of soil.

Abstract Within the climate change debate and its probable impacts on water resources systems, design and operation of management plans based on the assumption of stationary hydrology may cause serious challenge to accurately predict future supplies. Therefore this case study is trying to assess trend in hydroclimatic variables of Karkheh Rivers upstream by applying modified Mann-Kendall trend test on long term daily time series of temperature, precipitation and discharge. Temperature variables are mostly showing meaningful increasing trends but observed changes in assessed stations were not spatially uniform for precipitation. Streamflow variables depict a decreasing trend, though more noticeable in base flows. Decreasing trend is meaningful for annual discharge median in Holailan at 90% confidence level. Total yearly precipitation, number of precipitation days and number of days with precipitation equal to, or greater than, 10 mm/d show the most correlation with stream flow variables. Comparing monthly discharge with temperature and precipitation variables in the studied gages indicates a time-delay in system response to inputs. This may related to snowmelt contributions or contributions of water into streams after passing through different hydrological pathways such as groundwater. Some parts of streamflow changes, especially about base flows, is not completely verified by precipitation changes and can be attributed to changes in temperature or another factors such as groundwater overexploitation.
 
 

Abstract Investigation of drought event has a great importance in the natural resources management and planning water resources management. In this research, the effect of the climate change on drought characteristics in northwest of Iran was investigated using the HadCM3 model under A2 scenario. The statistical downscaling was executed using SDSM 4.2.9 and observed daily precipitation, observed predictors and large-scale predictors derived from the HadCM3 model. Afterwards the SPI was calculated for different time scales of 3, 12, 24 and 48 months in the observed period of 1977-2006 and three periods of 2007-2036, 2037-2066 and 2067-2096. Obtained results show that the mean annual precipitation at the stations of Ardebil, Khoy and Oroomieh was decreased in the future periods and it was also increased at the station of Tabriz in the future period. The Ardebil station with the depletion of 97 mm (32 %) in the fourth period than the observed period has maximum rate of the depletion. The results also show that the drought occurrence with more intensity, duration and frequency can occur in the future periods. The comparison of the results between different stations shows that the Ardebil station has the most intensity of dry period in time scales of 3, 12 and 24 months based on the maximum cumulative intensity of dry periods among the stations. On the time scale of 48 months, the Oroomieh station with the cumulative intensity of -92.78, has the most intensity of dry period between the different stations.

Abstract Evaluation soil erosion is an important matter to protecting it from destroying in future due to the excessive use of the inherent capacity of soil and also improper management. Therefore, in this study land vulnerability related to water and wind erosion of Abyek for crops and pasture land has been evaluated, using Raizal model as one of the Microleis sub-models. Morphological and physical and chemical analysis data were obtained of studying and evaluating the 32 soil profiles. Agricultural - climatic and management information including temperature and precipitation data were collected from Bagh-e-Kosar climatological station for the last 17 years. To study the effect of climatic changes in the assessment of land area for the year 2080 AD (for 70 future year), the reports of International Panel on Climate Change (IPCC) allocated to West Asia have been used. Utilization types considered for evaluation, including wheat, corn, barley and alfalfa. The results obtained of Land vulnerability evaluation studies related to water and wind erosion using Raizal model part have been prepared as maps in the GIS environment. Information obtained from Land vulnerability models related to wind erosion for crops and pasture land, also implies vulnerability risk fora wide percent of the region lands under the current management, that the results evaluation of the proposed management methods express the improvement of destroying ability classes.

Abstract Climate change is defined as long term and irreversible changes in the climatic behavior
of a region. Many studies have been conducted in different regions of the world on climate
change. The results of these studies show considerable changes in climatic factors especially
in precipitation and temperature. In this research, the trend of changes in annual and seasonal
rainfall and temperature in 24 synoptic stations over a 50-year data period (1956-2005) was
investigated in Iran. The Mann- Kendall test and linear regression technique were used to analyze
the trend of changes in climatic factors. The results showed both increasing and decreasing
trends in annual rainfall at various regions of Iran. Annual rainfall in northern slopes of Alborz
and western slopes of the Zagros Mountain as well as in eastern and southeast parts of Iran had
a decreasing trend while in the central of Iran the trend of changes was increasing. In southern
region of Iran the rainfall had an increasing trend. The results also showed that temperature in
most of the studied stations over the considered period was increasing. The highest and lowest
changes in temperature were seen in the mean temperature of summer and winter, respectively.
Ahwaz and Khorramabad stations had a decreasing trend and over all seasons would go toward
more cooling. The temperature trend in Oromiye was decreasing in autumn and summer while
Shahrekord and Bandar abbas had the same trend in summer and winter.