مجله ترویج و توسعه آبخیزداری
پیاپی 34 (پاییز 1400)

Temporal and spatial distribution of snowfall was affected by climate changes. This study was carried out detection of snowfall trend in Namak Lake and Sefidroud watersheds. Trend detection was performed on 27 snow survey stations with sufficient data from 1957 to 2008. In this study, non-parametric Mann – Kendall test was used for assessment of existence and nonexistence trend and also Sen Test was for magnitude of trend. Out of 27 stations, all of which recorded snowfall in January, 12 stations show an increasing trend of snowfall. In February and March, 19 and 23 stations show a decreasing trend of snowfall depth, respectively. Therefore, 12 stations show an increasing trend of snowfall depth in April and Garmabdar and Sierra stations show a decreasing trend in 95% the level of confidence.

The dam is one of the huge development projects. With the implementation of this project, a lake will be formed behind the dam and a significant area of land will be submerged, which will create employment for many residents of the lake shore. Today, the construction of the dam has many socio-economic benefits and harms, and efforts are being made to obtain the most benefits and the least losses in the form of examining the effects of this project. The main purpose of this study is to assess the attitudes of residents of 14 villages upstream of the dam from the socio-economic effects of the construction of Mashoureh Dam in Lorestan province, on their lives. The statistical population in this study includes residents of villages upstream of Mashoureh Dam, 290 of whom were identified based on Cochran's formula. After collecting data, using SPSS software, a significant relationship was observed between the age variable of individuals with the level of satisfaction with the implementation of the project and the destination of immigrants in the future. The basis of the amount of land that goes under water was examined. According to the results, there was a significant difference in the attitude of residents in the two periods before and after the construction of the dam and the attitude of the two groups (based on the amount of water covered by their lands) and this indicates changes in socio-economic dimensions of residents due to Construction of a dam.

Water and wind erosion is one of the most important causes of soil loss. Understanding these interactions is essential for estimating soil quality and environmental impacts in areas with both types of soil erosion. Numerous factors affect the occurrence and process of water erosion. In this regard, dynamic climatic factors such as rainfall and wind have the most prominent role. Accordingly, water erosion control will be effective when sufficient knowledge is available about the effective factors. In this regard, the present manuscript has tried to address this issue from a different perspective and discuss the effects of different climatic factors on water erosion by analytically reviewing existing literature. The results of the review showed that among the climatic factors affecting water erosion, the role of rainfall on runoff production and soil loss had been paid more attention, and the role of other variables such as wind on behavioral changes in water erosion has not been considered. While in the presence of wind, the behavior of raindrops is changing and undoubtedly affects the process of water erosion and hydrological components. Changes in droplet diameter, velocity, angle of attack, and kinetic energy of rain can play an essential role in changing water erosion, especially splash erosion. However, accurate identification of effective and influential factors can provide beneficial analysis to experts, managers, and executives for modeling and ultimately proper management of the water erosion process.

Water has a very fundamental and vital role for human life and is the main element of human civilization and cultural flourishing. Religious beliefs and values advise proper planning for water consumption and liken it to life. The preservation of any civilization depends on the preservation of the water resources of that land. Hence, this sense of need necessitates a comprehensive and comprehensive look at the revelatory teachings and the role and importance of water. Certainly the importance and necessity of preserving water resources is not hidden from any living thing, looking at the advice of the Qur'an creates an understanding of how and with what strategies and ideas can be done to preserve it. In this article, the library method is used as well as the use of authentic religious books and sources, including Quranic verses, authentic meanings and interpretations, and Islamic traditions. Examining the verses and hadiths, we come to the conclusion that the life of all living beings depends on water, the source of which is rain from the sky. At present and in the future, anyone can hope that his power and glory will increase day by day if he has more water resources and strives in the proper management of water conservation and consumption and leads it to productivity. Therefore, in this regard, all human beings, especially scientists and statesmen, must have careful short-term and long-term planning for this so that future generations will also benefit from this divine blessing.

Sediment fingerprinting of water sediments is a suitable method to determine the share of resources in sediment production and as an erosion and sedimentation technique to identify the origin and movements of sediments in the river and relative estimation of soil erosion, which has increased in recent decades. A comprehensive review of the research background in the field of soil and sediment erosion, hybrid models, different tracers and sampling methods has been performed in various Iranian-scale origin studies. The available data were compared in order to achieve a unified view and provide effective tracers in the origin and determination of the share of sediment sources in sediment production in Iran's watersheds. The results showed that the source studies have been started since 2008 with the help of geochemical, radionuclide, trace elements, mineralogy, magnetic properties and enzymes. Most studies focus on the division of resources into process categories (uses and erosion). In the division of resources according to location (sub-basins), sub-basins close to the output had the largest relative share of sediment production. In sediment sampling, most studies have been based on the measurement of sediment at the backbone or the sample of the canal bed. Sampling volume was divided into three general categories and if granulometry of the sample is not considered in the research, a smaller sample size of 0.5-1 kg is preferred. Of all the studies, two were conducted at the local spatial scale (10 Km2) and the other at the medium spatial scale (10 to 10,000 Km2) and no research was conducted at the regional scale (greater than 10,000 Km2). The use of enzymes has been limited, due to the high cost and chemicals. The use of tracers such as radioactive elements is preferred due to its stability and heavy metals and rare elements due to lack of reaction and concentration changes. In order to reduce costs and analyze the results accurately, using laboratory analysis of sediment samples, the necessary detectors for sediment fingerprinting should be selected and then the concentration of the same detectors in sediment sources should be measured.

Drought is one of the most important climate phenomena which occurs in all climate conditions and most of the regions on the earth and brings in a lot of injuries to human and natural ecosystems. Therefore, it is important to investigate drought‛s characteristics including intensity, duration and its frequency and to find out their regional risk and forecasting, too. For this reason, some of rain gauge stations in Kheirabad watershed in which their data had been recorded until the end of water years 2011-2012, were selected. Drought conditions for each station were investigated for four different periods including three monthly and one annual periods, using Standardized Prediction Index. Then, drought prediction was performed using SPI values modeling using ARIMA and SARIMA time series. The results showed that in most of the studied time periods, the droughts in the Khyrababad basin are often of medium drought and wet years are of the same type. Study of the persistence of dry and wet periods in selected stations indicates that drought and wet years are more likely to be 1 and 2 years old and have more frequency than other dry and wet periods but the continuity of the normal situation, even for 5 years or more, has been observed in some stations, including the Boyeri and the Nazmakan. The results of drought prediction using time series show that the ARIMA model can better predict SPI values and increase the time interval from 12 months to 48 months more appropriate prediction. Also, the results of the evaluation of the models show that by increasing the time scale from 12 months to 48 months, the slope of the regression line and the MAE and RMSE values are lower.

The impact of these projects on local communities is directly correlated with their success rate and the success of the project is affected by the participation of local residents. This study was conducted to investigate the socio-economic impacts of natural resource and watershed management projects under the influence of local indigenous residents of Mahdishahr county (in Semnan province-Iran). The statistical n in the quantitative part of the study consists of villagers residing in Artad village. Statistical sample size was determined by Cochran formula and 74 questionnaires were analyzed by using a comparison of residents' attitude and Factor Analysis method. In the qualitative part, the village council members and rural governors were assisted in data analysis and subject mapping and content analysis. Based on the results, residents' attitudes toward each of the four items showed a significant difference. The first statement, which is related to the socio-cultural factors and strategies used for participation in natural resource and watershed management projects indicated that the natural resource departments are currently lacking a proper strategy to participation attraction of the villagers (Attitude : Low) ; the project is largely funded by the Department of Natural Resources and Watershed Management (Attitude: high) and the participation rate in mechanical and biological operations has been poorly evaluated (Attitude: Low). These cases have made these projects partially successful. The results of the factor analysis showed that the first factor affecting people's attitude toward the socio-economic impacts of natural resource and watershed projects is that the socio-economic impacts of these projects are affected by the extent of local residents' participation. This component has a variance of 90.43% which indicates the high importance of participation.