Mehdi Panahi; Farhad Misaqi; Farid Ghanbari
Volume 15, Issue 3 , October 2017, , Pages 19-38
Introduction: Groundwater has long been the most ´trusted water source of human beings that is used in the agricultural and drinking sectors. In order to be aware of water condition and its optimized management, it is necessary to carefully examine groundwater level fluctuations and groundwater ...
Introduction: Groundwater has long been the most ´trusted water source of human beings that is used in the agricultural and drinking sectors. In order to be aware of water condition and its optimized management, it is necessary to carefully examine groundwater level fluctuations and groundwater quality that are influenced by different factors. While carefully monitoring the fluctuations and quality of groundwater, we can have reliable planning in water supply and source management. Therefore, this study aims to determine the trend of changes in quality parameters of groundwater of Shabestar plain in order to understand the quality of groundwater and to specify its application. Material and methods: In this study, in order to understand the quality of Shabestar plain’s groundwater and to specify its application, the chemical results of 15 qualitative variables of groundwater samples belonging to 13 stations located in the study area during the years 1382-1999 were compared while using non-parametric Mann-Kendall test, and then effect of the first-order autocorrelation was eliminated from the data series. Slope of the trend line was calculated by the age method. The qualitative parameters in this study are total anions, total cations, EC, SAR, CL--, , Ca2+, TH, Ph, TDS, , Na%, Na+, Mg2+ and K+ that are measured two times every year. Results and discussion: The results show that time series related to qualitative variables has ascending trend in most of stations (except Ali-shah station, Sefid-kamar station and low water months of Shabestar plain). They show positively significant trend at 5% level with 36 series (18%) in months of high level of water and with 17 series (9%) in months of low level of water. Furthermore, “Ali-shah” and “Sefid-kamar” stations have the highest rank in the highest negative trend in two months with high- and low- levels of water. The comparison of stations suggests that quality of Shabestar plain’s groundwater has critical condition in southern part of plain. Generally we can conclude that the quality of groundwater in the study area has decreased over time. The results achieved from investigating the values of time series correlation coefficients of qualitative variables with normal annual precipitation in the periods (1382-1388) show that none of the qualitative variables have a special significance at the 5% level with the amount of annual precipitation. The overall result of this section suggests the lack of relationship between annual precipitation and qualitative variables, while ground water level has almost steadily dropped with quality variables during common statistical years (1383-1391). Also, climatic variables such as rainfall, temperature and evaporation were not identified as factors in changing the qualitative characteristics of Shabestar plain’s groundwater and we come to this conclusion that their adverse changes were influenced by human factors. Conclusions: According to achieved results, we can say that if the current condition continues, it is not possible to steadily use groundwater source in Shabestar plain. Water quality will be negatively affected by the lack of treatment of urban and industrial wastewater, the release of agricultural wastes at the plains, adjacency to Urmia Lake, and the development of salt marsh.
Mehdi Panahi; Mina Taheri
Volume 14, Issue 1 , April 2016, , Pages 147-152
Analysis of raining days is one of the most significant elements of weather forecasting concerning agricultural section, since rainfall is the most unstable factors and shortage or rainfall during growing season may create heavy damages on agricultural section, particularly on dry farming. Necessity ...
Analysis of raining days is one of the most significant elements of weather forecasting concerning agricultural section, since rainfall is the most unstable factors and shortage or rainfall during growing season may create heavy damages on agricultural section, particularly on dry farming. Necessity of monitoring and analysis of this phenomenon could be demonstrated when we consider that a great part of agricultural lands depends on rainfall (amount and number of times) directly. Meanwhile, the significant performance of farming products will be related to raining method also in irrigation agriculture section. In the present study, number of raining days in Qazvin synoptic station, to analyze and study pathologically wheat cultivation by dry farming in the province, statistical models were used. Results of statistical analysis of number of raining days demonstrated that number of raining days in wet years in autumn cultivation season with recurrence interval of 5, 10, 25 and 50 year based on 29, 32, 39 and 44 days, respectively. Furthermore, in dry years, number of raining reliable days can be 8, 4, 0 and 1 day. In this regard, to investigate and study pathologically dry farming in the province, a statistical analysis was performed about raining days during growing season for wheat product. Findings of the analysis showed that in dry periods, dry farming is not appropriate and no reliable rainfall will be occurred during growing period.
Kamal Sadat Asilan; Seyed Ali Mohammad ModarresSanavy; Saeed Ghahary; Mehrdad Moradi Ghahderijan; Mahdi Panahi
Volume 12, Issue 4 , January 2015
In order to study theability of hull extracts of Iranian rice cultivars on germination and seedling growth of barnyard grass, two laboratory and greenhouse experiments were conducted ina completely randomized block design with factorial arrangement and three replications. This study wasundertaken to ...
In order to study theability of hull extracts of Iranian rice cultivars on germination and seedling growth of barnyard grass, two laboratory and greenhouse experiments were conducted ina completely randomized block design with factorial arrangement and three replications. This study wasundertaken to evaluate the allelopathic potential aqueous extract of 20 hull rice (Oryza sativa) cultivars on growth factor of barnyard grass (Echinochloa cruss-galli). This research was performed in 2007 at the Department of Agronomy of Tarbiat Modares University. Aqueous extract of hull rice in four concentrations (control, 5, 10 and 15%) were used for germination test and seedling growth of barnyard grass seeds. In the laboratory, we found that a few varieties product and released allelochemical for inhibiting and more cultivars stimulation growth of barnyard grass. Khazar variety showed the highest inhibition on germination percentage, germination rate, shoot length, root length, root dry weight and shoot dry weight. In addition, the breeding and domestic varieties were inhibitor and simulator of barnyard grass respectively. In the field experiment, Khazar cultivar reduced germination percentage, germination rate, root length, root dry weight, total dry weight and shoot dry weight of barnyard grass and Neda cultivar showed the greatest inhibition on shoot length. This study show that there are differences among the varieties of rice for allelopathic inhibition of barnyard grass seeds and genetic and morphological rice characteristics could be used as selection markets for allelopathic rice varieties and maybe used as a natural herbicide to reduce the population of barnyard grass in field. Increasing concentration of aqueous extract increased effects of inhibition and stimulation of various cultivars on barnyard grass. Survey morphological and genetic traits of rice varieties showed an existing relationship allelopathy potential of rice on barnyard grass.