Deficiency of water with suitable quality is a vital challenge in urban and specially in arid and semiarid regions. The aim of this study is to assess temporal and spatial VARIATION of drinking groundwater quality and quantity in County of Mallard in Tehran province. Mallard is a County at margin of Central Iran Plateau. The data used in this research comprises of 14 parameters in 31 drinking water wells that obtained during a 6-year interval. Spatiotemporal VARIATION in these wells were analyzed by applying Parametric and nonparametric statistical techniques including one-way ANOVA, Kruskal-Wallis, independent-samples T-test, Mann-Whitney. The results reveals that concentration of sulfate, chlorine, bicarbonate, electrical conductivity, TDS, sodium and fluorine in dry and wet periods have significant difference. Effects of space on quality of groundwater in Mallard suggest that boring wells in pyroclastic, tuff and sandy lime (E2) Formations meaningfully and at level of Percent 95 have the most impact on mineral concentration of water quality parameters. Furthermore, concentration of nitrate has increased in cultivation and urban-rural land use and the level of pH in cultivating and urban-rural use has decreased significant and at level of Percent 95 in comparison to other lands.

Albedo is one of the important factors affecting the energy balance of lakes. This study investigates the spatiotemporal VARIATION of shortwave albedo over the entire boundary of Lake Urmia. For this purpose, first, the boundaries of the lake water body, salt flats, and bare lands have been extracted. Secondly, monthly time series of shortwave albedo have been analyzed using the MODIS albedo product (MCD43A3). The validation results showed that MODIS data underestimates the lake surface albedo. Moreover, along with the significant lake level drop from 2008 to 2017 (compared to the previous decade), the surface albedo of Lake Urmia has extremely increased (up to 150%). This, in turn, can lead to a decrease in surface temperature, evaporation, and thermal storage capacity of the lake and impair its function in regulating the micro-climate of its surrounding region. Despite an increase in the bare land and salt flat areas, albedo of these surfaces have remained pretty constant and no trend has been observed during the study period. Results of this study indicated the inefficiency of the MODIS albedo data (MCD43A3 v. 6) in monitoring Lake Urmia albedo. Findings can also provide insights into the performance improvement of the next version of MODIS albedo products, particularly over saline lakes.

Vineyards are intensively managed with machinery, leading to negative impacts on soil compaction and moisture, which can decrease grape productivity and quality. However, there is a lack of investigations at the Pedon scale related to the SPATIO-TEMPORAL distribution of soil compaction in vineyards. The aim of the study was to quantify the impacts of tractor traffic passes on Bulk Density(BD) and Soil Water Content (SWC), in a Croatian vineyard. Soil properties were measured at different depths (0-10, 10-20 and 20-30 cm), seasons (before, during and after summer), and at three different zones subject to different management actions: Grass Covered inter-row (GC), Tilled inter-row (T) and tilled row (R). The main effects of tractor traffic passes were found at the 0-10 cm soil depth. Soil BD was significantly higher after summer than before and during summer. At 0-10 cm, SWC was significantly lower during summer than before and after. At 10-20 and 20-30 cm depths, SWC was higher in all zones, showing no significant differences between them at each depth. Significant positive correlations between BD and SWC were identified in the T zone after summer, although increased traffic decreased the SWC. Wheel traffic increased BD, which we can attribute to the high SWC. Nevertheless, this increase was agronomically not relevant. Such findings should be considered in order to control soil compaction in vineyards through environmentally-friendly soil management practices.

The present study was conducted to assess the changes in Iran's drought severity for the duration of 1964 to 2014. For this purpose, the spatial distribution of drought was annually and seasonally evaluated using climate data from 26 synoptic stations over Iranian territory based on standardized precipitation index (SPI). In this regard, the climate classification in the study area was performed applying Dermartone method. Moreover, the annual and seasonal values of SPI were calculated for the whole Iranian territory and each climate region. The SPI index for monotonic trend was calculated in each climate region utilizing Mann-Kendall and Theil Sen estimators. Our results implied that the minimum and maximum values of SPI (-3. 86 and 2. 89, respectively) appeared during spring in dry and Mediterranean climate regions. In addition, the maximum and minimum values of annual continuous SPI appeared in 1999-2004 and 1974-1982, respectively. The maximum and minimum values of seasonal continuous SPI also appeared for a duration of 9 years during summers respectively in the period of 1977 to 1985 and springs in the period of 2006 to 2014. The application of Mann-Kendall and Theil Sen estimator analyses revealed that 9 out of 26 stations had a significant decreasing SPI trend. Moreover, the annual and seasonal time series in moderately dry regions indicated a meaningfully decreasing trend in winter and annual SPI. Additionally, winter, spring, autumn and annual values of SPI had a meaningful decreasing trend in the Mediterranean climate region. In dry and very wet climate regions, no obvious trend was detected for the annual or seasonal SPI index.

The forests of the Zagros are one of the most important and fundamental treasures of the country, which plays a key role in providing water and soil resources in this region. The geographical distribution of different plant communities is dramatically dependent on climatic conditions. Changes in climatic elements, such as precipitation, can cause long-term and short-term reactions of various plant colonie. The main purpose of this study is to reveal the spatial changeability of Lorestan forest NDVI index in response to rainfall changes. The vegetation index of Lorestan was detected using Landsat 8 and 5 imageries during 2000-2017. The monthly and annual rainfall also has been obtained using accumulated monthly rainfall of 9 synoptic stations of Lorestan province. The Pearson correlation matrix has been used to analyze the relationship between annual VARIATION of forest cover area and qnnual rainfall index. The results showed that the EVI> 0. 4 threshold can be considered as the threshold of the province's forest cover. The correlation analysis showed that the 18-year time series of forest cover, was correlated with the spatial distribution of annual rainfall in Lorestan Province by 0. 72 that is significant in 0. 95 confidence level (P_value=0. 05). Spatial analysis of the implementation of the greenness estimator model showed that the rainfall threshold of oak greenery (EVI> 0. 4) was equal to 320 mm, above which the EVI index increased by 0. 88 for each millimeter of rainfall growth of the studied oaks.

The study of water resources and reviewing periodic and spatial changes in the quality of water in aquatic ecosystems are of important necessity due to the reasons including, climate change, water resource constraints, and increased human water requirements. Given the fact that Koohsar Lake water in Zanjan Province is one of the sources of drinking water in the region, the present study aimed to measure the values ​​of 19 parameters of water quality in two seasons of summer and spring at four stations. The samples were transferred to a laboratory under steady-state and sunlight conditions and analyzed according to the standard methods. Statistical analyses were performed using SPSS software. Moreover, the study applied factor analysis using principle components to analyze the variance of data. In addition, the values ​​of the parameters were compared with the permissible limits of drinking water of national standard. The results indicated a significant difference between the parameters studied at stations and different sampling times by repeated measurements. The results of factor analysis also showed that the total of three main components in the summer and spring were 96.573% and 98.581% of the variance of data respectively. The main parameters in the summer included Chlorophyll-a, Na, DO, pH, BOD, COD, TDS, EC, and nitrate. Also, EC, TDS, alkalinity, pH, COD, BOD, Ca, and ammonia were found as the main parameters in the spring. Also, it was found that except for the pH in the spring and at stations 3 and 4 which were below the standard minimum, the lake water in both seasons and all stations, in terms of parameters, was within the standard range and exhibited a good quality for drinking. Implications are discussed in light of the study findings.

Dust and smooth-sands which rise up from aerosols resources have always extreme environmental and economic damages. Since 1961, development of artificial forest (Haloxylon species) has stabilized dust formation in the critical center of south and south east of Kerman. Some reports from vegetation degradation, prompted researchers to use integrative methods for monitoring and modeling the possible changes of the vegetation index. This research has used remotely sensed data (bands: 3 and 4, TM/ETM, Landsat) to obtain Normalized Difference Vegetation Index (NDVI) and studied spatiotemporal density changes of the artificial forest (according to Moran spatial autocorrelation index during the years 1987, 2000, 2005, 2009 and 2014). Meanwhile, for assessment of the role of drought effects in Haloxylon forest degradation, daily precipitation dataset of Kerman has been analyzed by using Effective Drought Index (EDI) during 1980 to 2013. While, results show that the local average of NDVI has a meaningful decrease during the mentioned years, and the Moran index was increased and expanded the cluster patterns intensively. These changes represent some disorders in the initial linear structures of planted region as well as spotted Haloxylon trees. Expansion of droughts in association with human intervention increases the intense forest degradation in the borders of Tehran and Joopar roads. Indeed, the continuation of this process is hazardous, and considered as serious threat for developing the national plans such as Haftbagh-e-Alavi (east of region2).