---

Commonly almost in many research cases in which meteorological data is required the interpolation reconstruction have been used, because of lack or limitation of meteorological stations in the whole study area. The main object of present research is evaluation of different interpolation methods to prepare rainfall map of Esfahan province. We used normal rainfall data of province and regression, IDW, Spiline, Kriging methods. We used RMSE for determination of the best method rainfall Interpolation with comparing real and estimated data. The results show that the elevation has the lowest and the Kriging has the highest error in rainfall maps.

---

Abstract Climatic unfavorable conditions lead to limitation of activity. Therefore, application of climatic severity coefficient can lead to befitting distribution of economic potentialities. The climatic stress index is suitable scale for ranking of residential sites due to climatic severity coefficient. In this research by dint of ArcGIS 9.1 software, climatic data were analyzed and numeric maps of climatic stress index in cold and warm seasons were produced by Inverse Distance Weighted (IDW) interpolation method. Thereafter, quantity of these indices were extracted from the map on the basis of cites geographical location. Then cites of this Province have been ranked from 1 to 25 in cold and warm seasons out of consideration of index. Results of this research show that the climatic stress index can be used to give climatic hardness coefficient in any location. Investigation of mean of stress index in 25 sites of this Province show that, not only the number of cold months is more than those of warm month, but also hardness of cool in seven months of cold season is more severe of that in five months of warm season. Studying of monthly mean of climatic stress index shows that, Boldaji, Nafch and Chelgerd sites in cold season and Malkhalife and Lordegan sites in warm season have more hardness of climatic conditions.

---

Two deterministic methods [Radial Basis Functions (RBF) and Inverse Distance Weighting (IDW)], and two stochastic interpolation methods [Kriging and Co-Kriging] have been evaluated to estimate the annual precipitation in Ardebil Province. For this purpose, we used data taken from various stations across the province [4 synoptic stations, 1 climatological station and 24 rain gauges], over a decade (2005-1995). The performance of the above model was examined using cross validation and the indices of Mean Bias Error (MBE), Mean Absolute Error (MAE) and Root Mean Square Error (RMSE).Finally, to identify under-estimated and over-estimated areas of each method at elevations above the spatial distribution of stations, the output of each model was examined. The results suggested that Kriging model had lower errors than other methods and was more compatible with the elevation surfaces. Therefore, this method was identified as the best option for estimating f precipitation in areas without adequate data and intense topographic gradients in Ardebil Province.

---

Concerning the rates and changes in the properties of elements and physico-chemical characteristics of groundwater and describing prepared maps, they have played a major role in the quality management of groundwater resources, therefore based on this issue, appropriate measurement is needed to present for preventing excessive pollution of the aquifer area. There are various methods existing for monitoring and predicting the density of the physico-chemical characteristics of groundwater the selection of appropriate methods depends on the objective circumstances of the region and its data. In this research which was carried out in Plour plain located on part of Haraz–Polour river basin, sampling from qualitative chemical parameters was done and then nutrient concentrations such as nitrate, phosphate and sulfate in 37 different wells in the area were measured. Then using spatial interpolation methods such as ordinary Kriging (OK) geo-statistical methods and other certain techniques such as Inverse Distance Weight (IDW), Radial Basis Function (RBF), Local Polynomial Interpolation (LPI) and Global Polynomial Interpolation (GPI), we assessed the   concentration changes in spatial zones for elements of phosphate, nitrate and sulfate.

---

Geohydrology issues ranging from the water table is very important . Therefore, research is necessary to estimate the missing data .In this study nourabad plain the 11 wells was observed that all the annual statistics of the statistical interpolation method ( Krigng and co ) places no statistics are calculated. This study aims to predict the groundwater level fluctuations , using intelligent Bayesian networks and artificial neural networks has been modeled .For this purpose, the latitude and longitude on a monthly time scale as the input and output parameters were selected as the groundwater level fluctuations .Criteria of correlation coefficient , root mean square error and coefficient of Nash suttclif and performance models were used to assess. The results showed that the neural network model has a correlation coefficient ( 0.880 ) , root mean square error ( 0.024m) and the standard Nash suttclif ( 0.900 ) in step verification succeeded with considerable accuracy to estimate water level fluctuations would .

---

Climate knowledge and investigating in climatologic requirements of plants is taken into account as a the most salient factor in cultivation. It can be determined the climatic potential conditions in the various regions and utilize them to a large extent by investigating in agro-meteorology. In this research, it has been applied the Geographic Information System to generate the climatic potential maps for Zanjan Province. To this purpose, the 30-year statistical records of climatology/synoptic stations have been used in the province of Zanjan. It was determined the date of cultivation for each section of the province after obtaining the beginning date of autumn precipitations for each part of the province. In the next step, the rainfall element was used for producing the isohyets climatic maps of annual rainfall, rainfall in the germination, blossoming, and ripe periods. The isotherm climatic maps of germination’s suitable temperature, thermal tensions during the blossoming, ripe periods were provided for the whole province. In the long run, the climatic potential regionalization map of dry-farming wheat was produced through overlying the relevant maps by GIS. The outputs showed that the major suitable regions for dry-farming of wheat are in the South and Central areas of the province. In contrast, the regions located in the North of the province – upland and sharp steep regions of Alburz mountain chain - hold ordinary and feeble conditions in the light of wheat cultivation.

---

To doing this research, daily precipitation data from 188 synoptic, climatology and rain gauges stations in and out of Kurdistan province during 21/3/1961 to 19/1/2011 have been used. Daily precipitation interpolated on 6*6 km pixels by Kriging spatial statistic over Kurdistan province. One matrix with dimension 18203*811 has been created that located time (days) on the rows and column were pixels. For each pixels total monthly precipitation has been calculated. Data of ten teleconnection patterns extracted from NCEP/NCAR.  Linear regression has been used to detection correlation between precipitation and teleconnection patterns. The correlation tested in 95% confidence level. The results showed that correlation between precipitation and teleconnection patterns is significant in 95% confidence level. The extent and intensity of significant correlation go to head in autumn season. The impact of South Oscillation Index (SOI), North Sea Caspian Pattern (NCP) and East Atlantic and West Russia (EAWR) is high in autumn. In cold seasons, SOI has negative correlation while NCP and EAWR have positive correlation with precipitation. In warm seasons two recent indices have negative correlation with precipitation. In total, increase sea level pressure and geopotential height in 500 hPa over Western European parts and decrease over eastern Mediterranean, Caspian Sea and north Caspian result in increase precipitation in Kurdistan province during cold seasons. In contrast, increase sea level pressure and geopotential height in 500 hPa over northern part of Caspian Sea result in increase precipitation during warm seasons. 

---

Geotechnical studies with a minimum of experiments can prevent from many of the problems caused by drilling such as the cost and blasting enormous in gas pipes. The spatial interpolation methods were developed for these problems with different applications. In most research on interpolation, the data used that the coefficient of variation are low, so in this study we have tried capability mapping interpolation methods for data with the coefficient of variation is relatively high, such as resistance allowed the soil near the fault tested and the impact of clustering method to improve the zoning evaluated. Eram town in Tabriz city selected as a case study because of its proximity to the main fault with nonisotropic data's. For this purpose, in this study, various methods such as kriging, inverse distance weighted, radial basis functions, local polynomial for zoning and cluster analysis with Euclidean distance with minimum variance technique is used. The data used for soil authorized strength of 40 boreholes in the town of Tabriz city. Zoning for the first state is without clustering and second state is with clustering that the whole area is divided into three zones. The result shows clustering approach could improve results and estimates at least 2 percent of estimate and at least 5 percent of root mean square error. The interpolation methods, local polynomial function method is better than other methods.

---

Regarding to importance of Juniperus sites, it is important to estimation of tree density and spatial structure of them using Geostatic. This study was conducted in Golestan province, Chaharbagh with area of 60 ha. We refined a 15×20 grid and 300 plots (45×45 m²) were measured. The number of trees with diameter at breast height (DBH) <7.5 cm were considered. The results of the variogram analysis showed that the tree density parameter had a vigorous spatial structure. First, the spherical model was fitted on the variogram. Then, the estimations and mapping were done using Kriging and IDW approaches. Cross validation results of approaches showed that the estimation of tree density was unbiased and these methods can be used for mapping spatial distribution of tree density with acceptable precision. The Kriging method with RMSE of 6.8 tree.ha^-1 and 8.7% had the better performance in comparison with IDW with RMSE of 7.5 tree.ha^-1 and 9.5%. So, the Kriging method is useable in ChaharBagh for tree density mapping. 

---

Soil chemical properties variability and value of their variability have specific importance in sustainable production. Measuring methods of these which usually possible with soil testing, in a large scale are so timing and cost consuming. One of methods which use for monitoring these properties and decrease the costs of sampling in large scale is interpolation. Interpolation has many methods and each one has a different accurate in various conditions. In current research three ordinary interpolation methods were used for interpolation some chemical properties of Khuzestan’s agricultural soils. These variables in this research were Total Nitrogen (TN), Absorbable Phosphorous (P), Absorbable Potassium (AK), Calcium Carbonate percent (CaCo₃%), Organic Carbon percent (OC%),  Electrical Conductivity (EC), and Soil Acidity (pH), which measured in 270 soil samples.
Due to the skewness and Kurtosis of these data, it was found they have not a normal distribution. In order to normalize the data, after deleting the outdated data, logarithm and Cox-box method were used.
 
The interpolation methods which used were kriging (OK), Radial Basic Functions (RBF), and Inverse Distance Weighted (IDW). Mean absolute error (MAE), mean bias error (MBE), and root mean square error (RMSE) were used for detecting the optimum method.
Examination of variographic results showed that the spatial structure (correlation ratio) of absorbable phosphorus (0.243) and absorbable potassium (0.159), strong, total nitrogen weak (measurement error 0.816) and the other parameters had a moderate spatial structure. Based on the results of this table, the ordinary kriging method with exponential model can be considered as the best and most accurate method (MAE = 0.01515, RMSE = 0.0890, MBE = 0.0006 and R2 = 0.912) for interpolation the total nitrogen.However, the best method for interpolation of organic carbon, absorbable phosphorus, absorbable potassium, calcium carbonate, acidity and electrical conductivity of soil are RBF, ordinary kriging (spherical model), ordinary kriging (spherical model), RBF, ordinary kriging (with exponential model) and RBF respectively.The results showed that the IDW method was not a suitable method for interpolating any of the parameters.
From the prepared maps, it can be clearly seen the non-uniformity of fertilization, amount of absorbable phosphorus in the southern parts of the study area is higher but amount of absorbable potassium in the northern and central parts of the study area has been more.While in the eastern and western part of the study area and in places where the pH is above 7.7, the amount of calcium carbonate in soils is at its highest level of 46 to 49 percent.
Preparing maps with appropriate accuracy by geostatistical methods for parameters that have good spatial dependence is a suitable method for monitoring and land management at the macro level.