نشریه منابع آب و توسعه
پیاپی 2 (بهمن 1392)

Estimation of lagoon water depths using satellite imagery plays an important role in monitoring water level for future planning in environmental protection. Although the application of these methods for lagoon bathymetry is relatively new, the methods are basically similar. The main purpose of this paper is to investigate the ability of hyperspectral satellite imagery for shallow water bathymetry. However, the best method, i.e., Lyzenga and Stumpf Rational Model, is employed and tested in this research. The algorithm is based on the ratios of transformed reflectance values in the visible bands, retrieving greater depths than previous algorithms and compensating for variable bottom type and albedo. This method requires a few numbers of parameters to be tuned and can be applied to low-albedo features. We have applied the proposed method to the hyperspectral image data obtained by Hyperion sensor of EO-1 satellite. This dataset covers a shallow water area around Qeshm Island, in south of Iran. The results were indicative of the usefulness of such image data and remote sensing techniques, especially for the areas which lack precise bathymetric information or for the purpose of monitoring application of seasonal depth variation.

Among the most important natural phenomena of the earth are wetlands that form in certain circumstances. Formation of wetlands is related to topographical, geological and geomorphological factors as well as hydrological and climatic characteristics of the regions. In Eastern Azerbaijan, there are numerous wetlands, a significant number of which are located in Hashtrood region. The most important wetlands in this region include Zulbyn, Yanyq, Bzvjyq, Khorshid,Sadtlv and QrkhBolakh. Topography and lithology (evaporation formation) are among the effective factors in shaping the wetlands. At present all wetlands except Zvalbyn and Sadtlv are filled with water throughout the year. Morphologic studies shows that the largest wetland is Bzvjyq with 100,000 square meters area and the smallest wetland is Sadtlv (10,000 square meters). Results indicated that there is an inverse relationship between pond area and the drainage basin area. Compactness coefficient indicated that maximum coefficient is related to Yanyq and Khorshid wetlands which is indicative of the extent of their basins. This is important in terms of maintaining water in wetlands.

Heavy metals in municipal and industrial wastewater can pollute surface water, sediment and soil. In order to evaluate the concentration of heavy metals (Zn, Cd, Pb) in Goharrood sediment and water, a project was designed and to this end, samples of water and sediment were collected. Coordinates of the sample points were determined by GPS (Global Positioning System). Moreover, in the sediment samples, the total amount of Zn, Pb and Cd were determined by atomic absorption spectorophotometer after extraction. The amount of metals, Ph, EC, TDS, SAR were determined in samples of water. Total Pb,Cd and Zn concentration was extracted by 4M HNO3.. Statistical assessments were carried out by SPSS. Results showed that water in all stations were not contaminated by cadmium. Moreover, Zn and Pb contamination were lower than toxic levels. Collected sediment samples were polluted by Pb and Zn but cadmium concentration was insignificant. Maximum concentration of pb (18.20 mg/kg) was observed in the eighth station and minimum concentration of pb (2.10 mg/ kg) in the twenty second station. Furthermore, maximum concentration of Zn (101/64 mg/kg) was observed in the fourteenth station and minimum concentration of Zn (37.80 mg/kg) in the twelfth one. In the last station, maximum concentration of Cd (0 /49 mg/kg) was observed.

Lake Urmia basin is one of Iran’s basins. In the last few years, due to natural and human factors, the lake's water level has declined and its surface area has reduced. As a result, the coastline and the surrounding area have undergone considerable changes. In eastern Azarbayjan province as in other areas of Iran, there are several wetlands few of which are located in south and eastern south. The main objective of this paper was to study morphological changes of wetlands. So, the lake level changes were investigated using Landsat satellite images (including TM and ETM sensors) for the years 2000 and 2010, and the lake's water level fluctuations were determined. Next, geomorphologic effects of the area, especially wetlands and their changes, were investigated based on satellite imagery. The results showed that the studied lake area has shrunk for more than 10 square kilometers, which have subsequently been added to the playas. The wetland areas in the region have significantly shrank and two lagoons (GareGeshlag and Yadegarloo) have dried up. The results also showed that this reduction had a great effect on the morphology of the region, especially on the reduction of the wetlands.

Change detection involves the application of multi-temporal datasets to quantitatively analyze the temporal effects of the phenomena. This study aimed to evaluate land cover/use changes of Solegon Wetland using Landsat TM satellite images. Two images over 11 years period (taken 1998, and 2009) were compared and geometric, atmospheric and topographic corrections were applied. Maximum likelihood and post-classification techniques were used to detect land use changes. The overall classification accuracy and Kappa coefficient for the produced maps were more than 0.72 and 79%, respectively ((1998, 0.91 & 83%) and (2009, (0.72 &83%)). The results showed that part of rangelands and agricultural lands dramatically changed in 2009 compared with 1998 and some areas changed to bare soil and the Solegan wetland shrink from190 to 69 hectares during this period. The findings of this study denoted that remote sensing data can provide appropriate information for specifying land use changes due to their repeatability, broad vision and digital format suitable for computer analysis. This approach will support adaptive management of wetlands such as Solegan.

Historical literature indicates that the older civilizations have been formed beside the rivers and wetlands and various values of the wetlands have always improved the quality of natural environments. Nowadays, most people, particularly those living around the wetlands, are to some extent aware of the values and functions of the wetlands, and the role they play in sustaining the indigenous communities. Parishan wetland is one of the most beautiful freshwater lakes with 43 km2 area. The wetland is in Kazerun, Fars Province and is the largest freshwater wetland in the country. It receives only very a small amount of water from feeder rivers and the whole lake/wetland is a protected area, as it is considered a globally significant wetland ecosystem. Parishan wetland in Fars Province is among the valuable and important ecosystems of Iran, which provides not only rich biodiversity but also significant socioeconomic services to the local population. The wetland is part of the “Arjan Parishan” protected area and is registered as an internationally important wetland in Ramsar Convention. It is considered a biosphere reserve by UNESCO. Currently, due to droughts, only 20% of the wetland has remained, hence the situation is very fragile. So, devising the management plan of Parishan wetland is necessary. The management plan is to balance individual and team efforts for the common objectives among which are conservation, sustainable utilization, restoration and development of Parishan wetlands. Therefore, in this study some strategies are presented to achieve these goals and finally, necessary projects to achieve these objectives are explained.

Identification of ecological or bioclimactic regions in different gepgraphical areas can help plannig of ecotourist attractions so that these areas can be used for recreation and leisure. Having a high potential for ecotourism attractions, Chaharmahal and Bakhtiari Province, attracts many tourists. One of these attractions known as Choghakhor wetland is located in the city of Boroujen. The aim of this study was to identify potential wetland ecotourism and eco comfort of Choghakhor using Baker's method. In this study, Baker method was used to determine the eco-comfort for months from 1996 to 2011. The results indicated that in April and May the amount of CP on cold nights and cool days and cold stress. In June, the amount of CP in the cool night air on a mild day. In July and August the CP is mild and humid. In July, it's hot and humid and unpleasant while in August it is tolerable. In September, CP is cool at night and mild and pleasant in days. In warm days and cool nights, CP is tolerable. In the month of October and December and November CP on cold nights and cold stress (November) is too cold. In October and December, the amount of CP is too cold. In October it is mild and pleasant, and in December it is cool. In Jan, Feb. and March, the amount of CP at nights is so cold and a little cold during the days.

Too many variables affect the evaporation rate of lakes’ surface water. Accordingly, to determine their effectiveness, laboratory investigations and the identification of these variables are of great importance in protecting these national assets. In this survey, the related researches carried out over the last half century are evaluated. Subsequently, in accordance with the prevailing climatic conditions of Iran, the suitable strategies for reducing surface evaporation are introduced. Next, the natural and human- caused damages to the country's water resources are analyzed, and guidelines are provided with regard to the environmental considerations, among which are spraying thin coatings of monolayers and floatation of inexpensive solid objects like Lightweight Concrete Blocks. To this end, a series of experimental investigations are in progress in order to achieve a cost-effective solution with no damage to the ecosystem.

The purpose of this study was to estimate the most important non-market values of the ZW. A survey questionnaire based on Single-bounded dichotomous choice contingent valuation approach was utilized in order to elicit Willingness to Pay (WTP) for the ZW conservation. The study was conducted in Kurdistan province in Iran. Three hundred and thirty respondents were willing to pay for conservation of the ZW. The mean WTP was estimated at RLs 275,010.7 annually per household. Considering the whole number of households in the study area which was 164,483 in 2012, the mean WTP for the study area was calculated to be RLs 45,234,593,192.25 annually. The relationships between various explanatory factors and WTP were discovered by applying the Logit model. ‘Bid’ and ‘age’ variables were statistically significant and had a negative effect on the respondents’ WTP. In addition, ‘income’, ‘membership in NGOs’ and ‘number of household’ variables were statistically significant and had a positive effect on WTP. The results can be used to build local and political support for conservation and sustainable use of the ZW and can convince policy makers and site managers to bring more financial support and better policy program to the ZW preservation.