مجله پژوهش و فناوری محیط زیست
پیاپی 5 (پاییز و زمستان 1397)

Indeed, protected areas, national parks and biosphere reserves in general, are the natural heritage of each country. Therefore, knowledge of their changes plays an essential role in management of these areas. Remote sensing is one of the most advanced and effective technology for monitoring environmental changes and resource management. The purpose of this research is to detect the land use /cover changes in Bojagh National Park in Guilan province during 2000-2017. For this purpose, the images of ETM+ sensor from the landsat 7 were taken in the year 2000 and the images of OLI sensor from the landsat 8 were taken in the year 2017. After applying the necessary preprocessing on the images, the training points were selected for each user class in sufficient number and with appropriate processing then, the land use / cover map was produced using the supervised classification method with maximum likelihood algorithm. Using the Overall accuracy test and Kappa coefficients, accuracy of the produced maps was determined. The results of the study indicated that the areas of the sea, grassland and the areas of the waterbody parts has decreased and the areas of the agricultural, marshland, man-made, woody and bare lands users show an increase during the study period.

Stilling basins are one of the most common structures for energy depreciation of flow with high velocity that among different sections and types of these basins, diverging stilling basins have better hydraulic performance and lower constructional costs. In this research, numerical modeling capability of diverging hydraulic jump on the reverse slope was investigated using Flow3D software. Experimental model data was used at divergence angles of 5 and 10 degrees in diverging angels of 1.3, 2.35, 3.2, 4.57 degrees in addition to classic hydraulic jump. The outputs of simulation model in comparison with the results of experimental data indicated that the model shows the amount of water surface profiles, jump length and maximum velocity in depth with good accuracy. The results showed that the mean relative error of water depth obtained from numerical model and measured values is about 15 percent. The velocity profiles were also in good agreement with the measured data.

Geomorphic changes of low-coastal areas, such as wetlands, estuaries and beaches depend heavily on the balance between input sediment from the basin or the sea and the outflow sediment with erosion source arising from wind waves and tidal flows. In this research, the flow and sediment pattern were investigated using MIKE21 model in the Sefidrud River and how the influence of flow pattern, sediment transport and sea water level changes on evolution of the delta and coastline were studied by landsat. The factors such as flow and sediment load of the river, sea level, wind and wave pattern are the most important factors which affect these changes. This study can provide a properly field for a right management in order to the region’s sustainable development, adequate knowledge of the Sefid-Roud hydrodynamic and sediment situation in estuary area, as well as taking the necessary measures to prevent damages caused by the Caspian Sea’s long-term fluctuations in the Sefid-Roud’s deltaic region.

Nowadays, environmental hazards that originated from inappropriate management of waste are one of the main problems of the country. Therefore, the development of waste management system and new and advanced technologies entry is necessary. Waste disposal by incinerator is an effective method. Unlike landfill, the use of incineration does not require long-term care and there is the possibility of energy extraction. One of the main disadvantages of this method is emission of air pollutants from the stuck of incinerators and management of the residual wastes such as ash. Therefore, selecting the best place for construction of the municipal waste incineration power plant will increase its benefits, reduce costs and eliminate community dissatisfaction by identifying and considering the involved and effective factors such as environmental, economic and social factors. In this paper, literature reviewes, searching for valid universal guidelines and the related articles in databases were used to introduce and compare the criteria mentioned for locating the municipal waste incineration power plant as one of the most important steps in designing a comprehensive waste management system.

The purpose of this paper is recognizing the potential of the bioclimatic comfort, ease of outdoors and tourism of this region in months of the year which is operated as a part of a research project with the aim of using the site of Booye- Amlash and increasing its economic efficiency. In this paper the residents comfort or lack of comfort is evaluated using statistic information gathered in Espily station in a 20 months’ period during the years 1991 to 2011, according to the models and bioclimatic indicators such as Evans method, baker method (CP), effective temperature method (ET) and Olgi method. The Results of this paper considering environmental conditions indicate that October, May, June, July, Agust and September are the best times for visitors entery the studying area that the comfort conditions are almost available.

Nowadays, there is an increasing need to develop high-yield, low cost, nontoxic, and eco-friendly procedures for synthesis of metallic nanoparticles. Therefore, the green synthesis methods become customary for synthesis of nanoparticles. Among metallic nanoparticles, nanosilver has developed because of its therapeutic properties. So in this paper, polysaccharide, tollens and biological green methods were investigated. In polysaccharide and tollens methods, starch and β-D glucose were used as a satabilizer and reducer respectively. In biological method biomass and cell filtrate of the Fusarium oxysporum fungus were used for the synthesis of nanoparticles. SEM images and UV-visible absorbtion spectra of these procedures showed that the polysaccharide method produced smaller silver nanoparticles wih high productivity. The changes of NADH-dependant nitrate reductase enzyme activity was evaluated in growh duration by colorometric Harely method due to importance of this enzyme in extracellular synthesis of silver nanoparticles. Results showed that the changes of dry cell mass impact on the enzyme activity.

One of the important aspects of nanotechnology application is expanding sustainable and eco-friendly procedures for synthesis of metallic nanoparticles. Therefore, the green synthesis methods become customary for synthesis of nanoparticles. In this research, green polysaccharide methods, modified polysaccharide, tollens and microbial methods were investigated. In polysaccharide and tollens methods, starch and β-D glucose were used as a satabilizer and reducer respectively. In biological method biomass and cell filtrate of the Fusarium oxysporum fungus were used for synthesis of nanoparticles. SEM images and UV-visible absorbtion spectra of these procedures showed that the polysaccharide method produced smaller silver nanoparticles (20 nm), more resistance (2 months) and higher efficiency. Also, TEM imageindicated that the shapes of these particles are spherical.