نشریه محیط زیست طبیعی
سال شصت و ششم شماره 4 (زمستان 1392)

Internationally، one of the most important purposes to establish a national park is to protect a unique ecosystem with all its inclusive biota. Therefore، this will facilitate the management and protection of the neighboring lands. Unfortunately، this trend was reversed in Iranian national parks. During recent decades، the land cover changes in protected areas have led to the decrease of the remnant biodiversity in these areas. In this article، land use/cover change and development trend was studied by using satellite images in Khojeer and Sorkhe Hesar national parks between 1986، 2000 and 2010. The satellite images were corrected and they were classified in five classes. The surface areas of the classes have been determined separately and they were compared between each year. The results show that during the study period، both national parks appeared with land use change toward degradation. Khojeer national park faced more with decrease in range lands and Sorkhe Hesar National park expressed with human development، which was superior compared to the Khojeer.

This study was performed with objective land cover change prediction (forest، agriculture، residential and orchard) using logistic regression and Markov Chain in the GIS environment in east of Mazandaran province. Land cover change detected using satellite imageries belonging to the years 1987 and 2001. Transition potential modeling was conducted using a logistic regression. Seven variables (DEM، distance from residential، distance from agriculture، distance from forest، distance from river، distance from road، and qualitative variable) and 7 sub-models (forest to agriculture، forest to residential، forest to orchard، agriculture to residential، agriculture to orchard، orchard to residential، orchard to agriculture) were employed. Land cover change prediction conducted using Markov Chain and hard prediction for 2006. The accuracy assessment was determined using predicted map compared with actual map 2006. Finally، landcover change prediction done for 2013. Results showed that during the years 1987 to 2001، the large amount of forest and orchard have been reduced and، in contrast، agriculture and residential have been added. Null successes، hits، misses and false alarms were 89. 8%، 0. 1%، 9. 8% and 0. 3% respectively. Total error prediction model was 10. 12% which is indicative of acceptable model. Furthermore، the prediction results showed that forest and agriculture will be reduced and residential and orchard will be increased in 2013 compared with 2006.

A monotonic decline in species richness and diversity with increasing elevation has often been considered as a general pattern، but recent evidence suggests that the dominant pattern is hump-shaped or unimodal with maximum richness occurring at some mid-elevation point. This study was conducted in Kheyrud forest، Mazandaran province. The study area was divided into six elevation levels according to plant communities. Sampling was carried out in mid-spring at 163 random sampling points، which were located with a minimum distance of 250 m apart، as well as a minimum distance of 25 m from the edge of forest. We applied «unlimited radius point count» using «sit and wait» method to count observed and/or heard bird species from dawn until 10:00 am، lasting on average 10 minutes، and avoiding windy and rainy weathers. Our results revealed the existence of significant differences in richness and diversity between elevation classes. Also، we found a hump-shaped pattern of bird species richness and diversity against elevation، reaching the maximum at mid-elevation. These results highlight the importance of forest communities at mid-elevation in North of Alborz Mountain Range and suggest that silvicultural practices should be managed to conserve biodiversity at this elevation zone.

Diazinon is one of the highly consumed organophosphorous pesticides. It inhibits cholinesterase enzyme in animal tissues. Due to permanent residence in agricultural drainage channels، the swan mussel (Anodonta cygnea) can be considered as one of the most suitable indicators of such pollutants. At the present study، acethyle cholinesterase activity of A. cygnea was measured when exposed to various concentrations of diazinon (0، 1، 7، 15، 19، 23 mgL‐1) in different bivalve tissues، followed by comparison of short-term (first to fourth days) and long-term effects (7 to 21 days). The enzymatic activity was measured using the Elman''s method of ELISA assay. Our results indicated that there was a significant difference between cholinesterase activity levels in bivalve''s tissues at different concentrations of diazinon and exposure time. The specific activity of this enzyme in adductor muscle، digestive gland، foot muscle and gill were recorded as 27. 285، 16. 923، 2. 792 and 1. 914 nmol acethylethiocholine iodide hydrolyzed min-1mg‐1 protein، respectively. The adductor and foot muscle can be used as diazinon indicators after the exposure of A. cygnea to diazinon in environmental monitoring program. However، the gill among the other tissues، was the only one that was the appropriate tissue in determining the effects of low concentrations of diazinon (1 mg L‐1).

Due to the use of Secale montanum for different rangelands reclamation across the country، management of these ecosystems need to be aware of its ability to environmental stresses. This research investigated the effect of pollutant element of Cu and Pb on seed germination and growth of this species in laboratory. Therefore، the effect of five treatments (control، 50، 100، 150، 200ppm) of Pb (NO3) 2 and CuSo4 on the germination rate and percentage and growth of Secale montanum was studied in triplicate. Germination rate and percentage was calculated and growth rate was obtained by rootlet، shoot، and seedling length measuring. Allometric coefficient and seed vigor was measured too. The results of data analysis of variance and means comparison showed that Pb and Cu elements had no effect on germination rate and percentage but increasing of pb concentration caused to significant decrease in rootlet، shoot، and seedling length. Increasing of Cu element concentration decreased the seed vigor، allometric coefficient، rootlet، shoot، and seedling length significantly. Also، low concentrations of these elements were not a limiting factor for this speciesgrowth.

This study aimed to investigate the factors affecting intention of citizens toward participating in activities related to development and protection of green spaces in Tehran. The research was descriptive-correlation and survey method was used. The statistical population of this study consisted of all citizens in Tehran. Using proportional and stratified random sampling، 626 citizens were selected as research sample. Questionnaire was used to collect data. The validity of the questionnaire was confirmed by a panel of experts from Tehran Municipality and faculty members of agricultural extension and education in Tarbiat Modares University. A pilot test was conducted to determine the reliability of the questionnaire. Cronbach''s alpha was estimated between 0. 87-0. 91. The collected data was analyzed using SPSS software. Based on the research results، the intention for participation in protection and development of green space activities of 54. 1 percent of the citizens were at a high level. There were significant differences between the different regions regarding the participation of the citizens. In this regard، the citizens of semi-marginal areas have more intention toward participating in green space protection. There were positive and significant relationship between number of received seedlings، number of reference for getting seedlings in recent years، citizens'' perception of green functions، awareness of the destructive factors of green space، attitude towards investment in developing green and education of citizens، and protection and development of green space. Stepwise regression analysis showed that four variables included attitude towards investment in development and conservation of green space، citizens'' perception of green functions، number of received seedlings and education are effective on intention toward participation.

Without doubt is one important aspects of sustainable forest management the continuing forest regeneration. Identify and determine is effective dispersal and distribution pattern of regeneration patches in various types of forest and its evolution، in maintaining biodiversity in natural ecosystems. Purpose was chosen of Gorazbon district Kheyrod forest for study، all patches regeneration were located in its. was used the analysis landscape metric in GIS and FRAGSTATS. Based on survey results، total were identified numbers of regeneration patches 723 in various types. Maximum and minimum were observed distance between patches in this study between 260 and 54 meters، respectively. According to measured the metrics، distribution pattern and patches structure in types Fagetum – Carpintum، Fagetum – orientalis and Carpinento - Fagetum than other types is of distribution and better uniformity، and can be used as regeneration natural pattern considered for follow of natural processes and sustainability and forest resources continue.

In this study، effective criteria on process of tourism areas selection were collected due to macro planning of capable areas to tourism sample regions in Khorasan Razavi province. Then، their priority was carried out based on Delphi method. After determining the relative weights and criteria priorities، the map of capable areas to planning tourism sample regions was obtained at the province level. According to this research، 25 major criteria and 82 sub criteria were found from seven environmental criteria groups، tourism، physical- infrastructural، economic، cultural- social، design and also management. Cultural-Economic and management criteria group had the maximum and minimum numbers of sub criteria with 28 and five criteria، respectively. Delphi findings for the criteria groups show that in process of tourism areas selection، environment، physical-infrastructural، cultural-social، design، management and economic criteria groups presented priority 1 to 7، respectively. On basis of this study، for determination level of effectiveness about sub criteria in the tourism areas selection process، 8. 3% of sub criteria were detected in very high-influence class، 22. 6% in high-influence class، 35. 7% in medium-influence class، and 33. 4% in low-influence class. In addition، regarding to involve of eliminating indicators، the most priorities were assigned to attractions and tourist destinations، tourism and market demand، environmental hazards، sensitive habitat and also vegetation sub criteria، respectively.

In this paper the risk of heavy metals discharged from the acidic sludge leachate into groundwater in a landfill located in Fajr industrial area)Garmsar (has been assessed using IWEM software. Acidic sludge as one of the industrial hazardous wastes is produced during purification of used oil with Mienken) acidic (method. The concentrations of heavy metals) Cd، Ni، Co، pb، Zn، Mn، Cu (in the acidic sludge were determined and the discharge of these metals into groundwater was assessed by IWEM) using Monte Carlo analysis and simulating the parameters of case study for risk assessment (. Then، the best linear for the protection of the groundwater in landfill was recommended; which in this case was the NO Linear option. The low potential of groundwater pollution in the region was because of the deep location of groundwater level، low depth of the sludge in the landfill، dry climate and low amount of rainfall in the area، and soil type of the location) silt-loam(.

In the recent years، rapid growth of the world’s population and overutilization of fresh water resources have caused fresh water shortage crisis in the world. In spite of the agricultural activities in the Northern beaches of Iran and also severe decrease of the ground water level، it still has not taken any effective measures to desalinate Caspian Sea water in large scale. In this research، desalination of Caspian Sea water by Silica Nano-Particles with the diameter less than 50 nano meters for agricultural usage has been studied. In this study، by primary experiments the concentrations of the studied parameters including Electrical Conductivity (EC)، Sodium (Na)، Potassium (K)، Calcium (Ca)، Magnesium (Mg) and Turbidity of the sea water raw sample were measured. By useing of Jar Test، various dosages of Silica Nano- Particles and the wide ranges of pH were examined. The results show that the 0. 45 gr/lit of Silica Nano-Particles is the optimum dosage and pH=10 is the optimum pH for desalinating of Caspian Sea water. Meanwhile، the results revealed the extraordinary effect of Silica Nano-Particles on the studied parameters and has reduced their concentrations significantly so that the concentrations of Na، K which are the most important factors for water salinity، reached to zero.