نشریه محیط زیست طبیعی
سال شصت و پنجم شماره 3 (پاییز 1391)

In recent years, Wildlife habitat needs to meet critical requirment (water, food, cover and reproduction sites) on the one hand, and human needs to natural lands for developing agricultural, industrial and residential activities on the other hand, have lead to the serious human-wildlife conflicts. Attacks of wolves to human and livestock in Hamedan province is an example of these conflicts. Developing and implementing a consistent strategic management plan in agreement with socio-economic conditions, can be considered as an effective tool to reduce risk of conflicts in the area. In this study, we looked for the strengths and weaknesses as well as opportunities and threats to which environmental management of this province is facing and/or will be faced in future. Then we categorized, weighted and analyzed them, using SWOT analysis. Finally, we applied a quantitative strategic planning matrix (QSPM) to prepare an appropriate strategic management plan to remove or reduce the conflicts. Our result suggest three principal strategies including; (i) giving information and awareness to Indigenous communities, (ii) supporting environment-guards, equiping guard-stations, as well as monitoring and patrolling in the area, and (iii) collaboration between Environmental conservation office and related organizations of the province in order to developing and applying a consistent land management plan.

Heavy metals are very important from environmental consideration due to their toxicity and accumulative properties. The aim of this study is the evaluation of spatial distribution of Cr, Co and Ni in the surface soils of Hamadan province. For this purpose, the surface soil samples (0-20 cm) were collected using systematic random sampling method and the concentration of heavy metals and some of the soil parameters such as pH, EC, the percentage of organic matter, sand, clay and silt were analyzed. For interpolation and mapping the spatial distribution of heavy metals, the accuracy of Kriging methods and their models were compared by the Mean Absolute Error (MAE) values and Mean Bias Error (MBE), and the method with the lowest error was selected. Maps of chromium and nickel distribution were prepared by ordinary Kriging with a spherical model, and that of cobalt by disjanctive Kriging with exponential model. The western regions of Hamadan province had the highest concentration of chromium, cobalt and nickel. According to obtained maps, the regions with the highest concentrations of heavy metals corresponded to the igneous and metamorphic bedrocks. It seems that the geology is the main factor influencing the concentration of heavy metals in the soil.

Pesticides are one of the most pollutants in aquatic ecosystems. Monitoring of aquatic pollution with these compounds is very important. Therefore, health status of aquatic animals can be used as a bio-indicator for pollution monitoring in surface waters. Diazinon is an organophosphorous pesticide, which is found in the aquatic environment of Iran. The concern has arisen over the ability of this compound to affect the health of fish in recent years. In this study, the effects of exposure to sub-lethal concentrations of diazinon on some biochemical parameters of rainbow trout, Oncorhynchus mykiss were examined after 7, 14 and 28 days. Acetylcholinesterase (ACEh) activity and the levels of total protein, albumin as well as globulin in plasma were significantly reduced at 0.1 and 0.2 mg/L concentrations tested (p<0.05). Creatine kinase (CK) activity was significantly lower in 0.1 mg/L diazinon group at 14th and 28th sampling periods, whereas its activity significantly increased in fishes exposed to 0.2 mg/L diazinon only on 7th day (p<0.05). Aspartate aminotransferase (AST), alanine aminotransferase (ALT) activities and glucose levels in diazinon treated groups were significantly higher than the controlled group at experimental periods (p<0.05). Alkaline phosphatase (ALP) activity only significantly increased after 14 days in both diazinon treatments (p<0.05). The hypertrophy of hepatocytes, the vacuolization of cell cytoplasm, as well as hepatocyte cloudy swelling were observed in liver tissue of fish exposed to both concentrations of diazinon. Therefore, measurement of biochemical markers and liver tissue pathology studies are proposed as simple and suitable tools for assessing pesticide effects on fish.

Rice husk is as an organic solid waste material that has high adsorbing capacity in removal of heavy metal ions from wastewater, and can be very effective in treating industrial aqueous solutions that are important sources of water and soil pollution. In this study, the removal of Zn(II) and Cr(VI) ions from aqueous solutions using rice husk was investigated. The investigated parameters included acidity, initial concentrations of ions in aqueous solution, contact time, temperature and the amount of adsorbent matter used for treatment. With increasing pH of the solution, the adsorption of zinc and chromium ions by rice husk were increased and decreased, respectively. The maximum adsorption was occurred in pH 7 and 2. Moreover, with increasing initial concentration of metals, the removal efficiencies of zinc and chromium were decreased. While, with increasing the contact time, the removal efficiencies were increased and reached an equilibrium after 2 and 3 hours for zinc and chromium, respectively. The metal adsorption is also dependent on the reaction temperature, so that by increasing temperature the percentage of adsorption was increased. With increasing the amount of husk rice to the solution, the percentages of adsorption of zinc and chromuim were increased. Rice husk showed to be a proper absorbent for the removal of Zn (II) and Cr (VI) from aqueous solutions.

Spatial pattern of trees is an important characteristic of plant communities. Generating hypotheses relating to the structure of ecological communities is the aim of spatial pattern recognition. Stands spatial patterns are measured and mapped by measuring tree locations in the stand and entering each coordinates into analytical frameworks. The spatial pattern of plant populations observed at any point in time is the product of many processes in the past such as seed dispersal, growth, mortality, soil topography, microclimate, or disturbances. The aim of this study is to investigate on spatial pattern of three species Oak (Quercus. libani, Q. brantii and Q. infectoria) in Chenare forest at Marivan city in Kurdistan province. For this purpose, T-square distance sampling method was used. A grid of 100 m×100 m was applied and then 30 sample plots were established. The grid intersections were applied as the center of sample plots and the beginning of distance sampling techniques. Hopkins, T-square and Johnson and Zimmer indices were used to analyze the spatial pattern. All of the indicators showed a random pattern for Oak species. Such spatial information allows to natural resource managers to make better-informed decisions and increase the potential for enhanced natural resource utilization.

Nowadays green house gases such as carbon have the most effect on global climate changes that can be decreased by plant and soil carbon sequestration of rangelands. Livestock grazing has high potential to decrease or increase carbon storage. So this research investigated the effects of enclosure on plant carbon storage in rangeland of enclosure (Shah Tappeh-Chah Mahmood) and no enclosure (Chiro) with dominant spices of Artemisia aucheri in Semnan province. Plant sampling was done in key areas by random-systematic method with 4 transects of 100m and 40 plots of 1‎×1m2. Then plant and soil parameters evaluated in each plot and carbon determined by Ash method. The data analyzed by SPSS v.16 software. The result showed that there is a significant difference between plant cover, gravel, bare soil percentages and also aerial and underground biomass and litter of Artemisia aucheri in two regions. The total biomass in enclosure rangeland with 11467/3 kg/ha was more than no enclosure rangeland. Root coefficient alteration (enclosure: 12/67% and no enclosure: 12/3%) was more than the other organs and there was no significant differences between coefficient alteration of organs and litter of Artemisia aucheri in two regions. The result also showed that there is a significant differences between carbon sequestration of Artemisia aucheri organs (level: 1%) and litter (level: 5%) in two study areas. Regarding to the effect of enclosure on plant cover and carbon sequestration increasing, it's suggested to protect plant cover in grazing management programs.

The purpose of this study is environmental risk assessment of pipelines in case study conducted in the 9th National Gas Pipeline in Lorestan province (Iran). The study employed the indexing method for investigating the risk through the Muhlbauer method. Geographic Information System is also used to develop the maps corresponding to the environmental risks and to map the relative risk scores and also to delineate the current status of environmental resources in the study area. The different sub-indices were compared and prioritized using a hierarchical analysis. Among the layers under investigation, the land use layer gained the highest score. Accordingly, the land use layer proved to have more weight, compared to other layers, in calculating pipeline risk. Among the obtained scores, the sub-index of third-party damage scored lower than the others, indicating more risks. The sub-index of corrosion scored higher, indicating fewer risks. Indexing System is a comprehensive method. This method includes all of qualifications and in this study earned appropriate results. In the future study it is proposed the by selecting suitable sections the effects of gas pipelines in limit of microclimate.

One of the factors and tools necessary in managing roadside is rules and regulations without which, the area will face serious challenges in terms of the environment. Recognizing rules of roadside was investigated in the current research, since some perturbations and irregularities related to the ecosystem of roadside are the results of rules and regulations and also complex damages appeared in privacy of the roads due to incomprehensive rules with several executives. So in this research, qualitative research method and library studies are used in order to investigate and recognize legal rights present in privacy of roads. Also using targeted sampling method, 36 members of five villages were investigated in 5-person groups who were the residents of area near the road of Kouhikheyl to Behenmir. The total of the data were analyzed. The results showed that diversity of legislations, imposing legislations by various executives, lack of defining management system and exploiting privacy roadside vegetation, weakness of laws from the environment point of view are the most important challenges in the way of managing the mentioned area. Also sheep grazing without authorization and 8-percent portion of privacy road vegetation in providing local livestock forages indicate lack of supervision of organizations which finally leads to unlimited exploitation in roadside ecosystem.

Unplanned urban development imposes significant pressure on land resources and land use structures and brings about many negative socio-economic and environmental consequences. Therefore, comprehensive studies should be applied to support urban land use management in the world and especially in developing countries. In Iran, like many other developing countries, urban development is fast and often unharnessed. Tehran province is the main focus of urban sprawl, in which strong economic state and allocation of facilities and infrastructures encourage mass migration of people and cause unplanned construction and changes in spatial structure of the region. In this study, an integrated approach towards urban land suitability assessment in Tehran province including social – economic and ecological aspects has been implemented. The employed method and the developed model can be considered as an efficient sample of achieving sustainable urban development and regulating the physical development in Iran. In this research, a Weighted Linear Combination Method was conducted in a Geographical Information System considering 15 criteria, including social–economic and ecological factors. For weighting the criteria, the Analytic Hierarchy Process was used including opinions of ten experts. At the end, a land suitability map was produced showing suitable area for urban development. These areas include six arenas with suitable extent and desirable suitability in southern part of the province that can be used by urban planners and spatial decision makers. As the results are systematic and reproducible, they can be regarded as means of collaboration and consensus making among urban developers and decision makers.

Artemia, a small crustacean, with high commercial value is a valuable model organism for researchers. This creature by tolerating extreme range of different environmental conditions is dispersed to more than 600 and 18 sites over the world and Iran, respectively. Tashk Lake is one the natural parthenogenetic Artemia habitat in Iran. Due to occurrence of an unknown bisexual Artemia in Tashk Lake, the species of this un-endemic Artemia was researched. In this regard, four different molecular markers as Na/K ATP-ase, 12S-16S by PCR-RFLP technique and COI and HSP26 by sequencing and subsequent Genbank data were studied. The conducted analyses as long as emphasizing to ability of molecular techniques for identifying unknown species characterized the new population as A. franciscana. These analyses also revealed a molecular diversity between the sequenced genes with the data found in the Genbank.