Journal of Environmental Studies
Year:2008 | Volume:34 | Issue:46|Papers Count:18

Identification of basic ecological resources such as flora and vegetation is one of the most important activities in the protected areas. These researches have especial importance in the arid regions due to habitat sensibility. The large part of Iran possess arid and semiarid climate and coastline of Persian Gulf have noticeable importance. Mond as a protected area with 53000 ha is situated in S. W Bushehr. Mond is a conspicuous symbol of saline habitat of Persian Gulf and is a biological museum that represent diverse spectrum of habitat and plant species and have important ecological values. Totally 142 plant species from 114 genera and 46 families were determined in the area. Poaceae, Asteraceae and Chenopodiaceae have 23, 17 and 14 species and are the largest families in the area. In case of life form, therophytes have higher proportion which followed by phanerophytes and chamaephytes. Chorologically, 24.4% of plants have monoregional distribution, of which Saharo-Sindian plants have the highest proportion. The remained percent of plants are related to more than one phytogeographical region ofwhich Irano-Turanian-Saharo-Sindian plants have the highest proportions. Plant habitats are including: mangrove, riverside, wetland, sand dune, humid, island and abandoned. Tahmadon, Omolgorm and Nakhilo represent island habitats that have high ecological and conservational values. 

Natural forests of Tehran province belong to Irano-Turanian vegetation zone. Trees and shrubs of mountain flora of Irano-Turanian zone generally grow in a scattered manner, but in some places, they grow thickly and organize some forest stands or bush woods (Clumped pattern). These stands are special parts of Irano-Turanian zone and they are The habitat of numerous animals and birds. In fact, we should know these stands as special and valuable ecosystems. In this research, we tried to recognize and introduce these ecosystems in Tehran province. So we recognized and introduced more than 70 stands. Forests of Tehran province were divided into 3 types: 1. Conifer stands 2. Tree hardwood stands 3. Shrub hardwood stands; and data were analyzed on the base of this division. In the first group: “Junipers polVycarpus", in the second group "Pistachios mutica" and in the third group "Cotoneaster spp." and "Amygdales licorices" are dominant tree or shrub species. Also, there are some sites with other dominant species: Ulmus sp., Malus orientalis, Salix spp., Populus nigra, Betula pendula, Amygdalus scoparia, Rhus coriaria, Berber is spp. and Rosa canina. The area is variable between 0.5 and 400 ha. Also, in this study, we presented the tree and shrub flora of Tehran province that includes more than 110 species; 37% of the species belong to “Rosaceae" family. As a result, Juniperus polycarpus, Amygdalus lycioides, Berberis spp., Rosa spp., Pistacia mutica, Cotoneaster spp., Rhamnus pallassii , Cerasus microcarpa, Amygdales scoparia, Celtis caucasica ,Rhus coriaria and Salix spp. are the main native tree or shrub species of Tehran province. Most species of Tehran province belong to Irano-Turanian biogeographic zone but just in 340 ha, in the north-eastern of the province, we can see hyrcanian zone species such as Juniperus communis and Querqus macranthera. 

Khanikan Forest is located in South of Nowshahr and Chalous cities. This Forest was quantitatively analyzed. In order to determine forest types and spatial patterns of tree and shrub forest species, sixty plots (400 m2) were taken by a systematic random sample method. Result showed that the number of plots in North, South, East, West, North west, North east, South west, and South east aspects were %18.6, %3.38, %10.1, %11.8, %18.6, %23.72, %8.4, and %54, respectively. On the basis of IVI (Importance Value Index), dominant forest type of study area was characterized Carpinus betulus (IVI=152.80) and Parrotia persica (IVI=85.34). This forest types were observed in whole of aspects. Spatial patterns classification of species was distributed by clumped and random forest type characteristics.

Landslides are common in mountainous regions and are triggered by heavy rains and earthquakes, and often occur in association with human disturbances (e.g., roads and clearing of forest). Regional landslide susceptibility assessments pose complex problems. To solve these problems, numerous approaches, such as fuzzy logic, geotechnical engineering approach, geomorphologic approach and statistical analysis have been employed. However, determining probability of future landslide events is difficult because so many factors can contribute to the cause of a landslide or ground failure. They are very important in Planning and Management of forestry plans such as reforestation, harvesting, forest road construction and etc. Use of the statistical approach to determine landslide occurrence in Guilan forests is the main purpose of the present study. For this purpose, the study includes 37 landslides in Guilan’s forests and measured 23 effective quality and quantity factors of them. Then these were analyzed by ARC-GIS software and combined different map. Finally, landslide in formation and harvesting analyzed with discriminate analysis by stepwise method. Our regional analysis further substantiates that slope, aspect, road construction and harvesting, distance of failure, depth of rooting and soil properties effect in discriminate function of landslide. Therefore, they should be useful in regional planning, watershed analysis and timber harvest planning. For site-specific land management practices, field surveys are needed to evaluate the accuracy of them and as well other factors affecting local slope stability. 

Species diversity is one of complex biological concept. The reason of change in species diversity and control mechanism of this change is one of ecological salient questions. Conservation of biodiversity is final goal of natural resources management. In this research, species diversity has been analyzed in important Kurdistan's Kouhsalan habitat. On cluster sampling method, 82 plot were obtained. Clustering Analysis method was used to determine ecological species groups. Species diversity was calculated using Shannon-Wiener index, and relationship between Species diversity and soil surface cover investigated by regression analysis. Duncan's test was used to comparison of means. In this habitat, 224 species were recorded. On Clustering analysis, three groups with indicator species such as Quercus brantii, Hordeum bulbosum and Prangos ferulaceae were obtained. Shannon- Wiener index value for three groups and total area calculated 1.98, 1.95, 1.50, and 1.85, respectively. In groups and total area, linear positive model was significant between species diversity with total plant cover and herbaceous plant cover. In The first group and the third group, linear negative and positive model observed between species diversity with woody plant cover, respectively. Relationship between Species diversity and other factors was not significant. Linear positive model between species diversity with plant cover is an important guide for ecosystem management. Planning and projects should let it be so that conserves the vegetation cover, species diversity and natural ecosystem.

The damages due to Dwarf Mistletoes to the industrial forests encouraged the scientists to evaluate the infection intensity and illustrate the spatial distribution of mistletoes for forest management, wild life and biodiversity conservation. There are two current systems to evaluate infection intensity wich are easier, cheaper, more efficient and authoritative than others in all over the world, namely DMR and BVR. For investigation on mistletoe infection in Noor Forest Park and comparison of these two procedures, 30 sample plots with an area of 0.1 ha were selected. Since 94% of infected individuals in plots were Iron Wood trees (Parrotia persica), therefore only Iron Wood trees were evaluated. In total, 243 trees of 329 infected Iron Woods were selected randomly and analyzed. Results showed that 67% of trees had similar rate with these two systems and 31% had more DMR. Totally, the implementation procedures of DMR and accuracy of evaluation seemed better than BVR. Therefore DMR system can be used in studies of stands with high rate infection to determine the impact of mistletoe on forest ecosystem, stand structure, forest growth and production and even effect on infected individual productivity. Moreover, the results of infection survey in three parts of the crown showed that infection intensity on upper part of trees was more than the middle and lower parts respectively, which is because of the relationship of mistletoe seed dispersal to sitting, nesting and roosting sites of the birds that eating mistletoe berries. 

Carbon is the most important greenhouse element which sequestrates by photosynthesis procedure and is the easiest and cheapest way of decreasing atmospheric gas level. The vegetation cover that has woody texture is more capable for carbon sequestration. The most plant species of arid rangelands are the shrub growth forms. The purpose of this research was to assess carbon sequestration potential for dominant shrub species of arid rangelands in Garehbeygon area. After determination of key area, the percentage cover of three important shrub species Heliantemum lippii, Dendrostellera lessertii and Artemisia sieberi were measured. On the basis of statistical method for determining sampling number, 92 plants of H. lippii and 98 plants of each of D. lessertii and A. sieberi were chosen by random. The shoot (leaves, stems and branches) and root parts were transferred to laboratory for calculation of carbon sequestration factor of each plant parts by inflammation method The statistical results showed that the carbon sequestration by three plant species were significantly different (P<1%) and A. sieberi has the most potential of carbon sequestration in the region. The carbon sequestrations of the four parts of the plants (leaves, branch, stem and root) in the 3 studied species were significantly different (P<1%) with the stems holding the highest record of carbon sequestration and the leaves with the least. 

The algae of GarGar river (one of branches of Karoon River) which were investigated in samples collected from habitats (epilithic, epiphytic, epipelic) at eleven station between December 2004 and September 2005. This river receive types of sewage such as municipal wastewater, agriculture and aquaculture wastewater The flora consisted of 5 class and 24 genera belonging to the Bacillariophycea (12genera), Cyanophycea (6genera), Chlorophycea (10genera), Xanthophycea (1genera), Dinophycea (1genera). The Bacillariophycea was the dominant class and nitzschia was the most frequent genera in the epilitic substrate. The Cyaophycea was the dominant class and phormidium was the most frequent genera in the epiphytic substrate. The Bacillariophycea was the dominant from of algal flora. nitzschia, spirogyra, phormidium were the most frequent genera in the algal community. While the maximum density of the epilitic community was 282390 cell/cm2 in August and epiphytic community was 167435 cell/cm2 September. Results showed that the Algal growth is dependent on nutrienta, high temperature and slow velocity of river. The algal increased considerably from August until September. Thus, use of Algal communities is useful indicative for monitoring and assess changes in the water quality, generally changes due to anthropogenic causes (e.g. nutrients). 

This study was conducted to determine physiological and morphological variation of strains of the ectomycorrhizal fungus Hebeloma cylindrosporum associated with Pinus pinaster and its consequence on the symbiotic processes in coastal forests adjacent to Bordeaux, south west France, from 2003-2005. Mycelial cultures were conducted in the laboratory on a rich medium (YMG). Diploid fungal strains from the field as well as hybrid strains, originating from laboratory crosses between haploid isolates, were compared for growth rate at 12oC and 22oC. At 12oC there were significant differences between strains collected in coastal forests with the other strains. Metabolic abilities and growth rates were also investigated for mutant fungal strains that had incorporated in their genome a T-DNA from the phytophatogenic bacterium Agrobacterium tumefaciens. The data indicates that mutations induced by T-DNAs result in phenotypes that could affect symbiotic processes. The possible application of these findings in cultivation of trees in non productive coastal lands is discussed. 

Every year a large number of migratory wintering water birds, rest in the wetlands situated in the Northern provinces of Iran. The wetlands are very important ecosystems for these creatures. Due to ecological importance of water birds, the results of this study (the birds’ populations and their changes) are helpful to monitor them and are especially important to manage the wetlands. In this study, 38 wetlands consist of the Caspian coast along all the 3 provinces, 17 wetlands in Gilan, 7 in Mazandaran and 13 in Golestan have been studied. According to the results of the water bird censuses, in the mid-winters of 2000 to 2004 (5 years), which have been utilized in this study, totally a mean number of almost 1507000 water birds (115 species) have annually wintered in the wetlands. According to these censuses, the populations mainly consist of geese, swans and ducks (52%) and rails, gallinules and coots (32%). The most abundant species were common coot (mean pop. of 479835); common teal (mean pop. of 254658) and mallard (mean pop. of 133187) respectively. Mazandaran has shown the highest mean populations and the top number of species during these 5 years. The largest number of water birds was recorded in Mazandaran with the minimum species' diversity in 2004. In the same year, the highest number of species belongs to Gilan. Golestan has got the highest species' diversity. Among the wetland areas, Gomishan and Anzali wetlands have the highest score of water bird criteria (23 points). 

Birds constitute the important elements of most ecosystems of the world. The objective of this study was to survey and identify birds of Boujagh National Park. For this reason the Park divided into 7 parts and during 24 months, between autumn 1383 and late summer of 1385, the park has been surveyed. The results show that 234 species have been identified (about %46.4 of all bird species throughout Iran). The lowest number of birds were 19 species, while the most diverse orders were Passerine and shore birds mainly Charadriiforms, and the most diverse family were Anatidae and Scolopacidae.4 orders and 17 family with one species showed the lowest diversity and in between them 12 species mentioned in IUCN red data Book, of which 6 species were Vulnerable and 6 others were threatened. 31 species identified for the first time in the area. As the bird's fauna in Boujagh is very diverse, therefore deserve the highest considerations.

A study was conducted to determine habitat suitability of Goitred Gazelle (Gazella subgutturosa) in Kalmand-Bahadoran Protected Area during four seasons of year 2003-2004. The geographic position of dispersal points of gazelle herds was recorded with Global Position System. The data were transmitted into attributed tables in Arc view Software and their layers were created. The maps of slope, altitude, plant types, vegetation cover, soil types, water sources, roads, villages and farms were provided for gazelle habitat in study area and were digitized. These maps were analyzed with the layers of gazelle observations in the GIS software (Idrisi) and the habitat suitability maps of species were prepared. Chi-square tests showed the relationships between these environmental factors and gazelles dispersal were significant. Also the results of this study showed that in all seasons, gazelles showed high tendency to the adjacent farms. In Kalmand-Bahadoran Protected Area the gazelle habitats had the following suitability percentage; High 11%, Medium 40.3% and Low 48.7%. 

All of life form has own special worth. Although some taxa have been known less in compare to others, it is important to notice that extinction of them has undesirable ecological effects. Small vertebrates like rodents and lizards are noticeable examples. Iran in southwest of Asia with peculiar geographical conditions and diversity of habitats contains more than 200 reptile species which ecological value of them is unknown. Qum province is located in central plateau of Iran with 11238 km2 total area. Due to particular geographical and climatically conditions of this area, it has rich Biodiversity. Present investigation has been conducted to study habitat, substrate type, feeding, conservation and distribution of lizards in Qum province during January 2006 to now. Our results have been revealed that 20 lizard’s species belong to 13 genera and 5 families are found in the area. Agamid lizards with seven species have the highest species diversity. Also we have found that high ranges of habitats with different substrate type are inhibited by lizard’s species. Number of species in desert regions in compare to other part of the area is considerable. The conservation status of lizards is known and need more study. 

In this study, age and growth for two populations of Shemaya, Chalcalburnus chalcoides, in Haraz and Shirud rivers were investigated from April to June 2006. 704 fish specimens were collected using a Cast-net. The maximum length and weight in a 5- year old female observed were 251 mm and 96 gr, respectively. The most abundant age groups were 2+ and 3+ years for male and female respectively. While male of Shirud populations were heavier and longer on average in younger ages (ANCOVA, P£0.05), differences in female were not significant (ANCOVA, p³0.05). Female of Haraz population had isometric growth while positive allometry was observed in the fish population of Shirud. The Von Bertalanffy growth parameters were: (Haraz population: Lt=[405.9 (1-e-0.1(t+1.54))] for male and (Lt=[442.6 (1-e-0.1 (t+1.43))] for female), (Shirud population: Lt=[359.5 (1-e-0.145 (t+1.002))] for male and (Lt=[446.7 (1-e-0.1 (t+1.6))] for female). In the two populations, Female had higher L¥, while K value for males was relatively higher in the two rivers. 

Security building Processes after World War II, were under the influence of realistic thoughts. This was considered a reaction to idealistic and institutional approaches. Critical school attempted to criticize classical and structural realism. New security theoreticians emphasize on extended subjects and diverse threats and believe it to be beyond the competition of countries. They believe that subjects like global warming, ozone penetration and the other environmental problems are among future threats for mankind which make countries to encounter new common threats. Paradigm changes in international relationships terminate in a developed concept of security including environmental threats. Security-making processes are determined according to the threats; if threatening parameters are changed, new problem-solving processes must be taken in to the consideration. The first sign of environmental security threats may be defined as the limitation in use of natural resources. Nowadays global changes in atmospheric chemical composition, biodiversity and natural cycles are occurring faster than any time in the history of human beings. Accordingly, critical school theoreticians search for the true place of human health and survival within the security-making priorities. Fast rate of economic growth with no environmental consideration, the crisis of nonrenewable resources and local conflicts are among the most significant threats indicated by such theoreticians. The crisis of social identity caused by phenomena like seeking refuge, emigration and urban sprawling which basically have their roots in environmental deterioration has become a major concern in achieving sustainable global security. Lack of economical resources [as a consequence of environmental deterioration] may be introduced as one of the major causes in formation of social movements in the critical school. Critical school theoreticians attempt to create new definitions of security. Highlighting the new mutual threats, they try to provide the required infrastructure for achieving the global security through all the aspects.