Iranian Journal of Applied Ecology

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Effective river ecosystem management requires that the existing hydrologic regime be characterized in terms of the natural hydrologic regime and the degree to which the human-altered regime differs from natural conditions. This is known as Range of Variation Approach (RVA) and can be used for variation of stream flow, range of variation and appraisal of dam impacts on riparian zones. In this paper, we used 31 hydrologic parameters, classified into five groups, monthly flow indices, extreme flow indices, timing indices, high-flow and low-flow indices, and rate of change, to assess hydrologic regime alteration in downstream of Karkheh dam. For this, purpose the hydrologic parameters of Pay-Pol hydrometric station have been taken. into consideration. As the Riparian ecosystems are highly dependent on and sensitive to variation in the hydrological cycle, the focus of this study was the 50-meter buffer of the Karkheh River. To examine the impacts caused by the variation of hydrologic regime, we tested if this variation and 8 different landscape metrics in the study area are correlated. The results showed that variation of hydrologic regime had a significant impact on the landscape structure of riparian zone in Karkheh downstream and caused isolation in landscape pattern of the woodland cover. Therefore, landscape structure in Karkheh downstream is highly correlated to hydrologic processes of upstream of the river. It can be concluded that an effective water management strategy is keeping safe the ecological condition and integrity of the riparian zone of Karkheh. This happens when all the hydrologic parameters are in the natural range of variation as they were before dam construction.

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The relationship between plant species and environmental factors has always been a central issue in plant ecology. With rising power of statistical techniques, geo-statistics and geographic information systems (GIS), the development of predictive habitat distribution models of organisms has rapidly increased in ecology. This study aimed to evaluate the ability of Logistic Regression Tree model to create potential habitat map of Astragalus verus. This species produces Tragacanth and has economic value. A stratified- random sampling was applied to 100 sites (50 presence- 50 absence) of given species, and produced environmental and edaphic factors maps by using Kriging and Inverse Distance Weighting methods in the ArcGIS software for the whole study area. Relationships between species occurrence and environmental factors were determined by Logistic Regression Tree model and extended to the whole study area. The results indicated species occurrence has strong correlation with environmental factors such as mean daily temperature and clay, EC and organic carbon content of the soil. Species occurrence showed direct relationship with mean daily temperature and clay and organic carbon, and inverse relationship with EC. Model accuracy was evaluated both by Cohen’s kappa statistics (κ ) and by area under Receiver Operating Characteristics curve based on independent test data set. Their values (kappa=0.9, Auc of ROC=0.96) indicated the high power of LRT to create potential habitat map on local scales. This model, therefore, can be applied to recognize potential sites for rangeland reclamation projects.

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Development of roads through protected areas and ecological sensitive regions can have catastrophic effects on wildlife. In Iran, road construction in sensitive habitats and protected areas has been expanding during the past decades. This study focuses on the ecological impacts of Isfahan’s west ringway, which passes through Ghamishloo wildlife refuge, I.U.C.N category IV, in Isfahan Province. The key affected species of the study area goitered gazelle (Gazella subgutturosa subgutterosa), was considered for impact analysis. We used HEP (Habitat Evaluation Procedure) as a habitat-based impact assessment methodology which considers habitat quality and quantity. Habitat quality was measured as habitat suitability index for the species. By literature review and field observations (293 presence points), five effective variables in habitat suitability including vegetation cover, slope, elevation, distance to water and distance to road were identified, and habitat units (HUs) were derived from multiplying the HSI for goitered gazelle by the species habitat area at two times (before and after road construction). The results showed that due to the presence of the ringway, 7710 HUs for goitered gazelle have been lost. In addition, we used landscape ecology approach for quantifying landscape pattern change due to road construction and landscape metrics including NP (Number of Patches), MNN (Mean Nearest Neighbor) and CONTAG (Contagion). Our results provided quantitative data on habitat loss and landscape fragmentation in Ghamishloo wildlife refuge and indicated negative impacts of the ringway on goitered gazelle populations by restricting their movement between habitat patches in this region, which presents a concern for the conservation of this vulnerable species.

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Regarding high economic and conservative values of Zagros forests, and livelihood dependency of local people these recourses, determination of sites with higher conservation index can help us to maintain biodiversity of these forests more efficiently. Therefore, 49 plots with 450 m2 in area accompanied by 1, 10 and 45 m2 subplots were taken as systematic random design in research forests of Yasouj University. The number of species in each plot and subplot was recorded. The conservation values for different physiographic regions of forest were calculated using integrative parameters such as the number of species per plot, number of rare species per plot, number of tree species per plot, Jaccards similarity coefficient and slope of species-log(area). Comparing the conservation index in different physiographic sites revealed that the areas located in the north, hills and lower altitudes can be considered for in situ conservation due to higher number of trees, rare species and total plant species, species-log (area) slope and lower amount of Jaccard similarity coefficient. But, vegetative sites located in lower slopes and south, because of lower conservation index, can be used for other multipurpose forestry activities. Using this index for different forest areas can be potentially conducted for better conservation and management of Zagros forests.

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To implement correct management of forest ecosystems, enough information in relation to the structures of tree species is necessary. In this study, the structures of trees species in Fagus, Fagus-Carpinus, Carpinus-Fagus and Carpinus-Quercus types were investigated and compared in Hyrcanian forest. The data used in this study was collected from 239 plots with an area of 1000 m2 in Gorazbon district of Kheyrud forest, and Crancod (ver. 1.3) software was employed to calculate the uniform angle (Wi), Mingling (DMi), DBH dominance (TDi) and Height dominance (THi) indices. The result of uniform angle index showed a random positioning for the trees in the studied types. Also, the result of mingling index showed a low mixture for four studied types. The result of this index indicated an intra-specific competition for Fagus orientalis and Carpinus betulus and an inter-specific competition for other species. The average value of DBH and Height dominance indices showed a relative similarity among the studied types. The result of these indices showed that some species such as Acer velutinum,، Tilia begonifolia and Alnus subcordata are dominant and species including Ulmus glabra and Diospyros lotus are dominated. The comparing of similar species structure showed a non significant difference for positioning, DBH and height dominance features in different types. Also, this comparison showed a significant difference in mingling feature of Carpinus betulus, Fagus orientalis, Acer velutinum, Tilia begonifolia, and also deadwoods in the studied types. The utilized indices in this study had a high ability in the description of forest types' structures and also the ecological features of trees species.

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The present study was conducted to evaluate the effects of some physical and chemical parameters of water e. g. pH, temperature, electron conductivity (EC), Fe, silicate, orthophosphate, Nitrate on diversity and abundance of periphyton diatoms in a tributary of the Masooleh River (located 37o 22’ to 37o 23’ northern latitude and 49o17’- 49o19’ eastern longitude in Guilan Province, north of Iran) in summer, autumn and winter, 2011. The study area was 15 km in area, and 5 sites were chosen for diatom sampling. The average depth of the river was 0.5 m with temperature ranging from 14 to 31 0C. Elevation from the sea level and all parameters mentioned above were measured for each sampling site. The samples were collected from surface layer of Epilithon, Epidendron, Epipssamon and Epipelon as natural substrates. The results showed the following ranges: EC: 617-1370 S.cm.-1 pH: 7.82- 8.81 and nutrients: PO43-: 0.02- 0.21mg.l-1, NO3: 1.2- 3.5 mg.l-1, SiO2: 0.02- 6.5 mg.l-1and Fe2+ < 0.02- 0.1 mg.l-1 as an indicator of trophic status of the river. The collected samples were processed and slides were prepared for LM examination. In this study, 23 genera of diatoms were identified. The least and most abundant diatoms were observed on muddy (12.52) and stony (30.86) substrates, respectively. Comparison of mean abundance of diatom population on different substrates (muddy: 23.95± 4.08, gravel: 15.52± 0.97, woody: 17.71± 0.62 and stony: 23.95± 4.08) revealed statistically significant differences between stony, gravel, muddy, and woody substrates (P<0.05). The distribution of diatoms on coarser substrates (wood, stone and gravel) was higher than on softer ones (muddy). Based on the obtained results, woody and stony substrates seem to be more suitable for ecological monitoring of streams than muddy and gravel substrates.

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Persian wild ass, Equus hemionus onager, is a rare subspecies of Asiatic wild ass endemic to Iran, which was historically widespread in arid and semi-arid steppes of central and southeastern Iran. Today only two natural populations have remained. This subspecies is listed as Critically Endangered in the Red List of the International :::union::: for the Conservation of Nature and Natural Resources. Knowledge on habitat use and population densities of this taxon is necessary for its successful conservation. We studied population density and habitat selection by Persian wild ass in Qatruiyeh National Park (QNP). Seasonal habitat use by onagers was studied using clearance transects and standing crop pellet group counts. Line transect distance sampling was used to estimate the abundance of onager in the two main vegetation communities of the park. Onager use of vegetation communities was not significantly different in autumn, winter and spring, but in summer onagers used Artemisia sieberi community significantly more than the Zygophillum-Artemisia community. The most sensible relationships, resulting from multiple regressions, were negative effects of Zygophyllum eurypterum and trough distance. Negative relationship to trough distance showed importance of water resources for onager presence. Population density of onager, estimated through distance sampling, was higher in Artemisia sieberi community (3 onagers per km2 95% confidence interval 1.58–5.7) compared with the Zygophillum-Artemisia community (0.45 onagers per 1 km2 95% confidence interval 028–0.73). The mean density of onager in the national park was about 1.0 onager per km2. Complete protection and suitable distribution of adequate water resources are the main contributing factors to the high density of onagers in QNP.

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To assess seed dispersal by domestic herbivores (sheep and goat) in Central Zagros region, 12 different rangeland sites, located 200 km west of Isfahan city, were studied. For each site, a pooled dung sample of 10 freshly pellet groups from domestic herbivores was collected in four different periods (mid June, July, August and September) during grazing season (in total, 48 pooled dung samples). Dung samples were dried in a dark room by exposing to open air, and then from each a 150 gram sample was kept for two months in the refrigerator at 3ْc as cold treatment. Seed content of dung samples was assessed in a greenhouse germination experiment over a period of 8 months. In total, 2039 seedlings from 50 different plant species (16 families and 48 genera) were germinated from dung samples. Seed content of dung samples was mostly composed of palatable herbaceous species with no dispersal mechanism or adaptation except for the production of many small-sized seeds. The highest and the least number of germinated seeds was observed in July and June samples, respectively. Also, the highest and the least number of seed species was recorded in September and June samples, respectively. However, only a significant difference in seed species composition was observed between dung samples of September and June. Given that most of the plant species recorded in the region’s vegetation were regenerate by seed, seed dispersal via domestic herbivore dungs may have significant role in natural regeneration of the vegetation, if other environmental and management conditions are met. The results of the present research can be especially applied to reclamation of the country’s rangeland ecosystems.

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Bromus tomentellus is one of the drought resistant species that has a relatively well developed in Esfahan province, therefore, in the present study some of the important factors that influence the distribution of this species are studied. In this study, 17 climatic variables from 43 synoptic and climatology stations were selected within and adjacent areas of Esfahan province which the stations managed by Weather Organization of Iran. To reduce the number of variables and determining effective factor was used factor analysis using by principal components analysis with varimax rotation, then the average factor scores in the habitat of this species and the areas without it were calculated and the spatial distribution of the factor scores were plotted in Surfer ver8. The results of the factor analysis identified three factors of precipitation, temperature and wind and sunshine hours. These factors are included 69.70%, 11.98% and 10.14%, respectively and 92% of the total variance of the data. Also, the results showed that both precipitation and cooling temperature are the important factors to presence of these species as dominant and following species and wind and sunshine hours has the least effect on it. Generally, the climate vegetative of Bromus tomentellus can be named in Isfahan province, semi-steppe vegetation region in Fereidan, Freydoonshahr, Semirom, Golpayegan, Khonsar, Meimeh up around the Shahreza and alpine steppe of Natanz and Kashan.

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Preservation and increase of biodiversity is one of the main components to achieve sustainability in agricultural systems. In this study, biodiversity evaluation indexes were used to evaluate and compare agrobiodiversity of vegetable crop systems among all provinces of Iran. In this study the biodiversity evaluation indexes included Shannon-Wiener, Simpson and Evenness. In order to compare the alpha and beta biodiversity in different regions of Iran, the country was divided to 5 different weather and geographic regions, then alpha and beta biodiversity were calculated by species – area relationship according to these areas. The results showed nearly 31 vegetable species are cultivated in Iran that the highest planted area after that tomato, potato and onion was related to aubergine with 6.07% of the total vegetable lands of Iran. The whole of vegetable lands area was 495412 ha that the Fars province with 8.83% of the total vegetable lands of the country, was the first and it was the major producer of 9 species of vegetables. The highest vegetable species richness was related to Esfahan and Mazandaran (29 species) and the lowest was for Chaharmahal bakhtiari (5 species). The Shannon index for these species in total vegetable lands (H) was 0.628 besides this index in highest level has been discovered in Yazd (2.70) and the Shannon index for these species of the total arable lands of the country ( ) was 0.210 besides this index in highest level had been discovered in Hormozgan (1.01). The highest (0.459) and lowest (0) of alpha biodiversity was calculated in north and south regions, respectively. In the other hand, the highest (1.41) and lowest (0.375) beta biodiversity was related to south and north regions, respectively.

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Land cover has rapidly changed due to the relatively high population density, high rate of seasonal and permanent migrants, favorable conditions of natural and cultural, frequency of industrial units, coastal border and harbour and great rate of construction in the mazandaran province in recent years. Land cover changes are led to fragmentation, perforation, dissection, shirinkage, attrition and coalescence in the landscape, which each of them has important concept in the landscape ecology science. In this study, after preparing land cover maps, landscape metrics were extracted then Principal component analysis (PCA) were used in order to selection appropriate metrics for Mazandaran landscape changes analysis during 1984 and 2010. Finally five metric including Class Area (CA), Number of Patches (NP), Largest Patch Index (LPI), Perimeter-Area Fractal Dimension (PAFRAC) and Shannon Diversity Index (SHDI) were selected as the appropriate metrics. The results show an increase in the extent of residential, agricultural, pasture, roads covers (7387, 54655, 88986, 4768 ha, respectively) and sharp decline in forests (162,867 ha). Such that, LPI of forest cover decreased in the Neka, Savadkooh, Sari and Tonekabon cities 17.5, 13.8, 8.6 and 4.9 respectively, during the study period and matrix change were observed from forest to pasture and agriculture in Ramsar and Behshahr cites. More changes have been happened due to digestion forest of patches to anthropogenic covers especially integration of agricultural land.

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Large scale land use/cover changes and habitat fragmentation have been associated with the decline of many wildlife populations in ecological sensitive regions. The main goal of this study was to quantify the spatial pattern changes in Caucasian Black Grouse habitat in Arasbaran Biosphere Reserve, Northwest of Iran in a period of 24 years (1987–2011). Caucasian black grouse (Tetrao mlokosiewiczi) in Iran is restricted to the Arasbaran area, and the populations and range of this specialist bird species have been declining over the last decades. This study focuses on the landscape structure changes of black grouse habitat in Arasbaran Biosphere reserve. We used Landsat Thematic Mapper (TM) satellite images from 1987 and 2011, and ETM+ from 2001, for analysis of the spatial patterns of land use/cover patches. The satellite images were geometrically corrected and classified. For quantifying landscape pattern changes, various landscape metrics were derived from spatial analysis software FRAGSTATS, including NP (Number of Patches), LPI (Largest Patch Index) and TE (Total Edge). The results indicated that the proportion of forest was significantly decreased from 39.95% to 31.95%, and proportion of grassland was decreased from 44.45% to 38.44% during the last 24 years, while proportion of dominated by astragalus was increased from 3.30% to 15.65%. Total Edge (TE) was decreased 8000 meters at altitude over 1800 meters. Our result provided quantitative data on habitat loss and landscape fragmentation in Arasbaran Biosphere reserve and indicated negative impacts of the landscape structure changes on Black grouse habitat.

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Major changes in the vegetation and consequently in the ecosystem functioning of mountainous meadows has been reported in response to herbivore grazing. Nevertheless, effects of protection from herbivores on the vegetation of High-elevation meadows in Iran have not been studied so far. To assess effects of experimentally short-term exclosure treatment on production of mountainous meadows, two meadow sites were selected in Sabzkouh Protected Area in Chaharmahal and Bakhtiari Province. In each site, three 16 m2 (2×8 m) fences were established and in each fence three 1 m2 plots were marked at the beginning of the growing season (April). Similarly, three 1 m2 plots were placed outside each fence (resulting in 18 grazed and 18 protected plots). In the second year at peak vegetation growth and shortly before grazing season (July), above-ground biomass was cut in all plots and then dry weights of vegetative and reproductive organs were determined separately. Grazing exclusion significantly increased total biomass, while it decreased the proportion of reproductive biomass in meadow vegetation community. Protection from grazing increased biomass production of dominant and tall plant species (e.g., Carex orbicularis), but had reverse effects on smaller and less frequent species. Nevertheless, grazing exclusion decreased the proportion of reproductive biomass in all meadow species (except for C. orbicularis) and various species groups (except for grass-like species). The results of the present study may thus be used for objective-oriented management and conservation of high-elevation and mountainous meadow ecosystems of the country

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Livestock grazing is a common human-induced activity with direct and indirect effects even on the ecosystems of protected areas. The present study analyzed the effects of different grazing management methods on species diversity and richness in the steppe rangelands of Saveh, Iran. Data were collected from sixty 2×2 m plots within the areas of three, four-years protected range management projects. Margalef’s and Menhinick's indices, Simpson and Shannon-Weiner indices, and Pielou's index were used to evaluate plant species richness, diversity, and evenness, respectively. All data analyses were performed in PAST and SPSS. According to the mean values obtained for Shannon-Weiner index, Nemati rangeland (with rest-rotation grazing system and moderate grazing intensity) and Shirali Baglou rangeland (with continuous grazing throughout the year and high grazing intensity) had high species diversity with no significant differences among them. However, Chagneh rangeland (with continuous grazing for six months and fairly high grazing intensity) had the lowest diversity. Low values of diversity indices indicated low species diversity in steppe rangelands. Moreover, Shirali Baglou rangeland had the highest species richness compared to the other sites. In the other three rangelands, both species richness and diversity decreased with increasing the grazing intensity. Despite poor range conditions in Shirali Baglou rangeland, intensive livestock grazing and the consequent rise in invasive species increased species abundance and hence, resulting in species richness and diversity in the area. Although over-grazing throughout the year can promote plant species richness through increasing annual species, consequent soil degradation and instability of rangeland ecosystem can be expected.

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The present study sought to determine the interactions between coral reefs and physicochemical properties of water (depth, temperature, salinity, turbidity, dissolved oxygen, pH, chlorophyll a, and water current velocity) and seabed type and slope in Kish Island, Iran. The study area was divided into 19 zones (eight zones with and 11 without corals). Physicochemical properties of water for each zone were extracted from previous studies over the past years. In summer 2010, field sampling of each zone was also performed using a conductivity, temperature, and depth (CTD) instrument. Non-metric multidimensional scaling (nMDS) and cluster analysis (CA) were then conducted to assess the dispersion of coral reefs and to determine the similarity of coral and non-coral zones, respectively. Finally, the similarity percentage (SIMPER) test was carried out in PRIMER 5 software to identify parameters differentiating coral and non-coral zones. The results of nNMDS analysis revealed differences in spatial distribution of coral and non-coral zones. According to CA results, the coral zone in the north of the island (CR6) and the non-coral zone in the northeast of the island (NC2) were similar in terms of physicochemical properties of water. However, they were significantly different from other coral and non-coral zones (p < 0.01). SIMPER test showed seabed slope, water current velocity, salinity, depth, temperature, and turbidity to have the greatest contributions in the dissimilarity between coral and non-coral zones (25.06%, 23.38%, 13.88%, 13.82%, 8.69% and 8.61%, respectively).

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Nonpoint source (NPS) pollution is a major surface water contaminant commonly caused by agricultural runoff. The purpose of this study was to assess seasonal variation in water quality parameters in Gorganrood watershed (Golestan Province, Iran). It also tried to clarify the effects of agricultural practices and NPS pollution on them. Water quality parameters including potassium, sodium, pH, water flow rate, total dissolved solids (TDS), electrical conductivity (EC), hardness, sulfate, bicarbonate, chlorine, magnesium, and calcium ions during 1966-2010 were evaluated using multivariate statistical techniques. Multivariate analysis of variance (MANOVA) was implemented to determine the significance of differences between mean seasonal values. Discriminant analysis (DA) was also carried out to identify correlations between seasons and the water quality parameters. Parameters of water quality index were measured through principal component analysis (PCA) and factor analysis (FA). Based on the results of statistical tests, climate (freezing, weathering and rainfall) and human activities such as agriculture had crucial effects on water quality. The most important parameters in differentiation between seasons in descending order were potassium, pH, carbonic acid, calcium, and magnesium. According to load factor analysis, chlorine, calcium, and potassium were the most important parameters in spring and summer, indicating the application of fertilizers (especially potassium chloride fertilizer) and existence of NPS pollution during these seasons. In the next stage, the months during which crops had excessive water requirements were detected using CROPWAT software. Almost all water requirements of the area’s major crops, i.e. cotton, rice, soya, wheat, and oat, happen in the late spring until mid/late summer. According to our findings, agricultural practices had a great impact on water pollution. Results of analysis with CROPWAT software also confirmed this conclusion.

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The spatial distribution of soil organisms is influenced by the plant cover, thus resulting in a horizontal mosaic of areas subjected to gradients of nutrient availability and microclimatic conditions.This study was conducted to investigate the spatial variability of soil macrofauna in relation to vegetation density in the riparian forest landscape of Karkhe. The vegetation density was determined by calculating the NDVI index. Soil macrofauna were sampled using 200 sampling points along parallel transects (perpendicular to the river). The maximum distance between samples was 0.5 km. Soil macrofauna were extracted from 50 cm×50 cm×25 cm soil monolith by the hand-sorting procedure. Abundance, diversity (Shannon H’ index), richness (Menhinick index) and evenness (Sheldon index) were calculated. Soil macrofauna and NDVI data were analyzed using geostatistics (variogram) in order to describe and quantify the spatial continuity. The variograms were spherical, revealing the presence of spatial autocorrelation. The range of influence was 1724 m for abundance, 1326 m for diversity, 1825 m for richness, 1450 for evenness and 1977 m for NDVI. The kriging maps showed that the NDVI Index and soil macrofauna had spatial variability. The spatial pattern of soil macrofauna abundance and biodiversity were similar to the spatial pattern of vegetation density as shown in the correlation.

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Diversity is one of the most important issues in studies of vegetation ecology. This study was carried out in research forest of Tarbiat Modares University for surveying herbaceous and woody species diversity in relation to topographical factors (altitude, slope and aspect). For this purpose, 48 plots 400 m2 (20×20 m) were established in the region using selective sampling method. Then, the names and canopy cover of all herbaceous and woody species were recorded in the plots. In total, 137 herbaceous and 50 woody species were recognized which belonged to 167 genera and 72 families. In the case of herbaceous species, results showed that elevation factor had a significant effect on species richness, Margalef and Simpson indices. The species richness and Margalef’s index were highest in high altitudes (1450-1700 m a. s. l.), and Simpson index was highest in high elevations (1200-1450 m a. s. l.). Slope had a significant effect on diversity and richness. Richness and Margalef index were higher in 60-90% slopes, and Simpson’s index was higher in low slopes (0-30%). In the case of woody species, results showed that elevation factor had a strong effect on all diversity indices. The results of correlations showed that indices of species richness, Margalef and Menhenick indices were reduced with an increase in altitude. Higher altitudes (1450-1700 m a. s. l.) showed higher amount of evenness. Also, the effects of slope and aspect were not significant on any woody species diversity indices.

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Secondary succession after wildfire usually leads to vegetation types that can differ with the original vegetation in terms of forage productivity and community stability. Plant functional types (PFTs) can be used as ecological indices for assessing effects of disturbances on the natural plant communities. Accordingly, this research was aimed to identify, classify and analyze PFTs in three rangeland sites: burnt in 2004, in 2008, and control (2010), in Jowzak, Northern Khorasan, Iran. Floristic list, percentage cover and 24 morphological, phonological and reproductive plant traits were recorded within 1m2quadrates. PFT’s were determined by applying hierarchical cluster analyses and discriminant function analysis on the matrices of 45 species24 traits and 45 species3 sites, using SPSS software. Four different PFTs were identified. Leaf wet weight, life forms and Twig dry matter contents were the most important traits for PFT classification. Two functional types identified as adapted to fire, and two groups as functional types sensitive to fire. According to the results of this research, the most important indices for the effect of fire on secondary succession of Jowzak rangelands can be the reduction of hemicryptophytes perennial geophytes and annuals, increase of plant height , seed size, seed weight, specific leaf area and leaf dry matter content, and decrease of stem weight, leaf and twig dry matter content.

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The most important pollutants that cause water pollution are nitrogen and phosphorus from agricultural runoff called Non-Point Source Pollution (NPS). To solve this problem, management practices known as BMPs or Best Management Practices are applied. One of the common methods for Non-Point Source Pollution prediction is modeling. By modeling, efficiency of many practices can be tested before application. In this study, land use changes were studied from the years 1984 till 2010 that showed an increase in agricultural lands from 516908.52 to 630737.19 ha and expansion of cities from 5237.87 to 15487.59 ha and roads from 9666.07 to 11430.24 ha. Using L-THIA model (from nonpoint source pollution models) for both land use categories, the amount of pollutant and the volume of runoff were calculated that showed high growth. Then, the seventh sub-basin was recognized as a critical zone in terms of pollution among the sub-basins. In the end, land use change was considered as a BMP using Multi-Criteria Evaluation (MCE) based on which a more suitable land use map was produced. After producing the new land use map, L-THIA model was run again and the result of the model was compared to the actual land use to show the effect of this BMP. Runoff volume decreased from 367.5 to 308.6 M3/ha and nitrogen in runoff was reduced from 3.26 to 1.58 mg/L and water BOD from 3.61 to 2.13 mg/L. Other pollutants also showed high reduction. In the end, land use change is confirmed as an effective BMP for Non-Point Source Pollution reduction.