نشریه حفاظت زیست بوم گیاهان
سال سوم شماره 2 (پیاپی 7، پاییز و زمستان 1394)

This study was conducted by the aim of study the species composition and diversity in the north faced slopes of Sabalan (altitude profiles of Lahrood-Shabil) along 7 transects in three elevation classes of 1500 to 2000m, 2000 to 2500m and 2500 to 2700m in the grass-shrubland dominated habitats. Plant specimens were collected in the fieldworks, and then species were identified using the checklists and reliable literature. Overall, 64 identified species were belonged to 48 genera and 22 families. Poaceae family with 9 genera and 16 species, Fabaceae family with 4 genera and 8 species and Asteraceae family with 6 genera and 6 species are the dominant family and genera. According to the Rankaier's system hemicryptophytes with 50%, therophytes with 31%, geophytes with 16% and chamaephytes with 3% are the growing life forms at the study area. In terms of geographical distribution, 42% of the species are belong to Iran-Turonian region, 22% of those to Iran-Turonian and Euro-Siberian, 12% are cosmopolitan, 3% to Euro-Siberian and other 21% is belong to other regions. From the identified species 6 of them are in threatened status based on the International :union: for Conservation of Nature and Natural Resources (IUCN) criteria. Diversity and evenness of species were calculated using numerical indices. Results of numerical diversity indices (Simpson and Shannon-Weiner) showed significant change according to elevation. However, the evenness indices (Simpson and Smith and Wilson) show no significant change by elevation.

To evaluate salinity and drought stresses as experiments in a completely randomized design with three replications, the present research was conducted at the seedling stage. Plants under study were Trifolium pratense, Vicia sativa, Sanguisorba minor and Secale cereale. Salinity and drought levels applied to the seven levels of NaCl (control, 2, 4, 8, 16, 32 and 64 bar) and nine levels of mannitol (control, 2, 4, 6, 8, 10, 12, 14 and 16 bar). The results showed that root length, shoot length, root and shoot weight of seedlings were decreased with the increase of the concentrations of NaCl and Mannitol in comparison with the control treatment. Vicia sativa had the maximum length of roots and shoots among the four examined plants which were respectively 34.06 and 43.5 cm. According to the results of the present study, Vicia sativa had the highest tolerance to salinity and drought stresses while Secale cereale, Sanguisorba minor and Trifolium pratense had the minimum tolerance to salinity and drought stresses.

It is necessary to recognize the relations between ecosystem components for suitable management of landscapes. Structure and function are two inherent components in each ecosystem. Thus, this study aims to investigate effects of ecosystem structure on soil surface indicators and landscape functional attributes in Fath-Abad Rangelands, Ferdows. In order to this we used Landscape Function Analysis (LFA) method to determine soil stability, infiltration and nutrient cycling using of 11 soil surface indicators. Data submission and analysis was performed by electronic LFA form (in Excel format) . ANOVA was used for determination of different existence between data and Duncan multiple ranges test for difference level. Landscape Organization Index for the area was 0.42. The results showed that different patches have significantly different stability, infiltration and nutrient cycling in the area as most of these characters are maximum in forb, shrub and shrub-grass patches. It may be resulted by specific structure such as strong roots, shaping and inter-density in these patches. In contrast, the inter-patch areas have the least amount of the functional characters that can be explained by the lack of litter and vegetation at these areas. For better management and increased performance characteristics pastures increased vegetation, especially the structure of Forb and Grasses is necessary.

In order to study the effect of plant density and plant orientation on receiving and using of radiation in wheat cultivars, an experiment was conducted at the research farm of Gonbad Kavous University in 2012. The experiment was carried out as factorial based on completely randomized design with three replications. The factors were including: orientation with four levels (North-South, East- West, North East- South West and North West- South East), plant density with three levels (250, 300 and 350 plant per square meter) and wheat cultivars (Kouhdasht and line 17). Variance analysis results showed that that ecological indicators study (consisting of leaf area index, dry matter accumulation, canopy extinction coefficient and Radiation use efficiency) were affected by interaction effect on orientation and plant density, but cultivars had no significant effect on ecological indicators. Leaf area index (LAI) and dry matter accumulation increased with the increase of plant density; in such as a way that plant density, the highest LAI (8.33) and dry matter accumulation (2294±357.3 g/m2) were obtained in East-West orientation. The increase of dry matter accumulation due to the interception of photo synthetically active radiation was resulted in the increase of leaf area index in East-West orientation. Canopy extinction coefficient (K) was affected by plant densities of 300 and 350 plants per square meter and in plant densities 250 plant per square meter no significant difference in plant orientations was observed. Average of canopy extinction coefficient in this study 0.63 was measured. Radiation use efficiency (RUE) was affected by interaction effect of plant density and orientation. The maximum of RUE was observed in the high plant density and East-West orientation.

Determination of forage quality is one of the fundamental factors for the proper management of rangelands. In order to study the effect of phonological stages on forage quality, three species of rangeland in Yazd province including Hordeum bulbosum, Trifolium repens, and Prangos ferulacea were selected. Samples were collected in three phonological stages: vegetative growth, flowering and seed production. Plant samples were analyzed in the laboratory to determine crude protein percentage, acid detergent fiber, dry matter digestibility and metabolism energy. Data were analyzed using ANOVA and Duncan test. The results showed that the effect of phonological stages on forage quality were significant (P

In the present study, standard phytochemical method was conducted to identify quality some allelochemical compounds such as saponins, terpenoides, antraquinons, flavonoides, flavons by using 10 % condensed aquous extract in distilled water or ethanol solvent of root, stem and leaf organs of Atriplex lentiformis.Then the bioassay experiments were undertaken to evaluate the allelopathic potential of various concentrations (0, 20, 40, 60, 80 and 100%) of selected organs by using 10 % condensed aquous extract on radicle length, shoot length and germination percentage of Medicago scutellata to form of factorial examination in completely randomized design in the Hydroecology laboratory of Gonbad Kavous University in 2012. The effect of various concentrations of organs on studied parameters, was fitted to regression model. In the phytochemical examinations of the qualitative the allelochemicals of saponins and terpenoids were observed and confirmed while the allelochemicals like antraqouins, flavonoids and flavones were not detected in the studied organs. The bioassay of various concentrations from the selected organs and interaction effect of them showed the significant effect on different parameters of germinations of Medicago scutellata at p- value 0.05. The greatest hampering effect was found in the aquous leaf of Atriplex lentiformis as compared with other organs. The germination percentage of the M. scutellata compeletly was hampered by 80 and 100% of leaf organ. The effect of various concentrations on different parameters of germination indicated the highest R- square which was including linear and exponential dependent. The greatest R- square (R2=0.98) was found in aquous extract of root on the radicle length of the studied plant with linear dependent.

In order to study changes of production and utilization of Salsola laricina at growth season and Grazing season, the site of Khoshkerood-e- Saveh selected which is indicator of steppe rangelands. To evaluate the vegetative and productive characteristics and forage consumption by livestock at different stages of plant phonology, this experiment was carried out during 2010-2012 years. Thus remaining amount of forage grazing was harvested until a month intervals, and consumption rate was determined by subtraction between harvested forage and fenced plot forage. Finally, in order to study the effect of harvest months on the production and consumption under investigation in the study area, data were analyzed. The results showed that production has fluctuated during different rainfall. In Years 2011 will produce more forage than the average (264 kg ha) of about 7 percent higher and in 2010 produced the lowest yield that it was 6% lower than the average. This species share in rangeland production was high and on average four years, about 50 percent of rangeland forage was produced by Salsola laricina. In average three-year, peak rangeland production was in May and has decreased in June. On average, 92 percent of production was grazed by livestock along grazing year. Greater share of rangeland forage consumed in November and drying time of plant. Salsola almost grazed in autumn and winter and other species grazed when they were green. Due to the palatable nature and quantity of such product, is a good source of forage in winter pastures.

Heavy metal pollution in soil is one of the major environmental problems throughout the world. Since metals uptaken by plants and fruits are transferred to humans, this problem is more serious in agricultural and garden soil. The object of the present study was to investigate and assess heavy metals in vineyards soil of Malayer plains. Random sampling system was used in this study. Totally, 25 soil samples were collected from the depth of 0-20 cm. Soil samples were analyzed by HR-CS AAS with flame method. The mean concentrations of Copper, Lead, and Zin in the soil samples were 7.36, 6.91, and 54 mg/kg respectively which were lower than the world average and earth crust for these metals. The results showed that positive and significant correlation between Cu - Zn, Cu - Pb, Zn - Pb and pH – EC. It seems that in addition to geology and parent materials, chemical fertilizers and animal manure are the sources of metals to vineyrads soil. In addition, copper fungicides have not played any role in the increase of the concentration of copper with regard to the application of sulphur as fungicide. At present these heavy metals are serious risk for these vineyard soils.

Determining habitat suitability is one of the most important elements of management and conservation of plant and wildlife species. A suitable habitat will have a significant impact on the survival and reproduction of species. Nowadays, the development of statistics and geographic information system has enables us to determine possible habitats for plant species via using geographical distribution modeling techniques. Using the Ecological Factor Analysis Model (ENFA), the present study has modeled the habitat of Fritillaria imperialis L., as a species with numerous industrial and pharmaceutical applications. To this end, species’ presence data was gathered with systematic sampling method with 500 presence points. Then the data was registered and then, the data was ultimately converted to a map of the vector format. Environment variable maps such as topographic, climate, and soil were generated by using geostatistical and GIS methods. Finally, the habitat map for this valuable species was generated. According to ENFA analysis, the variables of the amount of absorbable potassium, the amount of absorbable phosphorus, Digital Elevation Model, the amount of annual precipitation, and the slope direction of region, are the most significant factors, influencing the habitat selection for Fritillaria imperialis L in the study area. The amounts associated with being margininety, specialization, and tolerance in this study were 1.547, 6.325, and 0.158, respectively indicate that Fritillaria imperialis L is specialization species within its habitat sites. Boyes index was used to verify the correctness of this model, which was calculated to be 0.092. The results of the present study suggest that using alternative habitats can prevent the irreversible negative consequences like reduction or extinction of this valuable species.

To compare the decomposition rate of leaves and stems Prangos ferulaceae species during a year, this research was carried out at training and research station Hossein Abad of Fars. The litter bag technique with size of 20×20 cm and 2 mm pores was used in this research. Each bag was filled with 5 gr dried plant specimens. Totally 54 bags with leaf, stem, composition of leaf and stem treatments with three replications were placement in the field. Bags were taken at intervals of 60 days (6 times in a year). The amount of nutrients N, C, K, P and C/N in leaves, stems and the composition of leaves and stems were measured after each sampling. The results showed that more nitrogen and lower hemi cellulose in the leaves rather than stems was caused tendency of microorganisms (especially bacteria) in this organ. As a result faster decomposition and increase the mineralization rate of its nutrient happens. Generally, the plants decomposition rate depends on the ratio of carbon to nitrogen. As this ratio is lower; the resistance of plant against the decomposer factors will be lower.

Functional diversity is directly related to ecosystem services, biomass contains most of them such as food, conservation, tourism and pollination. This study attempted to test such assumptions as (i) The existence of close relationship between plant production and the community-weighted mean trait values (CWM), as expected from the “production ratio hypothesis” (ii) existence of close relationship between Rao’s functional diversity index with plant production according to “Tilmann hypothesis of diversity” to predict plant production and to find the best relation between plant production with environmental factors in the wooded rangeland of central Zagros. The results showed that among value of CWM, the most R² was related to functional diversity index of weighted mean of leaf index equal to %37. Also the amount of this index for Rao’s functional diversity index was %18 showing that this index only is able to explain about 18 percent of plant production variations. The most community-weighted mean values showed increasing trend with increasing plant production. It was observed that a combination of abiotic factors, Functional diversity (FDQ) and CWM index including of rainfall, temperature, CWM-ME, CWM-Long Leaf, and CWM-Height variables explains about 76% of plant production variations and can be regarded as the most appropriate model to forecast plant production. The results indicate the functional identity of plant community as proposed by Grime is the main driver of ecosystem function compared to niche complementrity hypothesis.