ECOPERSIA
Volume:8 Issue: 3, Summer 2020

Natural regeneration will guarantee forest future and sustainability. Ecological factors (soil and physiology) may influence regeneration process and provide a variety of sites favorable for seed generation and establishment of different plant species. The present study aimed to evaluate effect of environmental factors on Fagus orientalis regeneration in Kojoor Forest, one of Hyrcanian inscribed sites on UNESCO's Natural World Heritage List.

After determination of high valued and undisturbed stands of F. orientalis Lipeskey on the vegetation map, sampling was carried out with 2.5% of statistical intensity (the surface area of each plot was 0.1ha and statistical network dimension was 200×200m2). The effects of abiotic ecological factors including topography (aspect, elevation, and slope), soil type (pseudoglay, brown forest soil, and brown marmorized), canopy closure (50-70% and >70%) on abundance of regeneration were studied on 60 plots.

The mean density was 0.52seedlings/m2, and Fagus orientalis Lipeskey, and Carpinus betulus fastigiata comprise 82% of seedlings. F. orientalis prefers north faced slopes (Northeast and northern) (probability of 95%; p= 0.044) and the highest seedlings abundance occurs in the elevation of 1,000 to 1,200m a.s.l., while, the altitude of 700 to 800m a.s.l. had the lowest density of seedlings (probability of 95%; p= 0.034). This species more is found on the slope of 0-40% (probability of 95%; p= 0.012) on the pseudoglay and forest brown soil (probability of 99%; p= 0.001). Canopy covers between 50-70% are more suitable for this species and canopy cover >70% had the minimum number of seedlings per hectare (probability of 95%; p= 0.021).

These set of environmental conditions are optimal conditions under which F. orientalis as a climax species of the Hyrcanian Forests will grow and reproduce and Kojoor Forest is a developed old growth forest with the best environmental conditions for establishment and regeneration of climax species like F. orientalis. This site is an undisturbed forest with less anthropogenic effects and diverse topography and soil types which make it the best site of the Hyrcanian Forests.

Ferula L. is one of the largest genera from Apiaceae family with about 180 species, which grow in semi-arid rangelands. One of the challenges associated with this genus in their natural habitats is drought and additionally, in case of F. haussknechtii H. Wolff ex Rech. F. species is allelopathy caused by companion with Artemisia persica Boiss.

The present study aimed to investigate the roles of Arbuscular mycorrhizal fungi (AM fungi) in the growth, physiological characteristics, nutrient uptake, and survival of Ferula haussknechtii H. Wolff ex Rech. F. grown under the interactive influences of drought and allelopathy stress conditions. Four levels of allelopathy stress, three levels of drought stress, and two mycorrhizal treatments (AM and Non-AM) were applied to the pots in a completely randomized design with a factorial arrangement.

Based on ANOVA results (p≤0.05), the survival capacities of the Non-AM inoculated plants were significantly less than those of the AM inoculated plants for all allelopathic and drought stress levels. The maximum values of survival capacity were seen in AM×FC×A1 treatment as 75% and the lowest survival capacity was observed in Non-AM×30%FC×A4 as 29%. In general, AM fungi inoculation significantly increases the root: shoot ratios and mycorrhizal dependency values (p≤0.05). Based on ANOVA results, the highest and lowest values for root: shoot ratios were observed as 0.71 and 0.27 for Non-AM×30%FC×A4 and AM×FC×A1 treatments, respectively. Drought stress and allelopathic conditions have a destructive effect on total chlorophyll content. The maximum and minimum proline content (0.21 and 0.04µmol gFW-1) was observed in treatment of AM incubated with the highest level of drought and allelopathic and in Non-AM incubated with the lowest level of drought and allelopathic, respectively.

AM fungi inoculation had a significant positive effect on total nitrogen and phosphorus content in plant tissues but there was a significant negative effect on total nitrogen and phosphorus content in drought and allelopathic stress treatments.

High salt accumulation has severe adverse effects on soil characteristics. Humic acid can improve the soil structure, soil microbial communities, and absorption and maintenance of mineral nutrients. The aim of the present study was to determine the effects of humic acid on some physicochemical and biological soil properties in soils under salt stress.

The experiment was conducted as a factorial based on RCBD design with four replications. The first factor included humic acid in five levels (zero, 10, 20, 30, and 40mg kg-1 soil). The second factor was salinity stress in five levels (0, 25, 50, 75, and 100mM NaCl). The sampling was carried out in two stages, before and after harvest.

The results showed that S1H5 treatment had the lowest soil electrical conductivity (EC), soil reaction (pH), bulk density, and population of actinomycetes with average values of 0.26dS m-1, 6.21, 1.12g cm-3, and 516cell g-1 of soil and had the highest fungal and bacterial population with an average of 1525000 and 137500000cell g-1 of soil, respectively.

Salt stress has a significant effect on physicochemical and biological soil properties except for the population of actinomyces that their activity was better, at a high level of salinity stress, it had adverse effects on other properties. Although using humic acid improved soil properties. According to the results, using humic acid can be a good solution to reduce the adverse effects of salt stress.

The present study aims to monitor and assess CO2 emission from the soil of different land uses and land covers including rangelands, farmlands, mines, gravel lands, and bare lands (lands characterized with no vegetation) in monthly and annual temporal scales.

Monthly carbon emission was monitored according to the alkali-trap method in a closed static chamber from mid-March 2015 to mid-February 2016. Data on emissions and land use were analyzed in a factorial experiment in a completely randomized design with four replications. To determine the relationship between temperature and humidity factors with changes in carbon emission in each land use, Pearson correlation coefficient was used.

The highest (about 3.44g C/m2/d) and the lowest (0.13g C/m2/d) emission rate was found in mines (in July 2016) and in gravel lands (in January 2016), respectively. The results also showed a seasonal pattern (high in summer and low in winter) of CO2 emission. It was found that while carbon emission positively correlated with soil moisture, it showed a negative correlation with soil temperature in mines.

The results depicted that land management should include proper land use selection and improper land use changes should be avoided.

Mouflon (Ovis orientalis, Linnaeus, 1758) is a mammal with four subspecies in Iran. Ovis orientalis arkal is one of the subspecies that is distributed in east and northeast of Iran. This subspecies, like other Iranian mammals' species, is vulnerable in International Union for Conservation of Nature (IUCN). If necessary, actions are not considered for the protection of this species, it faces extinction in Iran. The study and identification of mammals' ticks are vital since ticks are one of the most important factors that can transmit many dangerous diseases to animals. They transmit viral, unicellular and rickettsia factors which may cause encephalitis, tularaemia, paralysis, and poisoning in animals and human as well. In the present study, hard ticks of Ovis orientalis arkal in Tandooreh and Hezar Masjed Mountains were surveyed during the period 2014-2015. In the present study, 175 ticks have been separated from eight heads of Ovis orientalis arkals' carcasses. After maintaining ticks in vials consisting glycerine 5% and alcohol 75%, they were transferred to the laboratory and identification was done. Based on the results, hard ticks were recorded. They include Dermacentor, Rhipicephalus, Hyalomma, Haemaphysalis, and Dermacentor marginatus (Sulzer, 1776) which have been reported for the first time in this study.

In recent years, interest in quantifying ecosystem services (ESs) has dramatically grown among the scientific society. By increasing global environmental crises as a result of population growth, it is becoming increasingly essential to quantify the impacts that human activities have on ESs. Soil and water assessment tool (SWAT) is a process-based distributed hydrological model that has been widely recommended to quantify the ESs. The purpose of the present study is to employ the SWAT model for quantifying the flood regulation ecosystem service in one of the highest flood prone watersheds in the west of Iran.

In this study, after calibration and validation of daily and monthly discharge using SUFI-2 algorithm, the flood regulation index (FRI) was calculated for each year of simulation period (1989-2017).

The results show that climate variables such as precipitation could severely affect the quantities of FRI in different years. According to middle of 95PPU, the FRI varies from 0.22 in the wettest year of 1994 to 0.72 in the driest year of 2017 with precipitation values of 1080 and 380mm, respectively. The results also indicate that lower, middle, and upper limits of FRI 95PPU show the correlation coefficient of 28, 66, and 72% with the precipitation values in different years.

The available knowledge on the application of SWAT model in addressing ESs can be similarly used in the regions with corresponding environmental challenges of the low delivery level of regulation ESs.

The current study investigated the concentration of Cu, Pb, Zn, Cd, Ni, and Cr in shell and soft tissue of Saccostrea cucullata, water, and sediments of seven stations in Qeshm Island of Persian Gulf.

The samples were digested by a combination of nitric acid and perchloric acid and the concentration of elements was measured by atomic absorption spectroscopy.

The results indicated that the concentrations of Cu and Zn in all samples, Ni in the sediment and Cd in oyster were the highest bio-water accumulation factor were significantly higher than those of bio-sediment accumulation factor. Also, these factors in the soft tissue were higher than in the shell. Furthermore, the macro-concentrators of soft tissue were Cd, Cu, and Zn, while the macro-concentrator of shell was Cd.

The shell can be an appropriate monitoring tool for evaluating Cu and Zn in water and Cu in sediments. Also, the soft tissue can be practical for monitoring Cu and Zn in sediments.