نشریه تحقیقات منابع طبیعی تجدید شونده
سال سیزدهم شماره 1 (پیاپی 37، بهار و تابستان 1401)

The implementation of the forest protection plan was started in 2003 in the form of a national plan due to the unfavorable situation of the Zagros forests and with the aim of protecting and developing forests in this region of the country. Considering the national nature of the multi-purpose forestry plan and the allocation of the national budget to it, the present study was conducted with the aim of quantitative and qualitative evaluation of the implementation of the plan in Khuzestan province. In this study, some parts of the forests under the management of the plan in Izeh, Andimeshk, Baghmalek and Indika were selected. At first, the multi-purpose forestry plan was defined based on the law on the protection and utilization of forests in the form of three goals of protection, restoration, and development and, of course, increasing the income of foresters, and all executive projects were included in these goals. To analyze the quantitative data, a one-way analysis of variance and Duncan's multiple-range mean comparison test were used to compare the means of the variables. Qualitative data and data differences between different studied areas were also analyzed using the non-parametric Kruskal-Wallis test. Based on the results of this study, it was found that in Khuzestan province in terms of quantity and quality of the plan implementation, Izeh area had the best performance, and Indika, Baghmalek and Andimeshk areas were in the next rank. The results also showed that the goals in the form of protection of Zagros forests are at the highest quantitative and qualitative levels. Forest development and rehabilitation are the second priority and the least planning to increase the income of forest dwellers and reduce their dependence on forests. Therefore, it cannot be expected that the executive projects within multi-use forestry plan of Zagros forests will succeed without changing the income level of foresters and the natives of the region will have maximum cooperation in advancing the goals of the plan with the government.

In the last few decades, the construction of fish farms on the banks of rivers has increased significantly. The purpose of this study was to investigate the quality of the inlet and outlet water of the rainbow trout farm and also to investigate the effects of the effluent on the water quality parameters of the Masouleh River located in Guilan Province. To perform this study, three stations including the control station at the entrance of the farm, the second station at the outlet of the farm effluent and the third station at a distance of less than 100 m after the outlet of the farm were sampled once every fifteen days for three months (November, December, and January 2019). The results of the study showed that the farm output water had a significant effect on water quality indices such as temperature, acidity (pH), dissolved oxygen (DO), nitrite (NO2-), nitrate (NO3-) and ammonia. The level of dissolved oxygen in the outlet water in the first two months of the sampling (5.75 ± 0.18 mg/L) had a significant decrease (P<0.05) compared to the inlet water and the acidity, nitrate, nitrite and water hardness values ​​in the outlet water (8.23 ± 0.09, 4.83 ± 0.15, 0.09 ± 0.07, 7.55 ± 0.18, respectively) showed a significant increase compared to the input water (P<0.05). Also, the comparison between the stations showed that the third station was more polluted than the other stations and the degree of water pollution decreased as the distance from the outlet increased. According to the results of this study, it can be concluded that the output of the fish farming farm has the highest level of pollution compared to other stations due to the use of low-quality commercial feed, high density, and high rearing activity in the farm and as the distance from the farm increases, the level of water pollution decreases due to the process of self-purification of the river.

The most appropriate method of maintaining soil moisture in planting in dry areas is to cover the surface of the soil around the planted seedlings with natural and artificial mulches. To investigate the effect of different types of mulch in soil retain moisture, two types of natural and artificial mulch were used around the seedlings. This design is in the form of a complete random block with two main treatments including natural cover (gravel and sand) and artificial cover (light and black plastic) and four secondary treatments including pebbles, sand, light plastic, and black plastic and in three areas of Semnan, Ghoshe, and Damghan was performed. A control group was also considered. Each sub-treatment was planted in three replicates and 25 samples (black saxaul) were planted in each replicate. Immediately after planting the seedlings and irrigation, the mulch cover was placed around the seedlings. The soil moisture was measured by TDR device at a 10-day interval. The results related to the soil moisture showed that the level of the soil moisture in the black plastic treatment was significantly higher than other mulches. The results of the height of seedlings showed that the black plastic and control groups had the greatest effect on the soil retain moisture. Despite the difference in the soil moisture percentage in all types of natural and synthetic mulches, this difference did not show any significant change in the studied areas. The results of variance analysis of the seedling height showed that the differences in natural and artificial mulches and the control group were significant at the 99% level, but this was not significant in different areas. Examining the correlation between the seedling height and soil moisture percentage in different treatments showed that the highest correlation was in the sand treatment (R2 = 78.8).

The study of changes in rangeland vegetation at regular intervals and awareness of rangeland conditions is one of the important issues for planning and proper management of rangeland utilization. The present study was designed to study changes in the vegetation features in the grazed and exclosured rangelands in the Razband of Qom province. The vegetation measurement was performed in the form of a pair of transects with a distance of 10 meters from each other. Each pair of transects contained 20 plots. The plots with dimensions of 1 × 1 m were spaced 3 m apart and 10 were placed on each transect. Finally, 240 plots (120 plots inside and 120 plots outside of the enclosure) were evaluated. The data analysis was done by SPSS software and the diversity and species richness were performed using PAST software. Out of a total of 8 plant families, six families were significantly different inside and outside of the exclosure. The exclosure in the study area was significantly increased canopy covered by shrubs and forbs, while the grasses showed no significant difference. Chamephytes, hemicryptophytes, terophytes and class I and III species showed a positive and significant response to exclosure. The T-test for species richness and diversity indices showed that Simpson and Shannon - Wiener diversity indices and Margalef richness index had significant differences. The Menhinick's richness index and evenness index were not significantly different inside and outside of the exclosure. Besides, the RDA analysis to evaluate the impact of exclosure on all of the plant species in plots showed that exclosure had a significant effect on the vegetation (P=0.001, F=29.66). The results of this research showed that a short-term exclosure can cause reconstruction and vitality renewal of plant species such as Bufonia macrocarpa and Artemisia sieberi in the arid rangelands of Qom.

Since there are different statistics on the area, distribution, and density of Zagros forests, continuous monitoring and evaluation of these forests are facing implementation problems. The available statistics and information from Zagros forests are not effective in the management decisions of these forests due to many reasons such as their preparation in the traditional way or their oldness. In this research, a high-accuracy map of canopy density and distribution of Zagros forests as well as the determination of other land uses have been prepared using Sentinel-2 images of 2019 in the south of West Azarbaijan province. The image classifications were performed with the supervised method and ML and SVM algorithms in the ENVI 5.3 software environment. The Bing and Google Earth images were used to prepare the ground truth map to evaluate the accuracy of the output maps. In this research, the five non-forest land uses including ranges, gardens, agriculture, water sources, and barren and residential lands were classified. The results showed that the maximum likelihood algorithm with an overall accuracy of 87.3% and a kappa coefficient of 0.74 was the most accurate in preparing the canopy density map. The available statistics showed that the state of forest cover in the province is not in a favorable condition and the area of Zagros forest in the province is equal to 60200.55 ha, which is equivalent to about 90% of the updated statistics of the forests, rangelands, and watershed management organization of the country (67235,91 ha) in 2020. It can be stated that Sentinel-2 data has an acceptable efficiency in terms of accuracy and cost for preparing the canopy density and distribution map of forest areas and preparing the land use map.

Providing sustainable sources of energy, global warming, and maintaining soil health are the main challenges of the 21st century. Biochar has great potential in addressing these global issues and can be effective in achieving sustainable development goals. Biochar obtained from waste biomass (plant residues, urban and rural wastes) is a catalyst for the anaerobic digestion process and increases bioenergy production due to its mineral content and buffering capacity. This article is the result of reviewing valid online papers from Google Scholar, Science Direct, Research Gate, Elsevier, and Springer. The Results showed high advantages of biochar for using in the production of renewable energy and reducing greenhouse gases. Biochar potentially increases methane and hydrogen productions in anaerobic digestion and is efficient in on-site biogas enrichment, leading to biomethane production with a purity of more than 90%. On the other hand, it can be a cheap and potential replacement for the electrode of microbial fuel cells and reduce the cost of ion-based batteries. The application of biochar in the agricultural ecosystem increases carbon sequestration in soil and reduces methane and nitrogen oxide emission. The structural characteristics such as high surface area, optimal pore distribution, surface reactivity, hydrophobicity, and many functional groups make this adsorbent a suitable choice for the remediation of heavy metals from aqueous solutions. The potential of sustainable use of biochar in biological energy production (biogas and biohydrogen), reduction of greenhouse gases, carbon sequestration and soil health, and wastewater treatment along with its future challenges and perspectives is necessary with the Nexus approach of energy, water, and agriculture.

Approximately, 30 percent of rural residents of Ilam County and Holeilan division are engaged in smuggling firewood and preparing charcoal alongside agricultural and livestock activities. Such activities of smuggling firewood and preparing charcoal are the main causes of the cutting of trees and deforestation in these areas. The purpose of this study is to investigate the factors affecting firewood smuggling and charcoal production in the local communities of Ilam County and Holeilan district and to survey the status of charcoal in the livelihood and income of the villagers in the study area. In this study, the data were collected through a library study and a questionnaire. In the interview section, the attitudes and factors affecting charcoal production were investigated by directly communicating with the studied households. According to the results of factor analysis and examination of items (variables) related to each factor and their factor loadings, three economic-social, legal, and cultural-social factors were identified. The results of factor analysis showed that the first factor (socio-economic) with a specific value of 7.45 had the highest share (62.15%) and the third factor (socio-cultural) with a specific value of 1.15 had the lowest share (9.63%) in total variance explanation. The results of the investigations regarding the status of coal mining in the livelihood system of the studied households showed that each charcoal mining household in the area of Ilam city had 10,800,000 Rials and in Helilan district 11,400,000 Rials on average from the sale of coal in 2019.

The recovery of the soil of skidtrails and the establishment of natural regeneration in them play a significant role in the sustainability of the forest. To conduct this research in the west of Giulan province (Shanderman area), three skid trails with 10 years of age and slope classes: 0-10, 10-20 and 20-30% were selected. A total of 30 microplots (2x2 m2) were determined on skidtrails and adjacent areas (control area), and in them, the type of species and the frequency of regeneration were recorded 100%. In the soil sample taken from a depth of 0-20 cm, Bulk Density and Particle Density and %Porosity were measured. The results showed that there is a significant difference between skidtrails and the control area in terms of bulk density, percentage of soil porosity and species regeneration (p<0.05). The frequency of regeneration of the Acer velutinum species in the skidtrails was significantly higher than in the control area, and the frequency of the regeneration of the Carpinus betulus and Acer capadosicum species in the control area was significantly higher than that of the skidtrails. However, no significant difference was observed between these two places in terms of the regeneration of Fagus orientalis and Alnus subcordata species. There was no significant difference between the three slope classes investigated in terms of regeneration and bulk density, the percentage of soil porosity of skidtrails with two slope classes of 0-10 and 20-30% did not have significant differences (p>0.05). The result is that the time period of 10 years is not enough to recover the physical properties of the soil and establish the regeneration of the skidtrails in this area, and the slope of less than 30% does not have a significant effect on the recovery of the soil and the regeneration of the skidtrails.

This research was conducted with the aim of finding the magnetic field effect on changes in peroxidase enzyme activity, germination percentage, stem length and root growth of black locust seeds. The seed cultivation was done in 3 treatments (control, 4 millitesla and 8 millitesla) with 3 replications. 100 seeds were planted in each of the treatment containers, the sprouts were placed in the magnetic field for fifteen minutes in ten days and then the sprouts were counted. The rate of growth of root and stem was measured by a ruler and after that extraction was done. The obtained extract was placed in a centrifuge device and the peroxidase enzyme activity was calculated by a spectrophotometer in the light spectrum of 420 nm. LSD test was used to analyze the data. The results showed that there was a significant difference between the samples affected by the magnetic field regarding all four factors (percentage of germination, root and stem lengths (cm) and the enzyme activity level) with the control sample (p<0 /05). This confirmed that the buds created under the influence of the magnetic field had a higher physiological capacity. However, no significant difference was observed between the magnetic field of 4 and 8 millitesla (p>0.05). It is recommended for the germination of black locust species, which is one of the resistant and very important species in terms of physiological ability to create a green space, a magnetic field of 4 millitesla should be used.

Roads and highways, as one of the biggest threats to wildlife survival, severely affect the ecological connectivity status of the landscape leading to the fragmentation of existing habitats. This research examines the effect of the Tehran-Mashhad bypass road through the Golestan National Park on the movement of Ovis vignei arkal to identify the best point for locating a connectivity corridor. In this study, multiple scales and theories have been selected to analyze species connectivity. The circuit theory was used for the landscape scale by modeling the bottleneck index, and graph theory was used for the patch scale by calculating the betweenness centrality index (BC). The optimal place for locating the corridor was identified by overlaying the range of the bottleneck index and the shortest path to the patch with the highest BC value. By integrating the circuit and graph theories, the results demonstrated the higher movement patterns in the region's west side due to the higher habitat suitability. Installing a corridor in this spot will be increased the species' movement, maintain its population, prevent species isolation, and consequently improve the state of the downstream habitats.

The valuable Arasbaran forest is a complex and dynamic ecosystem that has always been subject to extensive fires. The purpose of the present research is to utilize the technology of remote sensing and geographic information system and the technical abilities of the Google Earth Engine system in order to prepare a fire occurrence map in the rangelands and forests of Arasbaran. In order to choose the appropriate method and type of satellite between Sentinel2 and Landsat8, the separability index was used. Accordingly, the RdNBR differential index was selected among the different indicators of fire detection to prepare the final map of the last 9 years and the cumulative fire map. Based on the accuracy assessment of the resulting map quantitatively, 84% of the actual fire points recorded by the General Directorate of Natural Resources and Watershed of East Azarbayjan province were placed at a distance of 200 meters from fire polygons extracted from satellite images, which showed the high accuracy of the fire map. The field visit also showed a good match among the fire areas resulting from the processing of satellite images with the existing situation of the region. The current research showed the high potential of these two satellites as well as the extraordinary ability and facilities of the Google Earth Engine system in providing a huge amount of remotely sensed data and advanced processing on them to prepare fire occurrence maps. The advantages of Landsat8 compared to Sentinel2 are having thermal bands and more time series. The spatial and radiometric resolution of both are almost similar, and the low-temporal resolution of Landsat8 will be compensated by combining it with Landsat 9 images. Therefore, in line with the results of similar studies, Landsat8 is generally preferable to Sentinel2. For the correct and scaled spatial data from Arasbaran region, it is suggested to create an integrated and large-scale Geo-database due to the lack of accuracy.

In today's era, human interventions have caused chaos in landscape patterns and degradation in landscape quality. Therefore, identifying landscape aesthetic beauty, and also fundamental planning and valuable areas, and proper planning and design in order to protect and promote the aesthetic value seem to be necessary and unavoidable. In this research, the aim is to investigate the performance of various experimental methods (multi-criteria evaluation using weighted linear combination), mathematical (logistic regression), and intelligent (neural network)) in estimating the suitability of the aesthetic value of Gorgan city. After theoretical studies and determination of effective criteria, mapping and standardization of the criteria were done and finally, the map of aesthetic-value suitability was prepared based on the methods of weighted linear combination, neural network, and logistic regression. In order to evaluate the performance of different methods and choose the optimal method, ground control points and ROC validation methods were used. The results showed that in the map resulting from the weighted linear combination method, a large part of the data was lost as a result of the linear combination of layers and weighting, and the neural network method with intelligent performance and the ability to combine and analyze non-linearly compared to the weighted linear combination method and also performing back and forth analysis compared to the logistic regression method, better separates the value of the studied area. According to the results of this research, it can be concluded that when there is little knowledge about the studied area and it is not possible to conduct field surveys to record valuable points of view, performing the weighted linear combination method can be a solution, but if it is possible to conduct field surveys to prepare a map of real educational samples as a dependent variable, more accurate results can be obtained with the help of the neural network method and logistic regression, more accurate results can be achieved, and in the meantime, the intelligent neural network method has a higher ability to distinguish the values of the environment image.