FOREST RESEARCH AND DEVELOPMENT
Year:2020 | Volume:5 | Issue:4 |Papers Count:11

In this study, using four commonly used modeling methods for assessing the potential habitat of yew species (generalized linear and additive models, classification and regression tree and random forest) and maps of the bioclimatic and topographic, the suitability map of the yew species in Hyrcanian forests was prepared. The evaluation of models by using AUC criterion (GLM=0. 863, GAM=0. 871, CTA=0. 781, and RF=0. 922) showed that the random forest model has the best performance in which slope percentage and solar radiation index are the most and least important variables, respectively. The present study showed that the presence probability of yew species in relation to slope percentage in the study area increases from 30% and then levels off. In the current conditions, the area of suitable habitats for yew species is about 10. 5% of the studied area. The results of this research indicated that in the current climatic conditions, the suitable areas for presence of yew species are in east and center of the study area that will help to manage, protect and restore the habitats of this invaluable species.

The aim of this study was to find the best explants and sampling period under different sterilization treatments in order to achieve a suitable and optimal protocol for tissue culture studies in Buxus sp. Explants were prepared from different parts of the plant, including leaves and stems. At first, detergent disinfection treatments and initial washing with ordinary water containing a few drops of liquid dish for four to five minutes were performed to remove surface contamination. The Explants were flushed with distilled water five times. Then, under laminar Floe sterilization, use 13 different treatments and disinfect five times each treatment with distilled autoclaved leachate and at the end of the appropriate samples (leaf samples of 0. 5 to 1 cm Squares and stem samples of 5 to 10 mm) were isolated from plant material and placed on a PDA medium inside autoclaved petri dishes alongside a flame. In order to measure the contamination, cultures in a growth room with a temperature of 26 ± 1 ° C with a light intensity of 1000 to 1500 lux and dark (incubator) were investigated. The results showed that samples of spring season have less microbial contamination than those in the autumn season. On the other hand, leaf samples showed less contamination percentage compared to stem explants.

In this study, the effects of different levels of salt, cow manure and vermicompost on plant growth and increasing the salt tolerance of two years plants, were investigated. In a factorial experiment and completely randomized design (CRD), three levels of organic amendments (1-soil 2-80% v/v soil + 20% v/v vermicompost, 3-80% v/v soil + 20% v/v cow manure) and three levels of salinity (1, 4 and 7 dS. m-1) with three replications per treatments in greenhouse were applied. In this experiment, media without organic amendment was considered as control. Stress duration was three months. Results showed that increasing soil salinity levels progressively decreased the growth characteristics, chlorophyll, and fresh and dry weight of plant and increased activity of catalase and sodium and chloride absorption. Vermicomposte treatment better than control and cow manure increased fresh and dry weight of shoot, relative water content of leaves and potassium. The highest fresh and dry weight of shoots, were obtained in the moderate salinity level (4 ds/m) and vermicompost treatment by 239. 83 and 143. 53 g respectively. Using of cow manure and vermicompost in low level of salt (1 dS. m-1) did not show significant effect on sodium absorption.

The purpose of this study is to introduce a method for improving the accuracy of mapping mangrove covers by integrating CART algorithm and vegetation indices using Landsat 8 imagery. In this study, 7 vegetation indices were calculated including DVI, NDVI, NDII, IPVI, MNDWI, SAVI, and OSAVI. The important indicators and thresholds were identified by the CART algorithm in R-software and then the Mangrove cover besides surrounding areas was mapped using the decision tree technique. The results of accuracy assessment based on comparing control points which recorded by GPS with SPOT 6/7 images showed that the resulted map had a general accuracy of 80. 97% and a kappa of 0. 74. Using moderate resolution satellite imageries for mapping mangrove is difficult due to background reflectance effect (e. g. water and soil) and mixed pixels considering environmental conditions. Results demonstrated that this approach could produce information about mangroves for decision makers in order to conservation and management planning.

The main purpose of this study was to model fruit production in different crowns’ diameter classes of hawthorn trees in a part of Chahar-Tagh forest located Chaharmahal and Bakhtiari province. 30 circular plots, each with 1500 m2, were conducted using systematic random network. The trees were divided into 6 diameter classes of the crown and in each diameter class, fruits of 10 trees were measured. In addition, for each selected tree, total height, diameter at breasts height (dbh), diameter of crown and crown ratio were also measured. The results showed that there is a significant difference between crown diameters in terms of fruit production. The results of modeling estimation of hawthorn fruit using one-way ANOVA showed that linear model with variables of dbh and the combination of average diameter of crown and crown ratio are the best variables in terms of model selection criteria. The result of model validation also confirmed this result. The results of the model showed that the average fruit production was 150. 7 kg/ha. Totally, for 50 hectares of forest reserve, a production of 7535 kg fruit estimated which provide an income of 301400000 Rials for local communities.

This research was carried out for investigating the effect of environmental factors on plant types in Arasbaran forests. To do so, for considering of the different conditions, sampling was carried out based on the landform units, and the size of a squared sample plots, 400 m2 was determined by the minimum surface area method. According to the landform units of the study area, 27 plots were established and after recording the existing data in each plots, the soil samples were collected. Then, using PC-ORD software and Cluster analysis, vegetation of study area were classified and after that, Principle Component Analysis and XLSTAT software were used to analysis relationship between vegetation and environmental factors and determine the most important factors. Regarding to Cluster analysis, six plant types were identified and some species such as Quercus macranthera Fisch. & C. A. Mey., Carpinus betulus L., Pyrus glabra Boiss., Berberis vulgaris L., Prunus cerasifera Ehrh., Palliurus spina-chiristi Mill., and Mespilus germanica L. were dominant species of plant types. Also, the results of the PCA analysis showed that silt, potassium, porosity, bulk density, phosphorus and clay are the most effective factors on distribution of plant types in the study area. Considering that use of plant species in restoration of a region needs data on their habitat demands, so results of this research could be use in restoration of same regions.

This study was conducted to investigate the non-framed sampling methods for estimating the structure and spatial distribution pattern in Persian oak (Quercus macranthera) stands. Field sampling with distance method as a non-framed sampling methods was done in nine plots, each with one hectare, and totally by 81 points using systematic random network. Density, basal area, canopy of trees and spatial distribution pattern were calculated. According to the results, the Hopkins spatial pattern distribution indices were calculated. The results of Clump distribution, Eberhart and Johnson-Zimmer indices showed uniform distribution pattern for the species. In addition, structural indices showed that the value of the indices of distance to neighbor was 4. 45, height difference was 0. 28, diameter difference was 0. 17, and the species interspecific index was 0. 73 which indicate high composition of Q. macranthera with other accompanying species in the studied area. Also, the average value of the uniform angle index was 0. 52. Density, basal area, canopy of trees resulted by sampling method had significant differenc with real amount that resulted from 100% inventory.

One of the most extreme dependencies of local communities in the central Zagros forests is using forest wood for different consumptions. In this study, the demand for forest wood in the Sardasht forests of Lordegan city, in the province of Chahar Mahal – O-Bakhtiari, was studied. The used method in this research is descriptive and quantitative analysis via semi-structured interview. In this regard, 170 interviews and questionnaires were completed by household headman and then analyzed. To estimate the volume of wood consumption, the equation of Huber volume was used. The results showed that, on average, every forest household uses 18. 08 cubic meters of Oak annually for 12 different consumptions, including of: heating water (bath and wash) and air, baking bread, cooking, heating the milk and buttermilk, agricultural instruments, building house, building warehouse and shelter, fencing, tree branches for cattle, making charcoal, and harvesting firewood for sale. According to the results, there is a significant correlation between the age of household headman, cost of household, education level, number of cattle and harvesting crops with consumption of wood forest.

In this research, factors affecting entrepreneurship and creativity of students in agricultural and natural resources were studied. Initially, various entrepreneurship components of the students were studied to identify the strengths and weaknesses and make decision makers able to make appropriate decisions in order to promote student entrepreneurship based on the results. Considering the nature of the subject and the purpose of the research, this research is based on the method of data collection, descriptive survey and purposeful application. The data gathering tool in this research was a standardized questionnaire of Kordenaeej entrepreneurship and Abedi's creativity questionnaire. The population included 2454 students that studied at the Faculty of Agriculture and Natural Resources in the academic year 1394-1395. To determine the reliability of the questionnaires, Cronbach's alpha method was used in this research. Pearson correlation coefficient, Spearman correlation coefficient and Eta test were used to evaluate the effective factors. The results showed that the relationship between age and number of household members with Pearson coefficients was 0. 091 and 0. 023, respectively, and family income and educational level were not significant with creativity with Spearman coefficients of 0. 041 and 0. 089, respectively. Also, the relationship between age and number of household members with Pearson coefficients 0. 040 and-0. 39 respectively, and family income and educational level were not significant with Spearman coefficients of 0. 028 and 0. 018 with entrepreneurship, respectively. However, the field of study and gender were significantly correlated with Eta coefficients of 0. 51 and 0. 448 with creativity, respectively, with coefficients of Eta 0. 68 and 0. 620 with entrepreneurship, respectively.

This study was conducted to determine the optimal systematic sampling dimensions in forest using Variogram analysis in geostatistics in Catchment Area 30, Safarood forest of Ramsar, with a total area of 100 ha. Sampling was done within a systematic grid (200m×150m) with randomly starting point. To determine the correct spatial correlation between specimens at short distances, from the intersection of the sides of the grid, two other samples were taken at a distance of 50m in two main directions from the central sample plot. Each piece of the sample consisted of two common-centered circular area of 300 and 700m2. The analysis of the selected model for fitting the experimental variogram of the total reference sample plots for the variables of growing stock and basal area/ha indicates the existence of a strong spatial structure and a significant relationship between the measured samples in the 700m2 sample plots. The existence of a weak spatial relationship between samples for basal area/ha in 300m2 sample plots indicate a weak spatial structure in these plots.

In this study, a rapid and efficient protocol was developed for in vitro plantlet regeneration of Lasora (Cordia myxa L. ) using different explants. Seperate experiments, one for shoot regeneration optimization, one for proliferation, and one for induction were conducted in this study. Factorial design 3*7 based on compeletly randomized design was used for shoot regeneration but just compeletly randomized design used for proliferation and induction. The highest frequency of shoot regeneration (4. 33) from cotyledon was obtained on MS medium supplemented with 4. 0 mg/l kinetin (KIN) and 0. 01 mg/l 1-Naphthaleneacetic acid (NAA). The explants started regenerating shoots after 15-21 days in culture. To proliferation the regenerated shoot, the explants were transferred to MS medium containing different concentrations of KIN or BAP with 0. 01 mg/l NAA. Shoot multiplication and elongation took place on the same medium. Indole-3-butyric acid (IBA) at 1. 0 mg/l was most effective for root regeneration. Using the current protocol, it tooks 2 months to regenerate plantlets. The in vitro regenerated plantlets were successfully acclimatized and established in greenhouse conditions.