FOREST RESEARCH AND DEVELOPMENT
Year:2016 | Volume:2 | Issue:2 |Papers Count:7

The aim of this study was to investigate the effect of seed source (provenance) on germination and morphological traits of Amygdalus lycioides saplings in salt stress condition. For this purpose, the seeds of this species collected of three sites (Khoor, Ardestan and Kashan). Salinity treatment were considered at four levels (0, 1.5, 3 and 5 ds/m) of NaCl. The experiment carried as factorial in completely randomized design whit three replicates. The measured variables were germination percentage, germination rate, vigor index, shoot length, radicle length, shoot wet weight, radicle wet weight, shoot dry weight, radicle dry weight and leaf number. Result of analysis of variance and mean comparison showed salinity made significant differences in most of the investigated traits. The best response was at Ardestan provenance in control level, but this provenance indicated more sensitive in salt stress. The least sensitive was observed at Kashan provenance. Therefore, without salt stress condition, Ardestan was the best of all studied provenances, but in salt stress conditions, Kashan provenance is preferred.

Today, tourism plays an important role in the global economy. Among the different types of tourism, community-based ecotourism development is an appropriate strategy for preserving natural resources and cultural values. This development is possible through empowerment of local communities and causes the cultural, the social and the environmental stability. In the present study, group decision making approach was used in order to rank the strategic criteria affecting the development of community-based ecotourism in Arasbaran. According to the judgments of experts, strategic criteria affecting the development of community-based ecotourism determined and they were weighted using pairwise comparison analysis. The results showed that most of the identified strategic criteria were related to the weaknesses of laws and management, the strengths of natural resources, social strengths and threats of natural resources respectively with 9, 8, 7 and 6 criteria. The number and weight of strategic criteria related to the social strengths and opportunities revealed in Arasbaran region there are much good potential in the field of community-based ecotourism development.

In this study, herbal samples, through a network inventory 400´600 m were collected from square sample plots 5´5 m which were located in the study area as systematic-randomize method, in 2013. In this forest, 69 herbal species were identified that include 20 woody species (tree and shrub) and 49 herbaceous species that were belonged to the 31 plant family and 67 geniuses. The most abundant of tree and shrub species were Quercus castaneifolia, Lonicera iberica and Pyrus boissieriana, respectively. Also, the most abundant of herbal species wereSilene italica, Alyssum minus and Asperula arvensis. The greatest herbal families in the study area were Lamiaceae and Rosaceae with 8 species, Poaceae 7 species and Asteraceae with 6 species. The most abundance life forms were hemicryptophytes with 31 species (44.92%) followed by phanerophytes with 20 species (28.98%). About 29% of species belonged to the Irano-Touranian region and about 20% belonged to the Euro-Siberia region (elements remaining from Hyrcanian flora). Therefore, regarding to the proportion of vegetation elements, it can be concluded that the study area is as an island that has been remained of flora of Hyrcanian forests which are emerged as an ecotone zone to the adjacent Irano-Touranian region.

Bacillus thuringiensisas biological agent has applied practically in pest control programs. However, the activity of this bacterium under field conditions and direct exposure of sun rays is decreased. In this study, persistence of Pathogenicity of this bacterium under field conditions and the role of protective agents includes active charcoal and starch for the first time in Iran was evaluated. Therefore, concentrations of bacteria alone and mixture with charcoal and starch in completely randomized block design experiment in three periods of time on 2nd instars larvae of Nyssia graecarius Staudinger were investigated and the protective effects of these materials in exposure of solar radiation until 9 days were evaluated. The bacteria insecticidal effect on larvae of N. graecarius was performed on basis this studies pathogenic effect of Bacillus thuringiensis after spraying on plants is decreasing significantly at less than 7 days and after 9 days its mortality was the same as control treatment. Percentage mortality of bacteria, bacteria mixed with activated charcoal, mixed with starch and control after 0, 7 and 9 day light exposure were (76.6, 70, 63.3, 6.6), (53.3, 63.6, 53.3, 10) and (30, 53.3, 40, 10), respectively. Results showed that persistence was increased when bacteria applied with active charcoal and starch and combination of Bacillus thuringiensis plus charcoal is more effective than mixture of Bacillus thuringiensisplus starch. The study showed that for increasing time and power bacteria control protective agents such as activated charcoal can be used.

In this research, the production rate and cost of felling and processing in the first thinning of Tyrum rood forest located in northern Iran has been studied in 2013. The study area was reforested by species such as Populus spp., Cupressus sempervirens var. horizontalis, Alnus subcordata, Acer velutinum in 1984. Overall, 132 cycles of felling and processing were recorded. Time study technique was used for calculating hourly production. After defining work phase elements, the influencing variable on each element was determined using stepwise multivariate regression. The results showed that the time consumption of felling and processing was as a function of influencing variables such as diameter, volume, and tree’s distance. The average production rate for all species was 2.8 m3 per hour. The average unit production cost obtained 61522 Rials per m3. Overall, unit cost of felling and processing operation mostly depends on the tree size and tree branching size and structure. As a general rule, as tree size increases, the unit cost decreases, therefore Populus spp was more economical than other above mentioned species.

The aim of this study was to investigate LAI in the main forest roads edge and comparing it at different distances in hornbeam-beech type. Study site was chosen in Namkhane district of Kheyrud Forest, in addition, LAI values were estimated along with16 transects having 100 meters length from the both edges of roadside into the forest (at each transect 9 points at the distances of zero (roadside), 5, 10, 15, 20, 30, 45, 60, and 100 meters from the main road) by using hemispherical photography method. The results of ANOVA analysis showed the effect of distance from road were significant on LAI value (P<0.001). Based on Tukey’s test, the LAI value at 100 meter was significantly greater than 15, 10, 5 and zero intervals of forest roads (P<0.05). The best correlation between LAI and distances from roads based on values of R2adj (0.60), and RMSE percentage (9.13) was positive power. Results showed that main forest roads up to 15 meters had an effect on LAI. Therefore, the less traffic and narrow roadbed and constructing the standard forest roads with respect to principle of close-to-nature in Kheyrud caused stress reduction on forest ecosystems. In general, when all ecological issues are considered while forest roads construction, roads will have little influence on forest ecological balance.

The current experiment was done on Cypress, as one of the most important species in urban forestry, to provide a hydrothermal time model under controlled conditions in a laboratory. The model is designed with respect to stress tolerance thresholds for seed germination. Five different temperature (10, 15, 20, 25, 30 Co) and drought (0, -0.5, -1, -1.5 and -2 MPa) treatments were applied on the seeds. The optimum temperature (To) and basic temperature (Tb) were obtained 21.05 Co and 6.041 Co respectively. The hydrotime constant (qH) for this species was 0.35. The results showed that the decreasing in water potential and temperature caused germination percentage decrease. Temperature and water potential factors had independent and interaction effects significantly on time and percent germination. Finally hydrothermal time model is provided for the species.