جستجوی مقالات مرتبط با کلیدواژه « sowing » در نشریات گروه « جنگلداری »

Quercus brantii L. is classified as vulnerable species that mostly spreaded out in the middle and southern Zagros as pure stand. Due to the elimination of natural regeneration in Zagros oak forest by overgrazing, fruit picking by human, forest decline, and habitat distruction, different researches were carried out to address natural regeneration problem. Yet, lack of regeneration in these forests still exist. Therefore, in this research we examined some simple approaches based on soil moisture preservation and implementation to find out a practical protocol to establish oak regeneration.In our country, also due to intense exploitation and destruction, forest areas are not in a proper condition. Zagros forest is one of our forest resources that turned to the disturbed forest by over grazing, increasing demand for agricultural land, and population growth is Zagros forest. Due to the high rate of oak tree dieback in the Zagros forest and its specific role in soil and water protection, the rehabilitation of these forests is necessary. The objective of this study is to determine the best method for restoration of Quercus brantii L. forests by sowing seed. this study was conducted in is Alamdar Strait in Behbahan. To this Oak seeds with five replications were planted during the winter in different treatments including by rocks, under oak tree canopy, open ground with super absorbent, open space, and curved pits in different slope, altitudes, and geographical directions. Seeds were washed by tap water to remove soil and other particles. After that they were stilled by 70 percent ethanol and placed in the distilled water 48 hours prior to plant for absorbing water. At the end of the growing season survival rate and height of the seedling was measured and their correlation with environmental factor determined. The results indicated that 25.24 percent of the seeds were able to survive the harsh environmental conditions to the end of growing season (end of the summer). Super absorbent treatment has the highest germination rate (82%) and the lowest survival rate of the seedling (6%). While rocks treatment had the least and highest germination (38%) and survival rates (31%) respectively. The west facing slope has the highest germination (77%) but at the end of the season only 29 percent of the seedling remains alive. Although, the north facing slope 71.4 percent of seed start growing but only 31 percent of the remain alive at the end of the summer. On the other hand the lowest germination (50%) and survival (14%) rates belonged to the seed planted on the ridge. The results also showed that the slope and altitude did not affect the survival of seedlings in the present study. The highest seedlings height was recorded for seedling that growth under canopy tree, while the lowest recorded for the curved pits. In conclusion direct oak seed sowing in the natural habitat provided reasonable results for rehabilitation of Zagros oak forest. Using the result of the present study in different treatment would help to gain better results in survival and growth of direct oak seed sowing.

Rehabilitation of vegetation in degraded areas is one of the suitable strategies for conservation of valuable forest species. This should be done by technical and scientific methods, considering the land ecological capabilities. In some cases the density of pistachio saplings have been decreased and finally died after sowing, because they face sunny and warm months of the year while germinating. Hence this study was conducted in order to determine the best method for taking care of saplings after plantation. The research work was done based on Completely Randomized Design (CRD) with four treatments (sunny, 50% shadow, 75% shadow, 100% shadow) and eight replicates. A board coverage (1×1 m) was used for creating shadows. Sampling was conducted during 5 years, then data were analyzed by SPSS package. The results showed that in the first year, there was not any significant difference among treatments (p < 0.01) in surviving, but differences gradually increased and at the end of fifth year there was highly significant differences among treatments, where Duncan test showed 100% and 75% shadow treatments had the most surviving percentages compared to the other treatments.

Due to benefits of Quercus brantii Lindl. and its important role in soil and water protection, this species is very important in its environment, especially the Zagros area. Because of over harvesting, the existence of this species is in danger, so its plantation must be considered and its sowing methods must be known. Therefore, this study was carried out in Rykhlan nursery in completely randomized design with unbalanced factorial experiment. Planting depth (4-5 cm and 7-8 cm) and time (December and March) was considered as two treatments with 3 replicates and 40 pots in each replication. Results showed that planting time had significant effect on survival and shoot and root dry weight ratio. Planting depth had significant effect on all factors. Therefore, planting in December with 7-8 cm depth had the best results for all studied factors.