Showing 4 results for Jalali
Farhad Ghasemi Aghbash, Seyed Gholamali Jalali, Vahid Hosseini, Seyed Mohsen Hosseini,
Volume 2, Issue 3 (4-2014)
Abstract
The decomposition of leaf litter has important in the ecosystem level through regulating buildup of soil organic matter, regulating of nutrient for plant growth and influencing the flux of Co2 from the soil. Several studies have introduced Home-field advantage (HFA) as an index for indicating more rapidly decomposition process of litter in its own site. In the present study, beech and alder sites and Norway spruce plantation of lajim region were selected for testing the hypothesis that decomposition of litter in its own sites is happening more rapidly. Decomposition process was treated for 400 days using litterbag technique. The findings of this study showed that decomposition process to 180 days, the index significantly was negative (-12.96) for beech and alder in their sites but with passing time and simultaneously enhancement of soil biota activity, it was positively increased (27.36). Whereas this index was initially positive for beech and Norway spruce (54.67) and also for alder and Norway spruce (34.58). Then reached at maximum rate after 180 days. The obtained results confirmed that the decomposition process of litter was more rapidly in its own site. Therefore according to the role and importance of Home-field advantage, we can propose Norway spruce in mixed plantations of beech.
Hamid Taleshi, Seyed Gholamali Jalali, Seyed Jalil Alavi, Seyed Mohsen Hosseini, Babak Naimi,
Volume 8, Issue 15 (5-2020)
Abstract
The studies show that the mean temperature of the Hyrcanian region has been increased by 0.74 siliceous degrees in the twenty recent years. In this research, the current and future distribution of Chestnut-leaved oak (Quercus castaneifolia C.A.M.) was studied using an ensemble method including five different species distribution models. We used five general circulation models under two reprehensive concentration pathway (RCPs) to project the impact of climate change on the distribution of Chestnut-leaved oak by 2070. Also, the stable, gained and lost suitable habitat of Chestnut-leaved oak were determined using range size change analyses under climate change. The results showed that the area of suitable habitats with high certainty would be increased by 16.80%, while it would be decreased by 29.80% under RCP 8.5 by 2070. The results of the range size analyses of oriental beech showed 54.12% of suitable habitat would be stable under RCP 4.5 while it would be decreased by 23.85% under RCP 8.5 by 2070. Also, the gained suitable habitats would be 62.68% and 42.36% under RCP 4.5 and RCP 8.5, respectively. It is suggested that the climate change impacts should be considered in the management decisions and conservation plans related to the Chestnut-leaved oak in the Hyrcanian forests. Further, the suitability of habitats under climate change should be accounted for plantation and reforestation by Chestnut-leaved oak.
Mis Jahede Tekeykhah, Dr Mohsen Hossini, Dr Gholamali Jalali, Dr Jalil Alavi, Dr Abbas Esmaili,
Volume 8, Issue 16 (10-2020)
Abstract
Increasing the temperature of the urban environment is one of the most important environmental problems in cities. The purpose of this research is to evaluate the importance of different tree types as a way to adjust temperature and then to propose cultivating temperature modifications in urban conditions. To do this, firstly, in each of the desired tree species (Sycamore, Siblings, Acacia, Sanguinea and Pine) and a flat-bed area with similar physiographic conditions as the control area, measurements of temperature and humidity in the four main directions and center of each brigade In two summer and winter seasons, digital thermometer and rheumatoid arthritis was performed in 5 replications. Independent t-test results for comparison of mean temperature parameters showed that there was a significant difference between the mean temperature parameters in vegetation and control areas. Since the vegetation areas are cooler in comparison with the control areas in the same conditions of the air and the physiographic conditions are cooler 4885.6 °C in the summer and 14.3% warmer than the perimeter environment in the winter. The results of Tukey's test showed that the most species of the species studied in the summer season were 10.5, 11.6 and 12.25 degrees Celsius respectively, and the maximum reduction in temperature (instantaneous temperature, minimum and maximum temperature) The highest amount of temperature rise (temperature, minimum, and maximum temperature) in winter is 7.24, 4.25 and 7.271 °C, respectively, relative to the surrounding area. The total area of the studied masses was 28.8 hectares, which was 6.48 °C for the summer, and the air temperature increased by 14.3 °C in winter. Therefore, with an increase in each hectare of green space, the appropriate species are 2.61 °C in summer and 1.26 ° C in winter. The results showed that the type of vegetation could have a significant impact on urban climates.
Hadi Bayati, Akbar Najafi, Javad Vahidi, Seyed Gholamali Jalali,
Volume 9, Issue 18 (9-2021)
Abstract
Introduction and Objective: Rapid, low-cost and accurate estimation of tree metrics in the forest ecosystem is one of the challenges facing forest managers and inventories. Therefore, given that the forest areas of northern of Iran, mainly deciduous and uneven-aged forests, are covered with various tree species of different sizes, mensuration techniques could be developed and established to suit the particular circumstances. Methods used in forest inventory should be user-friendly, repeatable, relatively low cost, and also have high accuracy and precession for forest inventory operation.
Materials and Methods: Thanks to technological advances in the photography industry, one of the attractive and proposed methods could be the use of digital cameras, in which the potential and performance of this method was evaluated to estimate diameter at different heights of trees. For this purpose, using a digital camera which is mounted on a pre-designed horizontal index and in different shooting distance, diameter at stump height, DBH, and diameter at top of trunk for 108 trees, in REFTMU and in the altitude range of 750 to 1100 meters above sea level and in autumn was estimated. The distance from each shooting station to each tree was captured using the audio and laser rangefinder of the Vertex device as well as the laser meter.
Results: The overall results showed that at 95% significance level, there was a significant difference with real data only in estimating the diameter at stump height. It is also showing an underestimation in estimating the diameter at breast height and at the top of trunk, and in estimating the upper trunk diameter, it was overestimated. The lowest amount of %CV.RMSE was also observed in estimating breast diameter (4.99%).
Conclusion: The evaluated method showed that in the middle classes of metrics captured data, it was more accurate and less error than the upper and lower classes. The results also showed that with increasing the distance of the shooting point, the error rate was increased. Consequently, the results of time study showed that the average operational time for capturing data in digital camera and the traditional method were 3.88 min.tree-1, and 3.42 min.tree-1, respectively.
