Showing 3 results for modaberi
Amir Modaberi, Javad Soosani, Shyda Khosravi,
Volume 2, Issue 1 (9-2015)
Abstract
The main objective of this study was to estimate the effect of decline disturbance on diameter distribution of coppice oak trees in central Zagros region. For this purpose, two similar stands with equal areas (32ha) in central Zagros (Shorab in Lorestan province and Zarabin in Ilam province) were selected. Diameter at the breast height of declined trees was recorded before and after cutting using 100% inventory method. Following probability density functions (PDFs) Beta, Jonson, Weibull, Gamma, Normal and Log-normal were fitted to the data. The results of goodness of fit tests shown that Beta, Weibull and Jonson PDFs were fitted well to diameter of woody stems in Shorab but Jonson, Beta PDFs were much m ore suitable for Zarabin region. The difference of diameter at hight breast was studied in two stages of before and after declining by means of mortality PDF and using different PDFs. There was a big difference in diameter classes between before and after decline disturbance according to mortality distribution. There was no difference between before and after decline disturbance based upon statistical distribution fitting criteria. Outbreak of decline within this region had merely similar influences on all diameter classes, and as a result, it had not a significant effect on overall diameter fit.
Amir Modaberi,
Volume 4, Issue 1 (reserch article 2024)
Abstract
Background and objectives: Primary information about different methods of vegetation sampling is important to researchers to decide about their sampling.
Materials and methods: In this study we applied five distance methods (closest individual, nearest neighbor, second nearest neighbor, joint-point and point- centered quarter method) to estimate plant density and canopy cover based on different inventory net (100×100, 150×150, 200×100 and 200×200)m in Manesht and ghalarang ilam province were compared according to their accuracy.
Results : The result showed that among the distance sampling methods mentioned with different inventory net according to accuracy for density second nearest neighbor in 200×200 inventiry net and for canopy cover respectively point- centered quarter method in 200×100 and 150×150 were more suitable methods for this region. Because this formulas could provide an acceptable estimate based on ±10% accepted accuracy.
Conclusion : According to this study distance sampling methods in Zagros forest was relatively good accuracy and can be used in other research and executive censuses.
Amir Modaberi, Ali Mahdavi, Hamid Amirnezhad,
Volume 4, Issue 1 (reserch article 2024)
Abstract
Background and objectives: In addition to wood production, forests have many environmental and social resources that most of them are often lacking in the market.
Materials and methods: In this paper five cases of ecosystem services forest ecosystem was considered from an economic perspective and they have been evaluated to various approaches. For this purpose, the recreational value of the area by using a conditional valuation method and the value of carbon sequestration, the maintenance of soil nutrients, the value of water regulation and the value of non-food products in the region were estimated by using the replacement cost method. Then the total economic value of these functions was estimated.
Results: According to the results total economic value and the annual value per hectare of forest ecosystem were 576413505.1 Toman and 17243407.560 Toman in year respectively. The functions of Carbon sequestration with equivalent value 574114967.1 thousand Toman had the most value and Recreational function had the lowest total value among other functions with equivalent value 126618 thousand Toman per year.
Conclusion: The results of the study, as well as other similar studies can be concluded that natural resources with regard to the future exploitation process, they are more under pressure and rarer, So it is necessary that with the optimal using of these valuable ecosystems, this natural heritage has been protected. With understanding the economic value of the whole ecosystem, programmers and policymakers are able to make more comprehensive decisions and determine the precedence between available options that makes optimal use of it.
