فصلنامه استراتژی راهبردی جنگل
پیاپی 5 (بهار 1396)

Now in the world and particularly in developing countries according to the different needs of human population growth and natural resources such as forest destruction are faced with that leads to disruption of the ecosystem of nature in the long time. The aim of this study is deforestation detection of Hyrcania forest by using of the Landsat ETM for 2000 and 2009 and OLI sensor for 2017. After needed preprocessing for raise spatial resolution of images, the HIS method was applied to data’s and panchromatic band fused with multispectral bands of both sensor. Classification of images was applied by supervised method and support vector machine algorithm on fused images. The results showed that the process of deforestation Hyrcania forest are differ over time and the rate of destruction has been increased to the year of 2017, So that in2000, the forest area of 49,459 hectares, which amounts to 46 240 hectares dropped in 2009 and 2017 in the amount of 39 521 hectares dropped.

Forest reserves are highly regarded to important for maintaining biodiversity and extinction of many animal and plant species due to human intervention. Wild pistachio forest reserve with the scientific name of Pistacia atlantica sub.sp.mutica located in the northern margin foothills of the Zagros mountain and within 13 kilometers southeast of the Dorud city and between the Marbareh river and the defense industry. The region has a forest stand of wild pistachio seedling and pure trees, which represents a even-aged and elderly great mass and covers 100 hectares approximately. As respects the wild pistachio forest reserve is located in the passage of nomadic tribes and is a suitable place for their camp, each year, is affected indiscriminate and unprincipled exploitation for fuel consumption and fire in the trunks of trees which in course of time would have been destroyed of many trees and of natural regeneration by soil crushed in the region, so we should do care operations such as grazing and fencing and silvicultural and rehabilitation operation such as surface scarification, seed sowing and afforested to preserve and restore and create an uneven-aged stands in this area and with this action steps to achieve the desired goals.

Due to the lack of meteorological stations in Iran and the importance of the element temperature daily temperature in all the planning, estimating air temperature is very important in areas without stations. In areas that have environmental implications that are more important. The aim of this study was to evaluate univariate methods (inverse distance weighted regression) and multivariate (logistic regression) to estimate minimum and maximum air temperature is in Chaharmahal and Bakhtiari Province.
Previous studies using a variable pattern (above sea level) in multivariate interpolation methods used in this research, in addition to elevation above sea level, the covariates (independent) was another. In this regard, the potential covariates in the regression model were eligible to enter, then qualified variables in multivariate regression were used.
Comparison of interpolation methods showed that three-variable regression (longitude, latitude and altitude) with the R2 =0/98 as the best method for interpolation of daily minimum and maximum air temperature is in Chaharmahal and Bakhtiari Province. Therefore, it is recommended for a more accurate estimation of the temperature of the variables used daily minimum and maximum.

During last decades¡ climate change¡ increasing temperatures and drought along with their consequences are considered as most key challenge for human society. Rising temperatures trigger events such as floods or droughts that cause unpredictable changes in plant species diversity. Among the affecting biotic and abiotic agents¡ drought and pathogenic fungi are most stressful factors on the forest trees health. Iran is categorized among low forest coverage countries. Related to these forest¡ Zagros forests as oldest oak forest in the world lays down in west of the country. Due to various species of flora and fauna¡ this region is known rich. These forests not only highly protect the soil and supply water¡ but also provide around 45% of water reservoir in Iran and help economic development in the country. The charcoal disease is a major problem in the oak forest. The disease initially was recognized and then reported from Hyrcanian forest and Zagros in 1390. The disease was spread in the whole territory of Zagros Mountains causing deaths of a million hectares of oak. Yet¡ there has not been a concise and comprehensive information about the risks and threats to the country''s forests. In current study¡ we review the similar studies on this destructive event to inform experts and officials. The aim of this study was to collect information on oak charcoal diseases focusing on evidence and apparent signs¡ their expansion¡ and finally understanding the process and interaction with forest trees¡ methods of control and their management.

Forest and rangelands in the Near East are closely inter-related natural resources, often found within the same ecosystem. The management of forest and rangelands in arid and semiarid lands, as silvicultural or silvo-pastoral systems provide goods and services which satisfy the diverse needs of society and lay the foundations of a strong rural economy. The aridity of the Near East Region, its low forest cover, and the poor quality of its rangelands, coupled with high deforestation rates and overgrazing in some countries, make natural forests and range systems vulnerable to further degradation and consequently to exacerbated soil erosion, loss of topsoil, desertification and lower carbon stocks-all of which lead to increased emissions of greenhouse gases(GHG), and more rural poverty and migration to cities. The primary objective is to provide an overview of the actual status and potential of forests and rangelands, their potential contribution to national economies and their impact on dependent populations in the Near East.