Iranian Journal of Forests and Rangelands Protection Research
Year:2017 | Volume:14 | Issue:2|Papers Count:6

Fungi are one of the major components in forest ecosystems and play an important role in converting processes as well as soil nutrients recycling and forest site fertility. The aim of this research was to identify beech macroscopic fungi and their associations with physiographic factors include altitude, slope and slop direction. Following winter and spring field surveys in parcels 112, 212 of Kheyroud forest, fungi samples associated with affected beech trees were collected. Totally 75 samples of macro fungi were collected of which 36 samples belong to wood- rotting y fungi. SAS statistical software was used to investigate any correlation between fungi abundance on beech trees and the physiographic parameters and The Duncan test was conducted to evaluate the differences. Results showed significant correlation between the physiographical factors and abundance of fungi (p<0.01). The highest macro fungi abundance was found in altitude of 870-970 m, 0 to 20 percent slope and in the Northern direction.

The increasing degradation of Zagros forests has affected the potential of acorn production of different oak species. There is concern that continuing of this process will destroy the valuable individuals of oaks. Unfortunately, there is no adequate information about acorn productions of Zagros native oaks because of the measurement difficulties. In this research, Koenig method as one of the most common and accurate visual survey techniques, was evaluated on Brant's oak (Quercus brantii Lindl.) trees in forests of Dasht-e Arjan, Fars province, and Darbadam, Kermanshah province during 2009 to 2011. The aim of the research was to test the Koenig method for native oaks of Iran and to present the best regression model for estimation of acorn number of Brant's oaks in the studied areas. Forty sample trees were selected in each study area using stratified random sampling method. For each tree, all of acorns were counted with two methods of crown counting and Koenig visual estimation method. The same procedure was used for acorn counting in the other studied years. Based on the results, the values of R2 and RMSE for estimated simple linear regression were 0.68 and 0.292 for Dasht-e Arjan, while the values of R2 and RMSE were 0.82 and 0.230 in Darbadam. Totally, efficiency of Koenig method was confirmed. This method is applicable for an easy estimation of acorn number of other Brant's oak trees in the studied forests in the following years thus, enhancing the ability for easily identifying seed and valuable oak trees.

Polymorphism occurs in Adalia bipunctata (Linnaeus) and A. dcempunctata (Linnaeus). These ladybirds play important role in biological control programs of insect pests particularly aphids affecting ornamental and forest plants. In order to study polymorphism as well as dispersion in terms of host plants, intensive sampling procedures was conducted in two different climates of Shahrood and Bastam regions during 2015. White-tray and net traps were used to collect the beetles. After transferring to the laboratory, specimens were placed in glass gars with 75% ethanol. Identification was conducted based on general morphological characters as well as of their genitalia. Different morphs were identified based on morphological characteristics including color, size, pattern and number of spots on dorsal surface of the elytra and pronotum. In sum, 26 different morphs of the genus Adalia were identified. Adalia bipunctata (Linnaeus) and A. dcempunctata (Linnaeus).are second and forth compare to other species in terms of their abundances on ornamental and forest host plants( with a frequency of 27%. and 15%, respectively).

Iranian oak forms the dominant forest cover of Ilam province located in the South- Western region of Iran where by effect of climatic conditions changes and incidence of numerous drought, the oak wood borer in a rush manner mode and have been caused the damage to these trees. This research was carried out in order to identification of Oak wood borer, natural enemies and normal efficacy rate of oak wood borer Parasitoids during connective three years (2011-2014). With survey of desert investigations by splitting the dry and semi-dry oak woods were done and different growth phases of oak wood borer separately in two health and parasitoid groups monthly have been investigated. For investigating the adult oak wood borer and parasitoids, samples from contaminated trunks and branches to wood borer in the breeding chambers in the dimension of 10-15 m2 were kept. The result show wood borer pest spices including Cerambyx cerdo (Col., Cerambycidae), Macrotoma scutellaris (Col., Cerambycidae), Chalcophorella bagdadensis (Col., Buprestidae), Agrilus hastulifer (Col., Buprestidae), Chrysobothris parvipuncta (Col., Buprestidae), Lampetis mimosa (Col., Buprestidae). The fungus of Beauveria bassiana and foure species of parasitoids wasps including Trigonura ninae (Hym.: Chalcididae), Atanycolus sp. (Hym.: Braconidae) Oodera Formosa (Hym.: Pteromalidae), Pristaulacus compressus (Hym.: Aulacidae) were identificated. The efficacy of wasps in the host larva phase 2.1 percent and fungus efficacy in the larva and adult insects was 1.5 and 1.1 percent.

An important cause of forest destruction is fire. Fire disturbances affected structure and regeneration of forest stand. This study aimed to investigate the effect of fire on structure and regeneration of woody species in Bazazkhaneh strait forests, the north- east of Kermanshah province. For this purpose, a random-systematic sampling lay out (with interval distance of 100 m) was applied to collect data in 80 sampling plots (40 plots in burnt area and 40 plots in unburnt area) where represented 80-ha of study plot. Results indicated that fire did not change forest composition. Oak, Quercus brantii was the dominant species in both burnt and unburnt areas. In tree layer, tree density, regeneration, and coppice density in unburnt area was significantly higher than those values in burnt area. In contrast, in shrub layer, density of individuals, regeneration, and coppice density in burnt area was significantly higher than those values of unburnt area. A reverse J-shaped diameter distribution was found in both burnt and unburnt areas.. However, fire affected the diameter at breast height (DBH) classes and basal area which was lower in burnt area than unburnt area. Data showed that young trees with small DBH were abundant in burnt area when compared with unburnt area. It was found that presence of young trees was good sign of forest recovery after nine years of fire.

Nematodes are one of the most abundant and effective soil organisms in natural ecosystems such as forests, and have been used as bioindicators in studying the effect of disturbing factors on environment. In this study, effects of fire on soil-inhabiting nematode populations in superficial soil layers (depth of 10, 20, 30 and 40 cm) of Abr forest, city of Shahroud was studied. To compare nematode populations in the soils of burned and unburned areas, a total number of 100 soil samples were taken from the above mentioned depths in two times (one and 13 months after the fire) based on a randomized complete block design. After exteraction by centrifugation or flotation method in a solution of sugar and identification and counting of nematodes, their groupings were performed using a stereo microscope based on morphological characteristics of stoma and pharynx. The results showed that the populations of nematodes were decreased in burned soil at depths of 10, 20 and 30 cm, compared to unburned soil, one month after burning. The highest population decrease was observed at the depths of 20, 10, 30 and 40, respectively in burned soil and in the first sampling date, while the highest population increase was observed at depths of 30, 40, 20 and 10 cm, respectively for burned soil and the second sampling time (P£0.05).