Changes in diversity, biomass and abundance of soil macrofauna, Parrotio-Carpinetum forest at organic and semi-organic horizons

Present study evaluates diversity, abundance and biomass of soil macrofauna in organic and semi-organic horizons in Parrotia persica-Carpinus betulus forest in Shast kola area. Totally 70 sample points were randomly selected from organic and semi-organic horizons then sampling was done by a rectangle 100 cm2 area. Soil macrofauna were separated from soil samples by hand sorting and using Berlese funnel then dried at 60°C for 72h and weighted in 0.001 gr. With using taxonomic classification key, thirteen macrofauna orders were identified. Most of abundance of soil macrofauna in both soil horizons were allocated to Millipedes order. Changes in diversity, abundance and biomass of macrofauna in both soil horizons were calculated. The results showed Shannon diversity index, Simpson evenness and Margalef richness indices in semi-organic horizon were more than organic horizon. Abundance and biomass of macrofauna in semi-organic horizon were more than organic horizon

Nitrogen, phosphorus and carbon dynamics of hornbeam leaf litter (Case study: District one, Shastkalate forest, Gorgan)

The aim of this study was investigation of Carbon, Nitrogen and Phosphorus dynamics in Carpinus betulus L. leaf litter in organic layer of a broad-leaved mixed forest in Gorgan. Fresh litters were collected from five plots in district one, Shastkalate forest and were placed into some litterbags with 2 mm mesh. Then, they were located in the study site. Over one year        (8 sampling), chemical analysis was carried out. Result showed total Nitrogen concentration in fresh litters was 1.5% and after one year increased to 1.9%. Phosphorus concentration in fresh litter was 0.134% and increased to 0.136% after one year. Carbon to Nitrogen ratio in fresh litter was 24.5, but after one year decreased to 17.4. Carbon to Phosphorus ratio in fresh litter was 282 and after one year decreased to 245. Weight of fresh litter was 14.65gr, but decreased to 8.23gr after one year. Nitrogen content, C/N and N/P ratios of Hornbeam leaf litters were correlated with secondary weight of litter. C/N and C/P ratios were appropriated for discriminating of decomposition phases. Hornbeam Leaf litters caused soil fertility and increased site indexes. It is necessary to use Carpinus in reforestation and rehabilitation of destroyed forest, considering climate, elevation and forest degradation density

Seasonal changes of soil organic carbon pool in the managed and unmanaged beech-hornbeam stands

Soil organic carbon (SOC) is a major component of global carbon cycle, hence forest soil as one of the major carbon sinks has a key role in the control of atmospheric Co2 concentrations. Consequently, changes of carbon release or uptake by forest ecosystems due to disturbance or management in an unsuitable period can have a considerable impact on atmospheric Co2 concentrations and global warming. In this study, the effect of selection systems were investigated on seasonal changes of soil organic carbon pool (SOCP) in the mixed beech-hornbeam stand in district one of Shastkolate forest, Golestan province. For this purpose, SOCP was determined in depth of 0-20 cm  from February of 2014 to February of 2015 in four stands with one hectare area (one in compartment 32 of virgin forest) and three in compartments 30, 33 and 31 in managed forest, in which the last interventions date back to 10, 7 and 1 years ago). Soil temperature and moisture changes were measured through one year as effective factors on SOCP. One-way ANOVA were used to determine soil moisture and temperature variability in each treatment through one year, and seasonal dynamics of SOCP were comprised using repeated measures design (General linear model). The SOCP relationship with soil moisture and temperature were analyzed using Pearson correlation coefficient. Results showed that the monthly changes of soil moisture and temperature had a significant difference in each treatment. SOCP was also significantly correlated with soil moisture and temperature. SOCP difference in different seasons was also significant, which was more obvious in the managed treatments. SOCP showed severe decrease in the managed stands compared to the unmanaged stand in the summer

Effect of throughfall and forest floor leachate of beech on base cation dynamics in mixed stand

In forest ecosystems, there is an important interaction between hydrological cycle and nutrient contents. Rainfalls not only have an important role for entrance of nutrient contents to forest ecosystem, but also have an important role to transfer elements from canopy to forest floor and soil. This study performed to investigate the effect of throughfall and forest floor leachate on base-cations dynamics in a mixed hyrcanian beech forest in Golestan province. Throughfall and forest floor leachate samples were taken through 6 months (winter and spring 2008). Amount of base-cations (Ca2+, Mg2+, Na+ and K+) were compared by T-Test between rainfalls and throughfall. Results showed that the amount of Ca2+, Mg2+, Na+ and K+ contents in throughfall were higher than rainfall (

A survey on the accuracy of the inventory method of sample plots with 1000m2 area under random-systematic network for estimation of amount and distribution of stand volume, basal area and tree number in diameter classes

After performing the first and Second 20-years periods of forest projects, even with proper execution of the programs, most of them have many problems yet. One of the most important factors that caused these problems is the method of data preparing and processing. The hypothesis of this research project is “there is a significant difference between the result of random-systematic inventory and full caliper method”. After sampling in plots with 1000 m2 area under a random-systematic grid, correlations between variables were surveyed. Volume, basal area and tree number amount and distributions in diameter classes were compared with the Willcoxon test between the two inventory methods. Conclusions are: data obtained in current random-systematic method in plots with 1000 m2 area have acceptable accuracy just for fuelwood species and hornbeam (Carpinus betulus). For beech (Fagus orientalis) and other species, accuracy decreases with increasing in diameter and heterogen distribution in forest stand

Impact of seasonal variation and tree canopy on density and biomass of earthworm in Brant’s oak (Quercus brantii Lindl.) high forest

Earthworm population, as a biotic factor, affects health and productivity of forest ecosystems. Earthworm density and biomass indicates biological activities and quality of soils. In order to get the benefit of earthworm ecological potential in Zagros forest management, the current biological activities as well as environmental factors impacting of this invertebrate have to be understood. This study aims at determining the density and biomass of earthworm and investigating their relationships to environmental factors including seasonal variability, soil depth and the tree canopy in Brant’s oak (Quercus brantii Lindl.) high forest of Darber area (Khoram Abad, Lorestan). Thirty two single-stem trees of Brant’s oak were sampled. Earthworm’s density and biomass were measured in spring and autumn, under and away from the canopy, using soil profile. Soil profiles were 50 cm deep and samples were taken from layers at 0-10, 10-30, and 30-50 cm depth. Means of earthworm’s density and biomass were compared using one way ANOVA and independent t-test at the 95% probability level. The results of this study showed that seasonal variation, soil layers depth and tree canopy had significant impacts on earthworm’s density and biomass. Earthworm’s density and biomass were decreased in autumn and also in spots away from tree canopy. Minimizing topsoil disturbance and expanding canopy coverage in managing Zagros forest resources could optimize the environmental conditions for earthworm biological activity, which would improve soil quality and ecosystem health

Effect of shelterwood logging on diversity of tree species in the Loveh Forest, Gorgan

In order to identify the effect of shelterwood logging on the species diversity in each stages performance, a study was conducted at the Loveh forest, east of Golestan province. Totally, 117 plots with 60×60m were set down with systematic cluster sampling method at the study area. Diameter at breast height (DBH) of trees and species were assessed in each plot. In this study three managed stands including 20 years practiced stands (shelterwood system), 40 years practiced stands (shelterwood system), and improvement stand as well as one unmanaged stand were compared based on Shannon-Wiener, Smith-Wilson and richness indices. The results of analysis of variances showed that difference among four stands were significant (

Evaluation of Landsat-ETM+ and IRS-LISS III satellite data for forest type mapping in Zagros forests (Case study: Ghalajeh forest, Kermanshah province)

In order to evaluate and compare the capability of ETM+ and LISS III data for forest type mapping in the Zagros forests, a small window of panchromatic and multispectral images of Landsat-ETM+ and IRS-P6-LISS III satellite data were selected from Ghalajeh forests in the Kermanshah province. No radiometric error was found using the quality investigations. Orthorectification of ETM+ was done using 55 ground control points with RMS error of 0.39 for X axis and 0.46 for Y axis and for LISS-III imagery with 34 ground control points with RMS error of 0.67 for X axis and 0.58 for Y axis. Some suitable image processing functions such as principal component analysis, tasseled cap transformation and appropriate vegetation indexes were applied for classification processes. In order to assess the classification results, a sample ground truth was generated using a systematic network with 60m×60m sample area. By computing the canopy cover percent of species, four forest types were determined in the study area. By selecting 25% of samples for each class as training samples, the best band sets were selected using transformed divergence separability index. Classification was performed by supervised method using minimum distance (MD), maximum likelihood and parallel epiped (PPD) classifiers. Results of classification showed that overall accuracy and kappa coefficient for 5 classes for ETM+ images were obtained %44.57 and 0.18 and for LISS III Images %50.6 and 0.32, respectively. After merging the classes of 1 and 2 due to spectral overlapping, the overall accuracy and kappa coefficient for 4 classes using ETM+ images were obtained %61.08 and 0.21 and for LISS III Images, %71.44 and 0.33, respectively. Finally, by merging the classes of 3, 4 and 5, classification was done with two types and the overall accuracy and kappa coefficient obtained %74.1 and 0.37 for ETM+ and %77.7 and 0.41 for LISS III, respectively. Being open canopy cover as well as conflicts between soil and vegetation reflectance caused preventive of obtaining the more favorite results. Result showed fairly more capability of LISS III data in compare to ETM+. Similar research in other regions and using of higher multispectral resolution data is suggeste

Monthly changes in the quantity of throughfall and water infiltration of litter in Hyrcanian forest stands

The canopy architecture of different forest trees results in different species interception, quantity and quality of litterfall. Litterfall characteristics affect thickness of organic layer, water storage potential and runoff due to different decomposition rate in habitat conditions. Furthermore, throughfall content and water infiltration of litter are different through time as a result of differences in the evapotranspiration potential, leaf area index (LAI), canopy coverage, tree diameter, stand stages and other geographic factors. This paper was aimed to examine throughfall and water infiltrated of litter changes amongst three important species of Hyrcanian forest over a year. For this purpose, individual hornbeam (Carpinus betulus L.), velvet maple (Acer velutinum Boiss.) and chestnut-leaved oak (Quercus castaneifolia C. A. Mey.) species were selected in a mixed stand in Shast-Kalateh Forest, and quantity of water passing through the canopy of individual tree and organic litter layer beneath them were investigated with 9 throughfall collectors and 18 forest floor infiltration collectors after each rainfall event over a year. The results showed that species and times are two important factors in changing water balance. The hornbeam and maple species have the most throughfall and litter water contents, respectively (hornbeam with 71.1 % of throughfall and maple with 40.5 % of water infiltration of litter). The litter water infiltration of hornbeam and velvet maple in non-growing season were higher compared to the growing season, while throughfall showed no significant difference. The results of this study are concluded to be helpful for managers to regulate the stand composition as a reaction to the increasing water crisis

Stand structure and spatial pattern of trees in mixed Hyrcanian Beech forests of Iran

Mixed beech forests (Fagus orientalis) are the most important forests with the highest degree of naturalness in Hyrcanian forest of Iran. These forests commonly dominate by shade tolerance species with irregular and uneven-aged stand structure. The aim of this study is to analyze the stand structure and spatial pattern in order to identify specific structural patterns. We studied the stand structure and spatial pattern of trees in mixed beech forest in the Shastkolate Educational Forest to examine the coexistence strategies of different species. Data was collected from a 16.9 ha permanent plot on a 406×416m quadrate area. We measured all trees exceeded than 7.5cm in diameter at breast height on permanent plot. The six main species were divided into two groups based on density and stand structure. Group A had higher density than group B, as well as reverse J shaped DBH distribution of live standing trees. Species in group A have clump spatial distribution pattern in all layers. However, clump intensity is more than in understory and size of patch clump was smaller in this group. This situation for group A may explaining by having numerous coppice, sucker and patch regeneration in the understory layer. Middlestory and understory stems of the six major tree species were patchily distributed throughout the plot. However, for Alder (Alnus subcordata) and Maple (Acer velutinum) common pattern in canopy layer was complete spatial randomness. The distributions of beech trees were negatively associated with other species. These results suggest species differences in favorable canopy condition