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ŠUMARSKI LIST 3-4/2017 str. 19     <-- 19 -->        PDF

or more, were selected. In order to reduce the slope-related errors, the study was started on the lands with 5-10% slope, and the study areas were distributed in accordance with the aim of this study (in dimensions of 10m x 10m) to various altitude, exposure and vegetation height levels. Since the factor of slope is not a factor that affects the biomass storage capacity of maquis vegetation, it wasn’t involved in experimental design. In studies on sloping lands, it is required to determine a correction factor and recalculate the edge lengths in order to accurately find the limits of sample plots. In order to prevent the error possibility and time loss that these calculations for each of 4 edges would lead, the sampling procedure was executed on the lands having up to 10% slope. By examining the actual statuses of the lands, firstly the alive, healthy and robust individual populations were considered.
In order to determine the aboveground biomass, all of the individuals within the each plot area were clear-cut at the closest point to the soil level and the branches were weighed. Besides that, the stem sections were taken from 3-5 individuals at the closest point to the soil level in order to determine the age.
In order to determine the belowground biomass, the distribution of individuals within the plot areas; in every sampling point, a 2mx2m section was dug down to the bedrock, and then the roots were taken out and weighed. Fine root (thinner than 2 mm) sampling was not performed, and they were excluded from assessment.
Samples were taken from every component. Wood samples were peeled from barks, and fresh wood and bark weights were measured. In order to determine the weight of leaves, the sample branches were taken and, by separating the leaves, the weights of leaves and branches were measured, and then compared in order to estimate the ratio. And then, the samples were taken to the laboratory and completely dried at 65±3°C temperature and their dry weights were found. Using fresh/dry weight ratios, the fresh weight values were translated into dry weight values. Although the most widely accepted method for determining the moisture content of wood is to dry in an oven at 105°C, the removal of volatile content at this temperature may lead to errors in estimating the moisture content (Rodriguez 1998, Granstrom 2003). Plant biologists generally dry the leaves and fruits at 60-70 °C, because high temperatures cause decreases in organic compounds (Westerman, 1990). Cornelissen et al. (2003) have recommended drying the herbaceous stems at 60 °C for 72 hours or at s 80 °C for 48-72 hours, and extended this recommendation to woody stems. Since maquis societies consists of high-level of leaves and thin material, the temperature of drying was set to 65°C in order to prevent any failures due to high temperature.
The analyses of data were performed in accordance with the design of study. While designing, in order to reveal the maquis’ biomass, 4 groups of samples, which were believed to have effect on the biomass, were established, and then they were divided into sub-groups. And then, by using t-test and variance analysis, it was examined if there are differences between these sub-groups.
Firstly, the variation of among the altitude steps of study area, where the maquis spreads, and the ratio of participation into composition were determined. It was observed that there were significant difference between the species and the ratio of participation into composition of the components constituting the maquis as the altitude changed. While Quercus coccifera L. individuals were observed at all the altitudes between 488m and 1115m, Quercus coccifera L.’s ratio of participation into composition increased as the altitude increased, and it became a maquis population consisting of a single species at the highest altitude level. Moreover, in and around every plot area, the Juniperus drupacea (Labill.) individuals were separately observed. While Phillyrea latifolia L. species was found to be the species that was most frequently observed up to 1000m altitude, it was replaced by Quercus coccifera L. at higher altitudes. In Table 1, the change of species can be seen in 250m of altitude intervals.
Although the maquis vegetation varies between 0m and 1250m altitudes throughout the study area, the populations, where the sampling could be performed, were found at 488-1155m of altitudes. 35 sample plots taken among those altitudes were divided into 4 sub-groups, 200m each, and the amounts of biomass they stored are presented in Table 2 in mean values.
As a result of the evaluation by considering the biomass storage capacities of the groups, the most significant difference was observed in root wood and root bark. While the portion of aboveground biomass is higher between 400m and 600m altitudes, belowground biomass was observed to be higher than aboveground biomass in all the resting sub-groups. While no altitude-related difference was observed in maquis populations constituting the aboveground biomass,