جستجوی مقالات مرتبط با کلیدواژه « بندپایان » در نشریات گروه « جنگلداری »

This study aimed to determine the efficiency of numerical and parametrical indices to evaluate biodiversity of soil and litter mesofauna in different physiographic positions. Sampling was conducted in three height classes above sea level (low land, middele land and high land) and two aspects (north and south). Also, in each altitude class, three different slope classes (less than 25%, 50-25% and more than 50%) were determined. Three transects of about 100 m were established in each of the slope classes. Three sample points were located along each transect. Around the center of each sample point, a litter layer and a soil sample to a depth of 10 cm speratly were taken. In the laboratory, soil and litter samples were placed inside a Berlese funnel to bring out arthropods mesofauna. The results showed that soil mesufauna Shannon–Wiener's diversity, Pielou's evenness and Margalef's richness indices, were significantly affected by aspect, elevation, sampling depth and their interactions. Along the northern aspect and in the litter layer, the highest Shannon–Wiener's diversity index was observed in middle land and slpoe

In this study, the abundance and biomass of soil macrofauna were investigated in natural forests of tamarisk and Euphrates poplar in riparian forests of Maroon River in Khuzestan province. Soil macrofauna were collected using 175 sampling plots 50 meter distance from each other on 21 parallel lines with 100 meters distance from each other and perpendicular to the river. Soil macrofauna sampling were taken using hand-sorting procedure in the 50 × 50 cm plots from of 0-10 cm depth. Number of trees, percent of total crown cover, percent of Euphrates poplar and Tamarisk crown cover, height of tree crown cover, total height, Diameter at breast height and Crown diameter of nearest Euphrates poplar and Tamarisk to macrofauna plot, distance of nearest Euphrates poplar to macrofauna plot, distance of nearest tree to macrofauna plot and distance of plot to the tree with the highest diameter in the plot. Results showed that earthworm abundance and biomass have significant correlation with number, percent of crown cover, crown height, total height, diameter and crown diameter of nearest Euphrates poplar tree. Arthropod abundance had significant correlation with number, percent of crown cover, crown height, total height, diameter and crown diameter of nearest tamarisk tree. Therefore it could be concluded that tamarisk and Euphrates poplar were respectively correlated with arthropod and earthworm. The CCA predicted 11.9 percent of total changes of macrofauna. As the three factors of number, crown cover and diameter of nearest Euphrates poplar had the most significant influence on the soil macrofauna distribution in this area, it could be approved that Euphrates poplar have more influence on soil macrofauna distribution.

Populus euphratica Oliv. forests in river floodplains of Khuzestan province are degraded heavily. Tree plantation is one of the methods for restoration of these degraded sites. The plantations of Eucalyptus camaldulensis, Acacia salicina and Dalbergia sissoo were established in randomized complete block design in 1993 with three replications along Dez river. Soil macrofauna were collected by hand sorting, using two randomly located 0.25m2 sampling frames at each plot. All macroinvertebrate organisms (macroscopic organisms) in litter and mineral soil up to 25cm, were collected. Totally, 18 samples were collected. In these treatments, earthworm constituted the largest part of soil macrofauna. Earthworm abundance and biomass were highest in Acacia plantation whereas Arthropods did not show any significant differences. Since soil macrofauna was dominated with earthworm, its variations are in line with earthworm. The abundance and biomass of earthworm and soil macrofauna were negatively correlated with the C/N ratio. Lower earthworm abundance and biomass under Eucalyptus plantation could be as a result of its leaf phenolics or soil nitrogen limitation. Totally, it could be concluded that different tree species had various effects on soil macrofauna (especially earthworm) abundance and biomass. As Acacia species increased the soil macrofauna and improved soil fertility, it could be preferred species for plantation in this area.