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In a survey on soil nematode fauna of northwest and north of Iran, one undescribed and three known members of the genus Talanema Andrássy, 1991 were collected. The nematodes were identified based on morphological and morphometrical characters. Talanema saccatum sp. n. collected from soil around roots of almond trees in Sufiyan, East Azarbaijan province, is characterized by its 1.20–1.53 mm long body, lip region nearly angular, more than twice of its height, 14.0–17.0 μm wide, odontostyle 18.0–20.0 μm or 1.1–1.5 times the lip region diam., odontophore 26.0–29.0 μm long, vulva transverse slit at 53.0–56.0% of body length, prerectum 1.4–2.4, rectum 1.0–1.2 anal body diam. Long, tail 24.0–31.0 μm (c = 42.0–54.0 and c′ = 0.8–1.0), with digitate terminus and rounded tip, ventrally nearly straight, with numerous saccate bodies mostly in ventral side and sometimes on both sides. Herein, Talenema avolai Vinciguerra and Clausi, 1994, Talanema pararapax (Ahmad and Jairajpuri, 1982) Andrássy, 1991 and Talanema sphinctum (Mohilal and Dhanachand, 2001) Imran et al., 2021 are also reported as new records of this genus from the country. An updated identification key for all species is also provided. [ABSTRACT FROM AUTHOR]

The objective of this study is to determine soil fauna of the superfamily Chalcidoidea (Hymenoptera) captured by Berlese funnel from northwest and south of Iran during 2014 and 2015. Our examination of found Chalcidoidea leads us to introduce seven species from four families of Chalcidoidea. These species include two Chalcididae: Proconura sp. 1 and Proconura sp. 2; two Eulophidae: Astichus arithmeticus (Förster), Elachertus charondas (Walker); one Mymaridae: Camptoptera papaveris Förster and two Pteromalidae: Dipara sp. and Ksenoplata quadrata Boucek. Of which, the subfamily Diparinae and the genus Dipara, also three species Astichus arithmeticus, Elachertus charondas and Camptoptera papaveris are new records for Iran. [ABSTRACT FROM AUTHOR]

Soil biodiversity includes organisms which spend a part or all of their life cycle on or in the soil. Among soil-dwelling animals, macro-fauna as an important group of animals have important effects on the dynamics of soil organic matter and litter decomposition process. The humus forms interact with the climatic conditions, flora, as well as soil fauna, and microbial activity. In new humus form classifications, soil organisms play an important role in separation of humus horizons from one another. The subject of this study was to determine the diversity of macro fauna for different humus forms. We determined humus forms using morphological classification, and then 69 random samples were taken from plots of 100 cm in area, and soil macro-fauna species were collected by hand sorting method. Two classes of humus forms, including Mull (with three humus orders, namely Dysmull, Oligomull, and Mesomull,) and Amphi (with four humus orders, namely Leptoamphi, Eumacroamphi, Eumesoamphi, and Pachyamphi) were identified. A number of 13 macro-fauna orders were identified using identification key. Among the humus orders, Shannon diversity, Simpson evenness and Margalef richness indices were the highest in Pachyamphi order. Arthropod diversity in Pachyamphi humus order was higher than those of Mull. These results showed that diversity of soil macrofauna increase by increasing the thickness of the organic horizons (OL, OF, OH), especially OH horizon. [ABSTRACT FROM AUTHOR]

Anthropogenic fires have varying effects on the oak-dominated forests of the Zagros Mountains in western Iran. The objective of this project was to investigate the effects of fire on various components of soil. For this purpose three homogeneous and neighboring sites were inspected. Site A was the unburned control. Sites B and C experienced fires about 2 and 8 years prior to the study, respectively. In comparison to the control, site B showed a decline in organic matter content (1.69 ± 0.24 vs. 1.13 ± 0.17), N amount (0.40 ± 0.05 vs. 0.19 ± 0.03), litter depth (1.20 ± 0.214 cm vs. 0.087 ± 0.044 cm), germinated seedlings (272 ± 40 vs. 75 ± 25), earthworm biomass (3.4 g/kg vs. 0.26 g/kg), and plant diversity (1.95 ± 0.30 vs. 1.35 ± 0.34). An increase was observed for pH (7.41 ± 0.11 vs. 7.72 ± 0.15), Ca (569.09 ± 34 vs. 855 ± 38.17), bulk density (1.17 ± 0.05 vs. 1.66 ± 0.18), the number of arbuscular mycorrhiza (AM) spores, and stump sprouting (1645 ± 533 and 3425 ± 491). Site C showed a similar decrease in organic matter content, N amount, litter depth, germinated seedlings, and earthworm biomass. However, plant diversity was greatly increased at site C, demonstrating that the conditions were better for plant life 8 years after the fire event. Thus, the number of germinated seedlings was lower than that of the control, while stump sprouting (4170 ± 452 per ha) was the greatest. The AM spore count was higher at site B in comparison to site C, indicating that fire had caused a long-term loss in this essential component of the soil. An increase in pH was a characteristic feature of the burnt sites. Levels of macronutrient K were greatly increased at site C. In fact, K content was much higher than the other two sites (A, B, and C: 51.81 ± 3.69, 59.75 ± 8.18, and 72.55 ± 20.66, respectively), indicating that increased K content is a long-term effect of fire. Bulk density (1.80 ± 0.14) increased at site C, which may be due to the insufficient earthworm biomass. Thus, 8 years were not enough to improve the soil conditions for soil fauna. [ABSTRACT FROM AUTHOR]

The effect of vegetation types at mountainous sites on the relationships between soil biota and environmental variables applicable for the evaluation of soil quality and functions are barely studied and remain almost unknown. In the present study, the effect of forest degradation and vegetation types changes [i.e. natural forest with dominant species of Zelkova carpinifolia (Pall.) K. Koch. and three rangelands with dominant species of Festuca ovina L. Dactylis glomerata L. and Stachys byzantina K. Koch.] on the dynamics of soil properties and density of soil organisms in northern Iran has been considered. For each studied vegetation types, three different sites (at a distance of 4–6 km) with 1 ha area were selected. In summer (August), litter or O-horizon (i.e. L, F, and H) and soil (0–10 cm) layers were collected in an area of 30 × 30 cm. Also, in order to study the dynamics of soil properties, in addition to summer, soil samples were collected in the spring (May) and autumn (November) in each of the habitats. The study area is commonly covered with snow from late December to early April every year and therefore soil sampling was not considered in the winter season. A total of 48 litters (12 samples for each of those studied vegetation types), in the summer, and a total of 144 soil [(4 vegetation types × 3 seasons × 12 samples)] samples were collected and transferred to the laboratory. According to our findings, with higher values in the autumn season, the highest density of the soil earthworm (epigeic, anecic and endogeic), microarthropods (Acarina and collembola), nematode, and protozoa were detected in the Zelkova vegetation soils. Also, the highest density of bacterial and soil fungal communities were observed, especially in summer, under the tree cover of forest habitat. Based on our data, forest degradation and vegetation type changes suppressed the density of soil biota ranked in Zelkova > Festuca > Dactylis > Stachys due to low quality of litter, soil climate, and fertility condition. Although each vegetation type plays a prominent ecological role, forest covers are worthwhile because of their capacity to create hotspots identified by soil fauna and flora densities, which play a key role in the nutrient cycle and ecosystem services, in mountain habitats. [Display omitted] • Vegetation type affect litter properties in semi-arid ecosystems of northern Iran. • Conversion of forest to rangelands suppressed the densities of soil biota. • Soil fauna showed higher densities in the autumn season. • Highest density of soil flora were observed in the summer season. • Forest covers created hotspots identified by soil biota in mountain habitats. [ABSTRACT FROM AUTHOR]