Zagros Research Articles

Biogeography of the Iranian snakes.

The events of the Cenozoic era such as mountain formation caused Iran to become one of the most amazing biodiversity hotspots in the world today. This pioneering study on Iranian snake biogeography integrates historical and ecological analyses. A phylogeographic review traces speciation and dispersal, while cluster analysis with a new snake checklist assesses faunistic similarities within Iran and its surroundings. Jaccard and Sorenson indices generate similarity dendrograms, Indicator Species Analysis pinpoints regional key species, and Endemism index calculates regional endemism rates, enriching our knowledge of Iran's species diversity. Phylogeographic analyses identify four biogeographical corridors for snake ingress into Iran: the Arabian region through southwestern Iran, the Western Asian mountainous transition zone via northwestern Iran, the Turanian region into northeastern Iran, and the Indus River Valley into southeastern and eastern Iran. Dendrogram analysis divides snake fauna into three groups. The first group associates western Zagros and Khuzestan fauna with the Sahara and Arabian regions. The second group links Kopet Dagh and Turkmen Steppe fauna with the Turanian region, and Central Plateau and Baluchistan fauna with the Iranian region. The third group connects northwest highlands, Alborz and Zagros mountains, and Caspian Sea coasts with the Western Asian Mountain transition zone. The study validates broad biogeographic patterns via ecoregional associations and indicator species analysis, providing finer resolution. Species like Platyceps najadum in Caspian Hyrcanian mixed forests exemplify ecoregional alignment, while Zagros and Alborz mountains exhibit unique faunal indicators, indicating species-level divergence. Shared indicators among widespread ecoregions reflect habitat continuity; exclusive indicators emphasize regional distinctiveness. Despite endemic species prevalence, they seldom act as significant indicators due to various factors. Our research confirms the Zagros Mountains, Khuzestan Plain, Alborz Mountains, and Persian Gulf coasts as snake diversity hotspots, marked by higher species richness compared to other Iranian regions.

Plant biogeography, endemism and vegetation types of Dena Mts, Zagros, West Iran

Questions: The highest mountain peak of Zagros is located in the Dena mountain system (4409 m a.s.l.), which is identified as the second richest center of plant endemism of Zagros. In this study we (1) investigate floristic affinities of Dena Mts to adjacent mountain ranges based on the endemic species of the Iranian Plateau, (2) identify the species reaching the subnival zone, and (3) characterize the plant communities of the subnival zone of Dena Mts. Study area: Dena Mts is a calcareous mountain system in southern Zagros, Iran. Methods: The list of taxa endemic to the Iranian Plateau present also in Dena Mts was taken from our previously published data. Novel vegetation data were collected using the methodology of Braun-Blanquet. Classification was carried out in JUICE using the Modified TWINSPAN method. Results: Of the 242 taxa endemic to the Iranian Plateau present in Dena Mts, 22 taxa are endemic to the latter. Dena Mts have the strongest floristic affinity with the Yazd-Kerman massif, with which they share 84 taxa compared to 51 taxa shared with Alborz, 37 taxa shared with the Azerbaijan Plateau, and 15 taxa shared with Kopet Dagh-Khorassan. In Dena Mts, 38 taxa reach the subnival zone, most of them being endemic to the Iranian Plateau (68%). From scree habitats in the subnival zone, two new plant associations are described, Aethionemetum umbellati and Zerdanetum anchonioidei. These constitute a newly described alliance Galion pseudokurdici, classified within the class Didymophyso aucheri-Dracocephaletea aucheri. Conclusions: Although Dena Mts lie within a protected area, this will not prevent shrinking of alpine and subnival habitats due to global warming. Consequently, strong attention to the conservation of all range-restricted species of this mountain system, especially of alpine and subnival species, is highly recommended. Taxonomic reference: Flora of Iran (Assadi et al. 1989–2021) and, for families not yet covered in the previous source, Flora Iranica (Rechinger 1963–2015).

Potential Field Imaging of Salt and Basement Structures in the Southern Zagros Foreland Basin

Potential Field Imaging of Salt and Basement Structures in the Southern Zagros Foreland Basin

Albian–Cenomanian echinoids from areas north of Bandar Abbas and south of Fars in the Zagros Mountains, Iran

Fossil echinoids have rarely been described from Iran. This study focuses on the echinoid fauna found in the Cretaceous strata (Kazhdumi Formation) of the Geno and Gerash sections in the Bandar Abbas and Fars areas of the Zagros Mountains, southern Iran. The age of the Kazhdumi Formation in both sections is determined to be Albian-Cenomanian based on the associated ammonites and microfauna, its stratigraphic position, and previous studies on this formation. Twenty-one echinoid species (twelve regular and nine irregular) belonging to seventeen genera were described in this study. Fourteen of these species are reported for the first time from Iran. In addition, a new diadematoid echinoid species, Arabicodidema jafariani sp. nov. is introduced. New age ranges are proposed for Pliotoxaster comanchei and Lambertiaster douvillei. The paleogeographic position of the Zagros Basin in the Tethyan realm is confirmed based on the distribution of the index species.

Selection of the Most Suitable Tree and Shrub Species for the Afforestation of Iranian Northern Zagros Forests Using AHP and TOPSIS Techniques (Case Study: Perdanan Piranshahr)

Selection of the Most Suitable Tree and Shrub Species for the Afforestation of Iranian Northern Zagros Forests Using AHP and TOPSIS Techniques (Case Study: Perdanan Piranshahr)

Identification of fungal species associated with gall oak (Quercus infectoria Oliv.) decline in Iran.

The gall oak (Quercus infectoria Oliv.) tree is one of the most important and valuable forestry species in the Northern Zagros forests in the west of Iran. Gall oak decline is considered to be one of the most important diseases currently affecting the oak Zagros forests in Iran. The main objective of the present study, conducted in the years 2021-2023, was to investigate the possible role of fungi as causative agents of gall oak dieback in the Zagros forests of Iran. Wood samples were taken from gall oak trees showing canker, dieback, and internal wood discoloration symptoms. Fungal isolates recovered from gall oak trees were identified based on cultural and morphological characteristics, as well as phylogenetic analyses using DNA sequencing of the internal transcribed spacer region of rDNA (ITS) and partial beta-tubulin (tub2). Achaetomium aegilopis, Alternaria tenuissima, Apiospora intestine, Botrytis cinerea, Coniochaeta sp., Coniothyrium palmarum, Coniothyrium sp., Cytospora rhodophila, Dialonectria episphaeria, Diatrype sp., Diatrypella macrospora, Endoconidioma populi, Fonsecazyma sp., Fusarium ipomoeae, Jattaea discrete, Kalmusia variispora, Microsphaeropsis olivacea, Neoscytalidium dimidiatum, Paecilomyces lecytidis, Paramicrosphaeropsis eriobotryae, Paramicrosphaeropsis ellipsoidea, and Seimatosporium pezizoides were identified from diseased trees. Pathogenicity tests were performed by artificial inoculation of excised branches of healthy gall oak trees under controlled conditions and evaluated after 35 days by measuring the discolored lesion length at the inoculation site. N. dimidiatum was the most virulent species and caused the longest wood necrosis within 35 days of inoculation. In the greenhouse test, only some species induced typical symptoms of canker. All isolated fungi are reported for the first time on gall oak trees in the world.

Identifying the most effective climate parameters on crop yield in rain-fed agriculture and irrigated farming in Iran

Agriculture is an industry that has been traditionally used in Iran to meet people's daily nutritional needs. Since crops are affected by climate change, finding the best location to grow crops will improve crop yields. The Geographical Detector Model (GDM) was adopted in this study to measure the effects of four climate parameters, i.e., precipitation, temperature, humidity, and evaporation, in different seasons of the year on the yields of barley, beans, lentils, chickpeas, rapeseed, and wheat across Iran. According to the results showed, the highest crop yields across Iran come from wheat and barley. Furthermore, the yields of most crops are reduced in rain-fed agriculture, as the yield of wheat in rain-fed agriculture decreases by nearly 70% as opposed to irrigated farming. According to the findings, EA, ESU and EW with 24, 22 and 19 percent has more affected to barley. Rising temperatures to more than 26.1 °C can cause a sharp decrease in crop yields, with some crops yielding less than 0.5 tons/ha. The results also showed that wheat thrives more effectively in regions characterized by cold and extremely cold winters, where temperatures ranging from −3.5 to 0.98 yield an average of 3.88 tons per hectare in irrigated agriculture, while rainfed farming shows a recorded figure between 3.6 and 4.7 at 1.08. Provincial assessments indicate that temperature and precipitation are the key factors influencing crop productivity in regions characterized by cooler temperatures and higher rainfall. Specifically, the peak barley yield in irrigated areas was observed with spring rainfall exceeding 153 mm. Conversely, in tropical provinces with limited rainfall, humidity and evaporation emerge as the primary determinants of crop yields. In these regions, the highest barley yields were noted where evaporation levels surpassed 227 mm. Moreover, provinces located on the slopes of the Alborz and Zagros mountains are the best locations for wheat and chickpea cultivation, and the southeastern regions of Iran are not suitable for barley and lentils. The findings of this research have significant implications for water resource management, facilitating the identification of cultivation patterns across diverse climatic conditions and enhancing strategies for crop yield optimization.

Amphibian hotspots in Iran: Effectiveness of current protected area and priorities for conservation planning

The identification of conservation priority areas for amphibians in Iran remains unexplored. Although protected areas play a vital role in biodiversity conservation, 40 percent of amphibians are at risk of extinction. The present study aimed to identify the priority areas for amphibian conservation and assess the effectiveness of the current protected conservation areas. 2192 species occurrence points for 23 amphibians, including 16 species of Anura and 7 species of Caudata, were curated. These occurrence points in addition to bioclimatic, anthropogenic, and geographical variables were used to model the species distribution. Then, the richness and rarity maps of amphibians were determined and hotspots identified based on the top 10 % area of the country with the highest richness and rarity values. Finally, Iran's protected areas were overlaid to evaluate the current coverage of hotspots and identify future conservation priorities. Although approximately 12 % of Iran is currently protected, the present study findings indicate that the current network of protected areas is ineffective for amphibian conservation; over 90 % of hotspots for amphibians lie outside the current national protected area network. The most important hotspots are located in the Caspian Hyrcanian Mixed Forest, the western margin of the North Zagros, and the Central Zagros Mountains Forest-Steppe ecoregions of the country. Among different types of protected areas that overlap with amphibian hotspots, protected areas and wildlife refuges respectively ranked the highest in quantity and size, while national parks ranked the lowest. In the current study, a baseline of top candidate areas for expanding protected areas where habitats can be managed to protect amphibians in Iran was provided. To further improve protected areas' coverage, priority conservation areas in the Zagros Mountains Forest-Steppe hotspots were recommended.

Unveiling the Role of Climate and Environmental Dynamics in Shaping Forest Fire Patterns in Northern Zagros, Iran

Wildfires present a major global environmental issue, exacerbated by climate change. The Iranian Northern Zagros Forests, characterized by a Mediterranean climate, are particularly vulnerable to fires during hot, dry summers. This study investigates the impact of climate change on forest fires in these forests from 2006 to 2023. The analysis revealed significant year-to-year fluctuations, with notable fire occurrence in years 2007, 2010, 2021, and 2023. The largest burned area occurred in 2021, covering 2655.66 ha, while 2006 had the smallest burned area of 175.27 ha. Climate variables such as temperature, humidity, precipitation, wind speed, heat waves, and solar radiation were assessed for their effects on fire behavior. Strong correlations were found between higher average temperatures and larger burned areas, as well as between heat waves and increased fire frequency. Additionally, higher wind speeds were linked to larger burned areas, suggesting that increased wind speeds may enhance fire spread. Multiple linear regression models demonstrated high predictive accuracy, explaining 84% of the variance in burned areas and 69.6% in the variance in fire frequency. These findings document the growing wildfire risk in the Northern Zagros region due to climate change, highlighting the urgent need to integrate scientific research with policies to develop effective wildfire management strategies for sustainable forest management.

Reconstructing contact and a potential interbreeding geographical zone between Neanderthals and anatomically modern humans

While the interbreeding of Homo neanderthalensis (hereafter Neanderthal) and Anatomically modern human (AMH) has been proven, owing to the shortage of fossils and absence of appropriate DNA, the timing and geography of their interbreeding are not clearly known. In this study, we applied ecological niche modelling (maximum entropy approach) and GIS to reconstruct the palaeodistribution of Neanderthals and AMHs in Southwest Asia and Southeast Europe and identify their contact and potential interbreeding zone during marine isotope stage 5 (MIS 5), when the second wave of interbreeding occurred. We used climatic variables characterizing the environmental conditions of MIS 5 ca. 120 to 80 kyr (averaged value) along with the topography and coordinates of Neanderthal and modern human archaeological sites to characterize the palaeodistribution of each species. Overlapping the models revealed that the Zagros Mountains were a contact and potential interbreeding zone for the two human species. We believe that the Zagros Mountains acted as a corridor connecting the Palearctic/Afrotropical realms, facilitating northwards dispersal of AMHs and southwards dispersal of Neanderthals during MIS 5. Our analyses are comparable with archaeological and genetic evidence collected during recent decades.

Active strike-slip faulting, diapirism and seismic hazards. The case of the Kareh Bas fault and the associated Dandenjan salt extrusion in the zagros Mountains, SW Iran

Strike-slip salt diapir systems have been scarcely investigated and have probably been underrecognized. The western Fars Arc of the Zagros Mountains hosts the most remarkable example of salt extrusions associated with seismogenic strike-slip faults within an oblique collisional setting. This study, mainly based on field mapping and observations carried out in the Kareh Bas fault system and the Dandenjan Diapir, explores several issues with practical implications related to these active fault-salt systems: (1) role of precursor diapirs on the initiation of shortening structures; (2) fault segmentation controlled by precursor diapirs, emergence of diapirs, and the development of pull-apart basins; (3) the relative timing of emergence of salt extrusions associated with a propagating strike-slip fault; (4) Quaternary deformation and paleoseismic evidence associated with the Kareh Bas fault; (5) the impact of the salt detachment depth on the seismogenic potential of the segmented Kareh Bas fault system; and (6) clustering of large potentially coseismic landslides in the vicinity of the Kareh Bas fault system.

Increasing drought frequency in the central Zagros Mountains of western Iran over the past two centuries

The Zagros region in western Iran has experienced prolonged drought, significantly impacting water resource and forest ecosystems over the past few centuries. Understanding historical prolonged drought is crucial for making precise forecasts of shifts in regional drought in the Zagros region. Due to the lack of comprehensive historical records, the use of proxy records is considered a valuable tool for reconstructing past drought variations. We aimed to construct a tree-ring chronology of Juniper (Juniperus polycarpus) in the central Zagros region to comprehend its growth response to climate variables. We cored 25 J. polycarpus trees from the Keygooran forest reserve in western Iran and developed the tree ring chronology (1802–2022) using dplR. The relationships between tree growth and climate variables of monthly mean temperature, precipitation, PDSI (Palmer Drought Severity Index), and SPEI (Standardized Precipitation Evapotranspiration Index) were examined. The analysis revealed a strong positive correlation between tree growth and SPEI March-September of 1990–2018 on a 48-month timescale with a 2-year lag (r = 0.61, p < 0.05) which was included in the transfer model. Consequently, the SPEI-48 March-September was reconstructed for the period 1802–2022. On this reconstruction, several extremely dry years in 1832, 1867, and 1876 and extremely wet years in 1807, 1814, 1838, 1850, 1907, and 1908 years were identified, some of them aligning with historical records in Iran. Furthermore, there was a relationship between SPEI-48 March-September and teleconnection events suggesting that certain drought occurrences in the area were associated with the El Niño-Southern Oscillation (ENSO). Consequently, this reconstruction can serve as a reliable proxy for large-scale drought variability in the Zagros region of western Iran. Moreover, our research underscores the utility of SPEI in reconstructing the history of semi-arid climate conditions.

Contextualizing wild cereal harvesting at Middle Palaeolithic Ghar-e Boof in the southern Zagros

A stratigraphic sequence from Ghar-e Boof, a cave site in Iran, covering a period of c. 80,000–30,000 BP and containing more than 20,000 seed and chaff remains, allows a detailed study of the use of annual seed species of Palaeolithic hunter-gatherer groups and its evolution under the influence of changing environmental conditions. Taxonomic changes in the archaeobotanical assemblage and the stable carbon isotope data of pistachio support a considerable change in environmental conditions over the sequence from MIS 5a to MIS 3. The exceptional dominance of wild ancestors of modern crop species, including glume wheat and large-seeded legumes from Middle Palaeolithic layers AH VI (OSL ranges 72–81 ka BP), coincides broadly with the transition from MIS 5a to MIS 4. With the beginning of MIS 4 these taxa are strongly reduced, corresponding with a strong decrease in global CO2 concentrations and in the Δ13C values of Pistacia khinjuk/atlantica from the site. Wild glume wheat completely disappears after Middle Palaeolithic AH Vb and never reappears at the site. We hypothesize that the Middle Palaeolithic niche that allowed the harvesting and consumption of wild cereals and legumes ended with a destabilization of the vegetation in early MIS 4.

The link between gas extraction and shallow seismicity around the Dalan gas field of Zagros Mountains, Iran

We analyze seismicity from 2013 to 2023 near Bushkan village in the Fars arc of the Zagros folded belt, colocated with the Dalan natural gas field. A previous study suggested unusual seismic behavior in the 2014–15 cluster, linking larger events to shallow depths (∼5 km) on steep reverse faults within the Dalan anticline. Nevertheless, ongoing debates persist regarding the potential correlation of seismicity with activities in the Dalan field. Our study investigates seismic activities using relocation, moment tensor inversion, stress inversion, and remote sensing techniques. We relocated 35 events above magnitude 3 and reconstructed source parameters for 12 events (M 4+) with uncertainties. Focal mechanisms were inverted, and morphology remote sensing was employed to ascertain the active stress state. Besides the 2014–15 cluster, we found a separate strike-slip cluster in 2018 at shallower depths (3–4 km), unusual for Zagros earthquakes. We suggest that pore pressure variations influence seismic sequences in the Dalan gas field area. However, distinguishing between human-induced and natural earthquakes in regions like Zagros with naturally elevated seismicity is challenging.

Phylogenetic climatic niche evolution and diversification of the Neurergus species (Salamandridae) in the Irano-Anatolian biodiversity hotspot.

This study explores how climate variables influenced the evolution and diversification of Neurergus newts within the Irano-Anatolian biodiversity hotspot. We use a dated phylogenetic tree and climatic niche models to analyze their evolutionary history and ecological preferences. Using genetic data from nuclear (KIAA) and mitochondrial (16s and 12s) genes, we estimate divergence times and identify four major Neurergus clades. The initial speciation event occurred approximately 11.3 million years ago, coinciding with the uplift of the Zagros and Anatolian mountains. This geological transformation isolated newt populations, likely triggering the first speciation event. By integrating potential geographic distribution with climate variables, we reconstruct ancestral niche occupancy profiles. This highlights the critical roles of temperature and precipitation in shaping Neurergus habitat preferences and distribution. We observe both phylogenetic niche conservatism and divergence, with niche divergence playing a dominant role in diversification. This research emphasizes the complex interplay of geography, climate, and ecology in speciation and the vulnerability of isolated mountain newt populations to environmental changes.

A contribution to the knowledge of the genus Niphargus (Arthropoda: Crustacea: Amphipoda) in northwestern Iran

Niphargus Schiödte, 1849 is the most diverse subterranean amphipod genus in the West Palearctic, distributed between Ireland and Iran. The exploration of Niphargus diversity in the Zagros Mountains in Iran has begun a decade ago, and the number of newly described species is increasing fast. Recently, we collected several specimens of Niphargus from springs located in the northern parts of the Zagros Mountains in Iran. Detailed morphological observations and molecular phylogenetic analyses using 28S rDNA and COI markers revealed that these animals comprise two taxonomic units distinct from all hitherto described species. We hypothesize they should be treated as new species, named as Niphargus qalatianensis sp. nov. and Niphargus arasbaranensis sp. nov. Molecular phylogenetic analyses have shown that N. qalatianensis sp. nov. is nested within a monophyletic Middle Eastern clade known from previous studies. By contrast N. arasbaranensis sp. nov., is with low support associated to European species and suggests that the Iranian karst was not colonized two but three times. To gain a more comprehensive understanding of the intricate biogeographical history of the genus Niphargus in the Middle East, additional sampling in the region is imperative.

Archaeometric analysis of pottery sherds from Barveh Tepe: Insights into Early Bronze Age pottery‐making techniques and firing temperatures

AbstractBarveh Tepe, an archaeological site from the Early Bronze Age in the Zagros Mountains of Iran, was the focus of an archaeometric analysis in this study. The aim was to evaluate the firing temperature of excavated pottery sherds from Barveh Tepe and to gain insights into the pottery‐making techniques employed. A range of analytical methods, including optical microscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) with energy‐dispersive X‐ray spectroscopy (EDS), thermal gravimetric analysis (TGA) and X‐ray diffraction (XRD), was utilized to characterize the pottery sherds. The results revealed the utilization of two primary types of raw clays: calcite‐rich (calcareous) and calcite‐poor (non‐calcareous). The presence of calcite in calcareous pottery samples was confirmed, with the calcareous pottery showing a low CO3−2 vibrational band, indicating a low firing temperature. Through the integration of SEM images, FTIR spectra, TGA curve and XRD pattern results, the estimated firing temperature range for Barveh Tepe pottery was determined to be between 600 and 1100°C. These findings provide new insights into the pottery‐making practices of the Early Bronze Age and shed light on the technological advancements of the period.

Bufonia darvishii (Caryophyllaceae), a novel endemic species from Zagros Mountains, Iran

A new subalpine species of Bufonia sect. Longipedicellata from the Zagros Mountains in west Iran is described and illustrated here. It colonizes mountain slopes with gravelly, stony, and scree substrates in one locality of Chaharmahal and Bakhtiari province, preferably with a western and north‐west orientation, at elevations between 2700 and 3100 m a.s.l. The new species, B. darvishii, is diagnosed against the morphologically similar B. macrocarpa. The two species share similarities such as filiform and long pedicels, a lax panicle‐cyme inflorescence, distribution pattern of trichomes, and long peduncles. However, the new species stands out with semi‐shrub life form, its greater height, retention of the previous year's stems, cymes bearing more flowers, orbicular petals, larger petals, a broadly ovate ovary, larger sepals with more pronounced nervation, shorter pedicels, larger flowers, etc. Bufonia darvishii is proposed to be Critically Endangered (CR) following the guidelines of the IUCN.

The Palaeozoic of a future high potential hydrocarbon fold-thrust belt through the Zagros Basin, Iran

The Zagros Fold-and-Thrust Belt is one of the world's richest hydrocarbon regions, with Palaeozoic sediments being a key element in hydrocarbon plays. The main aim of this research is to provide a model for the formation and development of the sedimentary basin during the Palaeozoic Era in the Zagros and Persian Gulf regions. We utilize data from exploratory wells and surface outcrops of Palaeozoic sediments specifically in the northern parts of Iran's Zagros Mountains. The seismic profiles of the eastern region of the Persian Gulf provide more detailed information due to their distance from the Zagros hinterland. The investigation reveals that folds with wavelengths of several tens of km were formed on the Infra-Cambrian Hormuz Salt or its equivalent décollement.This study has identified halokinetic activities as the primary cause of Palaeozoic deformations in the Zagros region, with tectonic and orogenic factors playing a secondary role. The Palaeozoic sediments are divided into pre-kinematic, syn-kinematic and post-kinematic categories. Sedimentary sequences possibly including the Palaeozoic hydrocarbon source rock could be present throughout the study area.

New data on distribution of Phoenicurusia transcaucasicus (Miller, 1923) (Lepidoptera, Lycaenidae) with description of a new subspecies from Iran

Distribution of Phoenicurusia transcaucasicus (Miller, 1923) in Iran and neighbouring territories is clarified based on analysis of DNA barcodes, the male genitalia and wing pattern of adults. Our study revealed the widespread distribution of Ph. transcaucasicus throughout northern, northeastern and central Iran. Based on integrative analysis, a new subspecies, Ph. transcaucasicus flamma ssp. n., is described from the Zagros Mountains, the Central Iranian Range and the Alborz Mountains. Compared to the nominotypical subspecies, the new subspecies differs in well-developed orange pattern both of dorsal and ventral sides of the wings, shape of the valva in the male genitalia and distinct COI haplotypes. Additionally, distinct phylogenetic lineage of Ph. transcaucasicus is reported from Kerman Province. Diagnostic characters of the species of Ph. phoenicurus (Lederer, 1870) group of Iran are illustrated.