species diversity

The study aimed to assess temporal and spatial variations in the population of polychaetes, a significant invertebrate group in deep-sea ecosystems, across the northern waters of the Persian Gulf and the Oman Sea. Sampling occurred from fall 2018 to winter 2020, covering regions in Hormozgan, Bushehr, Sistan and Baluchestan, and Khuzestan. A total of 115 stations were surveyed, utilizing 0.1 square meters and a 500 μm sieve (repeated thrice) to collect bed sediments within the depth range of 12 to 90 meters. Within this study, 35 species/genus of polychaetes were identified in the waters of the Persian Gulf and the Oman Sea. Notably, Flabelligra sp., Manayunkia aestuarina, and Glycinde sp. exhibited the highest abundance, with Flabelligra sp. and M. aestuarina serving as indicator species in both regions. The provinces of Sistan and Baluchestan and Bushehr displayed the highest Shannon diversity and species richness, recording 3.592 and 6.998, respectively. Comparing these findings with prior reports revealed a reduction in the diversity of identified polychaete species in the Persian Gulf. This decline could stem from various factors such as habitat damage due to fishing equipment, and the incidence of contaminants. Continual research and database establishment for time series analysis could significantly aid researchers, authorities, and environmental advocates in comprehending the health status of the Persian Gulf and the Oman Sea. Such efforts would facilitate environmental monitoring and pollution prevention measures, contributing to the preservation of these ecosystems

Habitat is one of the key parameters for species conservation. The first step for habitat management is to determine the factors affecting the distribution of species and species diversity.Plants, as the most stable and important organisms in any habitat, provide shelter and food for animal organisms and play an important role in life cycles. This research was conducted through field visits, interviews and the use of available statistics from the Wildlife Census in the year 2021. Some information on small mammals and plant type of Shirkuh no-hunting area was available from previous studies. There were 30 species of mammals and 19 species of plants in the Shirkooh Wildlife refug .The highest number of mammals was seen in the type (Artemisia sieberi- Noaeae mucronata- Stipa barbata). The number of species and the amount of richness indices in the species (Artemisia aucheri- Astragalus spp- Stipa barbata) was higher than other types. The results of Kruskalovalis test showed that the number of mammals, number of species and also the amount of Man-Henic index at the level of 0.01% and indices of species diversity and Alatalo at the level of 0.05% are significantly different from plant types. The pattern of distribution of animal species richness in large scale and in arid climate is influenced by various environmental factors and in this region the plant type, direction and latitude has been one of the important factors. The great diversity of plant types (type 19) has caused the richness of mammals in the region.

The present study was conducted to investigate the effects of physical factors on the diversity of species of Carabidae (Coleoptera: Carabidae) in three regions of Karaj, Eshtehard, and Taleghan, Alborz province. To this end, during 2015-2016, sampling was carried out using pitfall traps and physical factors. In this regard, the elevation, slope, direction, precipitation, temperature, soil texture, grain size of soil, and percentage of vegetation were recorded in each studied station. Based on the results, in total, 329 specimens including 38 species were identified in the three studied areas. Pearson and Spearman tests were used to investigate the relationships between the species diversity index (Shannon's Diversity Index) and the studied factors. Also, the effect of habitat physical parameters on the diversity of the species of Carabidae in the studied areas was analyzed using Canonical Correspondence Analysis (CCA). The results of the study showed that no significant relationship between the Shannon-Wiener Index and studied parameters (P<0.05). Species diversity was affected by temperature, the three parameters of altitude, soil texture, and grain size of soil, and the four parameters of direction, slope, precipitation, and vegetation percentage in Karaj, Eshtehard, and Taleghan, respectively.

Biodiversity and sustainable development are important goals in environmental protection that in order to have high biodiversity, it is necessary to identify and preserve ecosystems and all species of animals and plants as well as microorganisms in it. Predator bugs (Heteroptera) are efficient predators in most agroecosystems, which have powerful role for control of agricultural pests. These beneficial insects were evaluated under four categories a/ species diversity, b/ percentage of relative abundance and structure of species composition, c/ habitat similarity index, and d/ population fluctuation in sugar beet fields of six provinces (Isfahan, Hamadan, Golestan, Chaharmahal & Bakhtiari, West Azarbaijan and Khuzestan) during 2009-2013. In this research, in total of 24 species under six families, Anthocoridae (eight species, two genera), Geocoridae (three species, single genus), Miridae (three species, single genus), Nabidae (three species, single genus) and Reduviidae (seven species, seven genera) were collected and identified. Additionally, totally 216 specimens of predator bugs were collected from sugar beet fields, which Orius albidipennis, O. laevigatus and O. laticollis with 11.1%, 10.6% and 9.7% of percentage of relative abundance, respectively have the highest abundance among all the species and are dominant species. The highest habitat similarity was obtained between Myandoab (West Azarbaijan province) and Dezful (Khuzestan province) (57.1%). The maximum population density (3.92) was obtained in July.

Woody rangelands are a combination of tree plants in the upper stratum and herbaceous plants in the sub-stratum, both of which are interconnected. Upper stratum coatings have different effects on subterranean plants. The aim of this study was to investigate the effect of tree cover crown on the diversity of subspecies in the Nejdarre reserve. For this purpose, three tree species, Acer monspessulanum, Pistacia atlantica and Crataegus azarollus were selected, which have relative importance in the herbaceous composition of the upper stratum. Using one-square-meter plots, the percentage of vegetation covered under trees and rangeland open space between trees (micro sites) was recorded. Species diversity indices were then calculated for each of them. Data were analyzed by two-way ANOVA and Duncan tests. According to the results, open tree-free micro-sites have higher species diversity compared to tree-lined micro-sites. In addition, the north and south directions of the slopes were not significantly different in terms of species diversity. P. atlantica had allelopathic and depressive effects compared to other species and C. azarollus increased the diversity indices in some cases. The results of regression analysis between species diversity indices under morphological cover and morphological characteristics of trees showed that with increasing trees height and decreasing their shading diametre, the under-species diversity increased significantly. Therefore, in order to increase the diversity of under-species species, tree management should be carried out to increase height of tree. In breeding projects, measures should be taken to increase the species without allopathy in the tree plant community.

Reforestation operations, recovery and acceleration of the regeneration and rehabilitation process of deforested areas are important to reach the pioneering forest. The current research aimed to study the effect of native broad-leaved species, redwood (Sequoi sempervirens) species and natural forest in Sardabrood forest, located in Mazandaran Province. For this purpose, four hectares from each studied forest stands (i.e. natural forest, redwood, maple, maple-alder and alder) were considered. In each of the stands, 16 sample plots (20 m ×20 m area) were taken to study of species diversity, richness and evenness indices in the term of plant biodiversity. Based on our data, the species of Carex sylvatica L. -Oplismenus undulatifolius (Ard.) P. Beauv- Pteris cretica L.- Viola alba L. - Microstegium vimenium (Trin.)- Ruscus hyrcanus Woron.- Rubus persicus Bioss. were found in all of studied stands. The highest diversity of forest floor belonged to the natural forest, so that the highest values of Simpson (0.94) and Shannon-Wiener (3.17), Camargo (0.49) and Smith-Wilson (0.24) were found in the natural forest. The greater amounts of Margalef (7.34) and Menhinic (4.78) were allocated to the redwood plantation. In the present study, monoculture plantation has led to the reduction of biodiversity. It is recommended to managing the degraded ecosystems. While maintaining the long-term quality and sustainability of forested areas, the maintenance of natural stands is prioritized and the reforestation with non-native needle-leaved species should be considered as next priority.

Investigating the vegetation of protected areas and its harmful agents such as Erysipelas fungi is an important issue for evaluating such areas. The aim of the present study was to investigate the biodiversity of Erysipelas fungi and their hosts in the central and peripheral zones of Oshtorankouh Mountain. The analysis could the basis for further studies and provide basic biometric information of plants in terms of infection with pathogens in these areas.

In order to study the biodiversity of these fungi and their host plants, 10 plots in the central zone and the same plot number of peripheral areas in Oshtorankouh Mountain were selected and infected plants and fungal species were identified using their morphological characteristics. Then, the biodiversity indices of Simpson and Shannon, uniformity indices of Eviness, and richness indices of Margalef and Mannheicks were estimated for these species by PAST software. After that, the relative abundance percentages and total abundance of these species were estimated. The correlation between these indices was analyzed using the Leven test.

Eighteen pathogenic fungi species belonging to 6 genera on 40 plant species from 15 genera were identified. The results of the study showed that the highest relative abundance of fungi species belonged to Leveillula the Astreaceae family for plants. There was no significant difference between biodiversity, richness, and uniformity indices of the studied areas. But, there was a difference between the elevation classes in terms of the relative abundance of pathogenic fungi. The correlations between diversity and richness indices of infected plants and between these two indices in pathogenic fungi were also positive and significant (p <0.01).

Most plant species hosts are new records for Iran or even in the world. Damages by such fungi along with other harmful factors and the critical situation of the area occupied by these species threaten the plants of the region.

Generally, oligochaetes as a well-known group of earthworm invertebrates with global distribution have been considered from two Ecological and taxonomical point of view. Species diversity of oligochaetes was investigated in Jajrood River, Caspian Southern basin, Iran. This research began in autumn and winter and specimens were collected from 7 collecting stations using a kick sampling approach across the river. Today, the use of modern methods, including genetic markers, provides a more accurate understanding of the species To evaluate the diversity and facilitate identification of the oligochaete species, both DNA barcoding, using the mitochondrial gene cytochrome c oxidase subunit I (COI), and morphological identification keys were utilized. As a result, five species including Tubifex tubifex, Tubifex sp., Eiseniella tetraedra, Eisenia fetida, and Eisenia sp. belonging to the families Lumbricidae and Naididae were identified. The results showed E. tetraedra to be the most abundant species, which consists of four divergent lineages in this river system.

Identification, species diversity and abundance of Nemacheilidae were carried out in the rivers of Tehran province from autumn 2018 to autumn 2019 for twelve months. For this purpose, 10 sampling stations were selected. The samples were catching by electroshock, then fixed with alcohol and transferred to laboratory for biometry. The results of this study showed that three species belonging to the Nemacheilidae live in Jajrood, Hablehrood and Lar Rivers in Tehran province. Oxynoemacheilus bergiana with 77.27% highest and Paracobitis iranian with 15% and Oxynoemacheilus angorae with 7.73% lowest species diversity at selected stations. Also in Saeedabad station, the frequency of Oxynoemacheilus bergiana was 77.27% and Paracobitis Iranian was 3.18%. At Khojir station, the frequency of Paracobitis iranian was 3.63%. In Zarrin Dasht and Simin Dasht stations, the frequency of Paracobitis iranian is equal to 4.1%. At Lar dam and Delicha stations, the abundance of Oxynoemacheilus angorae was 5.45% and 2.27%, respectively. Also, the highest density of fish caught in the season belonged to summer, autumn, spring and winter, respectively. The frequency of Oxynoemacheilus bergiana was 34.1% in summer, 20% in autumn, 11.8% in winter and 11.336 in spring. Paracobitis iranian was 8.63% in summer and 6.37% in spring. Oxynoemacheilus angorae was 5.45% in summer and 2.28% in autumn.

Species diversity of ants (Hymenoptera: Formicidae) within three subfamilies Dolichoderinae, Formicinae and Myrmicinae was studied in forest ecosystems in northern parts of Iran. The sampled areas of the present research were Jangal-e 2000 and 3000 Tonekabon, Dalkhani forest in Ramsar, Khoshrudpey forest in Galogah, Urim forst in Savadkuh (Mazandaran province), Abr forest in Shahrud (Semnan province), Arasbaran forests (East Azarbaijan province), Golestan National Park (Golestan province), and Guisum forest in Talesh (Guilan province). In total, 27 species within 12 genera and three subfamilies Dolichoderinae (two species, one genus), Formicinae (10 species, five genera) and Myrmicinae (15 species, six genera) were collected and identified. Upon the results of this research, the highest niche similarity index was obtained between Abr forest and Golestan National Park (75%), and then Dalkhani forest and Jangal-e 2000 and 3000 (55.5%). Among the collected species, three species Tapinoma erraticum (Latreille, 1798), Cataglyphis livida (André, 1881) and Monomorium abeillei André, 1881 with 22, 20 and 18 collected specimens, and 6.89%, 6.26% and 5.64% of abundance percentage, respectively are dominant species in forest ecosystems in northern Iran.

The present study was carried out to investigate the diversity and distribution of the Polychaeta species in the Qeshm Island and the effect of desalination plants on their communities. The desalination plants provide a large portion of Qeshm Island drinking water. So, their waste waters could effect on environment especially benthic animals near the coastline. Substrate sampling was carried out in summer and winter 2014 from 9 stations. Station 1 was situated near (desalination site) with the highest temperature and salinity in both summer and winter season, which shows the effects of drainage waste water on environment condition. The substrates of the most stations were silt-clay. At the stations 4 and 5, which sediments included more silt and clay, organic matters were higher than other stations. In this study 49 genera and species were identified. There was a significant negative correlation between the polychaetes abundances and sediment content of silt and clay observed. The higher abundances of polychaetes were found in the stations with lower content of organic matters and greater grain size sediments. The genera Cossura sp. and Scoloplos simplex which related to Cossuridae and Orbiniidae families respectively were dominant specimens. The lowest level of diversity was estimated in station 1. Diversity and dominance indices at stations near the wastewater outlet showed significant differ in both seasons (P<0.05). Finally, it seems that desalination plant may affects adversely on species diversity by increasing of temperature and salinity in short distances.

Accelerated growth of human population as well as technological advancements has put a great pressure on biodiversity. The challenge of reducing biodiversity in the natural ecosystems of the planet is one of the major issues in the near future. In this research, the flora of Valuye, Kiasar were evaluated to select the main protected sites and also the effect of altitude and direction on plant diversity and richness. The sampling was carried out along 14 transects (50 m) with a total of 140 plots in two directions (north and south) and 3 altitudinal intervals (i.e. six ecological sites). Our findings presented 78 plant species from 20 families of which Poaceae family had the most frequency (23%) in the studied area. It was revealed that plant diversity and species richness are significantly affected by altitude and direction. The floristic results showed the highest species richness at 1800-2000m altitudinal interval. The Shannon index displayed the highest diversity at 1800-2000 and 2000-2200 m altitudinal intervals. The results showed that there is a significant difference (p < 0.05) between north and south directions based on Simpson, Gini-Simpson and species richness indices. High plant diversity and the presence of high number of vulnerable species in third site (2000-2200 m altitudinal interval and northern direction) indicated that this site could be as conservation priority. The southern sites at all altitudinal intervals (i.e. 1600-1800, 1800-2000 m and 2000-2200 m) were considered as restoration priority due to the low plant diversity and species richness.

The purpose of this study was to evaluate the impact of the enclosure on the quality of gonbad rangelands using density, diversity and species richness indices.. vegetation sampling was done based on systematic random sampling. Five transects of 1000 meters were considered separately for vegetation characteristics in each region. The species density was calculated by counting the number of bases in the plot, the species diversity was calculated by the Shannon-Wiener diversity index and species richness counting the number of species in each plot. After analyzing, it was determined that the enclosure has a significant effect on species density, species diversity and species richness. Generally, palatability plants and diversity and richness of the species were significantly increased in the protected area. Species diversity in the grazed area increased from 1/798 in the protected area to 2/236. There was a significant decrease in the amount of species richness in the affected area, and from 11.626 species per square meter in the protected area, it reached 9.253 species per square meter. The results indicate that the specimen area has been enclosed with enclosure, vegetation characteristics in the path of sequencing and achieving ideal conditions, but it still needs attention and continued

 Biodiversity indices and abundance of demersal resources in Hormozgan waters (53 00E to 57 00E) was studied by bottom trawl survey during winter season, 2013. Sampling was done by R/V Ferdos 1. In this study, 89 stations within the 10-20 m, 20-30 m and 30-50 m depth layers were sampled and abundance and species diversity of demersal fish communities at different depths were evaluated using various indices. In this study 99 taxa communities were identified including 88 fish species and 13 species or species groups that belonged to the other marine organisms such as crabs, sea cucumbers, sea snakes, jelly fish and corals. The value for the Shannon (H́) index for the entire investigated area (10-50 m depths) were 3.21, Simpson (D), 0.06, Pielou (J), 0.69, Margalef (R), 7.55 and Menhinick (IMen), were 0.16. The value indices in different depths of 10-20 m, 20-30 m and 30-50 m were identical. Based on the results of Shannon and Simpson indices, this area has a fair quality of population in number of species, however species richness indices indicated low species richness and due to high water temperature and salinity degree, this area is under stress.

Nowadays, maintaining and developing of Green spaces in order to improve life quality and sustainability of the cities is very important. By measuring and reviewing the qualitative and quantitative characteristics of trees can be identified more resistance species and used in the future plans. In this study, quantitative characteristics (tree diameter and height) and decay have been examined. The diversity and richness of tree species were calculated on the margins of Chaharbagh Abbasi, Chaharbagh Paein and Abbas Abad streets, using PAST software and Ecological-Methodology, and compared with each other. The results showed that in Charbagh Abbasi Street, Margalof and Munnikh species richeness were 0.604 and 0.182 respectively, Chaharbagh Paein Avenue, respectively, was 0.21 and 0.643 respectively, and Abbas Abad Street, respectively, was 0.624 And 0.202. Also, the Simpson and Shannon-Weiner variations for each of the three streets were equal to 0.445, 0.721, 0.4487, 0.0899, 0.894 and 0.739 respectively. In general, the results indicated that Abbas Abad's biodiversity and bioavailability are relatively more than the two other streets.