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Background and objectives: In recent decades, the Khamir and Qeshm mangrove forests in southern Iran have suffered significant destruction due to various human activities, including the construction of docks, commercial and tourism ports, deforestation, and unplanned tourism development. These forests, which provide valuable ecosystem services, have faced indiscriminate and unplanned development, as well as insufficient attention from local communities. Therefore, understanding the spatial distribution of plant species in this area is crucial for effective planning and enhancing the protection of these valuable biological resources. This study aims to identify suitable areas and model the presence of the mangrove tree species Avicennia marina (Forssk.) Vierh. in the Khamir and Qeshm mangrove forests to facilitate the restoration and proper distribution of this species. Methodology: The habitat suitability map for A. marina was prepared using MaxEnt modeling. A total of 234 points were randomly recorded using the Global Positioning System (GPS). To investigate the spatial distribution of A. marina, various environmental factors affecting its geographical distribution were analyzed using ArcGIS 10.8 software to generate maps and environmental variables. The environmental variables were selected based on theoretical foundations, previous studies, and expert opinions. The model included 18 climatic variables and 5 physical variables affecting the distribution of A. marina. The physical variables included maximum wave height, beach slope, tidal fluctuations, water salinity, and beach material (sandy- gravel, muddy, back beach (sand material)). All layers were prepared in ASCII format with a cell size of 1 km, and MaxEnt 3.4.4 software was used for modeling. Results: The area under the curve (AUC) obtained from the MaxEnt algorithm indicated excellent predictive power for the presence of A. marina in the study area, demonstrating the model’s ability to distinguish between suitable and unsuitable areas. The overlap of training and test data also confirmed the model’s accuracy. The contribution analysis of each environmental variable in the model showed that maximum wave height, annual average temperature, tidal fluctuations, and water salinity were the most influential variables. Specifically, maximum wave height and annual average temperature had the largest influence on the distribution of A. marina, while the minimum temperature of the coldest month had the least effect. The response curves indicated that maximum wave height (1 to 2 m) and average annual temperature (26.8°C) were the most important independent variables, with an inverse relationship to the probability of A. marina presence. As wave height and average annual temperature increased, the probability of species presence decreased. The suitability map for A. marina in the Khamir and Qeshm mangrove forests showed that the highest suitability was in areas with minimal wave height and less exposure to tidal fluctuations. Favorable areas for the presence and development of A. marina included the northern areas of Khorkhoran Islands, Mardove Island, and the northeast of the Khamir-Lashtghan habitat. In general, the species was more dispersed in areas with low wave height and minimal water level fluctuations. Conclusion: The study provides key information on the impact of environmental variables on the distribution of A. marina, offering an important strategy for protecting the biodiversity and valuable resources of the species in the Khamir and Qeshm mangrove forests. The suitability map serves as essential information for planting and reviving these natural habitats. [ABSTRACT FROM AUTHOR]

This research was conducted with the aim of determining the biodiversity of Pertaran communities in three areas with mangrove cover and in 9 stations including one station in Gowatr Bay and 4 stations in each of Gowatr bay and Bahu Kalat on the eastern coast of Chabahar port. From each station, from the winter of 2019 to the fall of 2014, three sediment samples were collected seasonally for the separation and identification of sediments and one sample for the analysis of grain size and total organic matter of the sediments by Grab van Veen with a cross-sectional area of 0.028 square meters. In total, 12 genera belonging to 10 families were identified. Among the groups of the detected families of spionidae, the highest percentage of the average frequency with 13.70% was related to the Spionidae family. The survey of the density of the birds in total is 17800 ± 180 in the mentioned seasons, the average density of the birds in winter is 8720 ± 42 and the average density of the birds in the autumn is 9080 ± 181.63 in the mentioned seasons, the lowest average in winter is related to the Nereidae family: 0.5 600±67 and the most number was for Spionidae family: 1280±31.47 individuals in one square meter. The lowest average in autumn was related to the Nereidae family: 560 ± 32.65 and the highest to the Spionidae family: 1160 ± 62.94 individuals per square meter. The results of the parametric one-way analysis of variance test showed that the abundance of Pertaran communities in different seasons and stations had a significant difference (P<0.05) and the average abundance was higher in winter than in autumn. A positive and significant correlation was obtained between the parameters of total organic matter and sediment granularity with density. The low diversity and the low percentage of organic matter in the winter season show the negative effect of the winter monsoon on the biodiversity patterns of the wetlands of the Goater Bay and the decrease in turbulence and stress caused by waves and temperature along with the abundance of organic matter causes an increase in the diversity and predominance of species in It is autumn season. [ABSTRACT FROM AUTHOR]

Deltas of Rud-e-Shur, Rud-e-Shirin and Rud-e-Minab, consisting of mangroves and coastal mudflats, is one of the most important bird habitats on the shores of the Persian Gulf and are protected as an international wetland. In this study, a list of weland birds was prepared based on the data of the results of the semi-winter census of waterbirds, expert reports and field studies. Also, the trend of changes in the waterbird population in the period of 1988-2021 was calculated using the TRIM statistical package with the possibility of application in R ver3.6.3 software called RTRIM. The results showed that, a total of 156 species of 97 genera, 45 families and 18 orders including 98 species of waterbirds, 21 species of prey and 37 species of terrestrial species were identified. The population of waterbirds has a strong increase with a slope of 7.7% per year. In the last ten years, a moderate decline in population has been recorded with a slope of -4.1% per year. The average population of waterbirds in the wetland was 15,479 ± 2,669 and the average number of species was 41.6 ± 3.39. The largest population was in 2019 with 54,356 individuals and the highest number of species was in 2005 with 64 species. Although annual population fluctuations and diversity depended on census-related factors such as program support, bird-watching tools, number of sites, census coverage levels, and the experience of bird counters, the impact of habitat threats such as overfishing aquaculture and the increase in environmental pollution have also increased in recent years. A program to increase stakeholder awareness and strengthen participatory conservation can be effective in reducing wetland threats.

Continual access to precise information about the land use/land cover (LULC) changes of the Earth’s surface is extremely important for any sustainable development program in which LULC serves as one of the major input criteria. In this study, a supervised classification was applied to three Landsat images collected in 1986, 1998and 2018, providing mangrove forests change data in the coastal area of the Bushehr province. The supervised classification results were further improved by employing image enhancement and visual interpretation. Visual interpretation was not only useful in increasing the classification accuracy of the Landsat images, but also in identifying the mangrove forest cover. Post-classification comparisons of the classified images of the mangrove forest area of the Assaluyeh habitat zone during a period from 1986 to 2018 indicated that the area of these lands had been increased by 68.94 hectares, with a percentage change of 43.85%, which was an increase of 1.41% per year. These changes in the Deir habitat zone showed that the area of the land covered by the mangrove forest was 5.25 hectares, with a percentage change of 0.87. In the Mela Ganza habitat zone, the area of the land covered by the mangrove forest was 26.82 hectares, with a percentage change of 6.33, which was an increase in the annual rate of 0.20.

Organisms in different environmental conditions express different genes, which result in different protein expressions. These changes result from the adaptation of the organism to environmental conditions such as the presence of toxic substances. This study aimed to investigate the changes in protein expression in Celeribacter persicus SBU1 isolated from Nayband Bay mangrove forests, cultured in the medium containing phenanthrene as the sole source of carbon and energy. For this purpose, C. persicus SBU1 was cultured on mineral salt medium containing phenanthrene and sodium acetate as treatment and control, respectively. After the extraction of total protein, changes in protein expression were evaluated by SDS-PAGE. Proteins were identified by MALDI-TOF-TOF MS. After evaluating changes in protein content, two bands which showed greater variation in comparison with the control treatment (increased protein expression) were detected. The identified proteins included one ligand-gated channel protein and one unknown protein. In general, the results of this study showed significant changes in the protein content of C. persicus SBU1 after using phenanthrene. The up-regulation of ligand-gated channel protein signified the role of this protein in phenanthrene molecules transport in and out of the cells.

Continual access to precise information about the land use/land cover (LULC) changes of the Earth's surface is extremely important for any sustainable development program in which LULC serves as one of the major input criteria. In this study, a supervised classification was applied to three Landsat images collected in 1986, 1998and 2018, providing mangrove forests change data in the coastal area of the Bushehr province. The supervised classification results were further improved by employing image enhancement and visual interpretation. Visual interpretation was not only useful in increasing the classification accuracy of the Landsat images, but also in identifying the mangrove forest cover. Post-classification comparisons of the classified images of the mangrove forest area of the Assaluyeh habitat zone during a period from 1986 to 2018 indicated that the area of these lands had been increased by 68.94 hectares, with a percentage change of 43.85%, which was an increase of 1.41% per year. These changes in the Deir habitat zone showed that the area of the land covered by the mangrove forest was 5.25 hectares, with a percentage change of 0.87. In the Mela Ganza habitat zone, the area of the land covered by the mangrove forest was 26.82 hectares, with a percentage change of 6.33, which was an increase in the annual rate of 0.20. [ABSTRACT FROM AUTHOR]

Mangrove forests are coastal ecosystems that found worldwide in tropical and subtropical zones. Oil spill causes damage to these marine ecosystems. The objective of this study is study the oil-degrading bacteria in some mangrove forests that located at Persian Gulf. In this study sediments and plant materials were collected from mangrove forests at Persian Gulf (Minab and Khamir ports). Oil-degrading bacteria were screened in specific media. Isolated bacteria were identified by biochemical and molecular tests. Nine crude-oil degrading bacteria were isolated after enrichment at ONR7a medium with 1% crude oil three strains BP14, NP16 and NP19 were selected for further study. These isolated strains were identified as Vibrio azureus and Pseudomonas salomonii. The half percentage of oil was removed by these strains in 15 days of incubation. The highest percentage of crude oil related to NP19 strain with 76 percent degradation. By growth and multiply of these bacteria in field scale we can remediate oil polluted mangrove forest ecosystems.

Mangrove tide etangs which are placed at border line between the arid and sea-land, have a considerable ecological and social–economical value. This study uses (LARS-WG) along with two GCM models (MIRH and HadCM3) and the A1B scenarios to simulate climatic variables of minimum and maximum temperature and rainfall in the past and future periods. In reviewing the uncertainties, the results indicate the high capability of LARS-WG model in simulation of climatic variables simulation specially in arid ecosystems. Based on MIHR downscaling results, minimum and maximum temperatures will increase in cold season from November to March up to ~+4.21°C and +4.7°C respectively. While increasing up to ~+3.62°C and +3.55°C in the warm season from June to October as well. Based on HadCM3 results, minimum and maximum temperatures will increase in cold season up to +3.03°C and +3.3°C in warm season at the end of this century(2100) . Maximum temperature will increase above 38°C during the warm season within the years 2080-2099. It is predicted that the difference between day and night temperature will reach to the minimum level. In this manner, this condition will affect ecological and biological Mangrove processes. The linear regression of observed T-min data shows a +3.14 °C increase over the past 42 years. Based on HadCM3 and MIRH model results, precipitation will increase in warm months and decrease in cold months within the years 2080-2099.

Due to the increasing industrial activities in many tropical and subtropical coastal areas, social concerns in relation to the impact of anthropogenic activities on mangrove forests have been increased. Surface mangrove sediments (0–10 cm) from three mangrove forests in Bushehr, northern Persian Gulf were sampled for metal analysis in April 2009. The concentrations ranged (in µg g-1 dry weight)as fallows: 1795-30240 Al, 6425-51530 Fe, 0.6-3.45 Cd, 14.1-98.28 Cu, 14.1-204.54 Ni, 34.15-191.6 Pb, 57.38-825.26 V, and 44.91–306.15 Zn. The overall average concentrations of above metals exceed the primary standard criteria but meet the secondary standard criteria of the Chinese National Standard of Marine Sediment Quality and United State Environmental Protection Agency (USEPA) Standard. Among them, three mangrove sites in Bushehr, Bidekhun and Basatin were contaminated with heavy metals. Bidekhun is nearest mangrove to the South Pars gas complex, and Basatin is located in neighborhood. In addition, the disturbing of current water in Basatin creek with bridge construction has caused the increase of metal concentrations within this site.

To investigate the vegetative parameters of mangrove communities, sampling was performed in random- systematic method using 8 transects and 37 plots (100m2) in Govater Bay at the southeast part of Iran in Sistan and Baluchestan province (Govater and Bahu creek). The area of mangrove in this location is 672 ha and consists pure communities of Avicennia marina (Harra). On the basis of performed measurements, mean density of mangrove trees was measured 1623 trees per hectar. Mean of height trees and canopy height trees were obtained 264.90 cm and 180.58 cm respectively. Crown mean diameter of trees measured 263.34 cm and the mean of crown density was 54.60 percent. Nature of data (parametric or nonparametric) surveied by tests relating to normality of data and equality of variances and then each variable was analysed according to its nature. Analysis of statistical information performed by spss 13 softwar in format of descriptive statistic of vegetative parameters and investigation of statistical differences and correlations between these parameters. Results showed that, although the Avicennia marina is the only tree species existing in this area, these forests have significant differences regarding to many parameters in two creeks, different transects and along sea to land, that altogether indicate heterogenity of grey mangrove pure stands on basis of these parameters.

Sirik site is an unique mangrove site in Iranwhere Rhizophora mucronata occur with Avicennia marina (Grey mangrove) stands. The structure of mangrove communities as well as their special environmental characteristics differ in the country. Little is known about structure, dispersion and extent of these two mangrove stands by. In order to study the dominant species composition and distribution, IRS satellite image, acquired in 2004, and field sampling were used. The study of mangrove forests showed there exist three types of forest stands in this region; one as pure Rhizophora besides the main estuary and in contact with water, one as pure Avicennia at the end of site toward land and sometimes at the bank of estuary and mixed Avicennia and Rhizophora between two above-mentioned stands. The results showed that the establishment of Rhizophora stands increases from east to west and toward main estuary. The area of mentioned stands using GPS and georeferenced image were recorded 272.6, 43.9 and 326.7 ha for pure Avicennia, pure Rhizophora and mixed stands, respectively. The total area of Sirik forests measures 643.2 ha