Iranian Journal of Forests and Rangelands Protection Research
Year:2020 | Volume:18 | Issue:1 (35)|Papers Count:8

Reduced rainfall and drought occurrence by restricting the migration of mangroves to the uplands have increased the vulnerability of these ecosystems to sea level rise. Therefore, monitoring the changes in the landward and seaward extent of mangroves can provide valuable information on the response and degree of vulnerability of these ecosystems to sea level rise. The aim of this study was to investigate the trend of changes in the landward and seaward extent of mangroves along the coasts of the Hormozgan province. To this end, the mangroves in the Khamir, Tiab and Jask habitats were mapped using satellite imagery in 1986, 1998 and 2016 and changes in the landward and seaward extent of mangroves were investigated during the periods before and after 1998 (the period of occurrence of long-term droughts on the southern coasts of Iran). The results showed that in the post-1998 period, which corresponds to long periods of drought on the southern coast of Iran, the landward extent of the mangroves was reduced (272. 7 ha reduction in Khamir) or the trend of development of landward extent has decreased dramatically, such that in Tiab and Jask the increase in the landward extent has decreased from 463 and 165 ha to 35 and 13 ha, respectively. In addition to the significant impact of reduced rainfall, human factors such as livestock grazing and fueling (especially for the mangroves located in Khamir), development of aquaculture and pollutants have also played an effective role in the regressing of these habitats.

The aim of this study was to predict and investigate the trend of land use change in Manasht-ghalarang protected area in Ilam province using Landsat satellite imagery (L5 TM-1984, L5TM-1999, L8 OLA-2014). After geometric and atmospheric correction on satellite images, four land uses including agriculture, garden, pasture and forest were identified in the study area. Comparison of maximum likelihood (MLC) and nearest neighbor (KNN) methods was used to classify satellite images, and post-classification comparison methods, the difference of vegetation index (NDVI) and principal component analysis (PCA) differences were used to identify land use changes. Prediction of land use changes in 2024 was performed using the automated fusion cell and Markov chain model. In general, the classification of images used by the MLC method provided a higher probability of accuracy than the nearest neighbor method. According to the classification results, during the period 1984– 2014, a decreases in rangelands and forests and an increase in gardens and agricultural lands were observed. In the comparative method, after classification, most of the changes during the period 1984-1999 were related to the conversion of forests to agriculture, while in period of 1999-2014 were related to the conversion of forests to pasture. Forecasts of changes for 2024 showed that agricultural land-uses increased by 1. 10%, garden by 0. 52% and rangelands and forests decreased by 0. 76% and 0. 86 %, respectively. Based on the results, the use of Landsat images in combination with the Markov model in modeling land use change, had high accuracy and can be effective in decision-making and management of the region.

Knowledge and awareness of the climate of each region is the basis of infrastructure planning in all issues related to that region. Understanding the type of climate and its changes can be effective in maintaining the stability of the National Botanical Garden of Iran as one of the most important tourist attractions in the country. The aim of this study was to determine the climate type of the National Botanical Garden of Iran in order to have an overview for the use of researchers in different departments of the Forest and Rangeland Research Institute and also to understand the change in the type of garden climate in a complete climatic period (30 years) for the use of those involved in planning, support and protection of the National Botanical Garden of Iran. In this study, in order to determine the type of garden climate and its changes over three decades, an innovative model for detecting climate change has been used. To this end, the monthly temperature and precipitation data of Chitgar station and to complete it, the global data network of the Climate Research Unit of the University of East Anglia, version 3. 32 was used. The results showed that at the annual scale, the type of garden climate changed from semi-arid to arid. On a seasonal scale, winter has undergone the most changes, with the type of climate changing from semi-humid to Mediterranean. On a monthly basis, the most changes were in March and then in February. Given the importance and diversity of species in the garden, as a national capital, the continuation of these changes may threaten the extinction of many plant communities in the future. Climate change due to global warming in the coming decades in Iran is inevitable and the National Garden will not be excluded from the effects of these changes, so appropriate programs for climate change adaptation should be considered to support and protect it.

In this study, with respect to the importance of fires in Zagros vegetation zone, temporal and spatial data of fire incidence, from 2002 to 2018, in natural areas of Kermanshah province was extracted using MODIS active fire data. Then the frequency of fire incidence was analyzed according to the physiography of the study area in different classes of slope, geographical direction and altitude. According to the results, the highest and the lowest frequency of fire incidence in forests were observed in slopes classes of 15-30% and >80%, respectively. In rangelands, the highest and lowest frequency of incidents were observed in slopes classes of 0-15% and >80%, respectively. In the forest area, the highest frequency of fire incidence was observed in the altitudes of 1000– 1500 m and 1500-2000 m and the lowest frequency was observed in the altitudes of 115– 500 m and >2500 m. In the rangelands, the highest frequency of fire incidence was observed in the altitudes of 1000– 1500 m and 1500-2000 m and the lowest frequency was observed in the altitude of over 2500 m. It was also observed that the frequency of fire incidence in the northern and southern aspect directions was remarkably higher than the eastern and western directions. The results of this study emphasize that in addition to the type of physiography of the region, the frequency of fire incidents is significantly dependent on the surface area of each form of physiography, which can be very important in fire management planning.

During conduction a survey of collection and identification of weevils, in the years 1993-2013, totally 32 species belonging to 22 genera were identified. Among them, five species including Dorytomus ictor (Herbst, 1795), D. melanophthalmus (Paykull, 1792), Mogulones mendax (Schultze, 1898), Paramecops sinaitus (Pic, 1930) and Polydrusus mollis (Stroem, 1768) are new records for Iran. The specimens were deposited in the Insect Museum of Research Institute of Forests and Rangelands, Tehran, Iran.

In a large area of the Iran rangelands, there is air dryness and deficiency of moisture, which can be increased by using some mechanical operations in certain parts of the rangeland. In this study the effect of storing operation of curved pit and its dimensions on the restoration of vegetation and soil of pastures was studied in Reihan plain of Ravar-Kerman province. For this purpose, random sampling was performed in small, medium and large curved pits and a region between two pits. In each plot the list of available species, canopy cover percentage, production and the number of plant rootstocks were measured. Ten soil profiles were made and sampling was done from the first 30 cm of soil surface in each area. The data was analyzed using one-way ANOVA and Duncan test by SPSS21 software. The results suggested that density, production and vegetation percentage were significantly different in the four study sites (p<0. 05). The largest canpy cover and production was in the large curved pit. According to the uniformity index, the Simpson and Wilson homogeneity index had a significant difference. Based on the Simpson index and the Wilson index, the highest evenness was in small curved pit. Soil analyzing results showed that the organic matter and organic carbon of the large curved pit soil had a significant increase. In general, due to the high sensitivity of rangeland ecosystems in arid and semi-arid regions we can increase the vegetation cover, by curved pit in large dimensions.

Forest management has an essential impact on the growth of medicinal, edible, and poisonous wood-inhabiting fungi. Identification and cultivation of some edible fungi play an important role in supplying food needs and knowing medicinal fungi can be important for maintaining health and treating many diseases. The purpose of this study was to identify of wood-inhabiting fungi on deadwood of Fagus orientalis trees in the Darabkola forests. Also, we categorized these fungi into medical, edible, and poisonous groups, and investigated the amount of deadwood in these forests. After conducting preliminary field survey, sampling was done from deadwood. Identification of fungi in the fungal laboratory through morphology and extraction of ITS nrDNA region was done and sequenced using ITS1 and ITS4 primers, corrected with BioEdit software and analyzed using the data available in NCBI. The results showed that 40 fungi species were identified, among which, 70% had medicinal and economic values, 22% had edible value, and 8% had toxicity characteristic. The results also showed that Trametes versicolor with 10%, Daldinia concentrica and Trichaptum biforme with 7%, Pleurotus ostreatus, Ganoderma lucidum and Fomes fomentarius with 6% had the highest frequency on deadwoods, respectively. Among them, the families related to Polyporaceae with 38%, Xylariaceae with 15% and Ganodermataceae with 10% had the highest frequency, respectively, and the volume of deadwoods in the Darbkola forests of Mazandaran was 5. 31 cubic meters per hectare. In conclusion, in order to manage the deadwood in a forest ecosystem for increasing the diversity of medical and edible fungi, it is suggested to preserve the deadwoods in the forest.

Diatoms are the most diverse group of single-celled algae that contain fucoxanthin, clorophyll a and c. This group is considered as algae, the first group of food chain in aquatic ecosystems, however, a species of them with the scientific name Didymosphenia geminata (Lyngbye) M. Schmidt as an invasive species in North America, Europe, New Zealand and Australia are known to cause many environmental problems. During investigation on diatom flora of the Karaj River, Didymosphenia geminata was found as a dominant species with a relative abundance of 10% in January 2011. The dominance of this species in the Karaj River is a threat for the ecosystem of the river. Therefore, to protect the river ecosystem, monitoring programs should be conducted annually and in case of high prevalence of the species, measures should be taken to clear the species from the river.