Myosotis diminuta Grau (Boraginaceae) is recorded for the first time for the flora of Iran. It was rediscovered in 2013 in Zanjan Province, NW of Iran, in a wetland habitat far from its previously known habitat after not being documented for more than 100 years. A detailed taxonomic description and photographs are provided to facilitate its identification in the field. Also diagnostic characters to define Myosotis diminuta from its close relatives are provided.

trees provide a wide range of benefits to humans and other living organisms. An accurate method tree species identification will improve their management and conservation. Also, tree identification and description are crucial for genetic study, biodiversity conservation, management and regeneration strategies. The conventional methods of tree identification are time-consuming and requires a high level of expertise, necessitating development of a more efficient tree identification means. In this research, a QR code system for tree identification was developed. tree data were collected from campuses of two tertiary institutions in Akure, Nigeria: Federal University of Technology and Federal College of Agriculture. System design was built around a three-tier architectural model. PostgresSQL was used as the Database System, the lowest tier. The Middle tier is the Web Server, Apache HTTP Server. Php 8. 1 was the scripting language that communicates with the database. For the Client tier, HTML, CSS and Javascript were used. The QR code generator was developed using PHP 8. 1. The PHP script used a QR code library to generate the QR code image. The QR code is linked to the website database containing all tree species information. The generated QR codes were attached to trees, and when scanned, the website is automatically launched and the tree information is retrieved. A survey was conducted to get end-users’ feedback within the study sites. The results obtained revealed that the QR codes are easy to use, and can make tree identification more interesting, thus increasing people’s knowledge about trees and improving trees management.

One of the most important ideas in forest management is maintaining and developing of biodiversity. Biodiversity measuring is one of the most difficult works, time consuming, high cost and in this context; there is not exist comprehensive and standard recipe toward biodiversity measuring. This study has been accomplished in order to preserve of biodiversity in Darabkola forests (area 280 ha) with measuring tree species diversity in two geographic aspects (northern and southern). In order to investigate of tree, eighteen plots (1000 m2), were taken by a systematic random sampling method. Values of species diversity was calculated using Simpson, Shanno - wiener and species richness Margalef, Menhenich and evenness (Pit and Hill) indices at each plot. species diversity, species richness and evenness indices Value maximum, at north and southern aspects is related to Shanon-Viner, Margalef and Hill indices, respectively. Results indicated that species diversity indices at northern aspect is more than southern aspect, but richness species indices was the same in the both aspects. For northern and southern aspects Pit and Hill indices were higher respectively. Also results indicated that species diversity indices and evenness have significant correlation with together, but there wasn’t a significant correlation within species diversity indices and evenness. As a result, evenness indices have higher effect to increase biodiversity in comparison with richness.

One of the most important goals of the ecological management of forests is to enhance the complexity of the structure of the forest stands. Also, despite the recommendation to increase mixing, the consequence of the presence of Rare tree species on the forest ecosystem functions has not been well clarified. This research was conducted to analyze the presence and abundance of Rare tree species on the structural complexity index in beech stands. the number of 12 one-hectare study areas with the presence of Rare tree species was selected and after measuring the structural features, the multivariate complexity index was determined in each of the plots. We employed ten variables including stem per hectare, mean diameter at breast height, coefficient of variation of dbh, diameter Gini coefficient, number of trees with a diameter larger than 100 cm at breast height, the ratio of the number of trees in different stories, the faction of canopy gaps, amount and volume of dead woods and tree size variation to the calculation of this index. Comparing the correlation between the relative importance value of beech, Maple, and other Rare tree species with the structural complexity index revealed the differences in complexity variation toward the rising in the abundance of tree species. Accordingly, beech and hornbeam, as the two dominant tree species with the highest relative value, are weakly correlated with this index. While the maple and other Rare tree species including alder, elm, and lime positively correlated with increasing complexity in the structure. According to the positive effect of the presence of Rare tree species on the complexity of the structure of forest stands, it is recommended to the retention of Rare tree species in stands to increase the complexity of the forest stands structure.

tree planting with drought tolerant species, particularly Acacia and Eucalyptus species may be considered as a logical method for rehabilitation of marginal lands which can potentially meet the needs of local people in terms of wood, fuel wood, fodder, edible fruits, etc. These goals may be much better attained when the trees are planted in floodwater spreading (FWS) systems which drastically change the desert ecosystems through provision of more water and better rooting environments. In 1994, a pilot project was carried out in FWS systems in Gareh Baygan Plain in Fars Province of Iran to study the growth and performance of four Eucalyptus and four Acacia species which had previously been tested successfully in a preliminary adaptation experiment. A randomized complete block design with four replications was employed to establish the experiment. Each replication comprised of eight plots (species) and each plot contained 49 trees with 3m×3m spacing. The seedlings were irrigated only by rain and ephemeral floodwaters. In a ten year period, growth parameters including survival percentage, height and diameter at breast height were assessed or measured every year. The existence of pests or diseases and the viability of the trees were also monitored annually and the final evaluation was made at the age of ten. Survival and growth performance of the trees were quite satisfactory. Eucalyptus camaldulensis, E. oleosa, Acacia victoriae, A. salicina, and E. microtheca were all promising species, showing over eighty percent survival in the final year of experiment and were not significantly different from each other. The survival of E. fruticetorum was significantly different (p=0.0001) from those of the other species. Eucalyptus camaldulensis showed the highest growth in terms of height and diameter, while A. saligna ranked the lowest. It may be concluded that E. camaldulensis, E. oleosa, E. microtheca, E. fruticetorum, A. salicina, and A. victoriae were highly promising species and may be recommended for large-scale plantations in arid zones of southern Iran, using floodwater spreading systems. Moreover, further tests of cold resistant provenances of A. cyanophylla and A. saligna are recommended.

Background and objectives: The roots of the plants are used as a kind of materials in the slopes preservation and resistance. Because in addition to helping to preserving and resisting the environment, it has recovery ability and has no harmful and negative effects on the environment and has no additional costs too. Plant cover is caused for pastiness between soil particles for having root system and has significant impact in slope stabilization, for this reason, the biological characteristics of different species has great importance. The quantity of reinforcement depends on root biotechnical characteristics such as root density and tensile strength. In this study assessed these biotechnical properties. Materials and methods: In this study, two non-native afforested stands of pine (Pinus Sylvesteres) and acacia (Robinia Peseudo acasia) and two natural stands with native species of hornbeam (Carpinus Betulus) and summer alder (Alnus Subcordata) with similar habitat conditions (altitude, Slope and direction of slope, soil type, geology, etc) in the forest of Neka city (Neka-Zalmarud forestry plan) was and Six trees of each species were randomly selected for later analysis. The Root Area Ratio and tensile strength were investigated. Profile trenching method was used to analyze and compare their root distribution. The walls of the profile are divided into 10 cm horizons. Number and diameter of protruded roots in each depth were measured. Finally, the percentage of Root Area Ratio in each horizon was calculated. Standard Santam was used to determine the tensile strength of roots. Root samples were collected at the bottom (30% slope) of trees. Results: The results indicated that the Root Area Ratio were decreased with increasing depth According to the exponential function. The Root area ratio in non-native species is higher than native species. Which has obtained for Carpinus Betulus, Alnus Subcordata, Robinia Peseudo acasia and Pinus Sylvesteres, 0. 033± 0. 002, 0. 081± 0. 002, 0. 026± 0. 018± 0. 177± 0. 015 percent respectively. The diameter range of the tested roots was 2-9 mm. The results of tensile strength tests showed that with increasing diameter, the amount of tensile strength according to the According to the exponential function decreased. There is a positive power relationship between root diameter and tensile force. Conclusion: In this research tensile strength of native species is more than non-native one that has obtained for Carpinus Betulus, Alnus Subcordata, Robinia Peseudo acasia and Pinus Sylvesteres, 31. 93± 10. 3, 17. 57± 6. 98, 18. 4± 2. 41, 9. 77± 5. 46 Mpa respectively. The results of this work may help us when applying an efficient bioengineering technique