Mehri Dinarvand; Mohammad Fayaz; Hashem Keneshlo; Kourosh Behnamfar; Sajad Alimahmodi sarab; farhad khaksarian
Volume 29, Issue 1 , February 2022, , Pages 99-111
Abstract
Measuring the diversity and identifying plant vegetation traits and functional groups and classifying them, in addition to helping to accurately identify the vegetative capacity of the area, helps us to understand the vegetation response of the area to disturbances and presence. Potentially resistant ...
Read More
Measuring the diversity and identifying plant vegetation traits and functional groups and classifying them, in addition to helping to accurately identify the vegetative capacity of the area, helps us to understand the vegetation response of the area to disturbances and presence. Potentially resistant species with similar or invasive traits help. The purpose of this study was to investigate and evaluate the vegetative status of the region, the trend of changes and evaluation of the second sequence of dust centers in Khuzestan after planting seedlings in different ways. Functional groups (PFTs) were used. To evaluate the changes in the vegetation of the area by field survey, 15 transects of 100 meters with distances of 50 meters were systematically randomly selected (the first transect was randomly selected and the rest with a defined distance of 50 meters). Due to the uniformity of plant species composition and the absence of environmental effects, a total of 180 fixed plots with dimensions of 1 square meter (location recording with GPS device) were installed. The results of a recent study in three areas of the dust center in the southeast of Ahvaz showed that in selected areas, various irrigation methods along with rainfall will cause significant changes in the percentage of cover (frequency) and the number of species from 2017 to 2020. Functional groups in the Tovayel region with surface irrigation (Faro) In 2020, nine groups were identified, in Bagan region with tanker irrigation and hole digging with seven excavators, and in Hanitieh region with tanker irrigation and hole digging seven functional groups. The results of T-test analysis also showed that there is a significant difference between the average of the two values of all indicators, including the diversity of Shannon and Simpson in March 2017 and March 2020 for all three regions so diversity indicators raised since number of species and cover increased.
Mehri Dinarvand; Kourosh Behnamfar; Abdolhosein Arami; Sajad Alimahmoudi Sarab; Kahzad Heidari
Volume 28, Issue 3 , October 2021, , Pages 593-604
Abstract
The study of vegetation and the measurement of diversity indices are suitable tools for studying the status of forests and rangelands and evaluating them. The purpose of this study is to evaluate the trend of vegetation changes during four consecutive years and in two seasons in the Bagan region. For ...
Read More
The study of vegetation and the measurement of diversity indices are suitable tools for studying the status of forests and rangelands and evaluating them. The purpose of this study is to evaluate the trend of vegetation changes during four consecutive years and in two seasons in the Bagan region. For this purpose, 5 transects of 100 meters with distances of 50 meters in the study area were considered systematically randomly. A total of 30 plots of one fixed square meter were installed along the transects. In two growing seasons, spring and fall, from 2017 to 2020, the type and percentage of cover of native species were harvested. Dominance, uniformity and diversity of Simpson, Shannon and Hill species were measured using PAST and R software. The results of one-way analysis of variance (ANOVA) showed that there is a significant difference between the mean of dominance, Shannon and Simpson indices, percentage of cover, and the number of species in the spring of different harvest years. In fall, except for the dominance index in other indices during July 2019 compared to 2018, there was a significant difference. From the results, it can be concluded that despite the return of some annual or short-lived species such as Bienertia cycloptera Bunge and Salsola jordanicola Eig. following irrigation of cultivated seedlings and rainfall, the study area is still sensitive and fragile and needs to be managed and confined until proper rehabilitation.
Hamidreza Fallahi; Parviz Rezvani Moghaddam; Mehdi Nassiri Mahallati; Mohammad Ali Behdani
Volume 21, Issue 1 , June 2014, , Pages 62-74
Abstract
In this study, the effects of reconstruction and conservation were investigated on plant diversity of the region of the international Carbon Sequestration Project in Hussein-Abad, South Khorasan province. In the study area, four vegetation types including Haloxylon persicum, Atriplex conescens, Haloxylon ...
Read More
In this study, the effects of reconstruction and conservation were investigated on plant diversity of the region of the international Carbon Sequestration Project in Hussein-Abad, South Khorasan province. In the study area, four vegetation types including Haloxylon persicum, Atriplex conescens, Haloxylon persicum + Atriplex conescens and Zygophyllum eurypterum were planted in 2004. Six years after that, the plant diversity indices of four replanted vegetation types along with control vegetation type (no replanting and conservation programs) was studied in two different dates (April and May) in 2011. For this purpose, 51 quadrates (2 × 2 m) were used in each vegetation type. Results showed that the maximum plant diversity and vegetation coverage were observed in Haloxylon persicum + Atriplex conescens (30 species and 22.5%, respectively) vegetation types, and the minimum values of these indices were recorded in control (20 species and 5.5%, respectively) vegetation type. The highest and the lowest values of plant density were obtained in Atriplex conescens (539,000 plant. ha-1) and control (179000 plant. ha-1) vegetation types, respectively. The Margalef’s richness index was higher in all protected vegetation types, while uniformity index and Shannon diversity index were higher in the control vegetation type. The frequency of 65% of plant species was less than 20% and about 45% of the plant species belonged to therophytes. Overall, the experimental results showed that desert ecosystems could play an important role to improve global biodiversity if proper management programs are employed.