جستجوی مقالات مرتبط با کلیدواژه « شکل زیستی » در نشریات گروه « اکولوژی »

Native and endemic plants are considered valuable genetic reserves of each region and are of special importance due to having favorable morphological traits, resistance to pests and diseases, and adaptability to ecological conditions. This research was carried out with the aim of providing a floristic list and identifying the biological and soil characteristics of medicinal plants in Langerud city. Soil samples were also taken from the surface horizon of habitats and their characteristics including soil texture, soil reaction, electrical conductivity and organic carbon percentage were measured. 78 species of medicinal plants belonging to 42 families and 72 plant genera were identified. Of these, Asteraceae is the largest family with 10 species. Also, Rosaceae, Fabaceae, Lamiaceae, Apiaceae and Poaceae families are the next large families with eight, five, five, four and three species, respectively. Aspleniaceae, Brassicaceae, Malvaceae, Hypericaceae, Lythraceae, Onagraceae and Urticaceae consist of two species.  Other identified families include one species. The highest percentage of life form and chorological type of the identified medicinal plant species in the region are Hemicryptophyte (He) and Polyregional (PL) elements, respectively. Also, assessment of the characteristics of the habitats of these plants in the height range of -15 to 325 m.a.s.l. showed the uniformity of the soil texture in the medium to light class, electrical conductivity less than 1 dS/m, soil reaction acidic and good organic matter content. The habitat of many of these species is in the hilly and mountainous areas, in addition to lowlands and plains and around paddy fields.

Prunus eburnea (Spach) Aitch. & Hemsl. is an endemic plant species of Iran-Afghanestan, which has medicinal and nutritional value and distributed in extensive parts of arid and semi-arid ecosystems of Iran. The aims of this study were to investigate the life forms and chorology of associated perennial plant species and biodiversity indices in 52 habitats. Habitats were divided into ten main regions based on main climate, latitude, longitude, phytogeography, altitude, vicinity to other habitats and physiognomy. Some biodiversity indices such as species richness, uniformity, heterogeneity and dominance for each region were measured using PAST software. The results showed that the life form of phanerophyt (48%) and chamaephyt (40%) had the highest percentage of life forms of associated plant species with gray almond in the studied habitats. Perennial plants belonging to the phytogeography of Irano-Touranian region (64%) and Euro-Siberian (13%) had the highest abundance in the habitats of this species, respectively. In a general conclusion, the habitats of this species in the west of the country due to more rainfall and humidity have the greatest species diversity and the number of plant species bases than the central and eastern habitats of the country. In the habitats that are located near the Zagros region of the country, the diversity indices show greater values than the habitats that are located in the Iran-Turanian regions.

The present study was conducted in order to investigate floristic study and to determine life forms and geographical distribution of vegetation in Farsian region of Galikesh county in Golestan province. Sampling was done during growing seasons of 2017 and 2018. In total, 122 plant species belonging to 101 genera and 41 families were identified. Asteraceae (16 species), Fabaceae (13 sp.), Lamiaceae (12 sp.), Boraginaceae (8 sp.) and Poaceae (7 sp.) were the largest families. The largest genera were Convolvulus, Euphorbia and Trifolium each with 3 species. Most of the identified species belonged to the dicots. According to Runkier chr('39')s classification, therophytes (38%) and hemicryptophytes (30%) were the dominant life forms in the region, which indicates destruction and harsh highland condition in the region, respectively. With regard to geographic distribution, the region was mainly affected by Irano-Touranian and Euro-siberian elements.This is reasonable due to the location of the region. Conservational status was available for 9 species, among which 3 sp. were included in group with low risk and 6 sp. in group with data deficient.

To achieve sustainable development as well as the conservation of natural ecosystems and their biodiversity, it is necessary to study ecological foctors and their impacts on plant species diversity. The Khorramabad-Andimeshk highway was selected in the current study to investigate the diversity of the family Brassicaceae. The length of this highway is 100 km and its height ranged from 420 to 1740 m. The altitudinal range was divided into three classes. Sampling was performed separately at each of these classes in six time periods of one month interval. In each month, 300 plots (4 m2) were conducted with a distance interval of 5 km, based on the minimal area method. Data of each class were analyzed, using one-way analysis of variance (ANOVA) to determine the indices of species richness and diversity. A total of 46 species, belonging to 33 genera were identified. The majority of Brassicaceae species, across the study area, were annual plant species (41 species), showing the characteristic of arid and semi-arid environments. Results showed that elevation has no effect on species diversity but it has a significant effect on species richness. In addition, growth time has significant effects on species diversity and richness. The highest level of species richness was observed in the lower altitudes and the highest indices of species diversity and richness were recorded in March and May.

Identification of vegetation and study of geographical distribution of plants in each region is the basis of ecological studies and researches in that area. The purpose of this study was to introduce the flora, life form and geographical distribution of plants in the desert area in the southern of Damghan desert. At first, plant species of this region were collected and identified using available scientific resources. Then scientific name, family name, vegetative form, life form and chorotype of each species were determined using available sources. A total of 53 plant species belonged to 18 plant families were identified in the southern margins of Damghan desert. Amaranthaceae was the largest plant family with 17 plant species and consisted of 32.08% followed by Asteraceae and Fabaceae with 15.09% and 7.55% respectively. The results showed that according to the rankings based on Raunkiaer classification system, therophyte plants with 16 plant species 30.19% were the dominant life form in the study area, followed by chamaephyte plants 28.30% and hemicryptophytes 24.53%. The results of geographical distribution of plants showed that the Irano-Turanian elements with 36 species 67.92% was the largest proportion of the chorological elements in this area, indicating the existence of arid and semi-arid climates in this area.