Flora, life forms and chorology of plant species in the Deh-Kohneh Forest in Sepidan, Fars Province, Iran

[Research]

Flora, life forms and chorology of plant species in the Deh-Kohneh Forest in Sepidan, Fars Province, Iran

M.R. Negahdarsaber¹*, K. Taheri Abkenar¹, H. Pourbabaei¹, Kh. Sagheb-Talebi²

1- Department of Forestry, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran.

2- Department of Forestry, Research Institute of forests and Rangelands of Iran, Tehran, Iran.

* Corresponding author’s E-mail: Sabersiamak@gmail.com

(Received: May. 04. 2016 Accepted: Oct. 19. 2016)

INTRODUCTION

Vegetation of an area, in fact, is the advantage of interactions between biological communities and environmental conditions and also, is in direct relation with evolution of plants species and geographical conditions during the past ages (Ghanbarian et al. 2011). Identification of plants in both applied and scientific aspects have a great role in attention to the importance of vegetation in environmental science, so that we can well understand, utilize and protect the environment. Thus, scientific classification of plants were employed (Vaseghi et al. 2007). Furthermore, with respect to the environmental turbulences like global warming and climate changes which change the number of plant species, we could realize the importance floristic studies in all regions. Also, study on chorology and life - forms of vegetation help us to protect and manage all genetic resources. Raunkiaer’s life-forms system was used to characterize the flora of the area. Plant species and individuals can be grouped into different life-forms classes based on structural and functional similarities (Muller-Dombois & Ellenberg 1974). Life-forms have close relationships with environmental factors and can be viewed as strategies for obtaining resources (Crosswhite & Crosswhite 1984; Cody 1986). Raunchier (1934) proposed a life- form classification system based on the manner in which plants protect their perennating buds during unfavorable seasons. According to this classification system, plant species can be grouped into five main classes: phanerophytes, chamaephytes, hemicryptophytes, cryptophytes and therophytes. This sequence corresponds to an increasing protection of the perennating buds. Climatic types can be characterized by the prevailing life form in plant communities growing under a given climatic regime, using the proportions of species in each life- form class, or the biological spectrum (Raunkiaer1934; Cain 1950; Muller-Dombois &Ellenberg 1974). Few studies have been devoted to the structure and flora of the herbaceous layer in plant communities of Fars Province (Ghahraman1996; Ghanbarian et al. 2011; Taiebikhorami et al. 2007; Khalili et al. 2007; Khodagholi et al. 2008; Dashtakian et al. 2002). In the present study, species were classified according to their growth habit followed using Raunkiaer’s life-forms system to characterize the flora of the Deh-Kohneh forest in Sepidan, Fars Province, Iran.

MATERIALS AND METHODS

The present study was carried out in the Deh-Kohneh forest, an enclosed area with 466 ha, in Sepidan, the northwest of Fars Province, Iran. The area as a genetic storage of wild pear species, located between 30 ° 21΄ 32˝ to 30° 23΄ 00˝north latitude and 51° 46΄ 35˝ to 51° 49΄ 41˝ east longitude. The minimum and maximum altitude is 2100m and 2554m,   respectively. This region has northern aspect and the slope is moderate (20%) to high (80%) (Averaged 40%) (Negahdarsaber, 1990). The hottest month is August with the average temperature of 20.8 ºC, while the coldest month, January, has the average temperature of -14.8 ºC. The range of annual average temperature in the study area is 9 to 15 ºC, while the annual precipitation ranged from 630 to 1050mm. The dry season is started from beginning of May through October (seven months). Geologically, part of Zagros Folded Belt has been formed as the result of the collision between Arabic and Eurasia plates. Sarvak formation is the main geological formation of the study area.  Asmari-Jahrom and Pabde -Gurpi are dominated formations in this region respectively. These formation resulted in carbonates soil (generates from calcareous parent material) in all of the specimens (Hamzehpour et al. 2010).

To study the area from a floristic and ecological point of view, specimens were collected in several field trips during the spring and summer 2015. Specimens were identified according to the common references (Boisser1870; Rechinger 1963; Townsend 1966; Zohary1973; Davis 1975).

Data was organized listing the species, their families, life-form and chorology.

Observations were made on aerial shoot reduction during unfavourably dry conditions and presence of underground storage organs. Species were classified as phanerophytes, chamaephytes, hemicrypt-ophytes, cryptophytes and therophytes according to the Raunkiaer method. We computed the proportion of species in each life - form class.

Fig. 1. Location of the study area.

RESULTS

In the study area, 97 species were recorded belonging to 79 genera and 25 families (Table 1). The families with the highest number of species werePoaceae(18 species), Rosaceae (11 species) and Apiaceae (10 species). Nine families were represented by only a single species. The results showed that hemicryptophytes (53.6% of species), phanerophytes (14.4%), therophytes (10.3%) and chamaephytes (8.2%) are the dominant life forms of the area respectively. The chorological studies indicated that the most species belonged to Irano-Turanian zone, while 4% were common species in both Irano-Turanian and Hyrcanian zones (Fig. 2).

Table 1. List of family, species, life form and chorotypes of Deh-Kohneh forest.

¹Life forms in the study area , Ph -phanerophyte, Ch – chamaephytes, He- hemicryptophytes, Th –therophytes, Gb –Geophytes Bulb, Gr- Geophytes Rhizome, Gt- Geophytes Tuber

²Chorotypes in studied area Irano-Turanian (IT) Irano-Turanian, Hyrcanian (IT-H)

Fig. 2. Life forms in studied area , Ph-phanerophyte, Ch – chamaephytes, He- hemicryptophytes, Th –Therophytes, Gb –Geophytes Bulb, Gr- Geophytes Rhizome, Gt- Geophytes Tuber.

Fig. 3. Frequency of plants families in Deh-Kohneh forest.