Study of medicinal plants in the geothermal area of Mount Seulawah Agam , Aceh Besar District , Indonesia

The area of mount Seulawah Agam is an area of active volcano paths that impact the appearance of volcanic symptoms, that will affect the species of plants that grow in the area. This study aims to determine the potential of medicinal plant species and their diversity in the geothermal area of Seulawah Agam, Aceh Besar district. The data collection was carried out using multiple square plots placed using stratified sampling based on the soil temperature zone at a predetermined. Each area is set on four impartial actions in systematic random. The name of the species and its individual quantity of each potential plant was documented and analyzed accordingly. Then, they were analyzed based on scientific journals and identification books for medicinal plants. Data analysis was performed using importance value index and Diversity Index. The study found there were 32 species of 21 families of medicinal plants were identified started from the growth rates of seedlings, saplings, poles, and trees. The medicinal plants' diversity index analysis at each growth rate is classified into the medium category. Based on literature studies, plants' parts are commonly used as medicines such as leaves roots, sap, bark, and flowers. Utilization can be used to treat a variety of diseases and illnesses, as well as a parasitic infection. The result shows that the geothermal area of Seulawah Agam in Aceh Besar district has excellent resources and potential for medicinal plants that become used for the benefit of the surrounding community: they need to be maintained so that they still be beneficial for future generations.


INTRODUCTION
Mount Seulawah Agam is an active volcano located in Aceh. The volcano has two craters, namely the Van Heuzst crater and the Simpago crater.The volcano is also surrounded by fumaroles, and hot springs [1]. Hot springs are an indicator of geothermal energy [2]. The hot springs area of Ie Jue Lamteuba is located at the foot of Mount Seulawah Agam, Aceh Besar district, Aceh. The site is still relatively natural and is rarely disturbed by human activities. Therefore, with such environmental conditions, many species of plants grow in the area that have adapted to the extreme enviroment [3].
Medicinal plants are plants used for their medicinal properties in many traditional health treatments and are also utilized in the form of modern medicines [4]. The use of traditional medicine is one of the primary health service programs. It is also an alternative to modern medicine in order to fulfill basic medical needs [5]. Treatment using traditional medicinal plants continues to this day and the practice has even increased in recent years [6].
The use of plants used as restorative materials for various diseases has been known and utilized for a long time by the community [7]. Knowledge of medicinal plants is based on practices and skills passed down from one generation to the next. The tradition of utilizing medicinal plants has been partly validated in this style. However, many of these traditional *Corresponding Author: dahlan@unsyiah.ac.id practices have not been scientifically recorded and disseminated through publications, especially the species of medicinal plants found in geothermal areas. This study is aimed at learning more about the diversity of medicinal plant species in the geothermal area of Seulawah Agam, Aceh Besar District

Place and Time of Research
This research was conducted in a geothermal area (Ie Jue hot springs), Lamteuba, Mount Seulawah Agam, Aceh Besar District ( Figure  1). The research was carried out from August 2019 to August 2020.

Data Collection
The data was collected in multiple square plots that were chosen based on the stratified sampling of soil temperature zones at a predetermined location (Figure 2).  For each plot that has been determined, plant species were observed at each growth level, namely seedlings, saplings, poles, and trees. The names and numbers of individuals of each plant species in the observation plot were recorded, then identified using plant determination key books from Steenis [8] and Tjitrosoepomo [9]. Subsequently, plants which had potential for medicinal properties were identified through a literature study using scientific journals and identification books of medicinal plant species. The books used included The Taxonomy of Medicinal Plants Collection (Aspan) [10], Efficacious Family Medicinal Plants (Wibisono) [11], The Smart Book of Medicinal Plants (Utami) [12], and The Indonesian Medicinal Plants Encyclopedia (Bangun) [13]. The journals that were used as references to identify medicinal plants can be seen in Table 4.   Measurements of abiotic environmental factors were carried out in each observation zone from 06.00 am to 08.00 am. The measured data on abiotic environmental factors included soil temperature, air temperature, soil humidity, air humidity, and sunlight intensity

Data Analysis
The data was analyzed using the Importance Value Index analysis (IVI) and the Shannon-Wiener diversity index analysis with the following formula: = High diversity [14].

Species of medicinal plants found in the Seulawah Agam geothermal area, Aceh Besar district
The species of medicinal plants found in the geothermal area of Seulawah Agam, Aceh Besar district, consisted of 32 species belonging to 21 families. These species' growth rates were categorized as saplings, poles, and trees ( Several seedlings grew well in open areas [15]. This is because open spaces make it easier for direct sunlight to penetrate the soil surface. This allows for a higher plant density because there are no tree canopies obstructing the sunlight in the area. Tree canopies make it virtually impossible for an understory to thrive, although there are exceptions in the form of shadetolerant plant species [16].
The Euphorbiaceae family is the most common family found among the plant species observed.
The species found at each growth level were Alstonia scholaris, Streblus asper, and Erioglossum rubiginosum. The presence of these species at each growth stage indicates that these species have good regeneration in the area. Alstonia scholaris is a species of medicinal plant that is used by the local community for hair care and enrichment [17]. Erioglossum rubiginosum is a species of plant utilized by the sub-ethnic Wolio efficacious to cure disease [18]. Meanwhile, Streblus asper is a medicinal plant that has been proven effective in treating hepatitis and ulcers [19].
. Importance value index (IVI) analysis was used to determine the dominant species in an observation plot [20]. The dominant species was defined as a species that can utilize its environment more efficiently than other species in the same place [21]. The index of the importance value of medicinal plants at each growth rate in the geothermal area of al Seulawah Agam, Aceh Besar district, can be seen in Table 2.
Based on Table 2, it is clear that Desmodium triflorum is the predominant medicinal plant species present in the area when compared with other medicinal plants in the seedling growth rate category. It comprises about 48.26% of the total species listed in the seedling category. Desmodium triflorum is a species of medicinal plant that is widespread in Southeast Asia, South Asia, and East Asia [22]. This is influenced by their ability to spread seeds that are very easily carried away by wind and water [23]. This plant species contains many diseases fighting compounds, including flavonoids, saponins, polyphenols, and trigonelline compounds24].
Streblus asper is the most dominant medicinal plant compared to other medicinal plants at the sapling growth rate, with a total of 29.84%. The importance value index illustrates that this species has more growth suitability than other plant species [25]. The leaves of this plant can be used to treat ulcers and hepatitis [19].
The species Alstonia scholaris and Streblus asper were discovered to be the most prominent species of plants in the pole growth rate category. Compared with others, they amounted to a combined total of 56.15% of the total category. These values indicate that these species play a vital role in the area because they have an IVI value of ≥ 15 % [20].
Melia azedarach is a species of medicinal plant that is the most dominant compared to other medicinal plants in the tree growth rate category, with a total of 73.69%. The high IVI value indicates that this species is prevalent because it has adapted to the environment better than other species [26]. The bark and leaves of Melia azedarach can be used as a medicine to treat high blood pressure and roundworms [19].

Diversity of Medicinal Plant Species in the Geothermal Area of Seulawah Agam, Aceh Besar District
The analysis of the diversity index for medicinal plants in the geothermal area of Seulawah Agam, Aceh Besar district, can be seen in Table  3.  Table 3, it can be seen that the diversity index of medicinal plants in the geothermal area of Seulawah Agam, Aceh Besar district at each growth rate is classified into the medium category. This indicates that each of the growth rates have a reasonably good level of plant growth stability in the area.
Species diversity can be used to measure community stability, such as the ability of a community to keep itself stable despite the disturbance of its components [27]. The species diversity index also shows the amount of variation in plant species in one place. The higher the diversity index value, the higher the diversity of species, and the ecosystem's stability in an area [28].

Utilization of the potential of medicinal plants in the geothermal area of Seulawah Agam, Aceh Besar District
The utilization of therapeutic plant potential based on literature review in the geothermal area of Seulawah Agam, Aceh Besar District, can be seen in Table 4. The table shows that the parts of plants used as traditional medicine consist of roots, bark, sap from bark, leaves, and flowers. Table 4 shows that the leaves of medicinal plants are the most widely used as a medicine. The leaves accumulate many secondary metabolites that are useful as medicines, such as alkaloids, tannins, essential oils, and other organic compounds stored in vacuoles or additional tissue in leaves such as trichomes [44].
The utilization of the leaves does not have a negative effect on the survival of medicinal plants. The part of the plant that needs to be limited in its use in medicine is the tuber, because the use of this part can kill the plant [49].
Many different benefits and uses of medicinal plant species were identified in the geothermal Seulawah Agam. Based on the literature study, these plants can be used to treat diarrhea, fever, dysentery, malaria, wounds, toothache, vaginal discharge, ulcers, hypertension, hepatitis, malaria, and many others.  Furthermore, the most common method used to process the plants was by boiling and pounding them. Boiling is very common and effective because people generally prefer to consume these plants after they have been boiled in water rather than consume them directly. The healing process is also much faster because the healing compounds of the plants are instantly released into the water and more easily processed by the body's metabolism when consumed [50].

CONCLUSION
The species of medicinal plants found in the geothermal area of Seulawah Agam, Aceh Besar district, consisted of as many as 21 families of 32 identified plant species starting from the growth rate of seedlings, saplings, poles, and trees. Meanwhile, the diversity index at each growth rate is classified into the medium category. Plants that were commonly used as medicines were identified based on literature studies, and the parts most commonly used in traditional medicines were the leaves, roots, sap, bark, and flowers. This study is expected to be used by the local community for critical data about the utilization of medicinal plant species found in the geothermal area of Seulawah Agam. This study can also be used as a reference for further research related to medicinal plants in the geothermal area.

ACKNOWLEDGMENT
The authors would like to thank all parties who have helped both in funding the research and in the process of collecting research data in the field. Syiah Kuala University funded this research, Ministry of Research, Technology, and Higher Education through the 2020 Masters Thesis Research Fund with Contract Number: 44 / UN 11.2.1 / PT.01.03 / DPRM / 2020.