Mangroves species diversity and their use as medicinal plants by coastal communities of Pesawaran Lampung

As a means of adaptation to extreme habitats, mangrove plants produce a variety of secondary metabolic substances that have the potential as herbal medicines. Empirically, coastal communities have utilized and proven the medicinal properties of mangrove plants. The study’s objective was to determine the species diversity of mangrove plants and their use as herbal medicine in the Coastal of Pesawaran, Lampung Province. Mangrove plant diversity was obtained through vegetation analysis and the diversity index calculation. The use of mangroves as medicine was obtained through in-depth interviews followed by descriptive analysis and calculation of species use value, plant part value, and fidelity level. The results showed that the mangrove forest on the Pesawaran Coast consisted of 21 mangrove species from 12 families, with a moderate diversity index (H’= 1.9312). Most of the users of mangrove plants as medicine ethnically were Bugis (55%), aged over 40 years (62.5%), have an income ranging from 100--167 USD / month (54%), and have secondary education (37.5%). The community uses Avicenia alba as an antiseptic, Acanthus ilicifolius as an antiseptic, Rhizophora apiculata as an antiseptic and analgesic, and R. stylosa as an antiseptic and anti-rheumatism. The Species use value of R. apiculate was the highest (0.25), while the other three species only reached 0.125. Leaves and bark were parts of the plant used as medicine, where leaves have the highest plant part value of 91.67%, and the remaining 8.33% was bark. The highest fidelity level was obtained by R. apiculate as an antiseptic (88%), followed successively by R. stylosa as an antiseptic (50%), R. stylosa as an analgesic, and A. alba as an antiseptic (13%).


Introduction
Biodiversity is vital for human life in providing goods and services to meet the needs.Biodiversity provides food, medicine, ornamental flora, future resource reserves, gene, species, and ecological diversity [1].At least 40% of the world economy is highly dependent on biological products and ecosystem services [2].Biodiversity provides an important resource for the development of herbal medicines.80% of the world's population, or more than 4 billion people, still use herbal medicines as a main priority or a companion treatment for health problems [3].Medicinal plants are the most frequently used therapeutic option in conventional and complementary medicine worldwide [1].The popularity of herbal medicines has increased significantly in the last decade, driven by increased interest in alternative medicine and the use of natural products.Ervina and Ayubi [4] reported that traditional herbal medicines are believed to have lower side effects and are cheaper and easy to obtain.From the point of view of medical practice, the phytochemicals contained in herbal medicines are believed to have a better response in the human body than the synthesis drug [5].These advantages have boosted the popularity of herbal medicine.
Medicinal plants can be found in various ecosystems [6].However, about 90% of medicinal plants are found in forest habitats, and only 10% grow in other landscapes, such as open grasslands and agricultural grasslands, as well as in and around freshwater bodies [7].Furthermore, Supriyanto et al. [8] suggested that medicinal plants can also be found in mangrove ecosystems.Mangrove plants are unique since they can grow and adapt to specific habitats.As a plant that lives in an extreme 1255 (2023) 012027 IOP Publishing doi:10.1088/1755-1315/1255/1/012027 2 environment, mangrove plants are saturated in stressful conditions, and therefore in order to sustain their life, mangrove plants produce various secondary metabolic compounds as an adaptation in dealing with environmental stress [9].Secondary metabolic compounds produced by mangrove plants have the potential to be used as bioactive that are beneficial to human health.
Mangrove plants grow in coastal areas that are inundated at high tide and puddle-free at low tide, which are tolerant of high salinity [10].Salinity is a vital factor that regulates the growth and distribution of mangroves [11].Mangroves are facultative halophytic plants, which means that mangroves need fresh water physiologically, while ecologically, the growth of mangroves in salt water is to avoid competition from non-halophytic plants [12].
According to Mahmiah et al. [13], as a country with a high diversity of mangrove vegetation, Indonesia has various potentials for mangroves that have not been widely explored, especially as raw materials for medicine.Regarding the high import value of medicinal raw materials, which reaches 90% of the total national need [14], if the community could fulfill some of their medicinal needs, it would contribute to economic development through the independence of medicinal raw materials.According to Suliasih [15], the government continues to develop and use herbal medicinal raw materials to reduce dependence on imported medicinal raw materials.
Purwanti [16] reported that the identification and documentation of the use of mangroves as medicinal plants are as important as the preservation of these mangroves itself.According to Oruh and Nur [17], one of the direct benefits of mangrove forests is that the community can use mangroves as medicinal plants.Ratnawati et al. [18] reported that with the benefits that are felt directly by the community, there would be a concern for the existence of mangrove forests.Furthermore, Oprasmani et al. [19] reported that increasing public awareness and concern for mangrove forests will encourage community involvement in mangrove forest conservation.
One of the important mangrove areas in Lampung Province is Sidodadi Village, Teluk Pandan District, Pesawaran Regency.The Mangrove of Sidodadi is strategic because it is a buffer zone for the Coastal of Lampung Bay, where the City of Bandar Lampung has a population of 1,209,937 [20].Mukhlisi et al. [21] reported that in Sidodadi, 22 species of mangrove trees were found, 10 of which were major mangrove categories (true mangroves), 4 minor mangrove species, and 8 associated mangrove species.However, the massive development in Lampung Bay's coastal area has impacted changes in mangrove vegetation.Recent studies are needed to determine changes in the diversity of mangrove species in the Sidodadi mangrove within 10 years.Furthermore, until now, the utilization of mangrove biodiversity in the village has never been reported.As Rosyada [22] stated, data and information regarding the use of mangroves as herbal medicine in Indonesia have not been well documented.
As a strategy to support the development and use of medicinal plants, as well as to increase the role of the community in mangrove conservation, data and information related to the diversity of species and the use of mangroves as herbal medicine is very important to be documented and studied scientifically to serve as a basis for policy-making.The study's objective was to identify the biodiversity of mangrove plant species and the traditional use of these plants as herbal medicines by Coastal Communities in Pesawaran District, Lampung Province.

Sampling
The research was conducted in November 2022 in Sidodadi Village, Sub-District of Teluk Pandan, Pesawaran District.There are two types of data in the study, namely data on the diversity of mangrove species and data on the use of mangrove plants as herbal medicine by the community.The diversity of plant species in mangrove forests was analyzed using vegetation analysis.The community's use of mangrove plants as herbal medicine was identified through interviews with key persons.
Sampling for vegetation analysis was carried out using the cluster sampling method.This method was chosen because, based on preliminary observations and map studies, it is known that there are variations in the Pesawaran Coastal area in terms of substrate, fresh water supply, and current sea status.These three factors are closely related to plant species in mangrove forests.Based on the initial study, three observation stations were assigned to each cluster.At each station, an observation plot is placed in the form of a lane with a length equal to the thickness of the mangrove at that station.The starting point of the lane is placed on the outermost part of the mangrove vegetation closest to the open sea, and then a track line is made from the starting point, perpendicular to the shoreline to ending in the nearshore area (land).In each lane, observation plots measuring 10m x 10m were placed alternately on the left and right of the lane, with a distance of 10m between plots.The plot method is a combination of the transect method and the plot method [23].Placing sample plots along an elongated path aims to see the profile and ecology of mangrove vegetation based on the existing zones.
Respondents of mangrove plants using herbal medicine were drawn using snowball sampling.This method was chosen because not all coastal communities know and use mangrove plants as herbal medicine.Respondents in this study are devoted people who know and use mangrove plants as traditional herbal medicine.The snowball sampling method is suitable for this study because this method can reach respondents who are difficult to find [24].

Data Collection and Analysis
Data on plant species identified using the Guide to Introduction of Indonesian Mangrove [25] were collected in each observation plot.Observational data is tabulated to facilitate the analysis.The composition of mangrove vegetation species was analyzed using descriptive analytic methods.The plant species constituent of mangrove vegetation is grouped according to the families, groups (true mangroves/associated mangroves), and conservation status based on the International Union for Conservation of Nature (IUCN) category.
The diversity of plant species constituent the mangrove vegetation was analyzed using the Shannon-Wiener diversity index (Shannon's index) [26] with the following formula: Where p is the proportion (n/N) of individuals of a particular species found (n) divided by the total number of individuals found (N), ln is the natural log, Σ is the number of calculations, and s is the number of species.
Information about the types of mangrove plants, parts of the plants used, and how to use them was collected from each respondent through structured interviews using a questionnaire.The data and information obtained were then analyzed to find out several parameters related to the use of medicinal plants [27], namely: a. Species Use Value (SUV) Where SUV is the species use value, ƩUV is is the number of species benefits stated, and ni is the number of interviewed respondents.b.Plant Part Value (PPV) Where PPV is the plant part, RU is the total number of plant uses reported, and RU plant part is the number of uses reported per part of a medicinal plant.c) Fidelity Level (FL) 4 Where FL is the confidence level, Np is the number of respondents who mentioned the species for a particular use, and N is the total number of respondents who mentioned the species for various uses.

Species of mangrove vegetation composition
Knowledge regarding the composition of mangrove species in an area is an important prerequisite for understanding the structure and function of mangroves and their biogeographical proximity, conservation, and management strategies [11].The types of mangrove vegetation constituents in Sidodadi Village are presented in Table 1.Twenty-one mangrove plant species originate from 12 families in the Sidodadi Village area, Pesawaran.Of the 21 species, 10 are categorized as true mangroves, and 11 are associated with mangroves.Associated mangroves are species often found in mangrove environments but not exclusively in estuarine areas because they can also be found outside mangroves [25].Associated mangroves generally grow in the land zone.The inland mangrove zone has a higher species richness than other zones [28].
Based on Table 1. it is known that the number of mangrove species in Sidodadi Village is high.The high diversity is due to the area's site status, which varies.The Sidodadi mangrove area has three groups of site status: (1) around the estuary with fresh water intake and mud substrates, (2).Sandy substrates area where there is no fresh water intake, and (3) Sandy mud substrates area, far from rivers.These three site statuses provide diversity in terms of salinity and substrate, which impacts the diversity of species that can grow and adapt to the site.The more diverse the site status, the more diverse the species of mangroves will be in the area.Furthermore, Mukhlisi [21] states that environmental factors that influence the survival of mangrove plants are the supply of fresh water from rivers, the suitability of each habitat species to climate, geographical status, salinity, and substrate stability.
There were more associated mangrove species than true mangrove species in Sidodadi Village, which indicated that the succession or species dynamic process had reached a climax.The climax status is marked by the change from a true mangrove community to a mangrove association due to the improvement in the quality of the site environment.The succession that occurred in Pesawaran Lampung is closely related to environmental changes.It is suspected that sedimentation originating from small rivers has formed land with the help of mangrove roots and resulted in environmental status becoming more conducive for the growth of associated mangroves.Following the statement of Heriyanto & Subiandono [29], the interaction between rivers and sea waters influences the dynamic diversity of mangrove ecosystems, where mangrove vegetation will continue to grow and develop until it experiences succession in the form of silt, which slowly turns into semi-terrestrial areas.

Diversity index
The diversity index is a vegetation parameter used to compare various plant communities, primarily to study the effects of disturbance by environmental or abiotic factors on the condition of plant communities.The results showed that the Mangrove species diversity index in Sidodadi Village was 1.9312.This value is categorized as the medium based on Odum's [26] criteria.The medium diversity index indicates that the mangrove ecosystem in Sidodadi Village has sufficient productivity, balanced ecosystem conditions, relatively stable water conditions, and moderate ecological pressure.This result aligns with the changes in the types of mangrove vegetation that have not changed much from 2013 to 2023 [21].
The value of the diversity of a community is very dependent on the number of species and the number of individuals found in the community.The species diversity of a community will be high if the community is composed of many species and no species dominates.Conversely, a community has a low species diversity value if the community is composed of few species and there are dominant species [30].Naturally, the diversity of mangrove forest species is lower than land tropical forests.However, mangrove forests have a unique structure and function.Therefore, they can survive in extreme environments in the tidal zone [31].Mangrove ecosystems also have high primary productivity.Nevertheless, the ecosystem could easily damage if there are disturbances, especially anthropogenic ones [32].The diversity of species and the growth of mangroves are influenced by the supply of fresh water from rivers that empty into the sea and the suitability of the habitat for each type of climate and coastal geographical status [33].

Socio-economic status of the sidodadi village community
The people of Sidodadi Village who live around the mangrove forest are ethnically dominated by Bugis (55%), Javanese (11%), Sundanese (11%), Serangnese (11%), and other ethnic groups (11%).Most of the community's education levels were junior high school (37.5%), high school (25%), elementary school (25%), never graduated from school (9.2%), and university (1.3%).The average income per family ranges from Rp. 2,000,000-3,000,000 per month, most working as fishermen and farmers.Most (62.5%) of the people who know and use mangrove plants as herbal medicine are adults (over 40 years old).The phenomenon illustrates that knowledge related to mangroves belongs to the older generation.Only a small proportion (12.5%) of the younger generation (21-30 years) know about the efficacy of mangrove plants as medicinal plants.It indicates that the knowledge transfers about mangroves as medicinal plants from older to younger generations are not going well.Qasrin et al. [34] say this happens because the younger generation prefers modern synthetic drugs considered more practical.In line with that, Ani et al. [35] reported that knowledge about traditional medicinal plants was limited and only passed down from generation to generation.Furthermore, Nurislaminingsih et al. [36] reported that limited ancestral memory is one of the obstacles to preserving medicinal plant knowledge.

Species use value (SUV)
Mangrove plant species used as medicine in Sidodadi Village are Rhizophora apiculata, Rhizophora stylosa, and Avicennia alba.R. apiculata is the most popular and widely used of the three types.A complete comparison of mangrove species used as medicinal plants is presented in Figure 1.

Figure 1. Species Use Value(SUV) of mangrove plants as medicinal plants in Sidodadi
Based on Figure 1. it can be seen that R. apiculata has the highest SUV among other species.It is presumably because R. apiculata is the most dominant species in the Sidodadi area.Generally, plant species that are easy to obtain will have a high use value.In addition to being easy to find, R. apiculata is indicated to have many bioactive ingredients as well.Therefore, it has many benefits for treating various diseases and is widely used by the community.As Berawi and Marini [37] reported, R. apiculata is widely used by coastal communities as medicine because it contains many active ingredients such as flavonoids, triterpenoids, steroids, saponins, and tannins, and almost all of its parts of the plant contain natural antioxidants which are effective in preventing cancer.Furthermore, Othman et al. [38] reported that R. apiculata contains a lot of alkaloids, glycosides, essential oils, and other organic compounds used as medicines for various diseases, both infectious and non-infectious.
The abundance of R. apiculata in the Sidodadi area is closely related to the site status.The Sidodadi area has fresh water intake from small rivers.Therefore, the mud substrate is not too dominant and mixed with sand.This type of substrate is very suitable for R. apiculata growth.Othman et al. [38] state that the dominance of R. apiculata generally occurs in areas with sufficient fresh water intake.Furthermore, Jalaludin et al. [39] reported that ecologically R. apiculata grows well in transitional soil conditions between mud and sand substrates.

Plant part value (PPV)
The leaf is part of the plant most widely used by the Sidodadi community as herbal medicine.More than 75% of the people use mangrove leaves as medicinal plants, while the other parts are underutilized.The complete PPV calculation results for the three species of mangrove medicinal plants in Sidodadi are presented in Figure 2.  Based on Figure 2 known that the leaf is the most widely used part compared to other organs with a value for each species, namely 100% for A. alba, 75% for R. stylosa, and 100% for R. apiculata.In line with the reports of Roudotuljannah and Azizah [40], the organs most widely used from medicinal plants are the leaves.Furthermore, according to Wahidah & Husain [41], people believe leaves are plant organs that contain the most bioactive compounds and are easy to process.The high bioactive content in leaves is because leaves are the tissue where important compounds accumulate during photosynthesis [42].According to Mutik et al. [43], mangrove leaves contain various secondary metabolite compounds such as alkaloids, phenols, saponins, terpenoids, and steroids.The high use of leaves as herbal medicine is influenced by the abundant availability of leaves, which are always available at any time and do not depend on the season, such as flowers and fruit.In addition, Nisyapuri et al. [44] reported that leaves are the easiest part to obtain from a plant.Even more, harvesting leaves does not cause plant death.

Fidelity level (FL)
The Sidodadi Village community's fidelity level regarding using mangrove plants as medicine is generally low (less than 50%).There is only 1 efficacy of R. apiculata, which is believed by the community with a high level of trust (88%), namely as a wound medicine or antiseptic.The full value of the Fidelity level of the community in Sidodadi Village towards mangrove plants as medicine is presented in Table 2. wound medicine /antiseptic 88% The fidelity level of the Sidodadi Village community towards healing diseases by using mangrove plants as an antiseptic is high, while for other treatments, it is still low.The fidelity level of the community to healing a disease using herbal medicines is strongly influenced by the community's knowledge of medicinal plants [45].The higher the public's knowledge about medicinal plants, the more confidence they will have in healing diseases through herbal medicine.The level of education of a community will generally affect the level of knowledge, including knowledge about medicinal plants, the higher the level of education, the easier it is for the community to receive and understand information [46].Fidelity level towards plants as herbal medicines is also influenced by the various advantages of herbal medicines, such as common side effects, cheaper, ease to obtain, and availability locally.According to Kuna et al. [47], traditional herbal medicines are in greater demand because they have lower side effects.In addition, according to Shahrajabian et al. [48], traditional medicinal plants are increasingly in demand because they are cheaper, available in nature, and can be consumed directly or processed into herbal medicines.

Conclusion
The mangrove forest in the Sidodadi Village, Pesawaran Regency, comprises 21 plant species from 12 families.Based on its diversity, the Sidodadi Mangrove has medium diversity with a value of diversity index of H'= 1.9312.Most of the users of mangrove plants as medicine ethnically were Bugis (55%), aged over 40 years (62.5%), have an income ranging from 100--167 USD / month (54%), and have secondary education (37.5%).The community uses Avicenia alba as an antiseptic, Acanthus ilicifolius as an antiseptic, Rhizophora apiculata as an antiseptic and analgesic, and R. stylosa as an antiseptic and anti-rheumatism.The Species use value of R. apiculate was the highest (0.25), while the other three species only reached 0.125.Leaves and bark were parts of the plant used as medicine, where leaves have the highest plant part value of 91.67%, and the remaining 8.33% was bark.The highest fidelity level

Figure 2 .
Figure 2. Plant Part Value (PPV) of mangrove medicinal plants in Sidodadi Village.

Table 1 .
The composition of mangrove vegetation species in the Sidodadi Village

Table 2 .
Fidelity level of the community in Sidodadi Village towards mangrove plants as medicine