Traditional lore on the healing effects of therapeutic plants used by the local communities around Simien Mountains National Park, northwestern Ethiopia

Background Simien Mountain National Park is a world heritage site with spectacular landscapes and rich in floral diversity. Exploring the plethora of conventional wisdom regarding therapeutic flora for sustainable use and drug development is a timely endeavor. Thus, the present study was aimed at investigating therapeutic plant uses and conservation practices by the local communities dwelling in the vicinity of the Park. Methods Eighty randomly selected general informants and 20 purposefully selected key informants were used to collect the traditional lore from 10 purposefully selected kebeles that border the Park. Data were collected using face-to-face interviews, guided field walks, group discussions and market surveys. Descriptive statistics were used to analyze the basic information collected from the informants. An independent sample t test was computed to compare the knowledge variations among different informant groups. Clustering and ranking techniques were employed to validate traditional wisdom of informants. Results Significant differences in traditional wisdom (P < 0.05) were observed only between general and key informants. Hundred thirteen therapeutic plant species belonging to 56 families were recorded. Asteraceae was the most species-rich family (10%). The majority of therapeutic species were collected from the wild (77%). Herbs and roots were the most preferred habit (47%) and plant parts (37%) for remedy preparation, respectively. Pounding was the most common preparation method (50.1%). The most frequently practiced route of administration was the oral route (48.1%). The highest Informant Consensus Factor (ICF) value (84%) was recorded for respiratory and febrile illnesses. Rumex nepalensis was the most preferred for the treatment of wounds, and Olea europaea subsp cuspidata was the first-ranked multipurpose plant. Conclusion The Park is rich in therapeutic species serving as a refuge for many endemic and endangered species associated with the local community rich medicinal traditional lore. Erosion of therapeutic plants, verbal transfer of the traditional wisdom and young generation negligence in acquiring traditional lore led to the deterioration of the long tradition of using therapeutic plants for health care. Endangered multipurpose therapeutic plants like Echinops kebericho should get conservation priority. Therapeutic plants with the highest ICF and fidelity level could be candidates for drug development.


Introduction
Starting from the time immemorial, local communities in Africa exercise traditional medicine as the primary healthcare system over modern medicines due to its affordability, acceptability and easy access to traditional plants [1].In East Africa, including Ethiopia, traditional medicine is the dominant and most popular system of health care, used by about 80% of the population [2].Matching to this, Ethiopia harbors a great diversity of geology, land forms, soils and climate that makes it a floristically diverse nation [3] that favors medicinal plant growth and utilization.As a result, Ethiopians are largely relied on their natural environments for their basic needs and health care.Thus, use of medicinal plants for health care is the long tradition of the Ethiopian people.
However, the documented medicinal plants in the country are limited compared to the floral diversity and the existing multiethnic and cultural diversity of the people as well as the long history of using medicinal plant for health care [4].On the other side, the indigenous knowledge is passed verbally from generation to generation that can be easily deleted from the mind.In addition, medicinal plants and the associated knowledge are being seriously depleted due to deforestation, environmental degradation and acculturation that have been taking place in the country for quite a long time [5,6].This could ultimately result in the weakening of primary healthcare services.
Simien Mountains National Park (SMNP) and the surrounding areas are magnificent and spectacular land escapes.In honor of its exceptional biophysical features and unique combination of biodiversity with many endemic and endangered species, the park was inscribed on the UNESCO World Heritage List in 1978 [7].Taking its international significance into consideration, except for the traditional lore on therapeutic plant species, a great deal of information has been published about the park as it draws the attention of scholars from various fields [8][9][10][11][12][13][14].
However, the park, like other regions of the nation, is still challenged by several anthropologic factors, such as overgrazing, agricultural encroachment and selective removal of plant species (SMNP Office report, 2020).In addition, SMNP is much more sensitive and vulnerable to the impacts of climate change since the park is included in the afromontane and afroalpine ecosystems, which are exceptionally vulnerable to climate change.Rising temperatures, changing rainfall patterns and an increased frequency of extreme weather events are affecting the park's ecosystems, including the distribution and survival of plant and animal species.Though the communities around the park have a long tradition of using therapeutic plants for their health care, the loss of indigenous flora and therapeutic plants with the associated indigenous lore is, also, one of the major challenges facing the park.Before the accelerated ecological and cultural transformation totally distorted the physical entities and the associated knowledge base, scientific documentation of traditional lore with therapeutic plants was a timely endeavor.It was expected that SMNP, with its vast microhabitats caused by its extraordinary topographic variability, would call for new exploration and recording of therapeutic plants, which could be commendable for this work.Therefore, the objectives of the present work were: (a) to document the long tradition of using therapeutic plants for health care; (b) to assess major threats to therapeutic plants; (c) to document the traditional practices of conserving therapeutic plants; and (d) to identify novel practices regarding the use of therapeutic plants among the residents living in the vicinity of the park.
The Park is the highest regions of the Ethiopian Plateau, extending from 2000 to over 4,550 m a.s.l., i.e., Ras Dejen Mount, Ethiopia's highest peak point [16].The park is an area of great diversity and scenic beauty and referred to as the "roof of Africa." The unique geological formation of the mountains with the extensive erosion of the basaltic layers over a long period of time led to the formation of different land forms that make up the spectacular landscape of SMNP (Fig. 2).The presence of unique landscapes and biodiversity made SMNP a World Heritage Site in 1978 (SMNP Office report, 2020).
The climate of the Simien Mountains is quite different from the surrounding lowlands.Analyses of metrological data obtained from Ethiopian Meteorological Agency (EMA) Debark and Chenek stations (from 2003 to 2022) showed a unimodal rainfall pattern with variations in attitude.The mean annual rainfall for Debark and Chenek was 1145 and 1445, respectively.The area has low rainfall from October to March, which gradually increases to the peak period, June and August (Fig. 3).The mean annual temperature of Debark and Chenek was 14.2 and 9.1 °C, respectively.The coldest months are from October to January, whereas hotness occurs in April and May.
Vertically the vegetation of the mountains is classified into four.These are afroalpine, ericaceous belt, afromontane and woodland (Fig. 4).The afroalpine vegetation is largely made up of grasses and sedges covering the undulating plains, interspersed with Lobelia rhynchopetalum, and other herbaceous species.Small trees of Hypencum revolutum mixed with Ericas are sparsely distributed in less harsh areas.The ericaceous belt is a narrow zone between afromontane and afroalpine, ranging from 3000 to 3200 m altitude mostly occurs on the escarpment.The physiognomy of the Erica belt is largely characterized by the dominance of Erica species, Hypericum revolutum and perennial herbs such as Thymus schimperi.The afromontane vegetation is found in the area between 2,000 and 3,000 m a.s.l., in the less steep parts of the escarpment.
Original afromontane forests are largely destroyed by human activities with the remaining patches confined to inaccessible areas [16].Characteristic tree species in the forest patches include Prunus africana and Olea eurpea subsp.cuspidata with the prevalent climbers such as Jasminum abyssinicum.Moreover, the lowest areas contain savannah type wood and bushland.

Study site and informant selection
After conducting a reconnaissance survey, ten kebeles (the smallest administrative unit), among 42 buffering kebeles in the park, were selected for traditional lore data collection.Selection was made purposefully based on their relatively high plant diversity, altitudinal ranges, agroecology, traditional medicinal practices and the presence or absence of health facilities.Thus, as they met the selection criteria, Adebabay Tsion, Adisge, Bashaye, Agdamiya, Dibebahir, Guayint, Lon, Sakiba, Zakileta and Zebana were selected as study sites (kebeles) (Fig. 5).
A total of 100 informants (70 males and 30 females) aged between 20 and 90 years were selected from the sampled kebeles.Of these, 80 were selected randomly as general informants, and the rest 20 were selected purposefully as key informants based on the recommendations of local healers, elders and park rangers following [17].Information on the study locations and informants' demographic profiles are summarized properly (Table 1).Prior to commencing the interview, all participants were informed about the aim of the

Traditional lore data collection
Data were collected through face-to-face or individual interviews, focus group discussions and guided field walks with.Field visits were done in different seasons with the aim of gathering medicinal plants during their flowering time.Interviews were conducted in Amharic language and run independently to make informants free to deal with secret information.During data collection, informants were communicated twice to validate the consistency and reliability of the information provided by them.Face-to-face interviews were used to collect secret or sensitive information that is considered personal, Information was gathered based on semi-structured questionnaires contained in a checklist that covered key topics regarding the informants' profile, medicinal plants, parts used, method of remedy preparation, remedy dosage, route of remedy administration, antidotes or     (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39), Yg Elder, El); male, M, female, F; Religion (Christian, Ch, Muslim.Mu).Regarding to ethnicity and language all interviewees belong to Amhara ethnic group and speak Amharic language.ingredients used, interaction of healers with the forest, ailments treated, marketability, threats and conservation practices of medicinal plants [17].Focus group discussions (FGDs) were held by using 6-8 key informants selected purposefully from the different study sites, age groups and sexes.The discussions were used for ranking medicinal and other uses of medicinal plant species, enriching and confirming the reliability of the qualitative description of the information obtained during the face-to-face interview.Thus, it allows researchers to collect rich and in-depth qualitative data that helps to gain a deeper understanding of the complex relationships between people and plants within that specific cultural contexts, ultimately contributing to the conservation of traditional knowledge and the sustainable use of plant resources.On-site confirmations of the reliability of the information obtained during face-toface interviews, with the help of practical demonstrations with informants, were also conducted through guided field walks.In addition, information regarding medicinal plant names, habits, habitats, status and market demand for medicinal plants was collected using a guided field walk with the informants.The medicinal plant specimen collections and photographs were taken during guided field walks.Local market surveys were carried out at three comparatively large market places in the study area: Debark, Qayit (Janamora) and Mekane-birhan (Janamora's main city) local markets, so as to assess the marketability (selling and buying) of medicinal plants which is ultimately related to the survival of medicinal plants.Voucher specimen collections were done with the help of traditional healers.Specimens were air-dried, numbered, labeled, pressed, identified and deposited at the University of Gondar Herbarium.Identification of plant specimens was done both in the field and at the herbarium using floras of Ethiopia and Eritrea.

Data analyses
Traditional lore variations and dynamics on the use of medicinal plants by males and females in different age groups and general and key informants were compared using a t test and one-way ANOVA (analysis of variance) at a 95% confidence level between means by using SPSS (Statistical Package for the Social Sciences) version 20.Basic traditional lore data such as plant habits and parts used, life form, source of medicinal plants, method of remedy preparation, route of remedy administration, ailments treated, threats and conservation practices of medicinal plants were analyzed via descriptive statistics such as percentage, frequency distribution and graphs as recommended by [17,18].
In addition, ethnobotanical data clustering and ranking methods such as informant consensus factor (ICF), preference ranking, direct matrix ranking and fidelity level were carried out to ensure consistency and priority.ICF was computed for various categories of ailments in order to assess the level of agreement among informants regarding their knowledge of medicinal plants within each category.To determine ICF values, diseases were divided into nine groups, more or less, based on the international classification of diseases (ICD) [19], after which the ICF value was determined for each category.ICF values for nine disease categories were performed to understand knowledge homogeneity among informants for each disease category using the formula ICF = Nur-nt / Nur − 1 [20], where Nur = number of use citations in a particular ailment category and nt = number of medicinal plant species used for any ailment category.
A preference ranking exercise was conducted to evaluate the degree of preferences or levels of importance of eight selected medicinal plants used to treat bleeding using seven randomly selected key informants following [17].Each informant assigned the highest value (7) for the most preferred plant species against bleeding and the lowest value (1) for the least preferred species.Finally, scores given for each plant species by the informants were summed and ranked.Such ranking helps to understand which plants, among the listed once, are considered more valuable to treat the specific disease mentioned, in this case bleeding.The use diversities of therapeutic plants were computed by direct matrix ranking (DMR).During the DMR exercise, seven widely utilized multipurpose therapeutic plant species were compared by selected key informants following [17].The plants were listed by the selected key informants to assign use values to each species (5 = best, 4 = very good, 3 = good, 2 = less used, 1 = least used and 0 = not used).Accordingly, the scores assigned by key informants were added and ranked.
Fidelity level (FL) was used for species mentioned over 30 times to check their efficacy for a specific aliment following [21].It was calculated as FL (%) = (Np/N) × 100, where Np is the number of informants that claim the use of a plant species to treat a particular disease and N is the number of informants that use the plants as a medicine to treat any disease, as stated by [22].Fidelity level helps to measure the extent to which a plant is faithfully and consistently used for a specific use category, in this case treating a particular disease.Jaccard's coefficient of similarity (Js) was used to compare the current study with other ethnobotanical studies in other parts of the nation.It was calculated using the formula Js = c/ (a + b + c), where a represents the number of plants in an area "a," b represents the number of plants in area "b," and c represents the number of plants common to areas a and b.

Relation of traditional lore and the natural environment
An independent sample test showed significant differences (P < 0.05) between traditional healers and general informants on the number of medicinal plant species they listed and associated use reports (Table 2).Similar results were reported by [23][24][25].The significant difference observed between key and general informants could relate to the impact of age-old experience and the maximum degree of secrecy in using medicinal plants in the former and modernization in the latter.Based on their experience and assessing previous documents [23], told us community members who have greater contact with medicinal plants are more knowledgeable about the therapeutic uses of the plants than those with intermittent contact.Some informants even reported that several key informants are specialized for treating particular diseases like rabies and hepatitis (in local language it is called "YEWOFIE").
The high level of indigenous knowledge contained in traditional practitioners may also be attributed to environmental advantages, cultural practices and public health services.Simien Mountains massifs, owing to their unique geological formation, wide altitudinal range and diverse topographic features, are endowed with a spectacular landscape.The combined effect of these factors gifted the mountain ecosystems with rich biodiversity, making the area part of the eastern afromontane biodiversity hotspot.SMNP, a portion of the massif, was declared as a World Natural Heritage Site by UNESCO in 1978 in honor of its unique combination of biodiversity and scenic beauty.The park covers a wide altitudinal range from below 2,000 m in the deep valleys to over 4,500 m a.s.l. in Ras Dashen (the highest peak in Ethiopia).Its topography, with gorges, crests, rocks and flat areas, results in a rich mosaic pattern of various habitats that favor the distribution of various species and increased isolation by impeding dispersal and pollination that ultimately result distinct species.The overall effect of these factors promotes to high species diversity with rich endemic elements.Thus, previous studies reported over 525 flowering plants [14,16].Therefore, higher species richness and diversity in the study area increase the chance of practitioners to prescribe the right remedy to their patients.
Christians, Muslims and Jews have lived in the SMNP and its environs for many generations, sharing strong cultural and economic ties.Jewish people have a strong connection to the environment and a tradition of using it for a variety of purposes, including the use of herbal medicine.As part of Israel's effort to gather its citizens from all over the world, the Jewish people have now largely been relocated from the area.However, their traditional wisdom and indigenous practices are left behind and become the wealth of local residents of the study area.
In the five districts sharing SMNP, there are 200,941 people and 54,576 households getting health services from three hospitals, 35 health centers and 100 posts.The most common public health issues that residents surrounding the park experiences include heart disease, hypertension, respiratory diseases, skin problems, injuries, diabetes, conjunctivitis and other eye infections (North Gondar Zone Health Office report, 2021).Access to infrastructure is limited in comparison with the national level.By deploying two female health extension workers in health posts at each kebele across the nation, government of Ethiopia launched disease prevention Health Extension Program.Nevertheless, the program did not bring the desired output in the primary health care of the SMNP residents.Female extension workers find it difficult to cross the undulating terrains of the dissected mountains' topography to provide house-to-house health services.Thus, traditional healers, with a profound knowledge on local plants and diseases to be treated, are the only health workers immediately available to the inhabitants.In short, rich biological resources, strong cultural ties to the local resources, remote location and challenging topographic features for accessing modern health facilities make the settlers have a long tradition of using herbal traditional medicines as a primary health care.
Though males reported a higher number of therapeutic plants than females, the t test did not show a significant difference (P > 0.05) (Table 2).This finding is consistent with some other studies conducted in Ethiopia [24,[26][27][28], who claimed the absence of a significant relationship between gender and the number of medicinal plants listed by them.A higher number of plants reported by male informants than females, on average, could be related to the traditional flow of information along the male line in the nation [23].On the contrary, this study Table 2 Statistical test of significance and independent t test on the number of medicinal plant mentioned by informants disagrees with the previous reports by [25,29] that highlighted a significant knowledge difference between the sexes.Besides, no significant difference (P > 0.05) was observed between the age groups (20-39 and 40-90 years) and the number of medicinal plant species they listed, as well as the respective uses they reported (Table 2).However, on average, elders mentioned greater number of medicinal plants and their uses (Table 2).This demonstrates that the therapeutic plants lore is still strong with elderly people [23] and lack of interest in acquiring the wisdom in young generation.
The present study highlighted the good knowledge base of residents on herbal remedy.Verbal communication, as reported by informants, was the most common way of transferring the traditional wisdom (83%) among the family members especially to the elder son.During transfer, secrecy is expected to be maintained in the family circle [23].Wisdom obtained through other means was minimal (Fig. 6).In addition, some informants reported that they gained knowledge of medicinal plants by following traditional healers behind (without the permission of the healer) during medicinal plant harvest.Furthermore, a Muslim healer believed that their traditional wisdom was a gift from Allah or through religious learning.
The informants worried about the threat of indigenous knowledge as a result of younger generations reduced interest to learn about the medicinal plants due to the impact verbal transmission and modern education.Similar findings were also reported in other parts of Ethiopia [23,30].As a result, the absence of documented medicinal plants knowledge coupled with lack of interest in younger generation to learn indigenous wisdom threats future use of medicinal plants.

Medicinal plants diversity in SMNP
A total of 113 medicinal plant species belonging to 92 genera and 56 families were documented.Except for one species, Junperus procera, all other medicinal plant species collected in the study area were angiosperms, with 90.3% being dicots and 9.7% monocots (Appendix 1).The species richness of medicinal plants in SMNP was higher than in Bale Mountains National Park [29], Mount Elgon, Kenya [31], Selale Mountain Ridges [27] and Gokand Valley, Pakistan [32], with 101, 107, 79 and 109 species, respectively.The higher numbers of medicinal plant species in SMNP might be associated with the mosaic pattern of microhabitats and great altitudinal variation (from below 2,000 m to over 4,500 m a.s.l.) that caused great ecological variation.In addition, the good number of therapeutic plants mentioned in the study area is another way of proving the rich traditional wisdom still practiced in the local community for their health care.Local communities adhere to the ancestral medical traditions by upholding them as a highly valued heritage of society [23].
Asteraceae was the most therapeutic plant speciesrich family (10%), followed by Solanaceae (7%), Euphorbiaceae (7%), Lamiaceae (6%) and Cucurbitaceae (4%).There were seven families represented by three species, six families were represented by two species, and the remaining 38 families were represented by one species.The aforementioned eighteen families accounted for about 64% of all species.Euphorbia was a species-rich genus (4 species), followed by Ficus, Remex, and Solanum, represented by three species each.Three genera (Alium, Echinops, and Helichrysum) were represented by two species each, and all other genera (89) were represented by one species each (Fig. 7, Appendix 1).The dominance of Asteraceae was also reported in [23] (12 species), [33] (19 species), [34] (25 species) and [32] (six species).Its dominance may be explained by species abundance, which is linked with their efficient dispersal mechanisms at higher altitudes in high mountains.The wide application of species from these families might also be associated with the presence of effective bioactive chemicals against ailments.
In terms of plant growth habit, 36 families, 47 genera and fifty-three species were herbs; twenty families, 26 genera and 28 species were shrubs; 15 families, 18 genera and 22 species were trees; nine families, nine genera and none species were lianas (Table 3).Therefore, most of the therapeutic species recorded were herbs (47%), followed by shrubs (25%) (Fig. 8).The dominance of herbs was also disclosed by [29] (54.46%), [34] (47%) and [32] (52.29%).Their abundance might be due to their abundance at higher altitudes since vegetation stature decreases as altitude increases, which ultimately leads to a higher abundance of herbaceous species with different growth forms (forbs, grasses, giant herbs, etc.).In addition, the ease of availability in the nearby area and the efficacy of herbs made local people depend more on herbs [33].Conversely, the findings of this work were contradictory to some other previous works [35,36], who reported shrubs were the dominant medicinal species due to their yearround harvest and their relative tolerance to any form of disturbance.The therapeutic plants collected in the study area were reported to treat 87 different aliments, of which 73% were known to treat human ailments only (Fig. 9).Similar results were reported in previous works [35,37].This demonstrates that greater emphasis is given to treating human health problems as compared to livestock [35]  Among the recorded medicinal plants in SMNP, thirteen (11%) of them were endemic to Ethiopia.These were Cynoglossum coeruleum subsp.coeruleum.Verbascum stelurum, Echinops kebericho, Inula confertifora, Lobelia rhynchopetalum, Urtica simensis, Aloe steudneri, Helichrysum horridum, Vernonia rueppellii, Thymus schimperi, Kniphofia foliosa, Kalanchoe petitiana, and Impatiens tinctoria.From these endemic plants, Urtica simensis, Aloe steudneri, Helichrysum horridum, Vernonia rueppellii, Thymus schimperi, Kniphofia foliosa, Kalanchoe petitiana, and Impatiens tinctoria were included in the IUCN (International Union for Conservation of Nature) Red Lists [38].Kalanchoe petitiana and Echinops kebericho were also reported by local people as locally threatened species in the area (Table 6).Being unique to Ethiopia, further analysis of their potential medical benefits could provide novel and significant scientific findings.

Sources of medicinal plants
The major source of medicinal plant species was the wild natural vegetation (77%).Some therapeutic plants were collected both in wild and cultivated areas (9.7%) and homesteads (8.8%) as well as few of the plants, such as Zingiber officinale, Citrus aurantiifolia, and Coffea arabica, were found in markets (4.4%) (Fig. 10).The result of this work agreed with similar previous works [24,36,39].This implies that natural vegetation still contains a good number of therapeutic plants, or that local communities do have little practice of conserving medicinal plants in their homesteads.Thus, a good opportunity for the inhabitant's bordering SMNP to access medicinal plants from the park might make the natural vegetation the main source of medicinal plants.

Plant parts used in the study area
Roots were the most widely used plant part (37%), followed by leaves (31%).Other plant parts that were utilized to prepare remedies made about 0.3-7.9% of the total (Fig. 11).The dominance of roots for remedy preparation was also reported by other similar previous studies [29,31].The local people perceived that roots are available in all seasons and that active biological ingredients are  more common at the tips of roots and leaves.A similar result was also disclosed by [40], who reported that the presence of more antibiotic chemicals in roots than other plant parts makes roots the most preferred.Conversely, most previous studies, including [34,35], reported that leaves are the most commonly used plant part for remedy preparation since, unlike roots, harvesting leaves does not have detrimental effects on the survival of medicinal plants.In addition, secondary metabolites are largely produced and concentrated in leaves.

Conditions of remedy preparation, preparation methods and administration routs
Most of the remedies were prepared from fresh plant parts (66.6%), whereas 17.5% and 15.9% were prepared from dry and fresh/dry forms, respectively.The result was consistent with the findings of the previous studies [28,41,42], who reported that the use of fresh forms increases the efficacy of medicinal plants since the secondary metabolites that have antimicrobial activities are retained in the extract since the chemicals are easily removed when they dry up.The remedies were commonly prepared by pounding (50.1%).Other preparation methods were far less common than pounding, which accounted for 13.2% of boiling (heating) to 0.6% of decoction (Fig. 12).This result is consistent with similar previous works [23,43,44].The reason pounding is most frequently employed is the assumption that pounding releases the therapeutic ingredients into the extracts through heavy, repeated striking of medicinal plants during the procedure.
The most frequently used route of remedy administration was oral (48.1%),where the remedies are taken by drinking or eating, followed by dermal, where remedies are creamed, rubbed, or bathed (34.7%).Other routs of were far less frequent than oral and dermal, which accounted for 9.5% of nasal and 0.3% of nasal/ dermal cases (Fig. 13).Similar reports have been made by [35,36,42].Oral rout is preferred due to the rapid reaction of the medicine to treat the illness that the local healers realized through their longer experience [36].

Efficacy of medicinal plants
The highest ICF value (84%) had been shown for categories of respiratory disease and febrile illness.On the other hand, the category of central nervous system (CNS)related diseases had the lowest ICF value (57%).The highest plant use citation was also found for the same disease category (Table 4).The highest ICF values demonstrated greater agreement among respondents' on the use of therapeutic plant species reported for treating respiratory disease and febrile illness.The observed highest informants' agreement, coupled with high plant use citations for the disease category, could also confirm the relatively higher incidence of the diseases in SMNP.According to [45], when information is exchanged between informants, ICF approaches to one demonstrating higher information exchanges between the communities living around SMNP.

Priority ranking of therapeutic plants
The preference ranking exercise was used to identify the most preferred medicinal plants from the list of plants that stop bleeding in the study.Thus, the ranking score disclosed that Rumex nepalensis stood first, showing the most preferred species for treating bleeding, followed by Achyranthes aspera (Table 5).On the other hand, Ficus palmata was seen to score the least preference value relative to other species to stop bleeding.Other therapeutic plant species listed in the priority ranking (Malva verticillata, Plantago lanceolata, Rumex nervosus, Aloe steudneri, and Datura  stramonium) had medicinal value in between the first and least ranked therapeutic plant species to stop bleeding.This finding disagrees with the finding of [24], who reported that Achyranthes aspera was the most preferred plant to stop bleeding.On the other hand, the fact that Achyranthes aspera has been mentioned as a medicinal plant in other study area may indicate that the species possesses medicinal properties that have been used to halt bleeding as well as the dissemination (or exchange) of indigenous knowledge among communities across different geographical areas.

Use diversity of medicinal plants
A direct matrix ranking exercise was used to test the use diversity of multipurpose therapeutic plants in the study area.This was also used as a means to identify which of the multipurpose plant species is under severe anthropogenic pressure with the corresponding threatening factor.Accordingly, Olea europaea was the most desired multipurpose plant species, followed by Hagenia abyssinica, whereas Brucea antidysenterica was the least wanted multipurpose plant species.In other words, Olea europaea and Hagenia abyssinica, the most desired multipurpose therapeutic plant species, become endangered due to overharvesting (Table 6).
The result could tell us these plants are exploited for several household purposes.Overharvesting of multipurpose medicinal plant species for medicinal use, agricultural tools and firewood purposes was the major factor in the decline of the species in SMNP.Previous authors [23,29,46] also disclosed that overharvesting of multipurpose medicinal plants for different purposes fastens the depletion of plant species in different regions of Ethiopia.According to [23], a plant's use diversity indicates how frequently it is used, which contributes to its decline in the area.These authors, based on the results of their work, called for urgent complementary conservation action (in-situ and ex-situ) to save the fast-eroding multipurpose medicinal plant species.

Fidelity level (FL)
It helps to measure the extent of faithful and consistent relative healing potential of each species treating a particular disease.In SMNP, the highest fidelity level was  recorded for Rumex nepalensis (92%) for treating wound, followed by Phytolacca dodecandra (90%) for treating rabies (Table 7).A higher fidelity level is considered as a clue for the high healing potential of these plants against the corresponding diseases.Secondary metabolites with wound healing effects were previously reported from Rumex nepalensis by [47,48].This might be the reason why local people use the species widely to treat wounds.Medicinal plants with the highest fidelity level indicate that they are widely used by the local people [20].In the study conducted by [36], Phytolacca dodecandra was found to have the highest fidelity level for treating rabies.The use of the same plant species for the same ailment in different localities demonstrates their cosmopolitan distribution and the fact that such plant species are effective for treatment of specific ailments.On the other hand, Echinops kebericho was seen scoring the lowest FL value (46%) for treating the evil eye (Table 7).The highest fidelity value indicated the most faithfulness of species to treat a given aliment and vice versa [3].Plants with the highest ranking value, ICF and/or fidelity level could be candidates for further phytochemical investigation to prove the bioactive components responsible for their high healing potential [23].

Marketability of medicinal plants
Local market surveys revealed that some therapeutic plants, Rubia cordifolia and Securidaca longepedunculata, were sold in the market for the treatment of cough and evil eye, respectively.While in the remaining local markets, plants were sold for other purposes such as food (Lycopersicum esculentum, Allium sativum, Allium cepa), fumigants for a pleasant smell at home (Cymbopogon citrates, Silene macrosolen, Olea europea subsp cuspidata, Otostegia integrifolia), tooth brushes (Olinia rochetiana, olea europea subsp cuspidata), and additives to fermented beverages (Tella) (Rhamnus prinoides) and spice (Ruta chalepensis) The less marketability of medicinal plants was also reported by [30].Most of the time, healers prescribe medication to patients at their home rather than bringing medicinal plants into the market with the intention of making money.Though most of the medicinal plants are not found in the market for the medicinal purposes, it was observed that they are marketable for other purpose.The marketability of medicinal plants, for any purpose, is closely associated to the conservation risk of the plant species.Market demand for medicinal plants (either for medicinal or others uses) can put pressure on wild populations that may lead to overharvesting and unsustainable collection practices that pose a conservation risk.The marketability of medicinal plants can also drive illegal trade by targeting species of high commercial value.In response to market demand, unsustainable harvesting practices may be employed, such as collecting plants at an immature stage or removing the entire plant instead of selectively harvesting specific parts.These practices hinder regeneration, disrupt ecological interactions and affect the long-term survival of the species.Promoting sustainable cultivation and domestication of medicinal plants can help reduce the reliance on wild collection and alleviate the conservation risk associated with high market demand.

Jaccard's coefficient of similarity
Jaccard's similarity coefficient was performed to compare the therapeutic plant species composition similarity with seven other previously studied areas in the nation.It has been found that the SMNP shared the highest similarity (34.53%) with Yilmana Densa and Quarit Districts, followed by Ada'a District (31.72%).This similarity might be due to shared common culture and religion.Though SMNP and Bale Mountains National Park are similar ecosystems, they share a lesser therapeutic plant species  8).This may be due to the altitudinal range differences between the two areas (Table 8).
The elevation ranges of Erer Valley in Babile lie between 940 and 1585 m, while SMNP lies between the ranges of 1500 and 4500 m above sea level.Variations and similarities in cultural practices and environmental factors, as well as the proximity of regions, are the causes behind the level of exchange of traditional knowledge and medicinal plants across various locales.

Threats and conservation of medicinal plants in the study area
Associated with the rapid population growth, the demand for agricultural and grazing land is increasing.Consequently, the vegetation of the study area is shrinking, followed by a decline in the availability of therapeutic plants over time.A preference ranking of six factors that threaten medicinal plants showed overgrazing as the most serious threat, followed by agricultural expansion.Therapeutic plant collection was ranked as the least threatening factor (Table 9).After the relocation of villages (Gich and Arkwazeye) from the park and removing the road out of the park boundary, overgrazing and agricultural expansion are identified as the major factors threatening the biodiversity of the park (SMNP Office report, 2020).This finding is in line with the study conducted in Gozamin district [29].On the other hand, the studies conducted in other areas of the nation [49][50][51] reported agricultural expansions as the principal threatening factor.Further analysis showed that Echinops kebericho was found to be the most threatened and rare therapeutic plant species, followed by Kalanchoe petitiana (Table 10).Similarly, the same species is reported as rare in the Sheka Zone [52].Frequent use of its root as traditional medicine might be the reason for its current rare occurrence.Regarding conservation practices, 89% of informants said that local communities exert little effort and do have   a weak tradition of conserving therapeutic plant species.Few members of the community attempt to grow plants on their homesteads for therapeutic purposes.Similar findings were also reported in Ankober district [23].The reason not to attempt growing in their homesteads might be related to the fact that they still have an opportunity to collect therapeutic plants in the park.

Novel ethnobotanical findings
New Vernonia rueppellii fresh leaves were reported to stop bleeding.Even this species was not mentioned in the globally reviewed 109 medicinal species of the genus Vernonia [53].Aloe steudneri (endemic to Ethiopia) was also the first to be reported for the treatment of human wound.These include bleeding, wounds and snake bites.
In addition, it is used to make hair black and smooth.Moreover, it was reported to make cattle and sheep more muscular.This might be related to the clearing of intestinal parasites, as [54] reported.Even though Dodonea angustifolia was reported for the treatment of different ailments by different authors, it is the first to be mentioned against Corona Virus Disease 19 .This study is also the first to report Kosteletzkya begoniifolia against abortion and scorpion bite.But it was reported for the treatment of anthrax [55] and body swelling [55,56].Even though Haplocarpha schimperi was reported for different medicinal values [23,34,57], the current study recorded leaves for the treatment of Tinea versicolor, which is the first report in Ethiopia.Lobelia rhynchopetalum and Satureja simensis are also mentioned only in this study against epidemic diseases and baby weight loss, respectively.The root of Carduus schimperi and the bark of Ficus vasta are also used for the treatment of sheep nasal discharge and female infertility, respectively, which is the first documentation in Ethiopia.
The specific medicinal use(s), either in single or in combination, of Helichrysum horridum, Inula confertiflora, Lobelia rhynchopetalum, Sesamum indicum, Aloe steudneri, Satureja simensis, Carduus schimperi, Haplocarpha schimperi and Kosteletzkya begoniifolia described in this work are also novel or findings reported for the first time in Africa.These medicinal plants are all endemic to Ethiopia.

Conclusion
The higher therapeutic plant species richness of the study area demonstrates that SMNP is serving as an in-situ conservation site and refuge for many endemic and endangered species.In other words, the documentation of a higher number of therapeutic plants proves the rich traditional lore of the local community in using therapeutic plants for their health care is still continuing.Increased demand for free grazing and agricultural expansion highly threatens the vegetation of the study area in general and therapeutic plants in particular.Erosion of therapeutic plants, verbal transfer via family line, great secrecy and lack of interest of the young generation in acquiring the traditional lore of therapeutic plants led to the deterioration of the long tradition of using therapeutic plants for health care.Practitioners should be encouraged (through various means) to share and bring their traditional wisdom to the scientific frontage, and highly preferred and endangered therapeutic plant species like Echinops kebericho should get priority for conservation measures, and local healers need to grow such plants in their homesteads.

Fig. 1
Fig. 1 Location map of SMNP with the adjoining districts

Fig. 2
Fig. 2 Different land forms of Simien Mountains

Fig. 3 Fig. 4 Fig. 5
Fig. 3 Climate diagrams for SMNP a for Debark and b for Chenek station

Fig. 6
Fig. 6 Ways of indigenous knowledge transfer

Fig. 7
Fig. 7 Families of medicinal plants in the study area

Table
Location and demographic profile of the participants Key (NB): Occupation (Lt represents the interviewee who have completed primary school and has religious education & Illiterate, Il); House hold, HH; Age category (Young

Study kebele Altitude Longitude Altitude Ecology No of HH Gender Age Occupation Religion
Information on Gender, age, occupation & religion pertains to informants .

Table 3
Classification of medicinal plants Fig. 8 Growth habit of medicinal plants

Table 4
Informant consensus factor by categories of diseases in SMNP

Table 5
Preference ranking values of eight medicinal plants used to stop bleeding

Table 6
Average direct matrix ranking scores of eight key informants for seven species Key: Med = medicinal, FD = firewood, Con = construction, Forg = forage, Agr tool = agricultural tool

Table 7
Fidelity level of the medicinal plant species used to treat the most common ailments This may be the result of differences in the people's historical and cultural traditions.The study conducted in the Erer Valley of Babile Districts shared the least number of common therapeutic plant species (3.77%) with SMNP (Table

Table 8
Jaccard's coefficient of similarity (Js) between the current study and other similar studies conducted in Ethiopia

Table 9
Presence ranking of threatening factors to TMPs

Table 10
Priority ranking of selected TMPs based on their degree of scarcity in the wild insights were revealed by a comparative analysis of the present work and earlier ethnobotanical research conducted in Ethiopia.It was reported for the first time that Helichrysum horridum (endemic to Ethiopia), Helichrysum citrispinum, and Vernonia rueppellii had traditional therapeutic values.Pounded roots of Helichrysum horridum and leaves of Inula confertiflora with butter were reported to treat cattle eye disease.Likewise, its dried and pounded root, together with the seeds of Lobelia rhynchopetalum and Sesamum indicum, was recorded to treat uterine myoma.In addition, tying its internal stem bark around a child's waist is used to avoid child bed waiting.Eating the crushed roots of Helichrysum citrispinum was reported for the treatment of a disease locally called "MICH" (a fetal disease caused by sitting on warm, moist soil or by exposing to suffocated material during sunny time).