Threat Assessment and Prioritization of High-Value Medicinal Plants In Pindari Valley, Nanda Devi Biosphere Reserve, India

The communication assesses the high-value medicinal plants reported in Pindari Valley, Nanda Devi Biosphere Reserve, Uttarakhand, using a score-based method for prioritization and conservation. A total of 42 high-value medicinal plants were assessed, prioritized and scored on the basis of rapid threat assessment. Maximum threat was recorded for Aconitum heterophyllum followed by Picrorhiza kurrooa and Nardostachys jatamansi given their limited number of individuals observed in the study area as well as high utilization patterns. Minimum threat status was recorded for Epilobium angustifolium, where the species was found in higher density in its natural habitat. Among the recorded species, 64% were observed growing in grassland/alpine pastures and open/alpine slopes. 55% of species were native/endemic to Himalaya and 48% were extracted by the inhabitants. Underground portions (roots/rhizomes/tubers) of 40% of the species were utilized leading to destruction in natural habitat. Out of 42 medicinal plants, 16 species have been prioritized for conservation and recognized in different threat categories and most of these species are collected from natural habitat without scientific knowledge. Conclusion of the study might helpful for identifying threatened plants in the region so as to initiate sustainable use and conservation practices of high-value medicinal plant resources. CONTACT Dhani Arya dhaniarya@gmail.com Department of Botany, Soban Singh Jeena University-Almora, 263 601, Uttarakhand, India. © 2021 The Author(s). Published by Enviro Research Publishers. This is an Open Access article licensed under a Creative Commons license: Attribution 4.0 International (CC-BY). Doi: http://dx.doi.org/10.12944/CWE.16.1.24 Article History Received: 17 July 2020 Accepted: 22 February 2021


Introduction
The mighty Himalaya contains a plentitude of medicinal plants and its habitants possess the knowledge of traditional medicinal plants. Indian Himalaya region (IHR) harbors about 1748 (23.4% of India) plant species recognized for their medicinal values. The higher diversity of medicinal plants in IHR is represented by the occurrence of a variety of native (31%), endemic (15.5%) and threatened elements (14% of total Red Data Book plants of IHR). 1 The need of medicinal plants is continuously increasing at local and global levels. Due to the high demand of medicinal plants in the Himalayan region, about 90% are collected from the wild 2 and around 70% are unscientifically harvested/ extracted from wild which enhances the loss on medicinal plant diversity. 2,3 Ever increasing demand of medicinal plants along with the habitat destruction, the world is experiences the principal challenge of minimizing loss of biodiversity 4,5 by conservation efforts. Further, few conservationists have tried prioritization of conservation efforts 6,7 due to higher number of extinction rate. 8,9 Number of medicinal plant species is now described under different threat categories 10 and in the immediate future, many species may warrant the declaration of a threatened status until adequate scientific data are available. 11 Therefore, the key challenge in the sustainability of medicinal plants is to synthesize the data on availability of medicinal plants and prioritization of certain species that require immediate conservation action. 12,13,14,15 A number of studies have been conducted on the utilization of medicinal plants in the IHR, viz, Dhar et al., 3 Bisht et al., 14 Kala 16,17 Gaur, 18 Maikhuri et al., 19 Chandra Sekar and Srivastava, 20 Chandra Sekar and Rawat, 21 Negi et al., 22 Bisht et al., 23 Joshi and Chandra Sekar 24 Joshi et al., 25 . However, the Pindari region is not having the data-set on diversity of medicinal plants, utilization and conservation efforts. In view of above, we studied the diversity of medicinal plants in Pindari Valley, a buffer zone region of Nanda Devi Biosphere Reserve, Uttarakhand.

Objectives of The Study
Keeping all the above in mind and the high use value and conservation importance of medicinal plants, the present attempt has been made to: (i) prepare an inventory of locally occurring medicinal plants through primary survey and secondary literature sources; (ii) identify and score the threatened and high-value medicinal plants (THMPs) based on their ecological (habitat, nativity, endemism and threat status) and socioeconomic values (plant part used, use value, user group and extraction trend); (iii) Prioritize the threatened high-value medicinal plants; (iv) suggest sustainable utilization and conservation strategies for the THMPs.

Materials and Methods Study Area
Pindari Valley (a buffer zone of Nanda Devi Biosphere Reserve) is situated in the Bageshwar district of Uttarakhand, Western Himalaya ( Figure 1). The total area of the Park is 339.39 km 2 at latitude 30°15' N and longitude 79°13' to 80°02' E. It lies between the Nanda Devi and Nandakot peaks and the presence of glacier extends from 3600 to 5000 m. The Pindar Valley is named after the Pindar river which emerges from the Pindari Glacier. The valley remains completely covered with snow for six months (early October to March). The entire valley has been considered for documentation of medicinal plant diversity. People traditionally collecting the medicinal plants from the valley resurveyed for recording the presence of medicinal plants. Further, the similar habitats nearby the traditional collection area were also surveyed for getting additional information on availability.

Questionnaire Survey/ Interviews
A semi-structured questionnaire survey was conducted in two villages namely, Jaitoli and Khati of Pindari Valley in the years 2016-2018 ( Figure 1). A total of 42 informants were selected randomly from 32 households for obtaining the utilization patterns. Further, the informants and Vaidyas (Medicine men) were also accompanied in the field for correct identification of particular plants, apart from house-hold interview. The complete information on medicinal plants, i.e., parts used and their habitat were collected. The information further cross checked with elderly people / Vaidyas repeatedly for confirming the utilization patterns.

An Approach for Rapid Threat Assessment (Rta) and Prioritization
For threat assessment, a list of Threatened and Highvalue Medicinal Plants (THMPs) was developed and rapid threat assessment (RTA) was carried out using Rapid Vulnerability Assessment method followed by Cunningham,26 and has been employed successfully by Shrestha and Shrestha 27 and Pandey et al., 28 . We followed an analytical method to prioritize the species of THMPs based on globally standardized criteria. To assess each species, we have used a total of seven ecological & socioeconomic criteria (i.e., habitat, plant part used, use value, user group, extraction trend, nativity, endemism and threat status). An appropriate numerical score ranging from 1 to 4 was assigned to each of these criteria (1 for low and 4 for high threat). 13,26,29 The prioritized species were based on the sum of the scores assigned to each of these criteria (Table 1) as explained in Box 1.

Box 1. Criteria Used and their Detailed Explanation Habitat
Habitat of the species was assessed on the basis of field observation during the field surveys and species were scored for the above mentioned four categories. Habitats like gravel, rocky and stony slopes are very fragile, species in these habitats were considered vulnerable to even the slightest human intervention and therefore scored at 4 (high threat). While, species in grasslands, alpine pastures and open/alpine slopes were ranked least vulnerable (score 1) as they have a large habitat range.

Plant Part Used
The plant part used means the part or parts of a specific species used for the treatment of diseases. The part of the plant used can influence the sustainability of a medicinal plant species and lead to a decrease in their population. 13 For example, species having whole plant, root and/or rhizome with medicinal properties were prone to be more vulnerable while leaf bearing species as an essential part of the preparation of medicine were prone to be less vulnerable. Thus, plant part used was also scored ( Table 1).

Use Value
The use value of a species related to the number of diseases for the treatment of which a specific medicinal plant species is being used. The use value defines the relative importance of the species in treating various diseases. 30 A higher use value for a specific species was pointed to a higher collection pressure in natural areas of that plant species and therefore a higher degree of threat. Here, the medicinal uses were categorized into four classes and a different score was given to each class (Table 1).

User Group
Data on user groups of different medicinal plants were evaluated through interviews with local people/ harvesters, traders, District Forest Officers and local authorities of Pindari Valley. These groups and their scores are tabulated in Table 1.

Extraction Trend
The extraction trend information was taken by interviewing the local people and Vaidyas of the study area. These scores are listed in Table 1.

Nativity and Endemism
Nativity and Endemism was assessed with the help of regional flora such as Flora of British India 31 ; Flora of the District Garhwal 18 ; Flora of Gangotri National Park. 32 Various specialized online databases such as e-flora of China (www.efloras.org/browse. aspx?flora_id=2), e-flora of Pakistan (www.efloras. org/browse.aspx?flora_id=5), and Tropicos (www. tropicos.org) were consulted. During the present study, the threatened medicinal plant species were classified into four categories on the basis of the geographic scale. Consequently, different scores were assigned to each species (Table 1).

Threat status
For the threat status, the criteria were based on the available threat status of species in the Conservation Assessment and Management Plan (CAMP), 33 the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), 34 International Union for Conservation of Nature (IUCN), 35 Red Data Book (RDB), 36 and other available literature.  Extraction trend (a)-Commercial + self 4 (b)-Commercial 2 (c)-Self-use (d)-No use 6.
Threat status (a)-Status in 3 categories or more

Fig. 2: Medicinal plants of Pindari Valley
The threat assessment reported that 64% of the HMPs of Pindari Valley grow in grasslands/ alpine pastures, open/alpine slopes while 55% HMPs are native/endemic to Himalaya (Figure 3). In present study area, 48% of these HMPs are harvested by local people (Figure 3). For the preparation of medicines, different parts of HMPs are used (i.e., roots, rhizomes, inflorescences, leaves, bulbs, fruits and tubers) (  (Figure 3).

Prioritisation of THMPs
Based on seven selected categories of Rapid Threat Assessment (RTA), such as habitat, plant used, use value, user group, extraction trend, nativity/ endemism, threat status, a total of 16 plant species were identified and placed in three categories on the basis of their cumulative score (Figure 4).  As per the present threat categorization, Aconitum heterophyllum is the most threatened species which is falling under threat category I. It is one of the most preferred species of the region, possess high medicinal use 39,45 as well as trade value. 49 Thus, the harvesting pressure is predominant threat factors for the species of category I. Further, the species under threat category II having higher scores were Picrorhiza kurrooa, Nardostachys jatamansi, Dactylorhiza hatagirea, Angelica glauca, and Sinopodophyllum hexandrum. All these species are preferred not only by residents of the Pindari Valley but also in other parts of Himalayas. 24,25 Although some of these species are prohibited for collection, besides of this local people are totally dependent on these medicinal plants due to lack of the healthcare facility in the higher altitude region. All these five species under category II are extracted for their underground parts and are sometimes harvested without leaving any remains of whole plant due to unavailability of scientific knowledge, which prevents further regeneration. 21 Hence, the species of category II mainly suffer from unscientific harvesting for frequently utilization by locals.
In third category (category III) recorded by Arnebia benthamii, Fritillaria roylei, Aconitum violaceum, Meconopsis aculeata, Trillium govanianum, Thymus linearis and Rheum australe are identified as a least threatened species in the study area, in view of less demand in market as well as local level.
The results of this study could direct the local government and stakeholders in determining which species should be targeted at conservation. Nearly two-thirds of the existing priority species in this part of the world have not been evaluated in compliance with IUCN guidelines and therefore deserve urgent conservation assessment. 50,51,52 Further, awareness on medicinal plants and conservation education to the local people needs to be provided for better understanding and sustainable utilization of these high-value medicinal plants.

Conclusion
The study revealed a total of 42 high-value medicinal plant species based on rapid threat assessment. Outcomes of the study suggested: (i) Aconitum heterophyllum with the highest score indicates that this species confronts the highest degree of threat among all the species. (ii) the study concluded that the demand of species, like Aconitum heterophyllum, Angelica glauca, Dactylorhiza hatagirea, Nardostachys jatamansi, Sinopodophyllum hexandrum and Paris polyphylla were high for various therapeutic purpose as well as trade value and needs major prioritization and conservation attention. (iii) providing awareness is an important tool for conservation as proper awareness among the local people is highly required. The threatened species can be promoted through cultivation in local village area for house-hold utilization may also reduce some pressure from wild. Further, the advance scientific techniques by using biotechnology can also be substituted for mass propagation and plantation in natural habitat for conservation. This study is an initial attempt to identify the endangered plant species, as also to draw the attention of conservation biologists, policy makers and researchers to implement conservation measures for these highly valuable plants.