Field survey and data collection

In September 2019 and September 2021, our ethnobotany fieldwork was conducted in Gyirong. First, field study permission was obtained from the local community committee and government authority. We explained our purpose to local governments and requested assistance from them. All our fieldwork was conducted with informed consent. The snowball sampling method was used to select the key informants. Other informants were selected by the randomized household interview method. In addition, we attempted to train Daman guides to conduct ethnobotanical semi-structured interviews. In total, traditional knowledge was collected from 32 Daman (Table 1). The data on Tibetan ethnicity is cited from a previous ethnobotanical survey [23]. It is important to emphasize that we trained two young Daman people to conduct the fieldwork with us. The proportion of Daman informants in the study is 15% of the entire Daman population, while the Tibetan informants account for 5% of the local Tibetan population. Based on our fieldwork experience, the number of reported knowledge by the informants increases as the number of informants increases, but when the number of informants reaches a certain level, the amount of new knowledge reported no longer increases. Therefore, the selection of Daman and Tibetan informants is based on this principle, which ensures that the knowledge obtained can represent a certain group. In the selection of informants, this study strives to ensure a distribution of informants of both genders and different age groups (Table 1).

Characteristics of informants

Ethnobotanical knowledge was collected by semistructured face to face interviews. Because many Tibetans in the study area cannot speak Mandarin fluently, the field work was performed with the assistance of local guides who were employed with the help of local community leaders. All interviews were conducted in the Tibetan language, which was translated into Mandarin by local guides. All field studies were conducted with the consent of informants. The use reports of each informant for the plants were recorded. According to the commonly used 5W + 1H (What, Where, When, Who, Why, How) principle in ethnobotany, this study designed the following questions for semistructured interviews:

The questions were designed to collect data on the (1) vernacular name of the plants, (2) category of use, (3) parts used, (4) methods for preparation and administration, (5) characteristics of the plant material (dried or fresh) and (6) collection time.

The specimens were collected from the field of survey with the help of the key informants and all materials are labelled with numbers and names. Photographs of each plant were taken. All specimens were kept in the herbarium of Kunming Institute of Botany (KUN). The Flora of China was used as a reference to identify the plants [30] and The Plants of the World Online was used to ensure the Latin name of the plants [31].