Papageorgiou et al. Journal of Ethnobiology and Ethnomedicine (2020) 16:36 https://doi.org/10.1186/s13002-020-00390-4 RESEARCH Open Access Local knowledge about sustainable harvesting and availability of wild medicinal plant species in Lemnos island, Greece Dimitrios Papageorgiou1, Penelope J. Bebeli2, Maria Panitsa3 and Christoph Schunko1* Abstract Background: In Europe and the Mediterranean, over-exploitation and destructive harvesting techniques have been identified as two critical threats affecting the sustainable harvesting of wild medicinal plant (WMP) species. However, unsustainable harvesting is not an issue everywhere and localized assessments are needed. Local knowledge has been praised for its potential for local short-term assessments. In this study, we aimed to register the known, harvested, and locally utilized WMP species and understand local knowledge of harvesters about the ecological sustainability of WMP harvesting and the perceived changes of WMP availability. Materials and methods: This study was conducted on Lemnos island, Greece, in July and August 2018. Sixteen harvesters knowledgeable about gathering and using WMP were chosen through purposeful and snowball sampling. Successive free-lists provided insights on the taxa known, harvested, and utilized by harvesters and subsequent semi-structured interviews served to understand harvesting practices and perceived changes of WMP availability. Participant observation during seven harvesting walks allowed for additional insights and facilitated the collection of voucher specimens. Results: In total, 144 different plant taxa were listed as useful and 81 had been harvested in the prior 4 years. Medicinal applications were mainly related to digestive and respiratory system issues. A number of favorable harvesting practices suggested a high potential towards an ecologically sustainable harvest. Although, a decreased availability for certain plant taxa and harvesting sites was reported and mainly attributed to external factors such as pollution, unusually dry weather, intentional pastureland burning or chemicals in agriculture, but also destructive harvesting by less knowledgeable harvesters. (Continued on next page) * Correspondence: [email protected] 1Department of Sustainable Agricultural Systems, University of Natural Resources and Life Sciences Vienna (BOKU), Gregor-Mendel-Straße 33, 1180 Vienna, Austria Full list of author information is available at the end of the article © The Author(s). 2020 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Papageorgiou et al. Journal of Ethnobiology and Ethnomedicine (2020) 16:36 Page 2 of 23 (Continued from previous page) Conclusions: Knowledgeable harvesters of Lemnos gather and use a considerable number of WMP taxa and possess local knowledge that supports an ecologically sustainable harvest. However, certain plant taxa and areas of the island were indicated to be under pressure from harvesting, unusual climatic conditions, and agricultural practices. Our approach confirmed that local knowledge should be taken into account for assessing the sustainability of WMP harvesting. Keywords: Ethnobotany, Ethnopharmacology, Folk medicine, Foraging, Near east, Plant conservation, Traditional medicine, Wild plant gathering Background groundwork for developing scientific monitoring for In Europe and the Mediterranean, over-exploitation and conservation [11]. destructive harvesting techniques have been identified as In this study, we built on these insights and make use two critical threats directly or indirectly affecting medi- of local knowledge for assessing the sustainability of har- cinal plant species [1, 2]. The main direct environmental vesting activities. We aimed to (a) register the known, consequence of unsustainable harvesting practices is the harvested, and locally utilized wild medicinal plant reduced reproduction, growth, and survival rates of the (WMP) species, (b) understand the local knowledge of targeted species [3]. Such changes can consecutively de- harvesters about an ecologically sustainable WMP har- struct the ecosystem balances and influence the dynam- vesting, and (c) understand perceived changes of har- ics and structure of populations or even drive species to vesters of WMP availability. We thereby regard local the brink of extinction [2–4]. knowledge as epistemologically distinct from scientific However, unsustainable harvesting is not an issue knowledge and being valuable on its own rather than everywhere [5] and, in contrary to that, most plant spe- searching for its validation with scientific methods [15]. cies have been found to be harvested sustainably [6]. Tolerance to the harvesting of wild plants varies and de- pends on several factors, including a plants’ lifespan, the Methods part of the plant that is harvested, species abundance, Study area — the habitat where it is harvested, or species growth rate. The study was conducted on Lemnos island in contem- porary sources also spelled Limnos—Greece, occupying For example, slow-growing plants are particularly sus- 2 ceptible to heavy harvesting, while those of weedy nature about 482 km and biogeographically belonging to the are less vulnerable [7, 8]. The assessment of ecological North Aegean Sea [16, 17] (Fig. 1). It resides in the Pre- ′– ′ ′– ′ sustainability of harvesting thus needs to be based on fecture of Lesvos (39° 46 40° 02 N, 25° 02 25° 26 E) the consideration of several factors together, most im- [16, 18] and the climate of the area is the Mediterranean portantly the plant parts collected and its life form [9]. with mild winters, dry hot summers, and mean annual Estimating the sustainability of a harvested population precipitation of about 500 mm [19, 20]. and the effect of wild plant harvesting on other elements From an ecological perspective, the island is character- of the ecosystem requires long-lasting studies and can ized by a variety of habitat types including flat coastlines, be hard to isolate and monitor. lagoons, wetlands, marshes, sand dunes, remnants of a Local people however many times rely on local know- Valonia oak (Quercus ithaburensis Decne. subsp. macro- ledge to effectively and sustainably manage the harvest lepis (Kotschy) Hedge & Yalt.) forest, agricultural crops, of wild plants [10–12]. Consequently, the involvement of and extended phrygana [16, 18]. Despite its diverse envi- local people in natural resource and harvesting monitor- ronments, the flora of the island is rather poor com- ing regimes is considered key for its success [13, 14]. For pared to neighboring islands, with regard to the number short-term studies, research into the local knowledge of plant species, but still maintains significant ecological about the sustainability of wild plant harvesting may be value due to its multifarious vegetation formations [17]. a promising approach to understand the sustainability of Despite its high ecological and cultural value land- ’ harvesting activities. For example, this includes the har- scapes, the island s natural ecosystems have been greatly vesting techniques and management practices, not only degraded [18, 21]. The smooth topography with medium the specific methods used by the harvesters prior, dur- inclinations allowed intense human activities to take ing, or after harvesting, but also observations of plant place on almost the entire island. Extended agriculture, populations and harvesting activities of other harvesters. tourism facilities, and the traditional agropastoral prac- It may also act as a tool in detecting early signs of tice of burning and intense grazing (sheep and goats) changes in species and population trends and create the have drastically affected the formation of natural ecosys- tems and their vegetative composition [18]. Papageorgiou et al. Journal of Ethnobiology and Ethnomedicine (2020) 16:36 Page 3 of 23 Fig. 1 Map and location of Lemnos island. Village names indicate places where interviews and/or harvesting walks were conducted (figure adapted from [17, 18]) Nationwide restrictions for gathering WMP species new information coming out from the last five inter- apply in Lemnos. Current Greek legislation allows the views and no more knowledgeable WMP harvesters extraction of two kilos of fresh plant material per plant could be identified. Respondents’ ages varied from 32 to species and person. Uprooting, underground plant part 78 years, with an arithmetic mean of 57 years. Fifteen of removal, and orchid harvesting are completely forbidden the respondents were permanent residents