Local knowledge about sustainable harvesting and availability of wild medicinal plant species in Lemnos island, Greece

Papageorgiou et al. Journal of Ethnobiology and Ethnomedicine https://doi.org/10.1186/s13002-020-00390-4 (2020) 16:36 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: 1 Department 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 In Europe and the Mediterranean, over-exploitation and destructive harvesting techniques have been identified as two critical threats directly or indirectly affecting medicinal plant species [1, 2]. The main direct environmental consequence of unsustainable harvesting practices is the reduced reproduction, growth, and survival rates of the targeted species [3]. Such changes can consecutively destruct the ecosystem balances and influence the dynamics and structure of populations or even drive species to the brink of extinction [2–4]. However, unsustainable harvesting is not an issue everywhere [5] and, in contrary to that, most plant species have been found to be harvested sustainably [6]. Tolerance to the harvesting of wild plants varies and depends on several factors, including a plants’ lifespan, the part of the plant that is harvested, species abundance, the habitat where it is harvested, or species growth rate. For example, slow-growing plants are particularly susceptible to heavy harvesting, while those of weedy nature are less vulnerable [7, 8]. The assessment of ecological sustainability of harvesting thus needs to be based on the consideration of several factors together, most importantly the plant parts collected and its life form [9]. Estimating the sustainability of a harvested population and the effect of wild plant harvesting on other elements of the ecosystem requires long-lasting studies and can be hard to isolate and monitor. Local people however many times rely on local knowledge to effectively and sustainably manage the harvest of wild plants [10–12]. Consequently, the involvement of local people in natural resource and harvesting monitoring regimes is considered key for its success [13, 14]. For short-term studies, research into the local knowledge about the sustainability of wild plant harvesting may be a promising approach to understand the sustainability of harvesting activities. For example, this includes the harvesting techniques and management practices, not only the specific methods used by the harvesters prior, during, or after harvesting, but also observations of plant populations and harvesting activities of other harvesters. It may also act as a tool in detecting early signs of changes in species and population trends and create the groundwork for developing scientific monitoring for conservation [11]. In this study, we built on these insights and make use of local knowledge for assessing the sustainability of harvesting activities. We aimed to (a) register the known, harvested, and locally utilized wild medicinal plant (WMP) species, (b) understand the local knowledge of harvesters about an ecologically sustainable WMP h (...truncated)