Nature Conservation 51: 189-225 (2023) See ee alae 6 \\ N ature doi: 10.3897/nat tion.5 1.96255 RESEARCH ARTICLE j . oi natureconservation re Conse ation https:/ / natureconservation. pen soft. net Launched to accelerate biodiversity conservation Local perception of the current state and threat factors of a critically endangered species, Celtis toka (Forssk.) Hepper & J.R.I. Wood, in Burkina Faso: implications for species conservation Zainabou Dabré'”, Issouf Zerbo??, Blandine Marie Ivette Nacoulma?, Dodiomon Soro!, Adjima Thiombiano* | West African Science Service Centre on Climate Change and Adapted Land Use (WASCAL), Graduate Research Program on Climate Change and Biodiversity, UFR Biosciences, University Félix Houphouét Boigny, B.P. 165, Abidjan 31, Cote d'Ivoire, Ouagadougou, Burkina Faso 2 Laboratory of Plant Biology and Ecology, University Joseph Ki-Zerbo, 03 B.P 7021, Ouagadougou 03, Burkina Faso 3 University Center of Tenkodogo, University Thomas Sankara, 12 B.P 417, Ouagadougou 12, Burkina Faso Corresponding author: Zainabou Dabré (zainaboudabre@gmail.com) Academic editor: G. Akomolafe | Received 13 October 2022 | Accepted 22 February 2023 | Published 15 March 2023 https://zoobank.org/D 1 LAF5F2-5F32-420E-8489-073BF7FA6951 Citation: Dabré Z, Zerbo I, Nacoulma BMI, Soro D, Thiombiano A (2023) Local perception of the current state and threat factors of a critically endangered species, Celtis toka (Forssk.) Hepper & J.R.I. Wood, in Burkina Faso: implications for species conservation. Nature Conservation 51: 189-225. https://doi.org/10.3897/natureconservation.5 1.96255 Abstract Celtis toka, the only species of the genus Ce/tis (family Cannabaceae) encountered in the flora of Burkina Faso, is critically endangered in the country. To engage the public for the future conservation and domesti- cation of the species, knowledge of the factors threatening Celtis toka survival is necessary. Thus, the study objective was to identify the perceptions of local people concerning the current state and conservation strategies of Ce/tis toka in Burkina Faso. To investigate potential solutions to the threats posed to Celtis toka, we randomly surveyed 405 consenting participants using a selected semi-structured interview. Moreover, field observations were per- formed to assess the threat drivers cited by local people of the Sudanian and Sudano-Sahelian climatic zones. Descriptive analyses (relative frequency and fidelity level) and generalized linear models (GLMs) were used to highlight the impact of sociodemographic factors and climate zones on the current state, threat drivers, and potential solutions. The chi-square test was used to assess whether to plant C. toka. GLM analyses revealed that local knowledge about the current state, threat factors and potential solution to the threat as related to natural stand varied significantly according to ethnolinguistic group (P < 0.000), sex (P = 0.01) and age (P = 0.01). Rural people had varying perceptions of the current state Copyright Zainabou Dabré et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. 190 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) of C. toka. Sixty-eight percent reported a decrease in population, ten percent reported scarcity, and five percent reported extinction. The views of local people were that the factors affecting C. toka were pruning (25%), climate change (14%), deforestation (10%), ageing (10%), debarking (9%), and agriculture (7%). Potential solutions included planting (45%), conservation of C. toka and its habitat (27%), sustainable use of Celtis toka (14%), promotion of education and awareness about Celtis toka (10%) and tree/crop association (5%). The study concluded that the ethnobotanical knowledge of Ce/tis toka may play an important role in its conservation and domestication in Burkina Faso. Furthermore, its incorporation into reforestation and restoration programs is critical to species survival. Keywords climate, conservation strategies, COVID-19, decline, ethnobotany, extinction, West Africa Introduction Climate change is defined as a change in the weather pattern of a location or region that is related to average weather components such as temperature, wind patterns and precipitation (Ifeanyiobi et al. 2012). For instance, extreme weather events devas- tate the land and terrestrial ecosystems and exacerbate food insecurity for humanity. These changes, according to the United Nations’ Intergovernmental Panel on Climate Change, have a large impact on many people who are thought to be disproportionately vulnerable to the effects of climate change (IPPC 2021). To cope with global change and mitigate its consequences, rural communities rely on forests, primarily in terms of multipurpose plants for medicine, food, fodder, shade, renewable energy, windbreaks, erosion control, carbon sinks, soil improvement, fertility restoration and conservation (Ifeanyiobi et al. 2012). Ethnobotany, a branch of ethnobiology (Houéhanou et al. 2016), is the study of the relationships between plants and culture as well as the local perception of the use, management (Bridges and Lau 2006; de Albuquerque and Hanazaki 2009) and the state of plant resources. Moreover, ethnobotanical knowledge is critical for species conservation, mainly for endangered species that have been recognized by the Conven- tion on Biological Diversity in Rio de Janeiro (CBD 1992). Furthermore, promoting endangered plants is critical to ensuring their sustainable conservation, domestication, and inclusion in reforestation and restoration programs. Therefore, plant promotion, conservation, domestication, and introduction through restoration and reforestation, necessitate a scientific approach based on local perceptions of the current state, threats, and potential solutions. Celtis toka (Forssk.) Hepper & J.R.I. Wood belongs to the Cannabaceae family. The genus Celtis includes approximately 60—70 species worldwide (Mahre et al. 2017) and 12 species in Africa (Sattarian and Van Der Maesen 2005). This species is a very large tree with a compact crown (Sattarian 2006) and is usually monoecious (Alfaifi et al. 2021). It reaches 25 m in height and 2.2 m in diameter at breast height. The bole is either short or tall with ramifications (Dabré et al. unpublished). Celtis toka (C. toka) is Local perception of the current state and threat factors... eal an open gallery forest, dense dry forest, savannah, sacred grove, and rocky area species (Neumann 1992; Shepherd 1992; Rabeil 2003; Akoegninou et al. 2006; Savadogo and Thiombiano 2010; Hohn and Neumann 2016; Arbonnier 2019). It thrives in areas with low rainfall (110-960 mm yr."') and high temperatures (26-30 °C) (Watrin et al. 2007). It is widely distributed and found throughout Benin, Burkina Faso, Cen- tral African Republic, Chad, Céte d'Ivoire, Eritrea, Ethiopia, Gambia, Ghana, Guinea (Conakry), Mali, Mauritania, Niger, Nigeria, Senegal, South Sudan, Sudan, Togo, Uganda, and Yemen (Sattarian 2006; IUCN 2019). The species provides a variety of products used for food (leaves, fruit); medicine (leaves, barks, roots, flowers, seeds); construction (wood); firewood and charcoal for human cooking activities; and fodder (leaves) for animals and handicrafts (Blench 2000; Lykke et al. 2004; Teklehaymanot and Giday 2010; Seignobos 2014; Hohn and Neumann 2016; Piqué et al. 2016; Arbonnier 2019; Badiane et al. 2019). The fruits and leaves are considered edible in Sudan (Arkell 1947), Ghana (Irvine 1961), Senegal (Lericollais 1990), Nigeria (Kiee et al. 2000; Harris and Mohammed 2003; Kubmarawa et al. 2011), Cameroon (Nakagawa 2008; Neba 2009; Betti and Yemefa 2011), Benin (Djégo-Djossou et al. 2015) and Burkina Faso (Dabré et al. unpub- lished). Mballow et al. (2020) stated that C. toka is the most commonly used species by communities in west and east Africa. Moreover, tannins, glycosides, alkaloids, sapo- nins, phenols, coumarins, flavonoids, mucilage, triterpenoids and steroids are phyto- chemicals extracted from leaves of C. toka (Fall et al. 2017; Abba Idris and Halima Mohammed 2020). In addition, all organs of C. toka are used to cure diseases such as measles, chicken- pox, malaria, back and eye aches, ringworm, fever sore, mycosis, headache, and mental diseases (Hahn-hadjali and Thiombiano 2000; Betti et al. 2011; Arbonnier 2019; Dia- tta et al. 2019). The roots, leaves and bark are used in Nigerian traditional medicine to treat various diseases, including epilepsy (Muazu and Kaita 2008). Additionally, the plant organs are used to treat trypanosomiasis (Osue et al. 2018). In Cameroon, the bark is also used to cure epilepsy (Isabang et al. 2016). The medicinal use of C. toka was also highlighted by Bizimana et al. (2006) in Mali and Badiane et al. (2019) in Senegal. In Burkina Faso, leaves, bark, flowers, fruits, grains, and roots were used to heal 29 ailments, such as madness, yellow fever, eye ache, malaria, casting, vitamin deficiency, ringworm, diarrhea, backache, toothache, ulcer, measles, and chickenpox (Dabré et al. unpublished). In Ethiopia, C. toka is a wild tree that provides an important economic service because it is preferred for the hanging of beehives (Bareke 2018), for timber, and for making local boats (Rolkier and Abebe 2015). In addition, C. toka has a mystical value in Burkina Faso (Savadogo and Thiombiano 2010). Cultural and mystical values were also highlighted by Dabré et al. (unpublished). The International Union for Conservation of Nature (IUCN)’s forest work ad- dresses the role of trees and forests in building resilience to climate change (IUCN 2021). Additionally, the IUCN sustainable use initiative has been successful in deliver- ing conservation outcomes that benefit society (IUCN 2020). C. toka was assessed on 192 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) the IUCN Red List of Threatened Species in 2023 as being of Least Concern (LC), and its current population trend is stable at present (IUCN 2019, accessed on January 25, 2023). According to the IUCN (2019), C. toka has a very broad distribution and a large population, with no major threats currently existing and no significant future threats being identified. Even though C. toka is classified as LC at the global level (IUCN 2019), this spe- cies is either threatened, rare, critically engendered and even extinct in some temper- ate regions and the Sahelian region in Africa (Hahn-hadjali and Thiombiano 2000; Garzuglia 2006; Al-Khulaidi 2018; Alfaifi et al. 2021; Tchobsala et al. 2022). None- theless, the species seems to be lacking in Senegal, Guinea Sudan, and Uganda (Hau- man 1942). Moreover, C. toka is threatened in Benin, northern Cameroon and the Sa- helian region of Africa (Gonzalez et al. 2012; Dansi et al. 2013; Moksia et al. 2019). In Chad, the species is either extinct or endangered (Tchobsala et al. 2022). Although the species is important in Yemen, it is currently rare and must be evaluated and monitored regularly (Al-Khulaidi 2018). In Saudi Arabia, C. toka is thus a very rare and threat- ened species (Alfaifi et al. 2021). The reasons for the rarity and near local extinction of this species in some parts of Africa are understandable. This is because of the enormous dependency on this species and its products for ecological and economic purposes in some parts of African countries. This, leads to overexploitation, thus predisposing the species to a high risk of local extinction in Africa. This phenomenon is prevalent in west Africa, especially Burkina Faso, where the species is subject to overexploitation because of its medicinal, fodder, food, and mystical uses (Dabré et al. unpublished). Only C. toka, one of the twelve species of the genus Ce/tis in Africa, is found in Burkina Faso, and it is on the verge of extinction. Several pieces of empirical evidence suggest that C’ zoka is rare, threatened, critically endangered or extinct in Burkina Faso. Authors have shown that in Burkina Faso, C. toka is a one-of-a-kind critically endangered species (Garzuglia 2006) and is threatened to the point of one day disap- pearing (Hahn-hadjali and Thiombiano 2000; Thiombiano et al. 2010; Bayala et al. 2011). Vodouhe et al. (2007) also stated that C. toka has been on the verge of extinc- tion in Burkina Faso since 2007. For instance, Hahn-hadjali and Thiombiano (2000) also stated that since 2000, C. toka has disappeared in eastern Burkina Faso, except in sacred groves. Furthermore, Bayala et al. (2011) discovered that C. toka was the most threatened species in the agroforestry parkland of Burkina Faso. Additionally, Savadogo and Thiombiano (2010) specified that the wild plant C. toka is endangered in the Northern and Southern Sudanian zones of Burkina Faso. More recently, the studies of Savadogo et al. (2017) have shown that C’ toka is rare in the communities of the strict Sahelian, southern and northern Sahelian regions of Burkina Faso. ‘There- fore, given the socio-economic and ecological importance of C. toka to the teeming African populace, and given its potential high risk of local extinction in Africa, there is a need for its conservation. However, an effective conservation strategy of the natural resources must take into account the knowledge and opinions of the stakeholders, es- pecially the local people who are the direct beneficiaries of the resources so conserved Local perception of the current state and threat factors... 193 (Amoutchi et al. 2021). These authors argued that indigenous people all over the world have preserved distinctive understandings, rooted in cultural experience, that guide relationships among human and non-human beings in specific ecosystems. ‘Thus, their perception and knowledge of threats to any natural resources, and their subsequent contribution to designing a conservation action will produce a positive outcome. The local people (especially in Burkina Faso) depend directly on the services provided by C. toka for their livelihoods. Therefore, they are expected to be the most affected if the species becomes extinct, and also, they are expected to be well aware of the nature of the disturbances and threats the species is facing given their indigenous knowledge of it. Their perception of the threats (the impact and causes) and knowledge of anthro- pogenic activities impacting this species, being part of their indigenous knowledge, are essential for making and implementing decisions and policies related to the mitigation of these threats, and the management of this species in the ecosystem. Furthermore, the knowledge and perception of the local people represent the baseline information for motivating and directing any research projects regarding any conservation action targeted at this species. Despite its socioeconomic and cultural importance and its role in mysticism, knowledge of the threat factors of C. toka in Africa in general and Burkina Faso, in particular, is lacking. In this regard, this study aimed to assess the diverse local knowl- edge and perceptions of the dynamics and threats to C. toka in west Africa (using Burkina Faso as a case study), with the view to recommending conservation strategies to mitigate the local extinction of this species in west Africa where the species is already reported to be critically endangered. Specifically, we seek to answer the following ques- tions: (a) What are the perceptions of rural people regarding the status of C. toka in Burkina Faso? (b) What are the threats to the survival of C. toka in Burkina Faso? And (c) what are the perceptions of the local population concerning the potential solutions to the threats posed to C. toka in Burkina Faso? We explicitly tested three hypotheses: H1: Interviewees perceived the extinction of C. toka in the study sites. H2: Anthropogenic activity is the main driver of species decline. H3: Planting and the conservation of the species and its habitat are two of the most important solutions to the threats posed to the species. Description of the study site This study was conducted from November 2020 to January 2022 in villages near Kou, Dinderésso, Sourou, Sa and Koulbi classified forests located in the Sudanian and Suda- no-Sahelian climatic zones of Burkina Faso (Fig. 1). In both climatic zones (BCZ), the climate is tropical with two separate seasons: rainy and dry periods. ‘The principal rivers are Kou and Mouhoun, and the main soils are leptosols, vertisols, ferralsols, luvisols, 194 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) sro" YA 40'0" Wl te ae Oe | so" Wi ooo" l "O'0"E 2° O'O"E Legend NM BR Cities ————" Burkina Faso A * GD studied Pas Zz Climatic Zones i Africa : | Sahelian [=| Sudanian [ | Sudano-Sahelian, . [_] Attica > Doshinon Sourou a Dédougou Benin ES Dabré 7. Jan 2023 rLI-L —s 1 \ 0.3060 120 180 } Source, BNDT 2012 soow 400"W 300"°W 2OO"W LlO'O"w aro'o" 1°0'0"E 2°0'0"E Ivory Coast Figure |. Localization of the study sites in Burkina Faso. (Studied PAs: studied protected areas). lithosols and hydromorphic soils (Savadogo and Thiombiano 2010). The vegetation types include various savannahs, dry forests, and gallery forests. The flora consists of some Sahelian, Sudanian and Guinean species, such as Vitex chrysocarpa Planch, Antiaris africana Engl., Parkia biglobosa (Jacq.) R.Br. ex G. Don, Lannea microcarpa Engl. & K. Krause, Dialium guineense Willd., Cola laurifolia Mast., Carapa procera DC., Vachellia seyal (Delile) PJ.H Hurter, Detarium microcarpum Guill. & Perr., Balanites aegyptiaca Del. (Nacoulma et al. 2018). The sociolinguistic groups are Dafing, Gourmantché, Gourounssi, Bobo, Bozo, Dioula, Sambla, Senoufo, Bam- bara, Marka and Bwaba. ‘The key livelihoods are traditional subsistence farming, prin- cipally of cereals (millet, sorghum, and maize), livestock breeding and trade. Materials and methods Materials Celtis toka is a wild plant that thrives in a variety of environments. It has different local names around Africa (Table 1). Local perception of the current state and threat factors... 195 Table |. Some local names of Celtis toka in Africa. Countries Dialect Benin Dendi Yoruba Burkina Faso Mooré Mooré Cameroon Arabe Fulfuldé Haoussa Toupouri Kanouri Mofu Mafa Fulfuldé Fulfuldé Mofou Arabe Ethiopia Anywaa Kara (people) Kwego (people) Nigeria Mali Senegal Wolof Diola Sereer South Sudan Mabanese Arabe South Kordofan Sudan Sudan Methods Vernacular names Séékossou Afoufé Bousamsambou Pargandé Silsaka Ngouso Aboum gatou Hala Djiho Douki Likan Loubour Ngouzo Sabak Shéshébé Wanka Ganki Wanko Mebed Falmaro Laero, Zuguay, Lompo Aape Kamaua, Gamya Mbul Busingilit ngan Shaw Tekey Mohagria Mohagria, Lipingo Sampling strategy and data collection Sources Dansi et al. 2013 Djégo-Djossou et al. 2015 Achigan-Dako et al. 2010 Thiombiano et al. 2012 Thiombiano et al. 2012 Betti and Yemefa 2011 Vivien 1990 Gilbert et al. 2019 Gilbert et al. 2019; Seignobos and Tourneux 2002 Gilbert et al. 2019 Betti et al. 2011 Awas 1997 Teklehaymanot and Giday 2010 Teklehaymanot and Giday 2010 Ogungbenro et al. 2018 Bizimana et al. 2006 Gonzalez 2001 Diatta et al. 2019 Lericollais 1990 Bloesch 2014 Bloesch 2014 Ismail and Elawad 2015 Hamid and Kordofani 2015 A preliminary assessment was carried out in November 2020 to obtain an overview of the availability and distribution of C. toka. Furthermore, this assessment allowed us to obtain approval from authorities and village leaders, as well as to fine-tune the ques- tionnaire. The preliminary assessment and survey were carried out while maintaining social distancing and other preventive measures (wearing a nose mask and using hand sanitizer) to avoid the spread of COVID-19. From the three climatic zones of Burkina Faso, two climatic zones (the Sudanian climatic zone (SCZ) and the Sudano-Sahelian climatic zone (SSCZ)) were chosen considering the accessibility of the areas and the occurrence of C. toka. A discussion was held with the administrators, environmental officers, forest officers, farmers, fishermen/women, hunters, traditional healers, and 196 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) | Legend ie Bobo HS Mossi HE Gwaha |S Marka [Samo [ED Peul-Rimaibe [| Gourmantsché HJ Sembla HY Gourounsi Hd Bisa [1 Senoufo (1) Africa SS Turka Niger Ivory Coast (Source : (GK 2002 Figure 2. Map of the ethnolinguistic groups questioned in the study areas. elders. Next, field observations were made cooperatively with field guides, farmers, vil- lage leaders and elders to look for C. toka availability, accessibility, distribution, threat drivers and potential solutions within the study sites. Thirty-four villages were includ- ed in the survey, comprising twenty-five ethnolinguistic groups (Fig. 2). The ethnolinguistic groups Bambara and Bozo represent immigrants from Mali. Villages were chosen based on the presence of the multipurpose species C. toka. Overall, 405 (148 female and 257 male) consenting local people who knew C. toka were randomly selected. Data were collected using a selected semistructured interview (Sop and Oldeland 2011; Theodory 2016) and direct field observation. It was impossible to interview an equal sex ratio in each village because the investigations were based on the knowledge of C. toka. All respondents were at least 30 years old because they were the only ones who knew about C. toka and its status. Data for age, sex, career, education level and ethnolinguistic group of the informants were recorded. Ethnolinguistic groups that were represented by few in- dividuals were classified as “other” for the purpose of performing the statistical analysis. Proficient local translators were used to translate French into the local languages. Photographs of the leaves (Fig. 3), the trunk (Fig. 4), and the fruits (Fig. 5) of C. toka were taken during the prospection, kept, and shown to each household in both climatic zones to ensure that local communities were familiar with C. toka (Arbonnier 2019). The respondents were questioned about the following: e current state of C. toka in their community, e factors affecting C. toka survival, ¢ potential solutions to the threat. Local perception of the current state and threat factors... LOZ Figure 3. Pictures of leaves used for quick identification by local people during the survey. Pictures: Z. Dabré, 2020. Figure 4. Pictures of the trunks used for quick identification by local people during the survey. Pictures: Z. Dabré, 2020. 198 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) Figure 5. Pictures of fruits used for quick identification by local people during the survey. Pictures: Z. Dabré, 2020. Data analysis Before the analyses, the interviewees were divided into two generations: adults (30-55 years) and older adults (= 55 years) (Sop et al. 2012). Three and four Sudanian and Sudano-Sahelian ethnolinguistic groups, respectively, were considered major ethnolin- guistic groups, with the remainder classified as “other” (Fig. 2, Table 3). The relative frequency and fidelity level (Table 2) were employed to analyse the most destructive threats to C. toka. GLMs with Poisson errors and chi-square tests at a threshold equal to 0.05 were used to detect sociodemographic parameter (ethnolinguistic groups, age, and sex) effects on the current state, threat, and potential solutions in the BCZ. Chi- square analysis was also used to determine whether to plant C. oka in the study areas. All statistical analyses were performed using R version 4.1.1 (R Core Team 2021). Results Sociodemographic characteristics and local perception of the status of C. toka in Burkina Faso Sociodemographic characteristics of local populations In total, 405 people were interviewed in this study, with 203 in the SCZ and 202 in SSCZ (Table 3). Most of the interviewees were male (72.77%), autochthonous (81.19%), and farmers (75.74%) with no formal education (80%). Bozo (8.37%) were immigrants, and those classified as “other” were autochthons (Table 3). Local perception of the current state and threat factors... 199 Table 2. Formulas related to relative frequency (RF) and fidelity level (FL). Index Computation Explanation R RF = (FC/SF) x 100 Frequency of citation (FC) quoted by a given Measures the ratio of the number of timesause 5%). R: References, A: (Thiombiano et al. 2016), B: (Friedman et al. 1986). Table 3. Sociodemographic characteristics of informants and study design. Demographic parameters Variables Sudanian Sudano-Sahelian Sex Female 40.95 27.23 Male 59.05 T2AE Total 100 100 Residential status Autochthon 65.02 81.19 Migrant 34.98 18.81 Total 100 100 Ages Adult (30-55) 46.80 58.91 Old (> 55). 53.20 41.09 Total 100 100 Ethnolinguistic groups Bobo 71.44 13.86 Bozo 8.37 = Bwaba - 31.68 Dafing - 23.27 Dioula 10.34 hi Mossi - 12.87 Others 9.85 12.87 Total 100 100 School level None 79.59 74.26 Primary 15.75 21.28 Secondary 4.37 3.47 University 0.29 0.99 Total 100 100 Main activity Farming 61.44 75.74 Trade 21.61 8.91 Breeding 11.65 11.39 Handwork 5.3 = Hunt - 3.96 Total 100 100 Local perception of the status of C. toka in Burkina Faso Overall, 68% of informants (77.94% in the SCZ and 58.28% in SSCZ) (Fig. 6) widely expressed that the multiuse species C. toka was greatly decreasing (SCZ: 41% < FL< 90% and SSCZ: 52 < FL < 96) (Table 4). Thirteen percent of the participants expressed that the species is stable. In SSCZ, approximately 19% and 11% of the interviewees con- firmed that the sacred tree C. toka was either rare or extinct, respectively. However, 4% of the local people (5.88% in the SCZ and 2.86% in SSCZ) highlighted that the spe- cies was increasing in abundance (Fig. 6, Table 4). As the most surveyed communities, 200 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) Extinct Rare Increasing Stable Current state of C. foka Decreasing 0 10 20 30 A0 50 60 70 80 Relative Frequency (“) Global view OSudano-Sahelian & Sudanian Figure 6. Local perception of the current state of the multiuse species C. toka in Burkina Faso. Bobo, Bozo, Dioula, Bwaba, Dafing, Mossi, and Dioula represent the ethnolinguistic groups that perceived the most recent status of C. toka in the study areas. Ethnobotani- cal knowledge of the state of C. toka varied greatly across ethnolinguistic groups. How- ever, Dioula (FL: 90%) and Bobo (FL: 62%), belonging to SCZ, perceived the decline of C. toka. However, in the SSCZ, Mossi (FL: 96%) and Dafing (FL: 81%) reported a decrease in the species. Respondents in the SCZ with an age above 55 years identified more of a declining status of the species than others. Regarding sex, men (SCZ) and women (SSCZ) reported more threatened status based on their traditional knowledge when compared to others. The rarity of the species was perceived by the Bwaba culture (FL: 42%), and extinction features of C. toka were mostly perceived by the Mossi (FL: 35%) and the “other” ethnolinguistic groups (FL: 35%) in the SSCZ (Table 4). The GLM analysis revealed that local knowledge of C. toka’s status varied greatly across ethnolinguistic groups in terms of extinction and stable status, across sexes for all status levels, and across ages for all status levels except decreasing status (p—val- ue < 0.05). Adults and elderly people in the BCZ had dissimilar perceptions of the declining, scarcity, and extinction aspects of C. toka (p-value < 0.05) (see Table 5). Local perception of the threat factors of C. toka in Burkina Faso According to the respondents, the sustainability of C. toka is threatened by some unfa- vourable factors, such as anthropogenic and natural factors. However, 4% of respond- ents indicated that there are no threats to the sustainability of C. toka. Globally, the threat features to C. toka were perceived as pruning (25%) for food and fodder, climate change (14%), deforestation (10%), ageing (10%), debarking (9%), agricultural ex- pansion (7%), bushfires (6%), and “other” (6%) (Fig. 7). The “other” category referred Local perception of the current state and threat factors... 201 Table 4. Local knowledge of C. toka in two climatic zones of Burkina Faso. Criteria / Variants Sudanian climatic zone Sudano-Sahelian climatic zone Patterns Bobo Bozo Dioula Others Bobo Bwaba_ Dafing Mossi Others (n=145) (n=17) (m=21) (n=20) = (n=28) (n=64) (n=47) (n=26) = (n=26) F FL F FL F FL FEF FL F FL FEF FL F FL F FL F_ FL (%) (%) (%) (%) (%) (%) (%) (%) (%) Current state of Extinct 0 0 0 0 0 0 0 0 tL gf 3° 205 92. <4 9, 35- *9F E35 C. toka Rare OF oe he foe Ay SS ie OF te 27 A ee SS ST iG 95 Decreasing 90 62 7 41 19 90 21 70 15 54 33 52 38 81 25 96 16 62 Stable 37 26 6 35 4 20 8 29 8 5 11 1 Increasing 10 7 1 6 6—0 5 3 11 0 4 0 0 O =F 139 - 15 - 21 = «27 = 29% 4 78 ~ 49 -~ 42. '2 32. + Threat factors Pruning 56 39 8 47 13 62 13 65 4 14 62 97 33 70 6 23 15 58 Bushfire 20 14 O 0 2 #10 1 5 1 2 3 7. 15s «0: 0 0 0 Ascing” Oh B45 D5 12) GIT 10: MT gS ro Ot 18S) Be est ee 2G Debarking 35 24 2 12 3 14°15 75 6 21 44 6 12 26 4 15 3 12 Climate 23 16 3 18 4 19 3 #15 2 7 20 31 #15 32 = 5 19 2 8 change Deforestation 19 13 1 #6 3 14 3 #15 2 #7 #15 23 5 #11 9 35 #7 27 Farming 7 5 2 12 5 24 3 #15 #1 4 17 27 4 9 10 38 7 27 Lack of 9 6 0 0 0 0 1 5 2, 7 x li 4 9 0 0 0 0 regeneration Settle of 8 6 0 0 1 5 3 15 O QO; AQ 19> 22 4 1 4 1 4 infrastructures Overgrazing 6 4 1 6 0 0 0 0 0 0 15 23 3 6 15g 4. ROR, we 0 Others 3 2 1 6 0 0 0 0 Booth], «5 8 2 4 0) 0 0 0 Failure of 4. 3 1 6 3 14 0 0 0 0 1 2-4 70: C. toka =F 211 - 21 «= 36 + 43 + 21 - 173 - 100 =- 44 = 42 - Potential Tree/crop 9 6 3 18 1 5 1 5 0 0 2 3 2 0 2 8 0 0 solutions to the _—_ association threats Planting 38 26 4 24 9 43 4 20 5 18 36 56 2 49 19 73 11 42 Conservation 47 32 3 18 I 5 0 O 5 18 8 33 28° 58-16 62 5 19 of C. toka and its habitat Sustainable use 22 15 3 18 1 5 0 “OO Spl a ally (4689p ez 8 1 4 of C. toka Promoting 13* 9 1 6 0 0 1 5 1 4 11 17 36 2 1 4 1 4 education, and awareness about C. toka =F 129 <9" H4 ot De 4 6 - 144 - 64 - 72 - 40 - 18 - n: number of individuals interviewed, F: frequency, FL: fidelity level, and =F: sum of frequencies. to the specific habitat of the species, infertility of soil, production of charcoal, diseases, attacks by parasites, fungi, epiphytes, termites, and invasion of Azadirachta indica and Ficus. In the SCZ, the main causes were pruning (21%), deforestation (13%), climate change (13%), debarking (12%), bushfire (9%), ageing (8%) and agriculture (8%) (Fig. 7). Pruning (FL:47%), climate change (FL:18%), debarking (FL:12%), and age- ing (FL:12%) were emphasized by the Bozo, and debarking (FL:75%) was emphasized by others in the SCZ (Table 4). In the SSCZ, pruning (28%) and climate change (15%) were reported as the key drivers (Fig. 7). Pruning (FL: 70%), climate change 202 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) Table 5. Impact of socio-demographical factors and climatic zones on the current state of C. toka through GLMs analyses. CZ: Climatic zones, n: number of individuals surveyed, S: Sudanian, SS: Sudano — Sahelian, and X?: chi-square. Figure 7. Threat factors by climate zone in Burkina Faso. F. of C. toka: failure of C. toka. Lack of regeneration Settle of infrastructures [ Threat factors Overgrazing Agriculture Deforestation Climate change F. of C. toka Others Bushfires Ageing Debarking Pruning OGlobal view OSudanian OSudano-Sahelian 10 15 20 Relative frequency (%) 25 30 CZ Variables n Extinct Rare Increasing Decreasing Stable Ethnolinguistic groups S Bobo 145 0+0 0.014 + 0.12 0.23 + 0.42 0.47 + 0.5 0.26 + 0.44 Bozo 17 0+0 0.035 + 0.22 0.47 + 2.75 0.92 + 5.63 0.48 + 3.08 Dioula 21 0+0 0.048 + 0.22 0.51 + 0.51 1+0.51 0.53 + 0.22 Others 20 0+0 0+0 0.3 + 0.47 0.45 + 0.51 0.25 + 0.44 SS Bobo 28 0.037 + 0.19 0.074 + 0.26 0.088 + 0.27 0.56 + 0.50 0.30 + 0.47 Bwaba 64 0.20 + 0.41 0.42 + 0.50 0.047 + 0.21 0.47 + 0.50 0.078 + 0.27 Dafing 47 0.043 + 0.20 0.043 + 0.20 0.064 + 0.25 0.79 + 0.41 0.11 + 0.31 Mossi 26 0.267 + 0.46 0.133 + 0.35 0.067 + 0.26 0.67 +0.49 1.333 + 0.35 Others 26 0.207 + 0.46 0.103 4 0.25 0.067 + 0.26 0.57 £0.39 1.303 + 0.32 x 7.83 2.1 1.15 2.98 6.08 P value 0.00468 0.138 0.295 0.0804 0.02 Sexes S Female 91 0+0 0.011 £0.11 0.269 + 0.44 0.314 + 0.47 0.337 + 0.47 Male 112 0+0 0.027 + 0.16 0.230 + 0.42 0.566 + 0.50 0.168 + 0.38 SS Female 55 0.15 + 0.36 0.1 + 0.30 0.025 £ 0.16 0.7 + 0.46 0.175 + 0.38 Male 147 0.123 + 0.33 0.254 + 0.44 0.078 + 0.27 0.561 + 0.50 0.114 + 0.32 xX? 23.406 39.03 15.41 4.67 10.64 P value 0.00028 < 0.0000 0.00022 0.0309 0.00169 Age S Old 108 0+0 0.020 + 0.14 0.215 + 041 0.479 + 0.50 0.243 + 0.43 Adult 95 0+0 0.017 + 0.13 0.322 + 0.47 0.406 + 0.50 0.237 + 0.43 SS Old 83 0.086 + 0.28 0.272 + 0.45 0.074 + 0.26 0.530 + 0.50 0.123 + 0.33 Adult 119 0.178 + 0.39 0.151 + 0.36 0.055 + 0.23 0.671 + 0.47 0.137 + 0.35 x 14.49 34.65 18.26 2.04 4.66 P value 0.00055 < 0.00000 < 0.000 0.153 0.03407 Local perception of the current state and threat factors... 203 (FL: 32%), ageing (FL: 28%) and debarking (FL: 26%) were reported at a heightened level by the Dafing culture in the SSCZ (Table 4). These disturbances affect the sur- vival of the critically endangered species C. toka. The results globally suggested that pruning, climate change, deforestation, age- ing, debarking, farming expansion and bushfires are the major factors that threaten the survival of C. toka in the study areas. Pruning, climate change, and deforestation ranked first, second and third, respectively, signifying that they are the most proximate threatening factors (Fig. 7). In the SCZ, ageing was perceived by Bobo culture; climate change by Bozo culture; debarking, pruning, farming and failure of C. toka by Dioula culture; and deforestation and settlement of infrastructures were mentioned by other ethnolinguistic groups as the main predictors of the decline of the species. However, in the SSCZ, deforestation, farming and pruning were the main causes of the extinction of C. toka identified by the Mossi. The Dafing culture believed that C. toka is threat- ened due to climate change and human activities (bushfires). According to the Bwaba culture, overgrazing and debarking are the key reasons for the threat in the study area (Table 6). In the BCZ, older people emphasized that the species has declined due to climate change, farming, ageing, deforestation, settlement of infrastructure, bushfires, failure of C. toka, pruning and other causes (Table 6). The overall threat factors of C. toka varied only across ethnolinguistic groups for ageing, pruning, climate change, farming, settlement of infrastructure, and lack of regeneration (p—value < 0.05). In addition, the threat drivers were statistically similar (p-value > 0.05) between both sexes and generations for identifying deforestation, settlement of infrastructures, lack of regeneration, failure of C. toka and bushfire as causes (Table 6). Based on our observations in the field, the threat factor in the BCZ could be natu- ral (hole, wind, drought, crown gall, fungi, and epiphyte) as well as anthropogenic. However, old C. toka trees contained very large hollows (Fig. 8) which weakens the species during wind (Fig. 9), or fire action (Fig. 10). In addition to the hole, C. toka has a fasciculate root (Fig. 11) which accentuates the effect of wind. Ficus thonningii Blume (Fig. 12), fungi (Fig. 13), and crown gall and holes (Fig. 14) infest C. toka tree species. In the study areas, some livelihoods result in the overharvesting of the leaves of this species either for food or fodder uses (Fig. 15), and the bark by traditional healers (Fig. 16). Furthermore, some individuals died, probably due to drought, ageing, or diseases (Fig. 17). According to our field observations, the assessment of the threat by climatic zones showed that the SCZ was more exposed than the SSCZ (even though C. toka is less abundant in the SSCZ) due to anthropogenic activities such as artisanal activities (Fig. 18), and industrial mining (Fig. 19),and bushfire (see Fig. 10 above). However, the exploitation of granite negatively affects seed germination and some- times sapling growth. Some local people often cut C. toka (Fig. 20) for charcoal, fire- wood, or farm settlement purposes. Epiphyte (Fig. 21), grazing by goats and cattle (Fig. 22), and biological invasion by Azadirachta indica A. Juss. (see Figs 11, 21, 22 above) of C. toka organs or sap- lings were noticed in some livelihoods of the study areas. Epiphytes (Fig. 21) infested C. toka trees to the point that they lost their leaves and remained apparently dead. 189-225 (2023) Zainabou Dabré et al. / Nature Conservation 51 204 ‘orenbs-1yp :,x pur ‘uelayes — ourpns :¢¢ ‘uRTURpNs :¢ ‘podaains syenprArpuT Jo Joquinu :u ‘souoz SNRUNT[D °7D L700 6670°0 189°0 SI70 IZ€0 L770 TLEO'0 669°0 8£6'0 €Z¢e0 S¥0'0 onyea 7 S97 IS'y L1‘0 IZT S60 VT (7 yI0 0 LL‘0 68°€ 7X LITO+FIOO PEOFLETO 6904 ZETO0 LITO+FFPIOO €70+4 6500 0€0 +9600 S704 8900 €FO+Z770 I€OFOITO 17046070 OF 047610 FEOF ZETO GIT JMPV 070+ 1900 SPYO+P8TO STI +7770 0+0 cEO+F IITO SEOF9ETO 77047900 9704 60€0 87049800 FEOF9ETO IF04 8710 SVO+P870 €8 PIO Ss cTO+ S00 OF 0+F TOTO STT+O0FEO0 C7O0+FS00 $70+48900 0€0+70TO0 GEOF6TO 87045800 CCOFISOO O€0F7COITO 770+ ISO OF O0+F TOTO $6 JPY slo0+ E00 LEO+FP9TO 8904 1ZT0 810+ F7E00 17048700 80049000 67046800 LZE0+FIZIT0 S7T0+8900 SEO+FPFIO O€0+4 E010 LE0+F9T'0 801 PIO S asy yOSTO 9S0E0 6S10°0 6910 6270 Z0Z00°0 y¥80'0 €01'0 6£1'0 8100 S6r'0 onyeAd: 9c I 8¢°0 COL (as €lT £99 6C EST TUT LUS y9'l ux 60°70 + 600°0 OF 0+ 1770 LIT +6170 600+ 6000 870+ 8800 9€04 6710 27046400 FHO+FPSTO ECLOFETIO OFOFE6GTO CEO+FP8TO CHOF8CTO ZHI TFN 0+0 ZE0 +6810 S€0 + $200 0+0 Z70 + SZ0'0 910+ S700 9T04S700 8FO0+FSE0 91045700 O€0FT0 €E€O0FS7IO 8E0FSZTO SS FeUy Ss 0+0 6£0+4+Z910 LOT+7S70 810+4S€00 97040200 070+ €F00 8E0+F7Z10 FEOFOETO O€0+FS600 G6EO0FE8TO SEOFE6ETO 9EOFLFI0 CIT FPN Z10 +0700 LE0+8ST0 FYOF8Z10 070+ F700 8104+ €€00 STO+ 7700 ITO +700 LEOFLITO STO+CCOO S7TO0+L900 STO+FCCOO SEOFFFIO 16 rewoy S SOXaG yOE'0 c1¥00'0 TOO 870 10°0 6670 66900°0 6L90'0 ZITO 000°0> 98600°0 ones 7 90°T SOL SIT LE0 968°0 vv 0 €O'L Le 6E°T LLI 1y9 ux 0+0 90 FTVTO 9650470 0+0 0+0 0+0 yCO+LETO 17049500 IV0+ZETO 97042970 SEO+FEETO IT SPIO 0+0 SV0+29T0 990470 0+0 0+0 0+0 TS0 +2970 S7T0+2900 SPO+L9T0 97042970 SEOFEETO 97 ISSO 070+ €70'O T€0+9010 671 +970 0+0 87'0 F $80°0 S70 F £900 9EOF8FI'O SFOFILTO OTOFEHOO I€O0F9OI0 870 FS800 LZKOFG6IEO Ly Buyeq 0+0 eyvO+veTO ITT +8810 €10+9T00 T€0+601'0 €FO+FPETO 8SITOFIECOO 8FO+F6SE0 G6GE0+F88I0 ECFOFPETO SHO0+S970 THOF6ITO 79 eqemg 0+0 67:0 + ZZ0°0 610 + 8€0°0 0+0 970 + TZ0°0 0+0 610 + 9€0°0 0+0 0+0 970+ 1ZL00 610+49€00 970FTZO0 8 9994 SS cT0+ 8700 8604+ 29¢0 L604 £0 0+0 0€"0 + $60°0 0+0 0€0 +6600 770+ 8700 OF 0+06T0 OFO+F061'0 OF 040610 9E0+F7FTO0 07 SP|IO 0+0 EST +18¢0 €ST+18€0 9¢€0 + €FI'0 0+0 0+0 €0+S600 0€0+46600 7@70+F8700 SE0+EFT0 FHO+8E70 OFO+0610 IZ PNOId 0+0 €VO0+ CTO €VYO+FCCTO 970 +9600 0+0 70 + 9S0'0 ce'0 + ITT0 0+0 yO +9500 CTEOFIITO €¥0+4 7770 LT 020g 57047900 LZ¥O0+67E0 FL04F0810 91048700 F704 7900 070+ 100 SEOFLETO 8E0+47CLTO €704S6S00 FEOFIETO C704 8700 FEOFITETO SPI 9904 S sdnoi3 orsmsurjouyyy vx04 “yy uoresJouaser sammjonseyur osueyo sIIT|O surunig Suppreqoq jo ommyreyg joxpey 8urzes31249 supsy jo apg uoneisssojoq = Surunse.y oeuny) u_ssgyquizeA 7D ‘Ose PULLING Ul YYZ *") OF SJeIIYA PIJIPISUOD STOIEF JA['TT) FO SiNsor pue (pas +) SonyeA UI] °*9 VIGeL Local perception of the current state and threat factors... 205 Figure 8. Risk factor: hollow in most of C. toka natural stands in the BZC. Pictures: Z. Dabré, 2020. 206 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) - an om Figure 10. Risk factor: ageing and fire effect on hollowed out C. toka in SCZ. Pictures: Z. Dabré, 2021. Figure I 1. Risk factor: ageing, action of the wind and Azadirachta indica A. Juss. invasion in SCZ. Pictures: Z. Dabré, 2021. Local perception of the current state and threat factors... 207 a wh Figure 13. Risk factor: attack of fungi on C. toka. Pictures: Z. Dabré, 2021. 208 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) wt ae iney Na Ey Figure 14. Risk factor: holes (yellow round), ageing, crown gall (red round) attacks coupled with debark- ing in the BCZ. Pictures: Z. Dabré, 2022. Figure 15. Risk factor: heavy pruning of C. toka’s leaves in BCZ. Pictures: Z. Dabré, 2021. Local perception of the current state and threat factors... 209 is Fe fal Figure 16. Risk factor: debarking for traditional medicinal purposes in the BCZ. Pictures: Z. Dabré, 2020. Major F: tts '§ Figure 17. Risk factor: natural death due either to drought, diseases, or ageing of the hollowed out C. toka in the BCZ. Pictures: Z. Dabré, 2022. 210 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) Figure 19. Risk factor: industrial mining in the habitat of C. toka in the SCZ. Pictures: Z. Dabré, 2021. Traditional potential solutions to the threat The conservation strategies proposed by the locals included the conservation of C. toka and its habitat, the sustainable use of C. toka, and the promotion of education and awareness about C. toka. However, planting was the most important solution expressed by all ethnolinguistic groups, as confirmed by the high FL (SCZ: 43%, SSCZ: 73%) Local perception of the current state and threat factors... 211 Figure 21. Risk factor: ageing, epiphytic attack (red circles), holes, crown gall (yellow circles), and Azadirachta indica A. Juss. invasion in SSCZ. Pictures: Z. Dabré, 2022. 212 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) Figure 22. Risk factor: ageing, rotting, Azadirachta indica A. Juss. invasion and animal grazing in the SSCZ. Pictures: Z. Dabré, 2022. value in the BCZ (Table 3). Planting (45%), conservation of C. toka and its habitat (27%), sustainable use of C. toka (14%), promoting education and awareness about C. toka (10%), and tree/crop association (5%) were the future potential solutions pro- posed to solve the threat posed to C. toka in the study areas. Moreover, potential solu- tions in the SCZ were planting (34%), conservation of C. toka and its habitat (33%) to protect it from human pressures such as cutting, fire, animal grazing and sustainable use of the species (16%) by avoiding overharvesting (pruning, debarking, and overusing the roots). In the SSCZ, planting (58%), conservation (19%), and sustainable use (10%) were the key solutions proposed to address the threats posed to the species (Fig. 23). In the Sudanian climatic zone, conservation, sustainable use of the species, and planting were cited by the Bobo, Bozo, and Dioula cultures, respectively, as poten- tial solutions to the threats posed to the species. According to the Sudano-Sahelian climatic zone, the conservation of the species and its habitat was mostly perceived by the Dafing and planting by the Bwaba as key solutions to address the threat. Most of the solutions were proposed by males in the BCZ. In the SCZ, older people proposed more solutions than younger adults. A contradiction was found in the SSCZ (Table 8). Local perception of the current state and threat factors... 213 The chi-square test results of the different responses of informants who were in- volved in answering whether to plant C. toka show that there is a significant relation- ship among the respondents in the study sites (Table 7). The GLM analyses of respondents’ perceptions of potential solutions to the threat posed to C. toka revealed that local perception varied significantly according to ethno- linguistic groups, sex, and ages for the solution of planting and ethnolinguistic groups for the solution of conservation of C. toka and its habitat (p—value < 0.05, Table 8). However, no differences in promoting education and awareness about C. toka, associ- ating C. toka with crops, and sustainable use of the species were found among all the sociodemographic parameters (p—value > 0.05, Table 8). Discussion Local perception of the current state of the agroforest tree C. toka in Burkina Faso The spatial dynamics of C. toka declined in the study area. This could be explained by the fact that the species was once rare. For instance, Gonzalez et al. (2012) emphasized Potential solutions 0% 20% 40% 60% 80% 100% Relative Frequency @ Global view WSudanian MSudano-Sahelian Figure 23. Traditional potential solutions to the threat according to climatic zones in Burkina Faso. Table 7. Chi-square test showing whether to plant or not C. toka in Burkina Faso. Climatic zones % of respondents Chi-square Yes No DF x P value Sudanian 77.02 23.91 1 27.94 < 0.0001 Sudano-Sahelian 99.61 0.39 1 98.43 < 0.0001 DF: degree of freedom, X?: chi-square. pales Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) Table 8. Mean values (+ Std) and results of GLMs of potential solutions to the existence of C. toka in Burkina Faso. Variables n Planting Conservationof Promoting education, and Tree/crop Sustainable use of C. toka and its habitat awareness about C. toka association C. toka Ethnolinguistic groups S Bobo 145 0.262 + 0.44 0.152 + 0.36 0.090 + 0.29 0.062 + 0.24 0.014+ 0.11 Bozo 17. 0.235 + 0.44 0.118 + 0.33 0.059 + 0.24 0.176 + 0.39 0.059 + 0.24 Dioula 21 0.429+0.51 0.048 + 0.22 0+0 0.048 + 0.22 0+0 Others 20 0.2 + 0.41 0+0 0.05 + 0.22 0.05 + 0.22 0. 05 + 0.22 SS Bobo 28 0.179 £0.39 0.107 + 0.31 0.036 + 0.19 0+0 0+0 Bwaba 64 0.563 + 0.5 0.094 + 0.29 0.172 + 0.38 0.031 + 0.18 0.031 + 0.18 Dafing 47 0.489+0.51 0.064 + 0.25 0.021 + 0.15 OF0 0.021 + 0.15 Mossi 26 0.7 +£0.51 0+0 0.087 + 0.26 OFE0 0+0 Others 26 0.6+0.51 0+0 0.067 + 0.26 0+0 0+0 x? 19.55 15.56 1.41 4.21 0.48 P value < 0.000 < 0.00 0.244 0.051 0.477 Sexes S Female 91 0.189 + 0.39 0.111 + 0.31 0.033 + 0.18 0.044 + 0.21 0.033 + 0.18 Male 112 0.336 + 0.47 0.133 + 0.34 0.106 + 0.30 0.088 + 0.29 0.009 + 0.09 SS Female 55 0.5+0.51 0.1 = 0.30 0.15 + 0.36 0.025 + 0.16 0+0 Male 147 0.464 + 0.50 0.070 + 0.26 0.070 + 0.26 0.009 + 0.09 0.026 + 0.16 x’ 6.09 0.29 0.29 0.27 0.05 P value 0.013 0.596 0.587 0.613 0.831 Age S Old 108 0.285 + 0.45 0.118 + 0.32 0.056 + 0.23 0.063 + 0.24 0.021 + 0.14 Adult 95 0.24 + 0.43 0.136 + 0.35 0.119 + 0.33 0.087 + 0.28 0.017 + 0.13 SS Old 83 0.469 + 0.50 0.49 + 0.21 0.135 + 0.34 0.025 + 0.16 0.012 + 0.11 Adult 119 0.479 + 0.50 0.109 + 0.31 0.041 + 0.20 0+0 0.027 + 0.16 x? 5.53 1.31 0.2 2.24 0.01 P value 0.018 0.260 0.650 0.151 0.913 CZ: climatic zones, n: number of individuals surveyed, S: Sudanian, SS: Sudano — Sahelian, X*: chi-square. that the density of C. toka has declined in the Guinea ecological zone of the African Sahel due to the climate. Moreover, human action could be the reason for the decrease in C. toka in Burkina Faso. Most youths were unaware of the value of this species; therefore, they cut saplings as well as adult trees. In addition, to establish agricultural land, some residents cut down C. toka individuals. Moreover, habitat loss could be the factor responsible for the changes in the species’ population dynamics. However, the transformation of the species’ habitat (gallery forests) by market gardening or ex- otic plants could explain its decline. For instance, in the Sudanian climatic zone, the habitat of C. toka was converted into vegetable crops (such as tomatoes, cucumbers, strawberries, eggplants, sorrels, carrots, papaya and others) and exotic tree plantations (Mangifera indica L., Tectona grandis L.f., Anacardium occidentale L., Eucalyptus cama- ldulensis Dehnh., Annona muricata L., Annona squamosa L., Delonix regia (Boj.) Raf., Citrus lemon (L.) Burm.f.). Dansi et al. (2013) demonstrated that the threat posed to C. toka may be due to forest destruction, bushfires, destructive harvesting methods and a lack of knowledge about the species. In the Sudano-Sahelian zone, C. toka was reported to be rare and even extinct. This extinction could be due to a lack of regenera- tion to replace the ageing population of the species. Research has shown that the threat Local perception of the current state and threat factors... 215 posed to C. toka in northern Cameroon is due to the lack of regeneration. For instance, the regeneration was 0% in an unprotected area and 0.14% in protected areas (Moksia et al. 2019). According to the Mossi and other cultures from the SSCZ, the species was extinct due to overexploitation, the change in the environment and the failure of C. toka in the area. Hence, C. toka has extremely small population sizes and therefore is in extreme danger of extinction. For instance, it was difficult to obtain two or three in- dividuals in the same area, and most of them were old and isolated in their communi- ties. Additionally, the use of the species for traditional medicine may have contributed to its extinction in some study sites, mostly in the Sudano-Sahelian communal zone. Climate has a greater impact on the species abundance and distribution in the Sudano- Sahelian climatic zone than in the Sudanian climatic zone because C. toka is denser in the Sudanian than in the Sudano-Sahelian region. Deforestation caused by agricultural development, infrastructure installation, and climatic variability has an impact on the spatial dynamics of C. toka. Similar findings were reported by Hahn-hadjali and Thi- ombiano (2000); Garzuglia (2006); Vodouhe et al. (2007); Thiombiano et al. (2010); Bayala et al. (2011); Savadogo et al. (2017) in Burkina Faso. Moreover, C. toka is either extinct or endangered in Chad (Tchobsala et al. 2022), rare in Yemen (Al-Khulaidi 2018), and rare and threatened in Saudi Arabia (Alfaifi et al. 2021). Hence, different ethnolinguistic groups, sexes and generations have diverse views on the status of C: toka due to cultural differences. Traditional knowledge of the dy- namics of C. oka is influenced by ethnolinguistic groups over time. The scarcity and decline of C. toka have been perceived by most sociocultural groups. For instance, the declining factor of C. toka was perceived more strongly by the Bobo, Bozo, Di- oula Dafing, and Mossi cultures. ‘This is because those cultures are autochthonous and know the status of the species over time. Traditional healers (Bobo, Bwaba, Dioula, Mossi), hunters (Bwaba) and fishermen/women (Bozo) who interact with the habitat of C. toka have a better knowledge of the species’ status. Knowledge of the declining characteristics of C. toka within a hamlet is similar from one generation to another. This could be explained by the fact that both younger adults and the elderly were aware of the species’ status and thus noticed the decline and/or extinction of C. toka. Threat to the sustainability of the sacred tree C. toka in Burkina Faso Even though C: toka is a tree associated with mysticism, it faces diverse threats to its continued existence from various anthropogenic activities and natural factors. Extinc- tion and decline of C. toka are due to a range of factors, including overharvesting (pruning, debarking, and rooting), climate change, deforestation, ageing of the popu- lation, and farming expansion. According to rural residents, overexploitation is the most serious threat because, in conjunction with the scarcity of C. toka, organs were harvested in an anarchic way. These findings were similar to those of Moksia et al. (2019). Respondents were confident that roots, leaves, and bark are a critical part of C. toka; therefore, its overharvesting may affect its reproduction. Overharvesting of bark and leaves has been reported to have reduced fruit produc- tion in Burkina Faso (Nacoulma et al. 2017). Furthermore, heavy pruning could affect 216 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) tree development and photosynthesis (Suchocka et al. 2021). Three percent (3%) of the rural community thought C. toka was endangered due to a lack of regeneration. Regeneration could be influenced by either seed availability or seed quality. C. toka has been overpruned to the point where it no longer produces fruits in some areas. The lack of seeds may be the primary cause of the lack of regeneration. Gaoue et al. (2011) demonstrated that the overharvesting of fruits and seeds exposes natural stands vulnerable to population ageing due to the threat to natural regeneration. Overgrazing may also contribute to a lack of regeneration. Four percent (4%) of locals believed that the scarcity of species was caused by overgrazing of seedlings and saplings. Harvesting roots, bark, and even leaves may expose C. toka to diseases such as fungal pathogens, galls, epiphytes, termite attacks, and others. These pathogens could drive the species to extinction by interfering with C. toka reproduction, increasing competition for nutri- ents, and most likely causing mortality. However, Boussim et al. (2004) indicated that C. toka is parasitized by a pest called Tapinanthus globiferus (A.Rich.) Tiegh. However, Otry and Laflamme (2009) confirmed that various fungi are pathogens of specific tree species and cause tree mortality in vulnerable trees. Approximately 12% of the respondents stressed that climate change is one of the reasons for the extinction of the taboo species. They noticed that during the past 30 years, there have been drastic changes in the frequency and volume of precipitation patterns, rising temperature and wind. Sop and Oldeland (2011) stated that drought is one of the primary causes of vegetation change in the Sub-Sahel of Burkina Faso. However, strong winds in the savannah and rocky zones cause the ageing population of the species to easily be up- rooted because the species lacks a taproot, while drought causes the species to dry out. Furthermore, because the ideal temperature for C. toka is between 26 and 30 °C, an increase in temperature could inhibit regeneration (Watrin et al. 2007). According to respondents, floods have an impact on C. toka habitat by destroying habitat and up- rooting any C. toka found on the banks because some of them had their roots hanging in the rivers in some way. In addition, ageing (13%) leads to the death of C. toka. Thus, drought and pathogens can hasten this death. Franklin et al. (1987) demonstrated that tree death is a natural ecological process involving one or more pathogens and other microbes. However, the proportion of farming expansion (7%) and urbaniza- tion (4%) was less of a contribution to the extinction of the sacred tree C. toka. These factors are still a major challenge today because the human population is growing, and forests are being destroyed to make way for infrastructure and farmlands. According to locals, previously, the C. toka tree was not widespread (1%) in different villages of Burkina Faso, and it was not accessible even for local food, fodder, firewood, and medi- cal purposes. Most of the fishermen, hunters and traditional healers had to travel to other villages to look for the organs of C. toka. According to the respondents, fire (6%) may impact the seeds, seedlings, saplings and even the age population of the species. However, bushfires could reduce the abundance of seedlings by killing seedlings and decreasing the seed bank of C. toka in the soil. Furthermore, bushfires may influence the trunk and hollows of adult individuals, which could potentially lead to the death of the species. Fire triggers plant mortality throughout the crown, stem and root (Miller Local perception of the current state and threat factors... IAF, and Findley 2014). The severity and impacts, at the regional and global scales, of the burned area resulting from wildfires, have increased in recent decades (Doerr and San- tin 2016). Wildfires have an impact on soil properties (Agbeshie et al. 2022), making plant species vulnerable to a decline (Miller et al. 2019). Local knowledge of the threat factors of C. toka was dissimilar among the ethnolinguistic groups, generations, and sexes due to the diversity of cultures. Potential traditional solution to the threat Three of the five concepts of the Global Strategy for Plant Conservation are the con- servation of the species and its habitat, sustainable use, and promotion of education and awareness (CBD 2002). Planting remains the main solution to combat the threat in the BCZ. Although the sacred species C. toka was rare and extinct in some areas, no individuals were found planted near houses, such as in northern Cameroon, where C. toka was planted for agro-silvopastoral purposes (Neba 2009). Additionally, C. toka was planted in farmland in Ethiopia (Rolkier and Abebe 2015). Most rural residents agreed to plant C. toka on their farmlands and in public places (markets, administra- tions, and schools) because they believed it was the best way to save the species. Some rural residents have decided not to plant it in their compounds because they know that C. toka is a massive plant. Furthermore, the mystical nature of C. toka may have discouraged locals from domesticating it. The second possible solution was the in-situ conservation of C. toka and its habitat (13%) to protect it from all human activities, including animal grazing, bushfires, and cutting of saplings and adult trees. Farmers must respect the 100-metre limit on riverbanks for the conservation of natural habitat. Respondents believed that farming within 100 meters of the riverbanks could cause siltation of water bodies and affect species regeneration. Agricultural activities such as tillage and ploughing cause the siltation of streambeds, resulting in the loss of the origi- nal water source (Kumar et al. 2021) and shortening its useful life (Poleto and Beier 2012). However, the conservation of habitats may be the best solution to the threat because seeds could be obtained from the remains of individuals and could be used to produce seedlings in nurseries. Seedlings have the potential to aid in reforestation and soil restoration. For instance, C. toka could be used as a keystone plant to restore deeply destroyed ecosystems. Furthermore, reintroducing C. toka into a restoration framework can aid in the prevention of extinction. The main solution to extinction is in situ and ex-situ conservation of a species (Oldfield 2003). Furthermore, invasive species should be removed from the habitat to reduce competition. According to Bar- ney et al. (2013), invasive alien species alter nutrient pools and fire regimes. However, rural people stated that C. toka is scarcer and more threatened than Vitellaria paradoxa C.EGaertn., Lannea microcarpa Engl. & K. Krause, Parkia biglobosa (Jacq.) R. Br. ex G. Don, Bombax costatum Pellegr. & Vuillet, Adansonia digitata L., and yet it is not protected. To reduce the rate of decline of C. toka, local people suggested associat- ing crops with C. toka. We recommend in situ, ex-situ, and circa-situ conservation of C. toka. Circa-situ conservation is a successful conservation strategy in traditional 218 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) agroforestry systems and backyard gardens (Sanchez et al. 2010; Lokonon et al. 2021). As such, we recommend that local communities increase their capacity to cultivate the species and replant it in traditional agricultural landscapes and home gardens, as well as promote youth education about good practices and harvesting techniques for plant parts used in food, fodder, medicine, or other specific uses. Conclusion This study has shown that the local people of the Sudanian and Sudano-Sahelian areas are aware of the ecological status of C. toka, as well as the potential driving factors influencing species dynamics. Ce/tis toka was described to be in a state of decline and extinction (in the Sudano-Sahelian zone) due to anthropogenic activities combined with climate change, lack of regeneration and species failure. Moreover, efforts should perhaps be concentrated on the domestication of C. toka to enhance regeneration and increase production. Conservation efforts should perhaps focus on C. toka and its habi- tat. However, most of the local future potential solutions included planting; conserva- tion of the species, its seeds, regeneration, and its habitat; avoidance of the overuse of C. toka; fire protection; association of C. toka in farmland; and promoting education and awareness of youth about C. toka. The incorporation of local people’s percep- tions into policymaking is of critical importance in C. toka management and for its sustainable conservation strategies. The findings of this study will aid the conservation of the critically endangered species C. toka at the national level by informing future environmental and biodiversity conservation efforts. Moreover, C. toka could be used to rehabilitate and restore degraded ecosystems to promote the recovery of the species. Acknowledgements We gratefully acknowledge the German Federal Ministry of Education and Research (BMBF) and West African Science Centre for Climate Change and Adapted Land Use (WASCAL) for providing the scholarship and financial support. This article is the result of a truly collective effort. First, we express our sincere gratitude to all field guides and translators for providing guidance and linguistic editing in the field. We ac- knowledge all the interviewees who agreed to share their expertise. We would also like to thank Mrs Alpha Karbgo and Ugbor Ogechi Nnabuchi. Finally, we would like to recognize the anonymous reviewers for their insightful comments on this manuscript. References Abba Idris S id, Halima Mohammed A (2020) Phytochemical screening, antimicrobial and antioxidant activities of Punica Grantum Peel. International Journal of Scientific Re- Local perception of the current state and threat factors... 219 search and Engineering Development 4(2): 13-21. https://doi.org/10.46718/JBG- SR.2020.01.000020 Achigan-Dako EG, Pasquini MW, Assogba-Komlan F, N’danikou S, Yéedomonhan H, Dansi A, Ambrose-Oji B (2010) Traditional Vegetables in Benin. Institut National des Recherches Agricoles du Bénin. Imprimeries du CENAP, Cotonou, July 2014, 283 pp. https://doi. org/10.13140/RG.2.1.1803.1121 Agbeshie AA, Abugre S, Atta-Darkwa T, Awuah R (2022) A review of the effects of forest fire on soil properties. Journal of Forestry Research 33(5): 1419-1441. https://doi.org/10.1007/ s11676-022-01475-4 Akoegninou A, van der Burg WJ, van der Maesen LJG (2006) Flore Analytique du Benin. 1063 pp. https://library.wur.nl/WebQuery/wurpubs/347966 Al-Khulaidi AWA (2018) Main vegetation types of the Wadi Rijaf, Jabal Bura’ protected area, Yemen. Journal of Basic and Applied Sciences 2(1): 21-35. https://www.academia. edu/41063025/Main_Vegetation_Types_of_the_Wadi_Rijaf_Jabal_Bura_Protected_ Area_Yemen Alfaifi MM, Al-khulaidi AW, Alaklabi A, Al-Gifri AN, Al-Al Faify EA (2021) New record of vascular plant for the flora of Saudi Arabia: Celtis toka (Forssk.) Hepper and Wood, Can- nabaceae. International Journal of Current Research in Biosciences and Plant Biology 8(7): 1-6. https://doi.org/10.20546/ijcrbp.2021.807.001 Amoutchi Al, Mehner T, Ugbor ON, Kargbo A, Paul KE (2021) Fishermen's perceptions and experiences toward the impact of climate change and anthropogenic activities on fresh- water fish biodiversity in Céte d'Ivoire. Discover Sustainability 2(1): 1-18. https://doi. org/10.1007/s43621-021-00062-7 Arbonnier M (2019) Arbres, Arbustes et Lianes des Zones Séches d’Afrique de l'Ouest, (Quat- riéme édition). Quae, MNHN, 779 pp. https://www.amazon.de/-/en/Michel-Arbonnier/ dp/275922547X Arkell AJ (1947) Early khartoum. Antiquity 21(84): 172-181. https://doi.org/10.1017/ S0003598X00016653 Awas T (1997) A study on the ecology and ethnobotany of non-cultivated food plants and wild relatives of cultivated crops in gambella region, southwestern Ethiopia. Degree of Master of Science in Biology in the Addis Ababa University (Issue June), 132 pp. http://etd.aau. edu.et/handle/123456789/8073 Badiane M, Camara B, Ngom D, Diedhiou MAA (2019) Perception communautaire des parcs agroforestiers traditionnels 4 Faidherbia albida (Del.) Chev. en Basse Casamance, Sénégal. Af- rique Science 15(1): 214-226. http://curis.ku.dk/ws/files/20647024/faidherbia_albida_int.pdf Bareke T (2018) Lowland semi-—evergreen forest of Ethiopia. Forestry Research and Engineer- ing: International Journal 2(5): 244-248. https://doi.org/10.15406/freij.2018.02.00057 Barney JN, Tekiela DR, Dollete ESJ, Tomasek BJ (2013) What is the “real” impact of invasive plant species? The Ecological Society of America. Frontiers in Ecology and the Environ- ment 2005(6): 322-329. https://doi.org/10.1890/120120 Bayala J, Kindt R, Belem M, Kalinganire A (2011) Factors affecting the dynamics of tree diver- sity in agroforestry parklands of cereal and cotton farming systems in Burkina Faso. New Forests 41(3): 281-296. https://doi.org/10.1007/s11056-010-9222-z 220 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) Betti JL, Yemefa ASRM (2011) Contribution 4 la connaissance des produits forestiers non ligneux du parc national de Kalamaloué, Extréme-Nord Cameroun: Les plantes alimen- taires. International Journal of Biological and Chemical Sciences 5(1): 291-303. https:// doi.org/10.4314/ijbcs.v5i1.68105 Betti JL, Yemefa’A SRM, Tarla FN (2011) Contribution to the knowledge of non wood forest products of the far north region of Cameroon : Medicinal plants sold in the Kousséri mar- ket. Journal of Ecology and the Natural Environment 3(7): 241-254. Bizimana N, Tietjen U, Zessin K, Diallo D, Djibril C, Melzig ME Clausen P (2006) Evalua- tion of medicinal plants from Mali for their in vitro and in vivo trypanocidal activity. Jour- nal of Ethnopharmacology 103(3): 350-356. https://doi.org/10.1016/j.jep.2005.08.023 Blench R (2000) Trees on the March: the Dispersal of Economic Trees in the Prehistory of West-Central Africa. Odi, 15 pp. Bloesch U (2014) Forest Mapping and Pre-Inventory of the Sudanese Refugee Hosting Areas in Maban and Pariang Counties. South Sudan Mission report part A (Issue May), 34 pp. https://doi.org/10.13140/RG.2.1.1013.0327 Boussim IJ, Guinko S, Tuquet C, Sall G (2004) Mistletoes of the agroforestry park- lands of Burkina Faso. Agroforestry Systems 60(1): 39-49. https://doi.org/10.1023/ B:AGFO.0000009403.36419.20 Bridges KW, Lau YH (2006) The skill acquisition process relative to ethnobotanical methods. Eth- nobotany Research and Applications 4: 115-118. https://doi.org/10.17348/era.4.0.115-118 CBD (1992) 8 convention on biological diversity. Rio de Janeiro, 5 June 1992 (Vol. 2, Is- sue June), 214 pp. https://treaties.un.org/doc/Treaties/1992/06/1992060508-44PM/ Ch_XXVIIL_08p.pdf CBD (2002) Report of the Sixth Meeting of the Conference of the Parties to the Convention on Biological Diversity, 341 pp. https://www.cbd.int/meetings/COP-06 Dansi A, Adjatin A, Adoukonou-sagbadja H, Adomou AC, Yedomonhan H, Akpagana K, Foucault BDe, Dansi A, Adjatin A, Adoukonou-sagbadja H, Adomou AC, Yedomonhan H, Akpagana K, Foucault BDe (2013) Traditional leafy vegetables in Benin: folk nomen- clature, species under threat and domestication. Acta Botanica Gallica 8078(156:2): 183- 199. https://doi.org/10.1080/12538078.2009.10516150 de Albuquerque UP, Hanazaki N (2009) Five problems in current ethnobotanical research — And Some Suggestions for Strengthening Them. Human Ecology: an Interdisciplinary Journal 37(5): 653-661. https://doi-org/10.1007/s10745-009-9259-9 Diatta K, Diatta W, Fall AD, Ibra S, Dieng M, Mbaye AI, Manga I (2019) Ethnobotanic Sur- vey of Aids Opportunistic Infections in the Ziguinchor District, Sénégal. Asian Journal of Research in Medical and Pharmaceutical Sciences 8(1—2): 1-10. https://doi.org/10.9734/ ajrimps/2019/v8il-230130 Djégo-Djossou S, Koné I, Fandohan AB, Djégo JG, Huynen MC, Sinsin B (2015) Habitat Use by White-Thighed Colobus in the Kikélé Sacred Forest: Activity Budget, Feeding Ecol- ogy and Selection of Sleeping Trees. Primate Conservation 29(1): 97-105. https://doi. org/10.1896/052.029.0106 Doerr SH, Santin C (2016) Global trends in wildfire and its impacts: Perceptions versus realities in a changing world. Philosophical Transactions of the Royal Society of London, Series B, Biologi- cal Sciences 371(1696): e20150345. http://dx.doi.org/10.1098/rstb.2015.0345 Local perception of the current state and threat factors... 221 Fall AD, Ibra S, Dieng M, Diatta-badji K, Diatta W, Bassene E (2017) Phytochemical screen- ing, phenol content and antioxidant studies of ethanol leaf extract of Celtis toka (Forssk.) Hepper & J.R.I. Wood. Journal of Pharmacognosy and Phytochemistry 6(1): 488-492. https://www.phytojournal.com/archives/2017/vol6issue1/PartG/5-6-58-561.pdf Franklin JE Shugart HH, Harmon ME (1987) Death as an ecological process: The causes, consequences, and variability of tree mortality. Bioscience 37(8): 550-556. https://doi. org/10.2307/1310665 Friedman J, Yaniv Z, Dafni A, Palewitch D (1986) A preliminary classification of the healing potential of medicinal plants, based on a rational analysis of an ethnopharmacological field survey among Bedouins in the Negev Desert, Israel. Journal of Ethnopharmacology 16(2-3): 275-287. https://doi.org/10.1016/0378-8741(86)90094-2 Gaoue OG, Sack L, Ticktin T (2011) Human impacts on leaf economics in heterogeneous landscapes: The effect of harvesting non-timber forest products from African mahogany across habitats and climates. Journal of Applied Ecology 48(4): 844-852. https://doi. org/10.1111/j.1365-2664.2011.01977.x Garzuglia M (2006) Threatened, Endangered and Vulnerable Tree Species: a Comparison Be- tween FRA2005 and the IUCN Red list. FAO Forestry Department, 108/E, Rome, 18 pp. http://azkurs.org/pars_docs/refs/26/25854/25854.pdf Gilbert T, Flore NJ, Claudette B, Pierre K, Moksia KF Adamou I (2019) Ethnobotanical study of indigenous woody plants in traditional agroforestry of the Sudano-Sahelianzone of Came- roon: Case of Mandara Mountains. International Journal of Agriculture & Environmental Science 6(6): 1-8. https://doi.org/10.14445/23942568/AES-VG6IG6P 101 Gonzalez P (2001) Desertification and a shift of forest species in the West African Sahel. Cli- mate research. Climate Research 17: 217-228. https://doi.org/10.3354/cr017217 Gonzalez P, Tucker CJ, Sy H (2012) Tree density and species decline in the African Sahel at- tributable to climate. Journal of Arid Environments 78: 55—64. https://doi.org/10.1016/j. jaridenv.2011.11.001 Hahn-hadjali K, Thiombiano A (2000) Perception des espéces en voie de disparition en mi- lieu gourmantché (est du Burkina Faso). Berichte des Sonderforschungsbereichs 268(14); 285-297. https://d-nb.info/1106135997/34 Hamid MMA, Kordofani MAY (2015) Taxonomic Study of Trees and Shrubs of Zalingei Area West Darfur State- Sudan. International Journal of Scientific Research 4(10): 2319-7064. https://www.ijsr.net/archive/v4il0/SUB159038. pdf Harris FMA, Mohammed S (2003) Relying on nature: Wild foods in northern Nigeria. Ambio 32(1): 24-29. https://doi.org/10.1579/0044-7447-32.1.24 Hauman L (1942) Note sur les Ulmacées du Congo Belge. Botanic Garden Meise 16(4): 407— 412. https://www.jstor.org/stable/3666743 Hohn A, Neumann K (2016) The Palaeovegetation of Janruwa (Nigeria) and its Implications for the Decline of the Nok Culture. Journal of African Archaeology V 14(3): 331-353. https://doi.org/10.3213/2191-5784-10296 Houéhanou DT, Assogobadjo AE, Chadare FJ, Zanvo S, Sinsin B (2016) Approches mé- thodologiques synthétisées des études d’ethnobotanique quantitative en milieu tropical. Methods for sampling and analysis of field data to evaluate and monitor vegetation in Africa 20, 195-205. 222 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) Ifeanyiobi CC, Etuk UR, Jike-wai O (2012) Climate change, effects and adaptation strategies; Implication for agricultural extension system in Nigeria. Greener Journal of Agricultural Sciences 2(2): 053-060. https://doi.org/10.15580/GJAS.2013.3.1234 IPPC (2021) Climate Analytics (2021) 1.5°C to survive: evidence from the IPCC Special Re- ports. https://climateanalytics.org/publications/2021/15c-to-survive-evidence-from-the- ipcc-special-reports/ Irvine FR (1961) Woody Plants of Ghana with Special Reference to Their Uses. Oxford Uni- versity Press, London, 143-144. https://www.scirp.org/(S(vtj3fa45qm lean45vwvffcz55))/ reference/ReferencesPapers.aspx? ReferenceI D=1769954 Ismail MI, Elawad AA (2015) Checklist of plants of Rashad and Alabassia localities (eastern Nuba Mountains). Check List 11(6): 1-9. https://doi.org/10.15560/11.6.1805 IUCN (2019) Botanic Gardens Conservation International (BGCI) & IUCN SSC Global Tree Specialist Group. 2019. Celtis toka. The IUCN Red List of Threatened Species 2019: e.T144137137A149001782. [The IUCN Red List of Threatened Species 8235: 7.] https:// doi.org/10.2305/IUCN.UK.2019-2.RLTS.T144137137A149001782.en IUCN (2020) Guidance for using the IUCN Global Standard for Nature-based Solutions. A user-friendly framework for the verification, design and scaling up of Nature-based Solutions. 1*edn. IUCN, Gland, Switzerland, 78 pp. https://doi.org/10.2305/IUCN.CH.2020.09.en IUCN (2021) Issues briefs. Forests and climate change. IUCN, Gland, Switzerland, 2 pp. https://www.iucn.org/resources/issues-brief/forests-and-climate-change Kiee M, Zach B, Neumann K (2000) Four thousand years of plant exploitation in the Chad Basin of northeast Nigeria I: The archaeobotany of Kursakata Marlies. Vegetation History and Archaeobotany 9(4): 223-237. https://doi.org/10.1007/BF01294637 Kubmarawa D, Magomya AM, Yebpella GG, Adedayo SA (2011) Nutrient content and amino acid composition of the leaves of Cassia tora and Celtis integrifolia. Internagtional Research Journals of Biochemistry and Bioinformants 1(9): 222-225. https://www.interesjournals. org/articles/nutrient-content-and-amino-acid-composition-of-the-leaves-of-cassia-tora- and-celtis-integrifolia. pdf Kumar N, Kumar A, Marwein BM, Verma DKIJ, Kumar A, Ramamoorthy D (2021) Agricul- tural activities causing water pollution and its mitigation — a review. International Journal of Modern Agriculture 10(1 SE-): 590-609. http://modern-journals.com/index.php/ijma/ article/view/632 Lericollais A (1990) La gestion du paysage : Sahélisation, surexploitation et délaissement des terroirs sereer au Sénégal. In: Richard J-F (Ed.) La Dégradation des Paysages en Af- rique de Ouest: Points de vue et Perspectives de Recherches. Ministére de la Coopé- ration et du développement; Presse Universitaires de Dakar, Paris (FRA) & Dakar, 151-169. https://horizon.documentation.ird.fr/exl-doc/pleins_textes/pleins_textes_7/b_ fdi_03_01/35485.pdf Lokonon BE, Sodoté FE, Kakai RG (2021) Use of local knowledge for contributing to the con- servation of Caesalpinia bonduc (L.) Roxb in southern Benin (West Africa). Global Ecology and Conservation 27: 1-14. https://doi.org/10.1016/j.gecco.2021.e01551 Lykke AM, Kristensen MK, Ganaba S (2004) Valuation of local use and dynamics of 56 woody species in the Sahel. Biodiversity and Conservation 13(10): 1961-1990. https://doi. org/10.1023/B:BIOC.0000035876.39587.1a Local perception of the current state and threat factors... 225 Mahre MB, Umaru B, Ojo NA, Saidu AS, Yahi D, [brahim RM, Mshelbwala P (2017) Acute Toxicity, Phytochemistry and Anti-diarrheal Effects of Celtis integrifolia Lam. Aqueous Leaf Extract in Wistar Albino Rats. British Journal of Pharmaceutical Research 14(5): 1-7. https://doi.org/10.9734/BJPR/2016/31222 Mballow AE, Kahwa I, Abdelgadir AA, Adelina T, Ogwang PE (2020) Traditional approaches and medicinal plants in treatment of epilepsy in West and East Africa. NeuroPharmac Journal 5: 121-130. https://doi.org/10.37881/1.521 Miller M, Findley J (2014) CHAPTER VI — PLANTS. Fire Effects Guide, 313 pp. Miller RG, Tangney R, Enright NJ, Fontaine JB, Merritt DJ, Ooi MKJ, Ruthrof KX, Miller BP (2019) Mechanisms of fire seasonality effects on plant populations. Trends in Ecology & Evolution 34(12): 1104-1117. https://doi.org/10.1016/j.tree.2019.07.009 Moksia F, Azaria D, Konsala S, Yougouda H, Gilbert T Tchobsala (2019) Structure, dynamics and impact of the exploitation of the woody plants of woodlands in the Sudano — sahelian zones, North Cameroon. International Journal of Advanced Research in Biological Sci- ences 6: 201-220. http://dx.doi.org/10.22192/ijarbs.2019.06.03.011 Muazu J, Kaita AH (2008) A review of traditional plants used in the treatment of epilepsy amongst the hausa/fulani tribes of northern Nigeria. African Journal of Traditional, Com- plementary, and Alternative Medicines 5(4): 387-390. https://doi.org/10.4314/ajtcam. v5i4.31294 Nacoulma BMI, Lykke AM, Traoré S, Sinsin B, Thiombiano A (2017) Impact of bark and foliage harvesting on fruit production of the multipurpose tree Afgelia africana in Bur- kina Faso (West Africa). Agroforestry Systems 91(3): 565-576. https://doi.org/10.1007/ s10457-016-9960-9 Nacoulma MIB, Ouédraogo I, Ouédraogo O, Dimobé K, Thiombiano A (2018) Phytodiver- sity of Burkina Faso: Selected Countries in Africa. Global Biodiversity 3: 1-33. https://doi. org/10.1201/9780429469800-1 Nakagawa N (2008) Despotic wild Patas Monkeys (Erythrocebus patas) in Kala Maloue, Cameroon. American Journal of Primatology 70(3): 238-246. https://doi.org/10.1002/ ajp.20481 Neba NE (2009) Management of woody plants in indigenous land use systems of the Sahel : Example of north Cameroon. International NGO Journal 4(11): 480-490. [Management of woody plants in indigenous land use systems of the Sahel] Neumann K (1992) Une flore soudanienne au Sahara central vers 7000 B.P: les charbons de bois de Fachi, Niger, Bulletin de la Société Botanique de France. Actualités Botaniques 139: 2-4. [565-569] https://doi.org/10.1080/01811789.1992.10827128 Ogungbenro RO, Oluwalana SA, Adedokun MO, Omosekeji RB (2018) Ethnobotancial and Phytochemical studies of some blood-cleansing Herbs in Oyo and Ogun States, Southwest- ern Nigeria. Journal of Advanced Botany and Zoology 6(2): 1-8. https://doi.org/10.5281/ zenodo. 1250060 Oldfield S (2003) Plant extinction — threats and solutions. 3‘ Global Botanic Gardens Con- gress, 7 pp. https://www.bgci.org/files/Wuhan/PlenaryAddresses/Oldfield. pdf Osue HO, Lawani FAG, Njoku CI (2018) Factors Affecting Sustainable Animal Trypanoso- mosis Control in Parts of Kaduna State, Nigeria. Journal of Agricultural Extension 22(1): 157-174. https://doi.org/10.4314/jae.v22il.1 224 Zainabou Dabré et al. / Nature Conservation 51: 189-225 (2023) Otry ME, Laflamme G (2009) Fungi and diseases — Natural components of healthy forests. Botany 87(1): 22-25. https://doi.org/10.1139/B08-090 Piqué R, Gueye M, Hardy K, Camara A, Dioh E (2016) Not Just Fuel: Food and Technology from Trees and Shrubs in Falia, Saloum Delta (Senegal). Ethnoarchaeological Research 6: 1-14. https://doi.org/10.1007/978-3-319-23153-2_17 Poleto C, Beier EV (2012) Siltation and Erosion Processes on a tributary of lake Itaipu due a dam reservoir. Lakes, Reservoirs and Ponds 6(2): 108-119. https://www.limnology.ro/ Lakes/2012/201206207.pdf R Core Team (2021) R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna. https://www.R-project.org/ Rabeil T (2003) Distribution potentielle des grands mammiféres dans le Parc du W au Niger. Thése. Université Paris VII — Dénis Diderot UFR GHSS. https://tel-archives-ouvertes.fr/ tel-0000693 1/file/tel-00006931.pdf Rolkier GG, Abebe T (2015) Agroforestry Potentials of Under-Exploited Multipurpose Trees and Shrubs (MPTS) in Lare Woreda of Gambella Region, Ethiopia. The International Journal of Science & Technoledge 3(9): 23-40. https://www.internationaljournalcorner. com/index.php/theijst/article/view/124648/85675 Sanchez AC, Osborne PE, Haq N (2010) Identifying the global potential for baobab tree cul- tivation using ecological niche modelling. Agroforestry Systems 80(2): 191-201. https:// doi.org/10.1007/s10457-010-9282-2 Sattarian A (2006) Contribution to the Biosystematics of Celtis L. (Celtidaceae) with Spe- cial Emphasis on the African Species. PhD thesis Wageningen University, Wageningen, 150 pp. https://edepot.wur.nl/121819 Sattarian A, Van Der Maesen LJG (2005) Two new species of Ce/tis (Celtidaceae) from Australia and Madagascar. Blumea 50(3): 499-503. https://doi.org/10.3767/000651905X622752 Savadogo S, Thiombiano A (2010) Sacred groves and community forests. In: Thiombiano A, Kampmann D (Eds) Biodiversity Atlas of West Africa (Vol. II): Burkina Faso. Ouagadou- gou and Frankfurt/Main, 625 pp. https://publikationen.ub.uni-frankfurt.de/frontdoor/ index/index/year/2019/doclId/48641 Savadogo S, Kabore A, Thiombiano A (2017) Caractéristiques végétales, typologie et fonctions des bois sacrés au Burkina Faso. International Journal of Biological and Chemical Sciences 11(4): e1497. https://doi.org/10.4314/ijbcs.v11i4.8 Seignobos C, Tourneux H (2002) Le Nord-Cameroun 4 travers ses mots: Dictionnaire de termes anciens et modernes. Karthala, Dictionnaires et Langues, Henry Tourneux. 00458682 HAL, 334 pp. https://horizon.documentation.ird.fr/exl-doc/pleins_textes/ pleins_textes_7/b_fdi_03_05/0100273 Seignobos C (2014) Essai de Reconstitution des Agrosystémes et des Ressources Alimentaires Dans les Monts Mandara (Cameroun) des Premiers Siécles de Notre ére aux Années 1930. Revue d’ethnoécologie, 51 pp. https://doi.org/10.4000/ethnoecologie. 1836 Shepherd G (1992) Managing Africa’s Tropical Dry Forests: a review of indigenous meth- ods. e Overseas Development Institute, Regent's College, London, 124 pp. https:// odi.org/en/publications/managing-africas-tropical-dry-forests-a-review-of-indigenous- methods/ Local perception of the current state and threat factors... 225 Sop TK, Oldeland J (2011) Local Perceptions of Woody Vegetation Dynamics in the Context of a “Greening Sahel”: A Case Study from Burkina Faso. Land Degradation & Develop- ment, 21 pp. https://doi.org/10.1002/Idr.1144 Sop TK, Oldeland J, Bognounou FE, Schmiedel U, Thiombiano A (2012) Ethnobotanical knowledge and valuation of woody plants species: A comparative analysis of three ethnic groups from the sub-Sahel of Burkina Faso. Environment, Development and Sustainability 14(5): 627-649. https://doi.org/10.1007/s10668-012-9345-9 Suchocka M, Swoczyna T, Kosno-Jonczy J, Kalaji HM (2021) Impact of heavy pruning on development and photosynthesis of Tilia cordata Mill. trees. PLoS ONE 16(8): e0256465. https://doi.org/10.1371/journal.pone.0256465 Tchobsala HB, Haman B, Gilbert H, Paul K, Danra DD, Denis K (2022) Socio-economic and environmental influences of firewood exploitation in Bongor and its surroundings (Chad). Environmental Challenges 6: ¢100406. https://doi.org/10.1016/j.envc.2021.100406 Teklehaymanot T, Giday M (2010) Ethnobotanical study of wild edible plants of Kara and Kwego semi-pastoralist people in Lower Omo River Valley, Debub Omo Zone, SN- NPR, Ethiopia. Journal of Ethnobiology and Ethnomedicine 23(1): 1-8. https://doi. org/10.1186/1746-4269-6-23 Theodory TF (2016) Dealing with Change: Indigenous Knowledge and Adaptation to Climate Change in the Ngono River Basin, Tanzania. PhD Thesis, Rheinische Frie- drich-Wilhelms-University of Bonn, Germany, 251 pp. https://nbn-resolving.org/ urn:nbn:de:hbz:5n-44638 Thiombiano A, Schmidt M, Da S, Hahn-hadjali K, Zizka G, Wittig R (2010) Vascular plants: flowering plants. In: Thiombiano A, Kampmann D (Eds) Biodiversity Atlas of West Africa (Vol. II): Burkina Faso. Ouagadougou and Frankfurt/Main, 625 pp. Thiombiano A, Schmidt M, Dressler S, Hahn K, Zizka G (2012) Catalogue des plantes vascu- laires du Burkina Faso. 405 pp. Thiombiano A, Kakai RG, Bayen P, Boussim JI, Mahamane A (2016) Méthodes et dispositifs d’inventaires forestiers en afrique de l’ouest: état des lieux et propositions pour une harmo- nisation. Methods for sampling and analysis of field data to evaluate and monitor vegeta- tion in Africa (Vol. 20), 218 pp. Tsabang N, Guedje MN, Fokunang C, Dongmo S, Tchokouaha YLR, Tsouh FPV, Jiofack R, Protus AT, Nouidui C, Fekam BF (2016) Ethnopharmacological and Ethnomedical Study of Anti- Epileptic Plants used in Traditional Medicine in Yaounde and its Surroundings Areas (Cameroon). Journal of Biological and Chemical Research 35(1): 496-509. Vivien J (1990) Fruitiers sauvages du Cameroun. (fin). Agritrop 45(4): 413-426. https://agri- trop.cirad.fr/436558/1/436558.pdf Vodouhe R, Atta-Krah K, Achigan-Dako GE, Eyog-Matig O, Avohou H [Eds] (2007) Plant genetic resources and food security in West and Central Africa. Regional Conference, 26-30 April 2004. Bioversity International, Rome, 746 pp. https://www.bioversityinternational.org/e-li- brary/publications/detail/plant-genetic-resources-and-food-security-in-west-and-central-africa/ Watrin J, Lézine A-M, Gajewski K, Vincens A (2007) Pollen — plant — climate relationships in sub-Saharan Africa. Journal of Biogeography 34(3): 489-499. https://doi.org/10.1111/ j-1365-2699.2006.01626.x