The treatment of indigenous and local knowledge (ILK) in climate research has emerged in all fields of impact and vulnerability assessment, mitigation, and adaptation – the key topics that are considered in climate change studies. While more attention has been given on the intersections of ILK and impact assessment (Boillat and Berkes, 2013; Panda, 2016; Savo et al., 2016; Weber and Schmidt, 2016; Whitney et al., 2020) and ILK and adaptation (Reid, 2016; Makondo and Thomas, 2018; Nalau et al., 2018; Taylor et al., 2023), few studies have examined the topics of ILK and climate change mitigation. This limitation emerges against a backdrop of increasing need to mitigate greenhouse gas (GHG) emissions to avoid dangerous climate change (IPCC, 2022). To avoid global warming of 1,5°C or higher above pre-industrial levels, a scenario feared to result in disruptive climate change, the climate change community urges urgent and ambitious mitigation actions (Altieri and Nicholls, 2017; Giannakidis et al., 2018; IPCC, 2022). Mitigation is understood as an approach to cut GHG emissions or to enhance their sinks (Nyong et al., 2007). Mitigation is required to stabilise global warming and slow down climate change to reduce pressure on adaptation, which hitherto has proven to be challenging (Panda, 2016; IPCC, 2022). The climate mitigation community is increasingly acknowledging the role of indigenous and local people (ILP) in efforts to enhance carbon sinks and mitigate climate change. In this study, we use the term ILK to refer to detailed knowledge encompassing indigenous knowledge and local knowledge held by indigenous and local people and developed from their many years of interacting with the environment, the knowledge of which is useful for mitigating climate change. This joint treatment of indigenous knowledge and local knowledge has been preferred to deal with the overlaps that exist in the use of these knowledge forms. Indigenous knowledge is culturally unique, context specific, mainly transmitted intergenerationally and developed after many years of experiencing environmental phenomena. Local knowledge refers to knowledge developed from constant experiences and learning about changes happening in people’s environment and may not necessarily have the long span characteristic of indigenous knowledge (Boillat and Berkes, 2013; Makondo and Thomas, 2018). Collectively, the knowledge, experiences and practices can be used to provide ways of limiting carbon emissions or enhance their sinks.

However, compared to studies on ILK and adaptation, studies that look at the overlaps of ILK and climate change mitigation are still fewer. There has been more attention on ILK-adaptation relationships perhaps owing to the ethical question about not putting the burden of mitigation on indigenous people. Our point of departure is to deploy a systematic review of literature that examines the overlap of ILK and climate change mitigation to give nuances on how this connection has been studied. We go beyond identifying case studies of this overlap to identifying the knowledge, ways, practices and experiences of ILP that show mitigation benefits; and mapping the location of these cases.

Several reasons have been provided to explain why indigenous and local communities matter in climate mitigation. First, ILP are closely connected to forests and ecosystems (Kuh, 2012; Vergara-Asenjo and Potvin, 2014; Alejo et al., 2021) that have the potential to sequester significant amounts of carbon dioxide given that they occupy up to 65% of the world’s land [Rights and Resources Initiative (RRI), 2015] and manage approximately 28% of the global land surface (Clay and Cooper, 2022) and directly manage about 11% of the world’s forests [Rights and Resources Initiative (RRI), 2015]. It is estimated that about 20% of carbon is stored in the regions with indigenous people influence (Brack, 2019). Second, indigenous peoples and local communities are disproportionately affected by climate change impacts, yet they have contributed the least to global warming (Nyong et al., 2007). Third, indigenous communities inhabit areas that are prone to the effects of climate change, such as small islands, mountain regions, coastal regions and drylands and are among the poorest and most marginalized people globally (Ramos-Castillo et al., 2017; Jones, 2019). Fourth, they have predominantly natural resource dependent livelihoods that are sensitive to climatic disruptions (Chanza and Musakwa, 2021a). Fifth, and vitally important, many communities of indigenous people are long-time observers of changes in their local environments, many hold religious beliefs about such changes and their knowledge is useful in environmental monitoring (Brattland et al., 2019). Sixth, climate change interventions such as afforestation projects may also interfere with the rights and livelihoods of ILP (Jones, 2019). Seventh, the success of mitigation projects may only be realised with the full participation of indigenous communities (Robinson et al., 2014; Ramos-Castillo et al., 2017).

Systematic reviews involve replicable and robust reviews of literature as they specify procedures and protocols to guide a scientific field of enquiry (Hallinger, 2013; Linnenluecke et al., 2020; Kraus et al., 2022). Hallinger (2013) stressed that a systematic research synthesis adheres to transparent methods involving a standard set of stages that are accountable, replicable and updateable to ensure reports are relevant and useful. Our study sets to locate and analyse cases that show the engagement of indigenous and local people in climate mitigation research and practice. This contribution is against a background of growing acknowledgement of the role of ILP in mitigation action (Ramos-Castillo et al., 2017; Jones, 2019; Maru et al., 2023). However, very few studies have used a systematic review to collate the evidence of overlaps between ILK and climate change mitigation. The synthesis of this evidence is timely to enhance understanding of opportunities that exist when indigenous and local people are incorporated in mitigation research and action. As this interest grows, there is fear that hurried approaches of prescribing mitigation projects that are not appropriate to indigenous communities may end up jeopardising the objectives of climate change mitigation (Ramos-Castillo et al., 2017; Jones, 2019).

We have set our research objectives as: (a) To identify case studies that examine the overlaps of ILK and climate change mitigation; (b) to analyse the methods used for engaging ILP in mitigation studies; (c) to document the mitigation benefits that emerge from indigenous and local people’s knowledge, experiences and practices; (d) to characterise concepts that connect ILK and climate change mitigation; and (e) to show the direction of ILK and climate change mitigation research. In the next section, we examine the intersection of ILK and climate mitigation. Later on, we show how we conducted the systematic review of available studies before presenting and discussing the results.

Participation of indigenous people in knowledge development and planning for environmental management, under which the topic of climate change falls, is particularly governed by the United Nations Declaration on the Rights of Indigenous Peoples (UNDRIP), the Convention on Biological Diversity (CBD), the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), and the International Indigenous’ Peoples Forum on Climate Change (IIPFCC). The UNDRIP acknowledges that, ‘indigenous knowledge, cultures and traditional practices contribute to sustainable and equitable development and proper management of the environment’ (UN, 2007). Article 8(j) of the CBD specifies the need to ‘…respect, preserve and maintain knowledge, innovations and practices of indigenous and local communities … relevant for the conservation and sustainable use of biological diversity and promote their wider application with the approval and involvement of the holders of such knowledge…’ (UN, 1992). The IPBES recognises and works with ILP in ecosystem and biodiversity assessment studies (IPBES, 2019). Mitigation and adaptation practices of indigenous people are emphasised by IIPFCC (2012). Within these frameworks, concepts that highlight the intersection of ILP and climate change are nature’s contribution to people (NCP) and nature-based solutions (NbS). As a concept, nature’s contribution to people recognises the diversity of knowledge and worldviews in enhancing understanding of nature-people interactions (Ellis et al., 2019; Hill et al., 2021). In the context of climate mitigation, the knowledge and worldviews of ILP can be used to understand ecosystem status, manage ecosystems and monitor their quality. Similarly, NbS encompasses a broad approach of enhancing nature to solve challenges such as climate change and integrates approaches such as ecosystem-based adaptation (EbA), ecosystem-based mitigation (EbM) and nature climate solutions whose objectives are to reduce GHG emissions from ecosystems and harness their potential to store carbon dioxide (Cohen-Shacham et al., 2019; Seddon et al., 2021).

Mitigation efforts at the national level are now widely framed in the form of Nationally Determined Contributions (NDCs) following the 2015 Paris Agreement that sets to stabilise GHG emissions under the United Nations Framework Convention on Climate Change (UNFCCC). The NDCs are climate action plans to cut emissions and adapt to climate change. In its latest report, the Intergovernmental Panel on Climate Change (IPCC) states that up to 21% of global anthropogenic emissions comes from Agriculture, Forestry and Other Land Use (AFOLU) sector, with deforestation being responsible for 45% of total AFOLU emissions. However, this sector offers significant potential for sequestrating carbon to achieve the required GHG emission reduction targets. To reach these targets, actions would be required by all players, including indigenous and local communities. For example, ILP can participate through reducing deforestation and engaging in afforestation and reforestation projects. The UNFCCC has developed a carbon financing scheme known as Reducing Emissions from Deforestation and Forest Degradation (REDD+) whose implementation and success rely mainly on indigenous and local communities (Brugnach et al., 2017).

So far, studies examining the overlaps of ILK and climate change mitigation have not advanced with the pace and urgency required to articulate the climate crisis. Available studies largely focused on the role of indigenous and local communities in mitigation (Martello, 2008; Salick et al., 2014; Chanza and Musakwa, 2021b; Kunz et al., 2022; Maru et al., 2023), including mitigation of climatic impacts (Ifejika Speranza et al., 2010; Hiwasaki et al., 2014; Schlingmann et al., 2021). In this study, however, we made a distinction between mitigation of climate change and mitigation of climatic impacts. We concentrated on the former that looks at measures to prevent or limit the occurrence of climate change and not the latter that can also be called adaptation, but not the focus of this paper. The studies identified here exist as isolated empirical contribution to the knowledge of what indigenous and local people can do to mitigate climate change in their unique contexts. Apparently, very few studies have made a systematic review of literature that show how these topics have evolved. Nair et al. (2009) reviewed 42 studies to understand the carbon sequestration potential of agroforestry but did not focus on indigenous communities. Von Seggern (2020) used a meta-ethnographic approach to synthesise empirical results of local and indigenous climate change adaptation and mitigation strategies. However, the review was only limited to selected South Pacific Island states and integrated both mitigation and adaptation. A collection of eight articles published as a special issue in Climatic Change in 2017 attempted to address the relationship between climate change mitigation and indigenous peoples. However, the focus of this collection was to identify policy measures that can be used to pursue the dual goals of indigenous sovereignty and climate change mitigation (Ramos-Castillo et al., 2017). To advance knowledge on the intersection of indigenous knowledge and climate change mitigation, it is timely to examine this connection and how ILK has been applied in mitigation studies.

Drawing on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) approach, we structured the data and analysis process into four main stages: database search, primary screening, secondary screening and tertiary screening (Figure 1). Database search sets the systematic review process by identifying keywords for use in the literature search based on what we aimed to achieve, that is, to understand how local and indigenous knowledge has been incorporated into climate change mitigation research. Conscious of the heterogenous deployment of indigenous knowledge terminology in literature, we included the following terms in our searches: ‘indigenous knowledge’; ‘indigenous knowledge systems’; ‘indigenous climate knowledge’; ‘traditional knowledge’; ‘traditional ecological knowledge’; ‘cultural knowledge’; ‘local knowledge’; and ‘local ecological knowledge’. For climate change mitigation, we used the terms ‘climate mitigation’; ‘climate change mitigation’; ‘mitigation of climate change’. We excluded studies on mitigation of climate change impacts since we were mainly interested in those that covered measures that contribute to GHG emission reduction or contribute to carbon sequestration. We then generated a search query that combines these words in Scopus and Web of Science (WoS) electronic databases as follows: (‘indigenous knowledge’ OR ‘indigenous knowledge system*’ OR ‘indigenous climate knowledge’ OR ‘traditional knowledge’ OR ‘cultural knowledge’ OR ‘traditional ecological knowledge’ OR ‘local knowledge’ OR ‘local ecological knowledge’ AND ‘climate mitigation’ OR ‘climate change mitigation’ OR ‘mitigation of climate change’). Scopus and WoS are the commonly used databases in systematic research (Hallinger, 2013; Nalau et al., 2018; Garcia-del-Amo et al., 2020). The search was conducted on 24 April 2023 and yielded a total of 162 publications from Scopus (n = 104) and WoS (n = 58) prior to screening (Figure 1).

The screening stages involved analysis of the search results for screening according to the inclusion criteria that we developed. The criteria consisted of the following: (1) an empirical study that focuses on local or indigenous knowledge and practices relevant in mitigating climate change; (2) use of the terms ILP or ILK or associated terminology; and (3) the research process involved participation of ILP. For the second stage, the identified total records (n = 162) were sorted according to source type (journal articles and book chapters) and language (English), leaving only relevant sources sought from Scopus (n = 82) and WoS (n = 51). We then removed duplicates (n = 23) to remain with only clean results (n = 96). At the third stage, we conducted further screening involving topic and abstract screening and removed articles that did not meet our set criteria (n = 16). Finally, the remaining articles (n = 70) were further subjected to content screening. The excluded publications (n = 27) were outside the scope of this review. These studies related to adaptation studies, studies covering mitigation of climate change impacts or mitigation of climatic risks, literature reviews or studies based on theoretical investigations rather than empirical cases. A total of 43 publications were finally considered for detailed content analysis.

In line with the set objectives of the study, we read through each of the 43 reports and structured the results as follows: (a) Place where the studies were conducted; (b) year of publication; (c) methods used for study and how the indigenous and local people were engaged; (d) the concepts that emerged from the joint treatment of ILK and climate change mitigation; and (d) the activities or practices that show the evidence of mitigation contribution. We summarised these results in a table for easy reference. For showing how these studies evolve over time, we plotted the results in a graph generated in Microsoft Excel. A map was also generated to show the location of these cases. Given the fewer cases considered in this study (n = 43), we preferred a qualitative analysis of the results to depict more content on the engagement of ILP in climate change mitigation research and projects and to better understand the practices that contribute to climate change mitigation. We continued to read through the result summaries as we synthesise the findings according to the identified themes. The results were largely qualitatively presented and analysed. We used tables to summarise some of the findings for easy inferences.

We have seen some growing interest in examining ILK and climate change mitigation since 2009. This interest exists in all regions of the world. It is most likely that this trend will be maintained as more focus is given on working with indigenous communities to stabilise GHG emissions through various projects across the globe. This rise in studies that connect these topics can be attributed to the following reasons. First, this could be in response to increased acknowledgement of the role of indigenous and local people in climate change mitigation that has been observed by other authors (Garcia-del-Amo et al., 2020; Chanza and Musakwa, 2021b; Maru et al., 2023). Second, this could stem from the increased acknowledgement of the problem of climate change that requires the need to break epistemological and methodological boundaries to work with ILK towards improved understanding of climate change (Ford et al., 2016; Fernandez-Llamazares et al., 2017). Third, the growing call for climate governance that requires that communities experiencing climatic disruptions should have a voice in framing climate adaptation and mitigation responses (Zelli, 2011). Fourth, the increased concern about ethical and equity issues in climate change discourses where calls are being made to include indigenous people who tend to be the worst victims of climatic disturbances despite their limited contribution to the problem (Jones, 2019). Fifth, the existence of platforms such as UNDRIP, IPBES and IIPFCC that recognise the rights of ILP in climate action. These platforms continue to propel the ILP-climate change agenda, including by the IPCC (Ford et al., 2016).

In terms of the methods of articulation, we have observed a spectrum of participatory methods in research and practice in the ILK-climate change mitigation nexus, ranging from more participatory to less participatory methods. These methods vary in the time taken to interact with ILP, the depth of the analysis used in knowledge co-production and role that ILP played in the research. Certain studies featured in this review spanned a period of a number of years and in some cases even decades. Where questionnaires and semi-structured interviews were used alone, these gave less time to interact with indigenous knowledge holders and are less likely to reveal the depth of their knowledge and practices. Less participatory methods have minimum engagement with ILP and can cause bias in knowledge development (Chanza and de Wit, 2013). Instead, more participatory methods (e.g., participatory action research, anthropological methods, community meetings, participatory mapping techniques, participatory forest monitoring, visual methods and living laboratories) create more space for active interactions with communities. In addition, the existence of a wide range of methods used by scholars of indigenous mitigation knowledge suggests fluidity in the deployment of such methods. It also suggests the lack of standard methods that can be used to draw from the knowledge of ILP. However, if methodologies of working with ILP are more fluid, this may present a challenge in using weak methodologies and unethical conduct by researchers who are not sensitive to the interest and rights of the people (Fernandez-Llamazares et al., 2017). To address this challenge, we argue that researchers need to use emancipatory and participatory methods that recognise indigenous people as legitimate contributors to the knowledge of climate change mitigation. Their input should also inform the design of mitigation projects. Our observation corroborate earlier arguments that methodologies for studying ILK in climate change science should not be exploitative, exclusive and unethical (Chanza and de Wit, 2013; Brugnach et al., 2017). Instead, legitimate involvement of indigenous people in mitigation projects should be an ethical requirement set to empower the concerned communities (Brugnach et al., 2017; Hausner et al., 2020). Chanza and de Wit (2013) warn that poorly developed epistemologies and methodologies can entrench the subjugation of indigenous people as their knowledge may not sufficiently perforate the boundaries set by Western worldviews, especially in climate science. Such approach limits knowledge acquisition and knowledge development, and therefore, subjugates the development of the knowledge holders and their communities. The only challenge is that the lengthy period of engagement with ILP used in participatory studies or in the design of mitigation projects may not match with limited timeframes set by research organisations and aid institutions to develop knowledge for project interventions. However, many researchers maintain that tapping from the knowledge and experiences of indigenous people is an emancipatory and decolonial agenda of making the views of people affected by climate change matter in decision processes (Eitzel et al., 2020; Gay-Antaki, 2022).

There are also many ways in which ILP are participating in climate mitigation projects, for example, ranging from CSA techniques, climate smart forestry, protection of sacred sites and ecosystems that act as carbon sinks. The ILP also act as environmental managers through the application of customary and traditional conservation practices that preserve forestry resources and other ecosystems. This role is quite useful in promoting sustainable climate change mitigation projects at the community level. We have found out that as farmers, ILP employ a range of CSA practices that help in both sequestration of carbon and minimising carbon emissions. There is potential to promote these practices and realise more mitigation benefits if they get recognised in projects that mainstream livelihoods of traditional farmers in climate change responses. However, the pressure to develop mitigation projects to meet the set global emission reduction targets may lead to hurriedly designed projects that lack local input. This may keep entrenching the poverty and marginalisation of indigenous people, challenges that need to be addressed to ensure successful projects (Ramos-Castillo et al., 2017). Concern has been raised that projects implemented by non-indigenous people to mitigate climate change may adversely affect their livelihoods and infringe their rights to land and natural resources (Jones et al., 2014; Ramos-Castillo et al., 2017). Experience with some REDD+ projects and other ecosystem management interventions has shown that success of these projects is influenced by how well indigenous and local stakeholders are identified and brought into the design and management processes (Cromberg et al., 2014; Bong et al., 2016). Despite this evidence, there are only a few REDD+ projects that explicitly specify the intention to engage with indigenous peoples and local communities (Vierros, 2017).

Instead of viewing ILP as engaging in activities that drive deforestation and other unsustainable land use practices, we support the argument that they should be seen as part of the solutions to forest loss (Vierros, 2017; Negi et al., 2018). Some studies have shown that indigenous communities’ systems of enforcing environmental laws are more effective than those used by government agencies (Chanza and Musakwa, 2021b). In this study, we found some cases in which working with indigenous people does not only serve mitigation priorities but also intersect with poverty management and livelihoods objectives (Chhatre and Agrawal, 2009; Vierros, 2017; Mahalwal and Kabra, 2023). The resilience of some indigenous practices relevant in climate change mitigation also deserves attention. There is evidence that even as deforestation has affected some landscapes, sacred sites have demonstrated remarkable resilience in the face of change and environmental degradation (Reynolds et al., 2017; Negi et al., 2018). This suggests that there is potential by climate change mitigation practitioners to harness such proven experiences towards advancing the goals of climate change mitigation. This justifies the need to tap from ILK contributing to GHG emission reduction targets, the agenda pursued by global climate change mitigation frameworks such as the NDC set by the Paris Agreement.

Our study also sought to identify the direction taken by the ILK-climate change mitigation interface. We found out that ILK and climate change mitigation research is leading to collaborative outcomes between ILP and scientists. Much of this collaboration is happening at the research level and feeding into mitigation practice and policy development. This observation resonates with the views given by Ford et al. (2016), Garcia-del-Amo et al. (2020), and Kumar and Brewster (2022). An approach towards tapping from the experiences of ILP ensures that they participate as equal partners with scientists to develop hybrid knowledge for research and development. Joint research and resource monitoring processes are critical in enhancing knowledge of managing GHG sinks, including diffusing knowledge for climate responsible behaviour by communities. The latter is required to ensure success of climate response projects. If used in developing climate change mitigation interventions, collaborative approaches can lead to co-generation of knowledge and skills that are critical in addressing current challenges with climate change (Brugnach et al., 2017). Collaboration among equitable participants could even yield more benefits. Engaging local contributions could be through community-based monitoring that utilises citizen science where the people act as observers of forestry changes or forest resource monitors (Brattland et al., 2019). Some countries have also strengthened this by incorporating ILK in local decision-making processes through national legislation (Hausner et al., 2020). However, the meaningful incorporation of ILP tend to be more reported and operational in cases drawn from the developed world (Jones, 2019; Hausner et al., 2020; Hallberg-Sramek et al., 2022). Many studies reporting about collaboration initiatives in the South raise questions of ethical conduct, sufficient representations of people rights and their interests, including poverty alleviation to ensure that mitigation objectives are not foiled by limited livelihoods options (Cromberg et al., 2014; Tschirhart et al., 2016; Kunz et al., 2022; Maru et al., 2023).

The interest to work with indigenous and local people to contribute to the knowledge, practice and policy of climate mitigation continues to gather momentum across the world. This study systematically drew on scholarship that addresses the connection of ILK and mitigation of climate change. Our study was also concerned about examining how indigenous and local community viewpoints and methods are located in mitigation scholarship. From the 43 cases considered in this study, research on ILK and climate mitigation has covered most parts of the world. Much of this work has concentrated in regions where indigenous communities occupy areas with abundant forest resources and other ecosystems known to offer high potential for GHG sequestration. We have added to the emerging but fast growing knowledge on the overlaps of ILK and climate change mitigation. This intersection is evident in three main ways: (a) validation and application of concepts used to understand carbon sequestration; (b) GHG emission reduction mainly from natural resources dependent livelihoods; and (c) the application of participatory methodologies in research and the practice of climate change mitigation.

We have observed that indigenous local communities are emerging as key players in climate change mitigation largely because of their strong attachment to the environment, which is now considered to provide great potential for reducing carbon dioxide emissions through interventions to reduce deforestation, planting trees and monitor quality of forest lands. We also found an assortment of methods used for engaging indigenous and local contributors of mitigation knowledge, from less participatory techniques to more participatory methods that recognise ILP as legitimate collaborators of climate mitigation research and practice. While some emphasis has been given on participatory methods of understanding what ILP can do to manage climate change, the same emphasis has not been widely embraced in the implementation of mitigation projects. This is particularly so in the developing world where there appears to be more attention towards promoting projects that mitigate climate change in areas inhabited by indigenous communities. To avoid creating a burden on vulnerable indigenous communities, we have recommended for the deployment of effective participatory methods that are ethical, emancipatory and empowering when collaborating with ILP. This will give clear directions towards development of effective mitigation projects that are sensitive to indigenous and local people’s needs, rights and livelihoods priorities.

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

NC: Conceptualization, Methodology, Writing – original draft. WM: Writing – review & editing. CK: Writing – review & editing.