Integration of Ecosystem Services into the Assessment of Forest Landscape Restoration in Tropical Africa: An Exploratory Review

Abstract

Forest landscape restoration (FLR) in tropical Africa seeks to improve the ability of degraded forest to provide ecosystem services (ESs) to local communities. The purpose of this study is to present ESs that are mentioned in studies on FLR and methods that best integrate the different categories of ESs that have been identified in tropical Africa. The study followed the PRISMA 2020 statement for reporting systematic reviews. Qualitative and quantitative data were analyzed using agglomerative clustering and multiple correspondence analysis (MCA). The systematic literature review analyzes modalities of ES integration through various studies on FLR in tropical Africa. In most cases, only three of the four ES categories are mentioned, namely provisioning, regulating and supporting services. Primary production is the ES category most frequently mentioned in tropical Africa. In this region, various methods are used to restore forest landscapes (reforestation, savannah protection, agroforestry). This review shows a strong link between ESs, the ES categories, use values and methods of FLR. Therefore, integration of ESs in FLR can contribute to the understanding of how FLR impacts biodiversity, climate change mitigation. improvement of human well-being, etc.

1. Introduction

Tropical forests occupy 7% of Earth’s land surface and are distributed on three continents, including the forests of Amazonia (South America), tropical forests of Africa, and forests of Southeast Asia [1]. These forests are large reservoirs of biodiversity and provide various ecosystem services (ESs) that are crucial to the survival of local communities, the economic development of nations, and the combatting climate change [2,3]. Deforestation and degradation of tropical forests in Africa, however, are threats that reduce the capacity of these ecosystems to provide various services, thereby putting humanity at risk, especially local communities that primarily depend upon these services [4,5]. In the Congo Basin, for example, it has been reported that forests both directly and indirectly ensure the survival of nearly 100 million rural inhabitants [3,6].

In the face of different threats, the International Union for Conservation of Nature (IUCN) and the World Resources Institute (WRI) indicated that about 350 million ha could be potentially restored by 2030 at the global scale [7]. About 100 million ha of these forests are found in African countries, as determined following the African Forest Landscape Restoration Initiative (AFR100) that was officially launched during COP21 in Paris, in December 2015 (https://afr100.org/). IUCN and WRI made this global and regional determination using the map that was established by The Global Partnership on Forest and Landscape Restoration [8] (http://pdf.wri.org/world_of_opportunity_brochure_2011-09.pdf (accessed on 7 December 2015)).

Tropical Africa, a vast hot region primarily between the Tropics of Cancer (approx. 23°27′ N) and Capricorn (approx. 23°27′ S), south of the Sahara, features diverse forests and biodiversity facing strong human pressures due to the great dependence of local communities upon biological resources [9]. FLR in particular can contribute to ecosystem restoration and to the improvement of their capacity for providing benefits to local communities [10]. In various tropical countries, degraded ecosystems, while maintaining a certain resilience degree, can have their balance restored after disturbances that are due to anthropogenic factors, while rapidly developing forest cover [11]. To this end, the evaluation of FLR mechanisms appears relevant to understanding their effectiveness in maintaining and enhancing ES and their level of integration [12].

Indeed, FLR and ES are linked in the sense that the maintenance and provision of ES is an indicator for assessing restoration impacts [13,14]. This approach should corroborate the process that is defined by The Economics of Ecosystems and Biodiversity [15], which aims to consider the main ESs that are provided within a given area. This is particularly important for defining adaptive management strategies and mechanisms in the context of REDD+ process implementation. Very little is known regarding studies that have addressed the issue of integrating ESs into evaluations of different interventions, which are related to forest FLR in tropical regions [16,17,18]. Such information is required to reframe and guide national policies and strategies for the implementation of sustainable forest management and restoration of degraded lands programs [19]. Therefore, there is need to review and elucidate FLR studies that have focused upon the integration of ESs in tropical Africa [20,21].

This study attempts to answer the following questions: what are the different ESs that are mentioned in studies on different FLR methods in tropical Africa? Which of the FLR methods best integrates the different categories of ESs identified? We focused on the relationship between ESs and FLR, especially as a landscape is not restored in vain, but rather to create conditions that favor the provision of ESs for the well-being of the population (Figure 1).

The interest of this study lies in the systematic evaluation of ecosystem services (ESs) provided by different forest restoration methods in tropical Africa, filling a knowledge gap on the actual effectiveness of restoration approaches in relation to local needs. Its motivation is to show how forest restoration can directly improve human well-being by providing tangible benefits, such as food, clean water, erosion control, and intangible cultural or spiritual values, thus justifying investments in these vital practices.

2. Materials and Methods

2.1. Search and Eligibility Criteria

The methodological approach was based on the PRISMA 2020 statement (Supplementary Materials), which is an updated guideline for systematic reviews and meta-analyses [22]. This approach has been recommended by many researchers and editors for literature exclusion and inclusion criteria [23,24,25]. Figure 2 illustrates the design of the search and eligibility criteria.

It presents 1674 publications identified between 1961 and 2024, based on the keywords used individually and presented in

Table 1. Keywords used to collect scientific papers and topics considered for the review.

Keyword	Definition	Topic for the Review
Tropical region	Tropical region, located between the tropics (Cancer and Capricorn), is a hot zone with high temperatures year-round, featuring alternating wet and dry seasons, little winter, and vegetation (savanna) that varies with the length of the dry spell, despite climatic similarities to neighboring subtropical areas [1]	Tropical and subtropical Africa
Ecosystem Services (ESs)	ESs are the goods and services that people can obtain from ecosystems, directly or indirectly, to ensure their well-being [27]	ESs, use value, Provisioning, regulating, supporting, and cultural services
Forest Landscapes Restoration (FLR)	FLR is a process that aims to restore certain ecosystem functions in order to improve the well-being of the people who live in these landscapes [3].	FLR, Savannah Protection, Reforestation, agroforestry
Land Conservation (LC)	LC is the practice of protecting natural areas from development or harm to preserve resources, wildlife habitats, clean air/water, and scenic beauty for current and future generations [28].	Enclosure
Reforestation	Reforestation is another method often used to restore degraded areas by planting trees [29].	Reforestation
Agroforestry	Agroforestry is a technique, but also a science, that deals with the management of crops with trees planted in the same space [30].	Agroforestry
Assisted Natural Regeneration (ANR)	ANR is an agroforestry method that protects and manages young shoots of spontaneous trees grown from stumps or seeds in the fields, instead of uprooting them [30].	Assisted Natural Regeneration

. The metadata were mainly obtained from sources, such as Web of Science, CAB Abstracts, Google Scholar, and ResearchGate during the period from March 2023 to February 2024. These were then filtered to include only peer-reviewed publications, removing duplicates, to arrive at the final count of 998 publications”. Subsequently, three exclusion criteria were used, notably (i) all papers that do not assess FLR; (ii) all papers that do not assess ESs; (iii) all papers from outside the tropical Africa. Considering these three criteria, 958 papers were excluded. For this reason, only 40 were included for final analysis (Appendix A). Given the limited number of studies included in the final analysis, we extended our scope to encompass research conducted in subtropical regions near tropical Africa (Coasts of Morocco and Algeria, South Africa). These areas exhibit similar climatic traits to the tropics, justifying their inclusion. In both cases, the majority of low-income populations depend on the ecosystem services of restored landscapes for their survival [26]. Similarly, we considered all relevant studies, not just the most recent ones, to ensure a comprehensive overview.

2.2. Analysis Strategy

The analysis focused upon the summary of the ESs that are assessed into FLR in tropical Africa. The variables used to study the sample of 40 articles are: ESs that are cited, forest restoration methods, activities that are related to ES use, ES use values, and study location, with the subcategories of ESs. The relevant database can be found in Appendix B.

Citation frequency (CF) of ESs was determined by dividing the total number of citations for a service by the total number of citations for ecosystem services across all studies.

$$Citation Frequency \left(CF\right) ofa given service={\displaystyle \frac{Number ofES citations\times 100}{Total number ofES citations}}$$

Subsequently, to produce the related graph, this information was processed using Microsoft Excel 365 (2021). Using R 4.3.2 software [31], the ordination of the MCA (Multiple Correspondence Analysis) was performed using the factoshiny package (http://factominer.free.fr/graphs/factoshiny.html (accessed on 1 July 2023)). This was produced by analyzing similarities between different studies that considered ESs in the evaluation of FLR, as well as the different variables involved in each study (ESs, their categories and use values, FLR methods, and sub-regions of Africa). For cluster analysis, each study (Individuals on the map) was considered as a statistical sample. Then, the silhouette index was calculated using the silhouette package to determine if the data had been correctly partitioned into coherent and well-separated clusters. Generally, a silhouette scores greater than 0.5 indicates good clustering, a score below 0.25 indicates poor clustering, and a score between 0.25 and 0.5 signifies fair clustering [32].

3. Results and Discussion

3.1. Different ESs Mentioned in FLR Studies

Table 2. Analysis of Ecosystem Services (ESs) integrated into Forest Landscape Restoration (FLR) in tropical Africa.

ESs	Methods of FLR	Socio-Economic Activities/Ecological Processes Related to ESs	Use Value	Countries or Sub-Regions	References
I. PROVISIONING SERVICES
I.1. Food
Fruits	Reforestation	Harvesting of NTFP	Direct use	East Africa; Cameroon,	[38,39]
Crops (beans, coffee, bananas and others)	Agroforestry	Agriculture	Direct use	Malawi, Kenya, Niger, Burkina	[40,41,42,43]
Honey production	Agroforestry Reforestation	Beekeeping	Direct use	Burkina Faso, Kenya, Mali, Niger	[41,44,45]
Birds	Agroforestry	Hunting	Direct use	Burkina	[44]
Gum arabic	Reforestation	Harvesting of NTFP	Direct use	East Africa, Burkina Faso, Mali, Niger	[38,45]
I.2. Fiber
Timber	Savannah protection, Agroforestry, Reforestation	Logging	Direct use	Ivory Coast, Burkina Faso, Senegal, East Africa, Malawi	[38,40,44,45,46,47,48]
I.3. Natural medicines
Medicinal plants	Reforestation	Harvesting of NTFP	Direct use	Burkina Faso, Mali, Niger	[45]
I.4. Fuels from biomass
Firewood	Agroforestry, Reforestation	Cutting of Firewood	Direct use	Burkina Faso, Niger, Mali, East Africa, Malawi	[38,40,42,44,45]
I.5. Fresh water
Drinking water and housework	Reforestation	Water supply	Direct use	South Africa	[49]
II. REGULATING SERVICES
II.1. PESFM	Savannah protection, Reforestation	Protection of sensitive areas and erosion control	Indirect use	Burkina Faso, Senegal, East Africa, South Africa	[38,50,51,52]
II.2. Carbon storage and fixation	Reforestation, Savannah protection	Climate change mitigation	Indirect use	DRC, East Africa, Benin, Zambia, South Africa.	[28,38,53,54,55,56,57,58]
III. SUPPORTING SERVICES
III.1. Maintenance of primary productivity	Savannah protection Agroforestry Reforestation	Protection and conservation	Indirect use	Congo, Ghana, CAR, DRC, Nigéria, Senegal, Burundi, Burkina Faso, Algeria, Morocco, Ethiopia, Zambia, South Africa, Tanzania	[28,43,50,54,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76]

NTFP, Non-Timber Forest Products; PESFM, Prevention of erosion and soil fertility maintenance; DRC, Democratic Republic of Congo; CAR, Central African Republic.

illustrates the different ESs that have been considered in tropical Africa in different studies of FLR. Eight ES products were identified, of which five (food, fiber, medicinal plants, firewood, and fresh water) belong to the provisioning service, two to the regulating services: Prevention of erosion and soil fertility maintenance (PESFM) and carbon storage and fixation), and only one to the supporting service (Maintenance of primary productivity). Studies have shown that successful FLR not only restores biodiversity and carbon sequestration but also provides crucial provisioning services. Indeed, considering different ESs in tropical African, FLR allows for more effective, sustainable, and inclusive outcomes by providing a holistic view of benefits and trade-offs, ensuring social equity, long-term financial viability, and the alignment with broader development goals like climate action and poverty reduction [33]. Moreover, no cultural service was cited, notwithstanding its particular interest to local communities in tropical Africa due to their strong attachment to cultures and traditions that have been ingrained for many decades [34,35]. FLR study limited scope may lead to incomplete or ineffective outcomes, failing to address the cultural dimensions that influence human well-being and project success. Indeed, neglecting cultural ecosystem services (non-material benefits like spiritual significance, sense of place, recreation, or esthetic beauty that people derive from forests and landscapes) risks creating restoration projects that do not align with local values, potentially excluding vulnerable groups, causing conflicts, and hindering overall project effectiveness and public engagement, as mentioned by Felipe-Lucia et al. (2024) [36]. Hunt et al. (2023) report the omission of cultural services can result in missed opportunities to generate broad social benefits and secure long-term support for restoration efforts [37].

3.1.1. Provisioning Services

Provisioning services appear to be the most frequently described service among the studies that were reviewed regarding FLR in tropical Africa. These results are due to the heavy dependence of local communities upon these services to meet their daily needs [15]. Indeed, provisioning services with direct use value are tangible, directly measurable, and crucial for the livelihoods of local communities, providing essential goods that are easily linked to tangible economic benefits [13,77,78]. The immediate and visible impacts of changes in these services also make them a priority for research and assessment, even as other services like cultural or regulating services are recognized for their importance [79]. In tropical Africa, provisioning services were identified across the different FLR assessments and accounted for 43% of citations, including 20% for food, 11% for timber, 2% each for medicinal plants and Fresh water and 8% for firewood (Figure 3). The results presented by Pagiola et al. (2007); Ha et al. (2022) [80,81] in tropical Asia and Latin America reveal similar information to those from tropical Africa. These findings involved a direct human dependence on natural ecosystems for essential resources, highlighting the crucial role of FLR in providing tangible goods like food, timber, and medicine, as well as necessities like fuel and clean water. The identification of these provisioning services underscores their importance for livelihoods and well-being but also suggests a need for sustainable management to ensure their continued availability for communities [82]. This highlights the importance of balancing universal human needs with ecological limits to support communities in the long term [83].

The provision of food to local communities by restored landscapes has considerable implications for food security in tropical Africa, as is the case in other tropical areas of the world, thereby increasing the value of FLR [13]. Indeed, agroforestry and reforestation as two of the methods of FLR in Africa demonstrate their critical role in enhancing food security and nutrition by increasing food production of various items like fruits, beans, coffee, and honey, and providing supplementary foods like gum arabic and other edible non-timber forest products (NTFPs). These current findings are consistent with previous research conducted in tropical Asia and Latin America [84]. These outcomes contribute to diversifying food sources, enhancing agricultural yields through integrated systems, and bolstering the overall food system for rural communities around the globe [85]. Ultimately, other types of “food” are not directly mentioned; however, these may have gained value or increased in abundance through FLR, including edible caterpillars [86], domestic animals, bark, nuts in agroforestry systems, reforestation or fencing. These products contribute to the further well-being of local communities. Many evaluations of FLR only assess biodiversity in general, without knowing whether the restoration work that was carried out has provided food for the community in line with their expectations [54,60]

With respect to wood fiber production, the evaluation of FLR activities through reforestation and agroforestry revealed increased tree basal area resulting in enhanced timber production. Protecting savannas, integrating trees into farms through agroforestry, and re-establishing forests via reforestation all support the larger goal of forest landscape restoration, which in turn leads to more sustainable timber production [87]. A study in tropical Asia presented similar results [88]. This comprehensive approach restores ecological functionality and human well-being across landscapes by balancing the conservation of native ecosystems with productive activities, such as growing timber in specific forest areas [23]. However, in most cases in the tropics, timber harvesting in restored forests is subsequently restricted sometimes due to the significant disturbance and potential negative impacts it can have on the forest ecosystem [18], unless the forest is intended for permanent timber production. It is more the integration of non-timber forest products (provisioning services) into the FLR that is perceived as being more important for the population’s right of use, compared to timber [43,62]. The integration of non-timber forest products (NTFPs), which can include food, medicines, and materials for shelter and income, is frequently prioritized in FLR initiatives, as it is seen to be more beneficial and important for the local communities’ rights and livelihoods compared to timber extraction [89].

Regarding medicinal plants, medicinal uses of regenerated species were only noted in some countries (Burkina Faso, Mali, Niger). This suggests a potential gap in research, while other non-timber forest products are not consistently documented for their medicinal applications [89]. These findings are consistent with those found in tropical Asia, where the non-timber forest products assessed did not include medicinal resources [81,84]. This highlights a need for more comprehensive documentation of medicinal plant use across various tropical areas and among different types of forest products to gain a fuller understanding of traditional health practices and their potential for modern research [90]. The lack of these details can have an impact on the total value of the restored forest and call into question the value of the FLR [91].

Regarding the production of firewood, similar results are observed in other tropical regions like Latin America [92,93] and tropical Asia [77]. Given that poor people are dependent on restored forests for fuelwood in tropical Africa [94], integrating fuelwood (firewood) into FLR is crucial because it addresses the dependency of poor communities on restored forests for fuel [95]. This thereby increases the practical value and meaning of restoration efforts for these communities and encouraging their greater involvement and adoption of FLR initiatives in tropical Africa, as is the case in other tropical areas [96,97]. Moreover, without careful management, focusing on fuelwood for FLR can become a short-term solution that compromises the long-term health and resilience of the restored forests, as well as the well-being of the communities dependent on them [23].

For drinking water, a study was carried out on the influence of FLR through reforestation on water resources in South Africa, a subtropical area whose climate is like that of tropical regions. This study concluded that reforestation contributed to the provision of drinking water and domestic work for local communities [49]. In contrast, FLR studies in Africa and other tropical regions like Asia and Latin America do not emphasize the importance of freshwater resources as a key ES. The critical role and valuation of freshwater services are often overlooked, even though their comprehensive valuation is essential for truly understanding the total value of FLR initiatives [98,99]. However, reforestation, being a component of FLR, serves as a natural water filtration system by improving soil health and reducing pollutants, ultimately enhancing both the quantity and quality of available drinking water [100,101]. A lack of clear data on freshwater benefits can lead to underestimating FLR’s worth and allocating insufficient resources for water management, creating a mismatch between social value and actual investment, according to the Millennium Ecosystem Assessment [102]. By restoring forest cover, communities can benefit from more stable water resources, supporting their domestic needs [103].

3.1.2. Regulating Services

Few studies have assessed regulating services in the context of FLR in tropical Africa (Table 2). These services concern the PESFM (6% of citations), together with carbon storage and fixation (13% of citations). These two services accounted for 19% of citations (Figure 3). These results are in perfect alignment with those found in other tropical regions [80,90,104,105,106]. The highlighted findings on the PESFM can be explained by the functions of vegetation in intercepting rainwater, slowing runoff, and anchoring the soil with its root system, as emphasized by [107]. The effects of vegetation on rainwater interception, runoff reduction, and soil anchoring have significant consequences for tropical environments [108]. These include enhanced water infiltration, minimized soil erosion, better water quality, and improved slope stability [109]. These outcomes play a vital role in managing stormwater, averting landslides, and preserving the overall health of ecosystems in tropical regions [110]. By recognizing and harnessing the potential of vegetation in these areas, we can better protect and restore ecosystems while addressing essential water management and disaster prevention needs [111].

The findings on carbon storage also align with those found in other tropical regions, including tropical Asia [77,112,113] and Latin America [80,106]. This consistency across different studies highlights the global importance of integrating carbon stocks into forest restoration efforts, such as reforestation, agroforestry and savannah protection, and showcases the significant potential for mitigating climate change through such initiatives in tropical areas [114,115]. Furthermore, ecological forest restoration can increase soil carbon stocks and enhance the resilience of forest ecosystems in the world [116]. Increasing soil carbon can include potential trade-offs in other climate impacts, like reduced albedo in high-latitude regions [117]; the fact that restored carbon stocks often do not reach pristine levels, challenges in achieving high rates of recovery [118]; the possibility of increased greenhouse gas emissions (CO₂, CH₄, N₂O) in certain ecosystem types like wetlands [119]; and a lack of sufficient long-term data to fully understand the implications of different restoration methods and site conditions [120].

Yet, regulation of natural disasters (extended drought, wildfires), which is of great importance especially in regions near the Sahel or East African regions [121] has not been considered in the various studies focusing upon the regulating services that were valued in FLR. This trend also applies to FLR studies conducted in other tropical areas [77,112,122]. This is due to the complexity of modeling these events, limited data and monitoring capabilities, weak institutional capacity for disaster management, and the disconnection between disaster events and forest ecosystems, making it difficult to integrate them into FLR valuations [123]. These challenges are compounded by factors such as increasing population density, resource competition, political instability, and the inadequate recognition of local and traditional knowledge, all of which hinder the effective assessment of disaster impacts and the implementation of mitigation strategies [124]. The omission of natural disaster regulation (drought, wildfires) in FLR studies means that the economic and social impacts of these disasters are underestimated, leading to incomplete valuations of regulating services and potentially hindering the design of effective restoration strategies, as explained by [121]. This gap is critical for regions near the Sahel and East Africa, where these hazards significantly threaten livelihoods, agriculture, and water resources, requiring integrated management and community involvement for resilience [123]. Taking this into account can contribute to updated values of FLR [52,53].

3.1.3. Supporting Services

In tropical Africa, supporting service accounted for 38% of citations and is the most quoted (Table 2 and Figure 3). Implications of FLR on supporting services, specifically those maintaining primary production, were generally positive. Indeed, FLR enhances crucial functions like nutrient cycling and water regulation [125]. By improving soil health, increasing water infiltration, and boosting beneficial microbial activity, FLR creates a more stable foundation for primary production [126]. This is confirmed through several other studies in Latin America [92,105] and in tropical Asia [77,88]. Primary production might be seen as the sole focus in FLR in tropical areas due to the interconnectedness of this process with immediate, tangible benefits such as food security, local livelihoods, and biodiversity conservation [127]. However, the ecological restoration assessments in tropical areas may be incomplete, focusing primarily on primary production while neglecting other crucial supporting ecosystem services like soil formation, biogeochemical cycles, and the maintenance of species habitats [128]. Additionally, the complex and vast nature of tropical ecosystems, coupled with limited resources and the impact of climate change, can make comprehensive monitoring and assessment of all supporting services challenging, leading to a narrow focus on the most visible or immediately impactful aspects [129]. This involved a need for broader assessment methods in tropical ecosystem restoration to ensure a more comprehensive understanding and evaluation of its long-term success and ecological value, beyond just primary productivity [110]. Supporting services would be more involved in the added value of ecological restoration if the role of biodiversity were detailed in the restoration zone [111].

3.1.4. Cultural Services

FLR assessments in tropical Africa generally align with those in Latin America and tropical Asia [76,106]. However, qualitative and quantitative assessments of cultural services are often overlooked or underestimated in tropical Africa compared to studies in Latin America and Asia where these services are assessed in FLR [81,122]. These studies integrate cultural aspects such as traditional knowledge, community engagement, and the cultural significance of landscapes into FLR efforts to enhance human well-being and achieve local goals [81,122]. The non-integration of cultural services in tropical Africa may occur because they are undervalued, seen as less tangible, or difficult to quantify compared to provisioning, regulating or supporting services, which are economic or environmental services, leading to their exclusion in policy and planning [130]. Despite this oversight, cultural services significantly shape the habits, customs, and overall well-being of a population, influencing everything from daily practices to a society’s core values and connection to its environment [113]. Taking these cultural services into account alongside the three other services would contribute to the integration and total economic value of ESs in the FLR assessments [113]. This could add value to the FLR by increasing the potential to attract financial backers, for example [35].

3.2. Typologies of ES Integration in African FLR

Figure 4 showcases a map that categorizes the various citations examined in this literature review on tropical Africa into three distinct clusters. This suggests that there are three types of studies that incorporate ESs in FLR assessments within this region. The average global Silhouette index of 0.51 ± 0.18 signifies a higher value than the threshold for good clustering (0.5), indicating a well-defined and coherent distribution of the studies among these three groups. The first group consists mostly of studies that were conducted in Central Africa, which have integrated only primary production as an ES. The second group consists of studies that were conducted in southern Africa focusing on reforestation by integrating regulating services (carbon stock and PESFM), and provisioning services (Fresh water). The third group consists of studies that were conducted in West and East Africa, which analyzed provisioning ESs by agroforestry. Dimension 1 contrasts studies from Group 1 with those from Group 3 (and part of Group 2), accounting for 22.69% of the variance. Dimension 2 differentiates Group 2 studies from those in Groups 1 and 3 (mostly), capturing 15.16% of the information. Indeed, this detailed categorization provides a clear overview of the existing knowledge, identifies research gaps, and informs future FLR strategies in the region by highlighting different ES integrations and their geographical concentrations. In tropical areas, studies mention that detailed categorization of knowledge about ESs is crucial for effective FLR strategies because it provides a foundational understanding of local resources and the related ESs [16], identifies specific local research needs [99] and pinpoints areas with significant ES concentrations for targeted restoration efforts [85]. This approach allows for customized strategies that align with tropical biodiversity, address specific human needs, and promote sustainable management by highlighting what is known and what needs to be learned [110].

4. Conclusions

This literature review has highlighted integration of ESs in FLR-related assessments in tropical Africa. This study faced challenges with limited data due to strict criteria, even after expanding the scope to include subtropical research. It thus revealed a significant gap where FLR assessments often ignore ESs, focusing narrowly on a few services like primary production instead of a holistic view. Key issues include overly specific research focus, a disconnect between FLR’s potential and practice (often limited to reforestation), sectoral approaches to restoration, and a failure to integrate all ES categories (like provisioning, regulating, etc.), leading to unbalanced strategies and missed opportunities for effective, context-specific restoration, especially in tropical regions. To truly leverage the potential of FLR for population well-being, future research and policy initiatives should prioritize the development of comprehensive assessment frameworks that fully incorporate all ES categories. Doing so will provide the holistic understanding needed to achieve environmental sustainability and enhance community well-being across tropical African landscapes.