Madeline Mathews
Student Number: 12728306 Submission: October 1, 2020
The Examiner: Dr. Yael Artzy-Randrup The Supervisor: Sofie te Wierik MSc The Assessor: Dr. Carina Hoorn
CREATING RESILIENT
LANDSCAPES
A SOCIAL-ECOLOGICAL APPROACH TO UNCOVERING DECISIVE
FEATURES IN LAND RESTORATION IN THE SAHARA & SAHEL
ABSTRACT
With increasing climatic shocks, due to macro-scale influencers such as climate change and population growth, it is ever more important that landscapes remain resilient. The Great Green Wall for the Sahara and Sahel Initiative (GGW) is an ambitious and large-scale restoration project aimed at increasing landscape resiliency. The original concept began in the 1980s with the idea of planting a broad continuous band of trees from Senegal to Djibouti. It has since been broadened to include a wide range of social and ecological activities. However, a focus on vegetation has remained central to the narrative and continued to influence project activities. This is most evident in the continued focus of activities in introducing vegetation (i.e. trees or shrubs) within the system. A focus on vegetation has led to the exclusion of other influential features that until recently have not been explored. Features which may be a key factor in shifting ecosystem states, such as the role of water within the region.
In this review it is shown that a shift in policy approach is needed as GGW activities have not led to the expected outcomes of a greener, restored state, evidenced by the fact that only a handful of cited success stories can be found. Therefore, existing scientific knowledge and literature were analyzed to understand influential features within the social-ecological system of the GGW area. With the addition of two case study sites, in Senegal and Burkina Faso, to explore the possible heterogeneity within the GGW area and assess potential feature interactions at the micro-level.
To address these questions a list of commonly cited decisive features was compiled, which also were reflected in the SES mapping. This review showed the inherent heterogeneity existent within the GGW area and the importance of water as an influencing feature, most evidently in land-use at the local level. In addition, the importance of decisive features such as policy emphasizing a participatory approach, informal groups, and the role of management coming from actors themselves, were found to influence the success of restoration activities.
In conclusion, two major policy recommendations were made: first, being the use of land-use typologies to provide a tool for tailored policy application, so as to make room for the heterogeneity within the region. Secondly, in the adoption of a water perspective in policy with increased emphasis on soil and water conservation activities to sustain green water levels within the system.
GRAPHIC SUMMARY
The following figures provide a visual context for the GGW Area and the project path
Figure 1: GGW, BRICKS, FLEUVE path (Goffner et al., 2019)
TABLE OF CONTENTS
CHATPER 1: INTRODUCTION 1.1 Research Question CHAPTER 2: METHODS
CHAPTER 3: GEOGRAPHIC SETTING 3.1 The Sahara-Sahel Region
3.2 Macro vs. Micro Level: Historical Regime Shifts CHAPTER 4: THEORETICAL FRAMEWORK: RESILIENCE
3.1 Water Resilience
CHAPTER 5: DECISIVE FEATURES 5.1 Social-Ecological Features CHAPTER 6: SES Mapping
6.1 Tier 2 Variables 6.2 Application
6.2.1 The social-ecological system of the GGW area 6.2.2 Sub SES Pastoral: Ferlo, Senegal
6.2.3 Sub SES Agriculture: Northern Burkina Faso
CHAPTER 7: ANALYSIS & RESULTS CHAPTER 8: DISCUSSION: NARRATIVES CHAPTER 9: CONCLUSION
Operationalization:
Land Restoration The process of regaining ecological functionality of degraded land, thus reinstalling ecosystem goods and services (UNCCD, 2020).
Desertification Desertification means land degradation in arid, semi-arid, and dry sub-humid areas resulting from various factors, including climatic variations and human activities (Goffner et al., 2019).
Resilience The capacity of a social-ecological system to absorb disturbance, adapt or transform in the face of change, so that the function, structure, and feedbacks of the system continue to support human and environmental well-being (Folk et al., 2010; 2016; Goffner et al., 2019).
Social-Ecological Systems (SES)
A geographically explicit unit that can be distinguished by its specific set of environmental and social components, the combination of which creates distinct patterns of human resource interactions (Ostrom, 2009).
Decisive Features Any property that is influencing change of or within the system with respect to restoration
Green Water Green water is the return flow of water to the atmosphere as evapotranspiration (ET) which included a productive part as transpiration (T) and a non-productive part as direct evaporation (Es) from the soil, lakes, ponded areas and from water intercepted by canopy surfaces (Rockstrom, 1999).
Terms & Acronyms:
• Great Green Wall of the Sahara and the Sahel Initiative (GGW) • Food and Agriculture Organization (FAO)
• United Nations Development Programme (UNDP) • The United Nations (UN)
• Social-Ecological Systems (SESs)
• United Nations Convention to Combat Desertification (UNCCD) • Sustainable Development Goals (SDGs)
• Major Strategic Axes (MSA)
• Sustainable Land Management (SLM) • Sea Surface Temperatures (SSTs) • National Farmers’ Union (FNGN)
1.0 INTRODUCTION
The Great Green Wall for the Sahara and the Sahel Initiative (GGW), as shown in figure 1 and figure 2, is a large-scale restoration effort, covering over 780 million hectares of land (FAO, 2016; UNCCD, 2020). The GGW is not situated in the desert as it may sound, but is active through a 21+ list of countries, with an approximate 500 million inhabitants (FAO, 2016; UNCCD, 2020). The Sahara and Sahel region have become increasingly vulnerable to climatic shocks and historically characterized by multi-dimensional poverty (Goffner et al., 2019; UNDP, 2016;). Therefore, the GGW initiative is aimed at restoring degraded lands with the end goal of creating more resilient communities to the effects of climate change.
The original concept of planting a broad continuous band of trees from Senegal to Djibouti began in the 1980’s, however real traction for the project did not take place until the early 2000’s (Goffner et al., 2019). The narrative surrounding the GGW initiative is dynamic and has evolved since its inception, however project activities have remained centered around the concept of vegetation as the main point of entry to influence and insight system change, as seen in Table 1 which demonstrates that the majority efforts are still focused on forestry and agriculture activities in the form of planting trees. This vegetation centered narrative that surrounds the GGW has possibly led to the exclusion of alternative influencing factors, most notably the relationship between forest and water (O’Connor and Ford, 2014).
This is coupled by the fact that an estimated 4% of all initial plans have been realized with slower progress than expected in shifting land degradation (UNCCD, 2020). As stated by Reij, a sustainable land management specialist: “if all the trees that had been planted in the Sahara since the early 1980s had survived it would look like Amazonia (Morrison, 2016).” With the current state of the land nowhere near to the looks of Amazonia, and with estimates from field studies, it has been found that roughly 80 percent of all tree saplings that have been planted within the region have died (Morrison, 2016; Wade et al., 2017).
Major Projects and their Soil Land Management Activities
Project Name Countries SLM Activities
Forestry & Agriculture Water
Conservation Soil Restoration BRIDGES Eritrea; Mauritania;
Sudan 5,000,000 produced seedlings no water activities 50,000 ha SWAP Burkina Faso; Chad;
Ethiopia; Mali; Mauritania; Niger; Nigeria; Senegal; Sudan
120,547 ha reforestation 4,600 ha 221,551 ha
Tree Aid Burkina Faso; Ethiopia; Mali; Niger
1.2 million trees planted 2,000 ha 29,580 ha
SOS Sahel Burkina Faso; Chad;
Mali; Senegal 2 million trees planted over 10,845 ha 7,378 ha 10,143 ha
Aggregated impact of wider GGW-related activities
GGW area 132,277 ha with
3,200,000 trees planted 7,378 ha 201,274 ha
Although project activities have had less than satisfactory results, the narrative surrounding the GGW remains surprisingly positive (FAO, 2016; UNCCD, 2020). This is due to the applicability of the project to almost all of the Sustainable Development Goals (SDGs) (UN, 2016) and the additional motivation to European countries due to the increased rates of migration seen from this zone (Goffner et al., 2019; O’Connor and Ford, 2014). Making it extremely relevant to the international community and leading to many actors working under the GGW umbrella as a means for funding. Most notably with the African Union, the United Nation, the Food and Agriculture Organization, and substantial funding from the World Bank and the European Union.
Due to the fact that project activities are not as successful as hoped, the initiative has again reached a turning point, where a new approach is needed to understand what is working and why, so funding can be more appropriately used (Goffner et al., 2019; USAID, 2018). Therefore it is essential that existing scientific knowledge and literature is leveraged to edit and refine current and future implemented GGW activities.
As the core goal of the GGW initiative is to restore land, it must be understood that all resources humans are dependent upon (i.e. land) exist within complex social-ecological realities, hereon referred to as Social-Ecological Systems (SESs) (Ostrom, 2009). Within the GGW area, due to its large reach, a variety of SESs exist, made up of decisive features (i.e. government, biophysical characteristics, community traditions etc.) and drivers which create different responses and often non-linear reactions. As these SES characteristics have dominating features and drivers, the same project activities applied over differing SESs may have very different results. For example, a region with more decentralized power may have stronger community systems in place
and be more prepared to take on activities at the local level than regions reliant on centralized power. Or communities with traditional ties to trees for medicinal, spiritual, or agricultural purposes may be more responsive to activities and have land more adapted to planting native tree species than communities that have historically existed without trees (Ellison and Speranza, 2020). Hence, different systems might require different policy approaches to successful ecological restoration. However, this notion of complexity has yet to transfer over to development policy and the narrative of GGW activities (Goffner et al., 2019; UNCCD, 2020).
Therefore this research works to understand the social-ecological system of the GGW area, the potential heterogeneity within the region, and influential features within the GGW, beyond that of just vegetation, that may be influencing the success or failure of projects. To do this the GGW area, must first be characterized and mapped so that policy makers and scientists can: 1) distinguish what decisive features and drivers exist within the GGW area; 2) map features and interactions in relation to macro and micro drivers to uncover potential tipping points within SESs; and finally 3) to tailor GGW restoration approaches by SES characteristics.
1.1 Research Question
This research will begin to answer research aim 1 and 2 by conducting a review of literature to distinguish decisive features at both the macro (global and regional level) and micro (landscape and local level) within the GGW area. Conclusions from this research can be used to inform GGW policy in a way that accounts for heterogeneity of SESs and can lead to specific conclusions for policy at the micro level.
The following research question will be addressed through a review of literature:
How can an understanding of social-ecological systems lead to more successful approaches in shifting ecosystem states in the Sahara/Sahel Region?
a. What does current literature point to as decisive features that exist within the GGW area?
b. How heterogenous is the GGW area? And how can mapping system features and their interactions at different scales (macro and micro) demonstrate heterogeneity within the region?
2.0 METHODS
Due to the scale of the GGW scope and the fact that land degradation is the result of multiple causative factors, it is crucial to understand the nature of the SESs that activities are being implemented. To gain an understanding of the GGW area, a detailed research approach as seen in Figure 5 was followed. First decisive features influencing land restoration that repeatedly resurface in literature regarding the GGW area were reviewed. Following this, SES components of the GGW area were descriptively mapped, with the conceptual SES framework proposed by Ostrom (2009), along with potential sub-SESs through two case studies to understand interactions at both a macro and micro level. To ensure a non-biased and comprehensive sample of literature was used, literature was systematically gathered through a defined search query of (“great green wall”) OR (“great green wall of the Sahel”) in the title, abstract and keywords, in Scopus. A total of 35 articles were returned, and all relevant literature was reviewed with some addition of articles found in alternative search methods
3.0 GEOGRAPHIC SETTING
To inform the research conducted, a comprehensive understanding of the biophysical setting of the Sahara-Sahel region is described.
3.1 The Sahara-Sahel Region
Africa has the most extensive dryland system in our world with the Sahel/Sahara region making up a large part of this. The Sahel is a transition zone away from the Sahara Desert where sharp gradients of precipitation occur, decreasing at a north south gradient, and increased vegetation (cover such as: shrublands, grasslands, tropical savanna, and forest) exist (Pausata et al., 2020). Drylands are especially vulnerable to both physical and social changes due to the challenging biophysical characteristics of the system making them extremely sensitive to human-induced water and land degradation (Falkenmark and Rockström, 2008). The Sahel region was recently identified as a global “hotspot” for effects of climate change (Diffenbaugh and Giorgi, 2012; Goffner et al., 2019; O’Connor and Ford, 2014). Suggesting that the continued ramifications of climate change, such as unpredictable rainfall and increased droughts, will likely only intensify due to the challenging biophysical environment where access to water is low and conditions for ecosystems to tip towards drought are high. These lands have evolved to be home to populations with the
knowledge to survive and thrive in such an environment, but shifts in macro-level features such as demographic growth and climate change, are leading to the increased occurrence of extreme events, challenging the resilience of these communities (Peng et al., 2020).
Although the term “drylands” lends to the notion that the lands are without water, the Sahara-Sahel drylands are actually made up of four dominating climatic zones (Nwilo et al., 2020) all with varying levels of rainfall and with quite a significant amount of water within the land historically (Falkenmark and Rockström, 2008).
These zones and annual rainfall received are below (which corresponds visually with figure 1): 1) The Saharan climate, characterized by less than 100 mm of rainfall per year (corresponds with the arid zone);
2) The Sahelian-Saharan climate, defined by annual rainfall of 100–400 mm (semi-arid zone); 3) The Sahelian-Sudanese with 400–600 mm (sub humid dry to sub humid zone); and
4) The Sudanese-Guinean climate, rainfall of 600–1,500 mm (sub-humid to humid zone) (Nwilo, 2020; The Netherlands Ministry of Foreign Affairs, 2018).
Understanding the different climatic zones is important to note, as systems are often not distinguished. However, the dynamic nature of climate systems makes stark demarcations difficult to make as regional systems can shift due to global changes in rain patterns and countries can exist within multiple climate zones.
3.2 Macro vs. Micro Level: Historical Regime Shifts
An issue of scale comes up when discussing this region, as interactions take place at multiple scales between different environmental processes (Falkenmark et al., 2019). The above section has described the regional biophysical setting (at a micro level); however it is important to note the existence and influence that macro level interactions have when combined with micro level shifts. This historically has been seen with two major regime shifts that have taken place within the region. The first, 5,500 years ago, when vegetation transitioned abruptly to desert, and the second, in 1969 to the early 1990s, when a 30-year drought began (Foley et al., 2003). These historical occurrences point to the existence of two alternative stable states that can exist for the region, that of a “green” Sahara and that of a “desert” Sahara (Hirota et al., 2011; Foley et al., 2003). Within the Sahara-Sahel region these shifts are brought on by an accumulation of slow variables (driven
Figure 1: Climatic zones (The Netherlands Ministry
by both social and ecological factors) at the micro level such as regional climatic shifts. Combined with fast variables seen at the macro level such as land degradation, altered solar radiation, and a change in sea surface temperatures which push the system towards a non-linear tipping point where sudden and abrupt change can occur (visualized in figure 2) (Falkenmark et al., 2019; Falkenmark and Rockström, 2008). Most importantly what this points to is the existence of multiple stable “water” states within the GGW area (Falkenmark and Rockström, 2008). Historically this was seen in large scale shifts but this also points to the existence of stable “wet” or “dry” states existing now within the region.
4.0 THEORETICAL FRAMEWORK: RESILIENCE
In recent years, the theory of resilience thinking (Folke, 2016) has been proposed as a way to approach complex systems (Davidson et al., 2016; Lade et al., 2017). Resilience thinking forces the researcher to assess systemic properties of a SES and their interactions. This approach can find leverage points for change within a system by understanding the features and drivers that are most influential for different SESs. Within the last 15 years the concept of resilience has seen a paramount increase in interest, turning the term into a “hot” topic for today’s science, with spillover into sectors such as economics and development (Lade et al., 2017). Resilience has become an interdisciplinary term, mode of research, and approach, with rich social-ecological applications in all of their aspects. Resilience at its core is about understanding complex system dynamics, and how these systems adapt and navigate the uncertainties of our reality where change is closer to a constant (Folke, 2016).
“Resilience is about cultivating the capacity to sustain development in the face of expected and surprising change and diverse pathways of development and potential thresholds between them. The evolution of resilience thinking is coupled to social-ecological systems
and a truly intertwined human-environment planet (Folke, 2016).”
Resilience was brought to the forefront of science in 1973, when the foundational research of Holling was published, defining resilience in terms of a systems ability to function, absorb, and
react to change (Folke, 2016). Today, resilience thinking and social ecological systems, often go hand in hand. As the basis of resilience thinking is focused on assessing systematic properties and component interactions, which SESs arise from. The definition of resilience used for this research is that used by Goffner et al. (2019) adapted from the work of Folke (2016), due to its direct inclusion of SESs. Resilience is hereby defined for this research as the: “capacity of a social-ecological system to absorb disturbance, adapt or transform in the face of change, so that the function, structure, and feedbacks of the system continue to support human and environmental well-being” (Goffner et al., 2019; Folke, 2016; Folk, et. al, 2010).
Most applicable to this research, is the fact that the concept of resilience has recently been adopted by international development discourse as a way to address complex challenges, such as multi-dimensional poverty. With the hope that this perspective can provide dynamic interventions that use the knowledge of systems and system interactions to drive positive change and create adaptive management responses for complex and dynamic systems (Plummer, 2010). With the inclusion of resilience in development policy, there has yet to be a clear way forward in operationalizing the concept. The GGW project provides a perfect opportunity for a large-scale, coordinated effort, aimed at operationalizing an approach to resiliency. This review attempts to begin this, by first assessing the systemic properties of a SES by mapping out main drivers seen that could be affecting different SESs, which can provide insight to leverage points for increasing systems resilience.
4.1 Water Resilience
A recent direction of resilience theory is that of water resilience, and the fundamental role that water plays within social-ecological resilience (Falkenmark et al., 2019). Water resilience refers to the ability of systems to secure water availability in the long term and that water dependent resources can function under periods of shock (Falkenmark and Rockström, 2008). Interest in this topic and terminology regarding other water sources besides that of rainfall has been necessary due to climate change induced rainfall variability and increased system disturbances such as droughts (Wierik et al., 2019).
As seen with resilience theory and its journey to significance from 1973, the introduction of green and blue water, coined in 1993 by Falkenmark and continued by research in partnership with Rockström (Rockstrom and Falknemark, 2000; Rockstrom and Falkenmark, 2010) has only recently gained attention. From this a broadened concept of water resource management has evolved to include not just runoff water resources (blue water) but also green water resources a term used to refer to soil moisture resources infiltrated from rainfall (Falkenmark and Rockström, 2008; Wierik et al., 2019). However, literature regarding water resilience and water resources, besides that of blue water, is still limited (Wierik et al., 2019). This new direction of resilience theory is extremely relevant to the GGW area due to the dependence of the region on water. Currently however a direct link between water management and GGW policy has yet to be built upon with only 4 published articles (Ellison and Speranza, 2020; Rockstrom and Falkenmark, 2010; Rockstrom and Falknemark, 2000; West et al., 2020) that explore the relationship of water sources other than that of blue water in relation to the GGW area and land restoration.
5.0 DECISIVE FEATURES 5.1 Social-Ecological Features1
The following social-ecological features were determined from the most commonly cited features that repeatedly are noted in literature as an influencing factor in regards to land restoration within the GGW area. This can point to potential “decisive features” within the Sahara-Sahel region and shed light on the current narrative that surrounds the GGW area.
5.1.1 Climate Change
Climate change to some degree is inevitable (O’Connor and Ford, 2014) and although a broad reaching phenomenon which could cause a variety of drivers, it is almost always cited as a decisive feature itself within the GGW area. The influence of climate change on desertification is still debated, however the two most accepted concepts that link climate change to desertification are that of internal feedback mechanisms, and a change in global circulation patterns due to sea-surface temperature (SST), neither of which have to be mutually exclusive (Herrmann and Hutchinson, 2005). Another point of contention is the role of mineral-dust emissions within the region and the influence this can have on incoming solar radiation, cloud properties, and atmospheric circulation (Diba et al., 2019; Herrmann and Hutchinson, 2005).
The causes of climate variability still need to be better understood; however this makes for a difficult analysis in understanding the region as the alternative explanations of desertification have very different implications and inherent assumptions when research is conducted (Herrmann and Hutchinson, 2005). With the idea of internal biophysical feedbacks between land surface and precipitation beginning research in the region in the 1970s (Herrmann and Hutchinson, 2005), and leading to the idea that land cover modification in drylands could have effects on climate. With improved monitoring abilities (i.e. satellite remote sensing and model simulations) a shift has been seen to examining external forces as an explanation for droughts, with first a focus on precipitation and now a focus on large scale circulation processes (Diba et al., 2019; Foley et al., 2003; Sacande and Berrahmouni, 2016).
5.1.2 Rainfall
In the Sahara and Sahel, rainfall and its variability, has played a complex and also still debated role within the region. However, it is recognized as an important characteristic of the Sahelian climate and a factor of drought (Foley et al., 2003; Herrmaan and Hutchinson, 2005). Connections between rainfall and mechanisms can be established but the root cause behind rainfall patterns are less clear. The link between lower rainfall rates in the region, and an established pattern of SST anomalies can help explain climate variability and along with the connection between rainfall and drought (Herrmaan and Hutchinson, 2005). This is seen most recently in the recorded droughts experienced in the region, which began in the 1960s and persisted into the late 1990s. Where rates
1 Decisive features found have not been labeled at a certain scale or as a driver, and often they can exist through multiple-scales (global, regional, landscape, local) and exist as a driver within the system as well.
of rainfall were seen to be dramatically lower, by 25-40%, between 1968 and 1997, in comparison to the previous period of 1931 and 1960 (Foley et al., 2003).
A lack of rainfall is also commonly cited as a main limiting factor in vegetation growth within the region (Peng, 2020; Ellison, 2020). When rainfall becomes too low (under 150 mm rainfall/year), the water supply in the soils top layer is not enough to sustain vegetation (Nwillo et al., 2020). In places where rainfall is less than 100mm, tree and vegetation growth, is only possible if external water inputs (i.e. runoff from depressions, or supplemental irrigation) are used. Due to this dependency upon rainfall, and its influence on vegetation, rain is a key driver within the system.
5.1.3 Population Demographics
As stated populations are set to increase between 2.5 and 3% by 2030 (FAO, 2017; Goffner et al., 2019). Population increase is seen as a major driver within the area due to its effect on vegetation cover and increased pressures on land for survival (i.e. food, fodder, and fuelwood) (Nwilo et al., 2020). With increasing population pressures, the expansion of communities is leading to a change in land use and an increase in depletion of vegetation cover in areas where settlements are concentrated (Nwilo et al., 2020). Which can affect the critical role that vegetation plays within the region in hydrology, ecosystem services, and climate change (Radosavljevic et al., 2020). Demographic increases have led to both inter migration and migration outside of the area GGW area (Herrero, 2006).
5.1.4 Policy
Policy can act as a driver within systems as the more attention that an SES has received in policy may mean that the system is less vulnerable than other SESs (i.e. places where restoration activities have taken place historically). In addition, policy can drive where funding is headed, what is prioritized, and how it is implemented. This includes whether or not policy emphasizes a participatory approach and local knowledge from the start (such as community needs and genetic species that are best fit for the system) (Nwilo et al., 2020; Sacande and Berrahmouni, 2016). High rates of policy interaction within a country also lead to increased global connectivity.
5.1.5 Government Structure
It has been seen that countries with decentralized polices that allow regional communities and local government institutions to be strengthened are better equipped to implement project activities than those that relay on state management (Escadafal et al., 2011). This enables local structures to provide local insight to policy and gives room for farmers to experiment with traditional practices (Escadafal et al., 2011; Goffner et al., 2019).
5.1.6 Trees & Vegetation
Trees within the system can improve soil, encourage water management naturally, and increase vegetation cover with positive effects to the forest-water and land-atmosphere interactions (Ellison and Speranza, 2020). In addition trees influence social and ecological aspects of the system through the ecosystem services they generate. This can be seen in the forest biomass they produce
(fodder, fuel, fruit, gum, and other non-timber products for traditional medicine), carbon sequestration, beauty, wind protection, shade for passing animals, a home for animals, increased biodiversity (Escadafal et al., 2011). As communities are heavily dependent upon natural resources (Reenberg, 2012), it is essential that resources such as soil function optimally, which is what makes trees a driver within systems. Trees are important for this as they can enhance the macro-porosity of soil with their root structures, improving infiltration of water and movement of microbial life (Ellison and Speranza, 2020) while also increasing soil organic matter through litter deposited on the top surface of soil. For the relationship between vegetation cover and rainfall, increased vegetation (i.e. trees or shrubs) can increase atmospheric moisture flows due to the strong forest-water and land-atmosphere interactions that take place regionally (Nwilo et al., 2020). It has been seen that increased tree density appears to positively impact local precipitation rates by reinforcing mechanisms that trigger rainfall and cool the ground (Ellison and Speranza, 2020).
5.1.7 Informal Groups and Community Participation
Local participation from the start has been seen to be an essential component in project success, as mobilization around project activities can provide local insight and traditional elements microcatchemnts (Escadafal et al., 2011). However, a large part of community buy-in is dependent upon other decisive features, being government and policy, both of which can influence the structure and space that informal and local groups can operate within (Escadafal et al., 2011). The feature of informal groups and community buy-in is also a major driver due to the strengthened management practices that this can lead to. Evidence of this is seen in the success of farmer-led regeneration activities, where management is led and sustained by local farmers and practices are often focused on traditional methods of soil and water management (Morrison, 2016).
6.0 SES Mapping
The above variables are repeatedly cited in literature to provide a general understanding of the region, and narratives surrounding it. However, it is also important to take a closer look at the GGW area by mapping the general area and micro level cites through case studies in Ferlo, Senegal and Northern Burkina Faso. This can provide an understanding of the differences or similarities that may exist within the GGW area and additionally support the decisive features determined above, or point to new features missed in current literature. For SES mapping the use of a social-ecological framework seen in figure 52 (Ostrom, 2009) allowed for a non-biased and structural method in mapping the GGW area, and ensured the inclusion of system features that have been deemed relevant in SESs.
2 A larger image of the applied SES framework is provided in Annex 2
Figure 5: The SES Framework is composed of eight first level variables being (ecologically) the Resource System (RS) and the Resource
Unit System (RUs) and (socially) the governance system (GS) and the actors (A). All of these variables are than influenced by large scale forces seen in the Social, Economic and Political Setting (S) and Related Ecosystems (ECO). Tier 1 variables are composed of additional tier 2 variables (Mcginnis and Ostrom, 2014).
6.1 Tier 2 Variables
Only a selection of tier 2 variables has been explored, selected variables were based on relevance and available data. Table 2 depicts chosen variables:
Social, Economic, and Political Setting Resource System Resource Unit Governance System Actors Related Ecosystems S2: Demographic trends S3: Political stability S4: Government resource policies RS1: Sector RS2: Clarity of system boundaries RS5: Productivity of system RU2: growth or replacement rate RU3: interaction among resource units
RU7: spatial and
temporal distribution GS1: Government organization GS2: Nongovernment organizations GS3: Network structure
A1: relevant actors A2: socioeconomic
attributes
A3: history or past
experiences
A5: leadership and
entrepreneurship A6: norms A8: importance of resource A9: technologies available ECO1: Climate patterns ECO3: Flows
into and out of the system
6.2 Application
In this section a general description of the socioecological system is completed, followed by two subsystem descriptions gathered from case studies in Ferlo, Senegal and Northern Burkina Faso. These sites were chosen due to the stark differences in land-use that has evolved within these regions and to explore the relative success that Northern Burkina Faso has documented in its regreening efforts (FAO, 2019). The socioecological system of the GGW area and potential subsystems are described with first and second-tier variables in the following order: (1) general GGW area; (2) Pastoral; and (3) agriculture.
6.2.1 The Social-Ecological System of the GGW area
The actors [A1] are the members of the community engaging in agriculture and pastoral activities. With 70-92% of the Sahelian populations taking part in agriculture and pastoral livelihoods (Goffner et al., 2019; FAO, 2014), these users make up an important component of the land. [A2] Actors are faced with social and ecological insecurity and poverty making it difficult for basic needs such as nutrition, health, and education to be met (Goffner et al., 2019). [A3] Historical colonialism, development policy, and past experience with international inputs have led to different responses to restoration activities (Escadafal et al., 2011). [A5] Different levels of leadership exist within actor groups based on historical structure of government, policy, and
13 different tribe or local ethnic group dynamics. [A6] Farmers and herders have historically employed traditional farming practices and established grazing routes which have evolved from the need to survive in a challenging environment. [A8] All actors are heavily dependent upon resource functioning for survival, [A9] due to the introduction of technology more agricultural activities have been adopted in areas that historically were unable to be farmed (Reenberg, 2012).
[RS1] The RS of the GGW area is comprised of all the elements of the environment, most prominently being forest, agricultural lands, grazing lands, and water sources (Nwilo et al., 2020). [RS2] The demarcation between grazing and agricultural lands is increasingly blurred due to migration and increased agricultural activities (Herrero, 2006). [RS5] The natural system is decreasing in productivity due to a variety of drivers such as migration, over use, and management techniques leading to land degradation. [RU1] The resource unit is vegetation since an increased rate in vegetation is the target goal. However other dominating resources such as water could also be used. [RU2] The growth or replacement rate of the resource is poor. [RU3] Interaction among resource units is high with resource growth intrinsically dependent upon mechanisms that involve each other. [RU7:] Resources are spatially and temporally interconnected. [GS1] Government influence on land restoration takes places at the global, regional, national, and local level. With international governments having buy-in due to outcomes of land degradation that influence the global scale such as cross-country migration and climate change. [GS2] Nongovernment organizations are often seen at the local level in GGW policy implementation. [GS3] Network structure is most relevant in the local government and informal institutions that may exist. [ECO1] The area has been affected by climate change a direct driver of land degradation. [ECO3] The flow of rainfall into and out of the GGW area is a major driver within the region. [S2] Demographic trends have been characterized by population increases leading to the expansion of communities, a change in land-use, and a depletion of resources surrounding concentrated settlements (Nwilo et al., 2020).
6.2.2 Sub SES Pastoral: Ferlo, Senegal
The first case study comes from Ferlo, Senegal. A region in Northern Sengal where[A1] pastoralism has been adopted in Ferlo as the main source of livelihoods due to the significant water constraints experienced historically in the region. This has made herders the most prominent actor with pastoral activities providing income to families and the local provision of food through milk and meat (Adriansen, 2008). [A2] Herders are extremely vulnerable to system perturbations such as drought and land degradation making it increasingly difficult to find adequate food and water sources, comprising the health of animals and food security for dependent villages (Ndiaye, 2016). [A3] Pastoralism evolved in the region due to historically low rates of rainfall, a lack of permanent water supplies, and ecosystem vulnerability which made agriculture activities and permanent settlement difficult (Adriansen, 2008; Ndiaye, 2016). Before the drought years of the mid-1970s pastoralists were increasingly engaging in agricultural activities due to the introduction of new technologies, however during this dry period many found cultivation no longer worth it and redirected back to livestock rearing and fully pastoral activities (Adriansen, 2008). [A5] Villages have developed around boreholes that were established under French colonial administration in the 1950s to allow for more permanent settlements (Adriansen, 2008). Ferlo has been locally divided into resource management units that center around watering points creating different informal territories and clearly demarcated grazing routes. [A6] Traditional practices have remained extremely strong in the region, based on knowledge of flora, characterization of surface water and groundwater points, zoning pastures, and dynamic grazing routes mobility strategies designed to lessen the pressure of pastoral activities on the land (Adriansen, 2008). [A8] Herders and villages associated are extremely resource dependent with little connectivity and minimal ability to cultivate agriculture as an additional source of food. [A9] Some technologies have been introduced to strengthen community’s resilience in regards to agriculture, animal health and veterinary abilities.
[RS1] The resource system of Senegal is comprised of a sylvo-pastoral area which receives between 150 to 600mm of annual rainfall, characterizing it as arid (Ndiaye, 2016). Temporary pools and valleys are filled with water during the rainy season sustaining livestock throughout the year. Vegetation is largely shrub flora (often thorny) that has evolved within the context of variable rainfall (Ndiaye, 2016; Niang et al., 2014). [RS2] Historically clear boundaries existed within the region however due to large scale macro shifts such as climate change and population increase, and micro level shifts such as changing food needs and grazing routes, the need to cross over previously established boundaries has been increasing. [RS5] The resource system has been decreasing in productivity due to overgrazing and increased livestock herds leading to land degradation. [RU1] The resource unit is productive grazing land. [RU2] The growth or replacement rate of the resource is poor. [RU3] Interaction among resource units is high with resource growth intrinsically dependent upon mechanisms that involve each other. [RU7] Resources are spatially and temporally interconnected (Nigang et al., 2014).
[GS1] There has been major buy-in to GGW policy at the national government level with the former president of Senegal, Abdoulaye Wade being one of the first proponents of the Great Green Wall (Alsobrook, 2014). [GS2] With enthusiasm from the national government, a multitude of non-governmental organizations and development actors have been present within the country for GGW implementation since 2008, most prominently seen in activities focused on tree planting (Alsobrook, 2014). As of 2011, 20,234 hectares almost 2 million trees each year have been planted within the country (Alsobrook, 2014). [GS3] The government is centralized , however due to the
nature of pastoralism and the lack of connectivity, historically pastoral communities have been able to manage resources in their own way based on traditional adaptive strategies, with some influence from French colonialism in the construction of boreholes. [GS4] However recently with decentralization policies and the strengthening of local institutions effects are taking place to the way in which pastoral societies have historically functioned (FAO, 2012).
Fig. 7: SES Ferlo, Senegal
Fig. 8 (right): Mapped system interactions in
6.2.3 Sub SES Agriculture: Northern Burkina Faso (Central Plateau)
Characterized by an annual rainfall of 600 to 800 mm a year, Northern Burkina Faso has historically been a suitable region for agricultural activities (Lenhardt et al., 2014; Thor et al., 2020). [A1] Farmers are the main actors in the Central Plateau with the region dominated by rain-fed farming characterized as small-scale (less than five hectares) or subsistence (Lenhardt et al., 2014; Zida, 2018). [A2] Farmers are extremely vulnerable and must operate within challenging biophysical characteristics, most notably dealing with rainfall variability which leads to disruptions in plant-growth cycles (Lenhardt et al., 2014). The country has seen one of the world’s highest population growth rates, leading to significant pressure on the limited resources available and high rates of migration. [A3] The region has experienced development interventions aimed at increasing agriculture outputs with GGW policy since the mid-1990s, with a focus on soil and water conservation projects (Lenhardt, 2014; Thor et al., 2020). [A5] The Mossi are the main ethnic group, historically known for practicing agriculture in challenging soils (Thor et al., 2020) and have thus adopted strong traditional methods of farming in the region. [A6] Farmers have established a norm of testing water and soil focused agricultural practices and disseminating results in a group manner to build off of ideas, practices, and come to successful methods. [A8] Communities depend upon the land for survival, and the success of agriculture for food security. This dependence has driven agriculture and farming methods into the center of daily lives. [A9] Technology has not been available therefore traditional methods are relied upon and farmers have adapted a range of techniques to help restore the land and with a focus on keeping water within the system during dry periods. This is most notably seen in soil-permeable dams, contour stone bunds, Zai, and demi-lunes (or half-moons) (Zida, 2018).
[RS1] The resource system of Northern Burkina Faso is semi -arid and drought-prone, with the Central Plateau located in a transition zone between the Sahel and Sudano-Sahel climate zones (Thor et al., 2020). The land is characterized by drylands made up of woody savanna or thorny acacia and seasonal rainfall that allows for rain-fed agriculture (Thor et al., 2020). [RS2] System boundaries are not clear, with resources being used for a mix of agriculture, pastoralism, and dry-season gardening, all of which depend upon the functioning of resources that overlap and share boundaries within the system. [RS5]: The system has always been challenging, with productivity seeing a marked decrease in the 1970s to 1985 due to increased pressure on the land because of population growth, and the dry period experienced regionally which led to increased land degradation, with lowered fertility and crop outputs (Lenhardt et al., 2014; World Bank, 2017). However recently the resource system has seen an unprecedented turn in events, with a rise in crop production increasing by 82% in comparison to levels recorded in the 1990s and evidence of regreening throughout the plateau (Lenhard et al., 2014; Thor et al., 2020). [RU1] The resource unit here are crops. [RU2] The growth or replacement rate of the resource is increasing. [RU3] Interaction among resource units is high with resource growth intrinsically dependent upon mechanisms that involve each other. [RU7] Resources are spatially and temporally interconnected.
[GS1] In parallel, the government of Burkina Faso encouraged NGOs to intervene and support villages in the northern parts of the Central Plateau since it was one of the poorest regions in the country (Zida, 2018). [GS2] Nongovernment organizations played an important role in supporting the diffusion of local techniques but due to the strength of the SSA network within the region, and the focus of a participatory approach local and traditional methods already tested were focused on and NGO’s served as a way to support these on a larger scale. [GS3] Burkina Faso also has one of the most active cavity society networks in SSA, much of which is focused on agriculture
with strong farmer groups existing within the region allowing for successful dissemination of information between communities (Lenhardt et al., 2014). The National Farmers’ Union (FNGN) within Burkina Faso has over 300,000 members spread across 1,200 villages and is based within the Central Plateau Region making it particularly active in Northern Burkina Faso (Lenhardt et al., 2014).
Fig. 9: Potential interactions and feedbacks
between system components in Northern Burkina Faso
Fig. 10 (right): Mapped system
7.0 ANALSYSIS & RESULTS
A list of commonly cited decisive features found in the GGW were completed through a comprehensive literature review (4.2), features that were also reflected within the SES mapping (5.0). Through the qualitative description completed at the macro and micro SES-level heterogeneity was found within the GGW area, with decisive features such as rainfall, government structure, and community participation having very different characteristics (5.2). Feature characteristics were explored for both sites (see fig. 8 and 9) and potential interactions (see fig. 10) in regards to land restoration activities.
One of the largest features that was found to drive heterogeneity within the GGW area was that of water within the system, and the different states of water this has led to within the drylands as a whole. This is most evidently seen in how different water states have led to different land-uses that dominate areas (i.e. pastoral or agriculture). Within the system it was also found that informal groups, community participation and policy type were decisive features in regards to land restoration activities.
At the local level, both sub-SESs were characterized with the terms “arid” and “drylands,” which can lead to the assumption of a homogenous nature between the two sites (Lenhardt et al., 2014; Ndiaye, 2016). Looking at the micro-level, the sub-SESs demonstrated the potential, through the adoption of different dominating land-use practices, of having very different water contents. In Northern Senegal, a historically drier state was seen, with less vegetation sustained, less focus on soil management with water management only through the use of bore holes, and the adoption of pastoralism as the main source of livelihoods. While in Northern Burkina Faso, a historically wet state was seen, which allowed for easier cultivation of the land, increasing vegetation and plant diversity, and building an emphasis on soil management practices. Both actors (herders and farmers) were seen to be innovative and adaptive due to the challenging biophysical characteristics they have evolved within. With strong traditional practices and management techniques to remain resilient. However due to macro-level features experienced by the system, such as climate change and population demographics, both sub-SESs have been pushed towards “drier” states leading to changes within the SESs and increased water scarcity (Falkenmark and Rockström, 2008).
Within Northern Senegal, and Burkina Faso one easy to see hypothesis of these different water states is the difference in rates of rainfall received, with Northern Senegal receiving less annual rainfall (150 to 600 mm) in comparison to that of Northern Burkina Faso (600 to 800 mm) (Lenhardt et al., 2014; Ndiaye, 2016). However, studies in Sub-Saharan Africa have shown that rainfall is not the only factor influencing water availability within SESs with the correlation between yield in crops and rainfall not actually proven (Falkenmark and Rockström, 2008). This is also supported by specific documentation in the region of Northern Burkina Faso which showed vegetation values (NDVI) that surpassed the influence of rainfall alone (Thor et al., 2020). As stated by Thor et al., (2020) values found were: “beyond what would be expected from the recovery of rainfall conditions alone and might be due to increased investment and improvements in soil and water conservation techniques.” The point of water scarcity experienced within the region is not debated, but it does remains unclear what the drivers are behind this scarcity. Exploration of these drivers must be better researched as water is an influencing factor in vegetation growth, and for land restoration to take root, there must be enough water within the system to sustain a greener state.
In both Northern Senegal and Burkina Faso continued perturbations has led to immense system change, testing the resilience of these communities. However, due to feature
characteristics, such as government structure, policy implemented, and informal groups, responses to GGW activities have been very different. In Ferlo, Senegal, a lack of support at the local level in the form of informal groups, possibly due to the more centralized government structure of Senegal or the nature of pastoralism as historically nomadic and isolated, has made it difficult to respond to change cohesively and to interact with GGW policy at a local level successfully (Adriansen, 2008; FAO, 2012). Lacking informal groups, can point to one of the reasons that GGW policy was unable to successfully gain participation of herders from the start, which can influence the adaption of GGW activities to include local traditions already in existence within the region (Alsobrook, 2014). This, combined with an emphasis on GGW policy that was focused on the original plan of planting trees only, led to trees being planted in the way of livestock herds and the management of trees not placed within the hands of herders. In addition, with the biophysical setting of Ferlo being more “dry,” for tree saplings to take root, local management of trees by the primary actor (i.e. herders) would have been necessary through soil and water conservation measures to sustain and manage tree growth. Without this, the success of project activities was limited, which alos increased the distrust and response to GGW activities within the region (Alsobrook, 2014; Ndiaye, 2016).
While in Northern Burkina Faso a different story evolved. Due to the strong farmer groups that were in existence and the participatory policy approach of GGW activities, farmer groups were able to share lessons from the field and have GGW policy support them (Lenhardt et al., 2014). Making traditional management practices that focused on soil and water conservation the main activity, and having farmers the main management point, increasing their involvement and trust. The importance of a participatory approach is noted in GGW policy and a foundational component of current activities (UNCCD, 2020) however features such as informal groups and community participation can greatly influence the ability of participation to take place and activities to insight change.
8.0 DISCUSSION
The Sahara/Sahel region grabbed the attention of the scientific community for the region’s challenging biophysical characteristics, its shifting regimes between periods of extreme drought and back to green, and the underlying positive vegetation-rainfall feedback which has been argued to have the ability to insight widespread climatic influence even at a global scale (Savenije, 1995). There have been a number of published studies regarding the diverse development initiatives implemented in the GGW area, with a Scopus search query of “great green wall” or “great green wall of the Sahel” returning a total of 35 scientific articles (Scopus search results, 2020). For the development sector, rarely do the two worlds of scientific research and policy meet, making the existence of these scientific articles extremely important to the interdisciplinary opportunity this initiative provides. As Goffner et al. (2019) puts it;
“Science can be designed to inform, test, and help navigate the GGW at all stages of the decision-making and monitoring processes.”
However, with an interdisciplinary approach it is important to understand the evolution of narratives, the pace that scientific research moves at, and the influence that this can have on interdisciplinary policy such as the GGW initiative. This influence is seen in that, GGW policy, has continued to focus on, and act on, the assumption that the Sahara-Sahel region is homogeneous
and that vegetation is the biggest point of influence within the region. Evidence of this is seen by the implementation of similar activities in different countries and regions without change in approach, most glaringly, in the initial approach that resulted in the large-scale planting of trees throughout the region (UNCCD, 2020). Contrary to what is stated in discourse, this review found evidence for a region full of heterogeneity that must be realized, and the influence of other decisive features, such as water within the system, and the forest-water feedback, that can potentially insight greater change than that of vegetation. It is therefore important to explore the reasons that regional heterogeneity and factors such as water have been largely overlooked until recently.
This lack of a water focus can be seen due to a narrative of drylands surrounding the region and the trajectory of scientific research which focused on vegetation dynamics. The term “drylands” and its universal prescription over the Sahara-Sahel system has led to over generalizations and a misconception that these lands are “dry.” When in actuality different states of water exist within the region, and most drylands are actually not that dry at all (Falkenmark and Rockström, 2008). Misconceptions regarding drylands have continued to lead to GGW policy that does not account for heterogeneity within drylands.
In addition to this, the evolution of understanding biophysical processes regarding land degradation in the Sahara and Sahel region began with the introduction of climate-change modeling which provided the ability to analyze land-use and atmospheric processes (Yu et al., 2017). This led to an emphasis on albedo, energy balance, and later vegetation-atmosphere feedback loops (Foley, 2003; Herrmaan and Hutchinson, 2005; Yu et al., 2017). In the process, a narrative was formed that almost entirely excluded the biophysical dimension of the forest-water role (and soil-water role) within the region (Ellison and Speranza, 2020). The effects of which can be seen in both the quantity of scientific articles focused on vegetation dynamics within the Sahara-Sahel region and within GGW policy where activities emphasis tree and forest cover and the positive effects vegetation can have on the region (see Table 1). A strictly land-atmosphere lens allows for the assumption that introducing trees within the system will lead to a wetter system, and misses a key mechanism of the forest-water role within the region (Ellison and Speranza, 2020).
Interdisciplinary work is becoming ever more popular, and although knowledge sharing is beneficial, and development policy should be embedded within the scientific world the GGW does paint a cautionary tale of how outdated narratives that begin an idea may evolve in the scientific community and yet still remain a main governing point in policy. Narratives have their own life, and once started, it is important to revisit and critically examine these narratives that govern the path that we go down. It is important to continue interdisciplinary work but it must be done so in a cautionary way, and in a way that continues to question original assumptions that policy may have been based on.
9.0 CONCLUSION
Reinforced feedback loops at different scales have led to vulnerability and poverty, which will likely only worsen due to the current state of land, resource dependency of the region, population growth, and climate change (Lade et al., 2017). Within the rural-agricultural landscape of the GGW area, 65% of the land is affected by degradation (FAO, 2016; UNCCD, 2016) and 70-92% of people’s livelihoods depend upon agriculture or livestock management creating a dependency upon natural resources, most notably land (soil; vegetation) and water (UNCCD, 2016). In addition to the current levels of land dependency, population rates are set to increase by roughly 2.5% to 3% within the region (FAO, 2017; Goffner et al., 2019). With increasing populations, the need for
functioning resources and the optimization of these resource ecosystem service outputs must be improved to sustain livelihoods and food provision for a growing population and to limit the trend of large-scale outmigration (Falkenmark and Rockström, 2008). This sets the scene for the relevance of GGW plans to be realized.
However, with only a small percentage of GGW plans that have been successful, an understanding of why restoration activities work or fail has remained elusive. Currently a new approach is needed as land restoration activities are not leading to the widespread change that was expected. This review, through a resilience lens, focused on creating a deeper understanding of the social-ecological system of the GGW area to see what may by decisive features within the system which can lead to more successful approaches in shifting degraded ecosystems towards a state of restored greenery.
In this literature review it was found that heterogeneity is existent within the region, as well as within what has been commonly termed drylands. This heterogeneity must be addressed in a way that makes room for the differences that exist within areas, and in a way that understands what creates these differences. Alongside the finding of heterogeneity, another main conclusion of this review is the influence that certain decisive features can have on SESs and on project outcomes. Part of what creates the heterogeneity within the GGW area, is the different features that make up the existent social-ecological systems.
This literature review found that one of the most influencing features within a system is actually that of water not vegetation, most evidently in land-use at the local level. In addition, the importance of decisive features such as policy emphasizing a participatory approach, informal groups, and the role of management coming from actors, were found to influence the success of restoration activities.
What makes this difficult is the complexity and scope of the project, therefore it has been proposed that two major shifts in policy are seen. First, in the introduction of typologies as a tool to navigate heterogeneity, and shift policy away from a “one size fits all” approach. Secondly, in the adoption of a water focus, where vegetation is still important, but mechanisms that allow vegetation to survive and flourish, such as green and blue water management are strengthened. The following major shifts in GGW policy are recommended:
1) The application of land-use typologies:
Land-use typologies can be used to organize heterogeneity within the GGW area, as dominating land-use has evolved from the biophysical setting and can also speak to climatic heterogeneities within the region. This can allow for tailored GGW policy for different land-use types. So that activities are tailored for example to a “pastoral” group and may be different than those activities implemented for an “agriculture” group. Currently typologies recommended are that of pastoral or agriculture based on the case studies reviewed, however additional typologies may be present such as mixed communities or predominately forest areas.
2) The adoption of a water perspective:
Taking a water perspective that includes both blue and green water can provide a framework for GGW policy to work within that creates a much-needed shift in narrative and policy towards an approach that is more sensitive to the intrinsic heterogeneity within the region. A strictly
land-atmosphere lens without the inclusion of the forest-water link will not insight sustainable system change. Therefore a water perspective can shift activities to incorporate water resource management practices alongside the introduction of vegetation. With special emphasis on identifying hydrological opportunities within traditional water conservation methods and understanding soil moisture dynamics in the region.
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