Intensification of climate change mitigation and adaptation actions through wetland conservation: the case of Ethiopian freshwater wetlands

ABSTRACT

Over recent years, Ethiopia has massively engaged in climate change mitigation and adaptation activities so as to reduce the adverse risks of climate change. However, considering the country’s vulnerability, the effort is not diversified and nature-based solutions such as wetland conservation are overlooked. Therefore, the purpose of this review is to assess and evaluate the potential of Ethiopian wetlands as another huge on hand natural solutions in intensifying climate actions, conservation strategies, and other challenges. Recent studies on Ethiopian wetlands have shown a tremendous capacity in capturing and securing atmospheric carbon, however, their conservation is not attracting sufficient attention yet. These ecosystems’ carbon reserve potential and the ultimate role they are playing in regional as well as a global contribution is not well perceived, thereon, overlooked in the nationwide conservation activities to foster climate change adaptation. Hence, we would like to suggest that considering the coverage and potential of our wetlands it should be the go-getting time now to include them in the country’s climate adaptation actions and diversify the efforts through approaches like community-based wetland management.

KEYWORDS:

• Adaptation
• climate change
• conservation
• mitigation
• wetland

1. Introduction

Wetlands provide immense ecosystem services to humankind including the long-term containment of carbon. (Jones, 2002; Bernal, 2008; Eid & Shaltout, 2013; Evans et al., 2014; Villa, 2014). Although these ecosystems cover only about 5–8% of the earth’s surface (Mitsch and Gosselink, 2015), they play a key role in biogeochemical cycles especially sinks for carbon (Junk et al., 2013).

Carbon is sequestered in wetlands when carbon inputs tend to surpass carbon outputs (Roshan et al., 2009; Villa & Mitsch, 2015). In this regard, intact wetlands play a key role as significant sinks for organic carbon, counteracting the effects of the increase in atmospheric CO₂ (Junk et al., 2013). In contrast, when these precious ecosystems get shrunk and loss their intactness at the same time their potential of sequestering carbon is abated to huge extent (Ramsar Convention, 2002). Therefore, conserving of wetlands could help to gain triple benefits; reducing existing and avoiding future carbon emissions, building the resilience of ecosystem services (Alliance for Global Water Adaptation (AGWA) and Wetlands International Report, 2020).

Wetlands in Ethiopia are estimated to cover approximately 2% (Abebe & Gheb, 2003) covering a wide range of areas and locations (Bekele, 2010). These ecosystems provide enormous ecosystem services. . However, they are prone and thoroughgoing to degradation (EWNRA, 2005; Tessema et al., 2013). Especially, their regulatory role in climate mitigation, unlike forests, is underestimated.

Ethiopia is already experiencing the effects of climate change, showing the necessity and opportunity to intensify other new and sustainable adaptation and Mitigation techniques (Ethiopia's Climate-Resilient Green Economy; Green Economy Strategy, 2012).

Thus, this review is aimed to explore the potential of wetlands as another huge on hand natural solution in our climate change mitigation efforts, conservation strategies to attain this, and the associated challenges. An effort was made to organize this review based on the available sources.

2. Wetlands of Ethiopia and their Carbon Storage Potential

Research trend

Not on carbon dynamics of wetlands, the overall research trend on Ethiopian wetlands can be generally summed up as unsatisfactory. Even the existing research works so far are out rightly restricted to specified areas as vast of the wetland areas remain undiscovered.

Recently, it was tried in some studies to show only the glimpse of the potential of the carbon reserve of Ethiopian wetlands (Worku, 2014; Tesfau et al., 2016; Yohannes, 2013), it wouldn’t be an exaggeration to say that the soil profile of our wetlands is almost untouched by the scientific community and yet it remains secret to the scientific community as well as decision and policy makers which thus is leaving void for an appropriate conservation measure to be taken.

Meanwhile, appreciating the precedent initiations recently, their carbon accumulation potential and their ultimate role in climate change mitigation is yet not extrapolated so as to disseminate appropriate information for measures to be taken as their degradation remains escalating. Therefore, this review is done based on these few available findings.

Soil and Aboveground Biomass Carbon Profile

Despite their less coverage of the freshwater surface, wetlands are estimated to account for one-third of the world’s organic soil carbon pool (Lal, 2008) and this organic carbon sequestration in soils is a potential tool for reducing greenhouse gas (GHG) emissions (Piccolo, 2012). Besides, these wetlands also capture a significant amount of carbon di oxide from the atmosphere through their biomass (Jones & Humphries, 2002; Villa, 2014).

According to recent studies, Ethiopian freshwater wetlands are found to sequester significant amount of carbon. For instance, in the study done by (Tesfau et al., 2016) at shore wetlands of Lake Zwai, Yohannes (2013) and Worku (2014) in their study at Tekuma and Fogera wetlands of Lake Tana basin, respectively, reported the significant accumulation of soil and aboveground biomass carbon when less impact is exerted and the intactness of the wetlands is preserved. Up to a maximum of 2066.2 g C m⁻² and 67.5 g C Kg⁻¹ was recorded in the aboveground biomass and soil of least impacted wetlands, respectively. This report was found to be as high as other studies made on temperate and tropical wetlands around the globe (Barbera et al., 2015; Bernal, 2008; Bernal and Mitsch, 2013; Muniz et al., 2014; Saunders et al., 2014). This can tell us the significance of Ethiopian wetlands in capturing and storing of carbon if the level of disturbance is minimized.

Nevertheless, as discussed in the next section, land use modification such as converting them in to grazing and cultivable land by draining and clearing the wetland biomass has been reported as having negative impacts by these studies. Such activities are in turn leading to the loss of the abovementioned stored carbon in to the atmosphere. Up to around 50% loss of carbon was reported. So, draining wetlands will not only non-functionalize the wetland’s capacity to capture and secure carbon from the atmosphere but also make the wetland to loss the carbon that had been sequestered for long period of time with in it in to the atmosphere. Hence, if it can be invested on the management of these precious ecosystems it is going to be a go for dual at once and if not the reverse will be a trade-off.

3. Shrinkage and its Implication on Carbon Accumulation

Human-induced land use modification

Land use change, particularly conversion to agricultural ecosystems, depletes the carbon stock of wetlands (Ali et al., 2006; Piccolo, 2012). So, large mitigation potential lies in improved agricultural management: improved grazing land management and the restoration of cultivated organic soils and degraded lands (EUCCP, 2010). Ethiopian wetlands are under intensive pressure (knowingly and unknowingly) both by the direct and indirect interventions and are under spontaneous modification mainly through rural development like cultivation, overgrazing, and over exploitation of vegetation in which its effect on the carbon flux in the wetlands is undetermined. (Piccolo, 2012) stated that cultivation significantly affects organic matter content of soil by exposing fresh topsoil to rapid surface drying and air oxidation, and then organic compounds are released to the atmosphere as a result of the biotic and abiotic degradation. Not only cultivation, but also intense grazing has impacts of reducing vegetation cover, reducing plant residues entering on the soil and reducing the dynamics of soil organic matter (Asgharnezhad et al., 2013).

Generally, total carbon emissions from the conversion wetlands to agricultural land is estimated to range between 0.05 and 0.11 Gt C yr⁻¹(Maltby & Immirzy, 1993). Perhaps this could be because of the disturbance of the natural state of the wetland which leads to loss of the stored organic matter with in the soil (Figure 1). Taking this in to account, it can be recapped that a significant amount of carbon might be released from Ethiopian wetlands to the atmosphere as the pressure of converting wetlands is at high rate as reported in many land use/cover modification studies. So, maintaining the natural character of these ecosystems would be the best choice so as not to release out the stored carbon.

Figure 1. Schematic view of the role of wetlands in the environment at different conditions (Mitra et al., 2003).

Ethiopian wetland’s plants are commonly used for a variety of purposes from crafts making to local medicine. However, the use of these resources is not often based on a studied assessment and their sustainability is under a serious threat. It is reported that unsustainable removal of wetland vegetation will reduce the carbon sequestration potential of the wetland, and potentially release long term detritus-based carbon stores through aerobic carbon sequestrated in the sediment (Saunders et al., 2007), and also removal of vegetation cover could lead to the removal of soil organic materials through erosion (Itanna et al., 2011). Thus, better management of the vegetation cover of our wetlands is needed so as to enhance the carbon storage capacity of the soil in addition to the capture of atmospheric carbon dioxide by the plants themselves.

Impact of climate change

Ethiopia is more vulnerable to the adverse impact of climate change as the large part of the country is dry sub-humid, semi-arid and arid (NAPA report, 2007). According to recent metrological reports, a warning trend in annual temperature was recorded over the past half century. Together with unpredictable rainfall variability, it has been forecasted the worst scenario to happen in the upcoming decades (Abebe, 2017).

In Ethiopia, failed rains and droughts occur variably in time and space and recently this have been worsened by the 2015 El Niño (Sintayehu et al., 2017), which in itself has been aggravated by climate change (Oxfam Ethiopia report, 2016). During such disturbances, wetlands are one of the highly affected areas by the changing climate and are the first group of ecosystems to experience the impacts (Mitsch et al., 2010). Thus, wetlands in Ethiopia have been hit due to the shortage of rainfall caused by El Niño. If rainfall does not come on time, if droughts are prolonged, if temperature increases highly over time, if water table drops, wetlands will dry out and the stored carbon will release back to the atmosphere by oxidation and other processes.

4. Conservation for Mitigation: Community-Based Participatory Wetland Management Approach as Game Changer

It is not out of sight that Ethiopia’s commitment in the adaptation and mitigation efforts of the changing climate of the globe has intensified over time allocating a large proportion of human and monetary resources by itself as well as from aid programmes (NAPA, 2007; EPA, 2012; Irish Aid, 2017). As the country is experiencing the effect of climate change for long, it has adopted a climate resilient green economy policy and every year billions of indigenous seedlings are planted in the pains to relieve from the adverse effects of climate change. For instance, in the year 2019, under the green print campaign, around 4 billion seedlings were planted countrywide and in 2020 the green legacy upgraded and the campaign of planting and foresting an own record of 5 billion seedlings has already started officially. The country has also created spaces for NGOs and community engagement in sustainable forest management through participatory forest management (PFM) practices (Dawit and Simane (2017); Mengist & Alemu, 2019; EPA, 2012).

In spite of all this, the actions that have been taken so far can be magnificent but a long way far from being adequate and it should be the go-getting time now to further explore and act on other existing nature-based solutions like wetland management-based climate mitigation action. According to wetlands international report (2020) preventing massive carbon release and protection of biodiversity, protecting areas from the threats of flooding and warming, and creating sustainable livelihood through supporting communities to rebuild and strengthen their wetlands are among the main reasons why any climate action should include wetlands.

Unfortunately, Ethiopian wetlands are faced with degradation at an alarming rate as their socio economic and ecological role is perhaps not fully recognized (Hailu, 2007; Tessema et al., 2013; Abraham et al., 2014). Nevertheless, things can turn around if action starts to come around. For instance, nurturing and planting wetland plants should be taken seriously (Chaudhury & Faisal, 2005; Yongyut, 2006) with in the green print campaign or any other movement as a measure in combating climate change. Here, the government has to turn things and take an initiation in mobilizing the community and all other governmental and non-governmental organizations as the way it is proceeding in forests so as to restore different wetland sites through afforestation programs. Enhancing wetland vegetation plantation programs through preparation of community nurseries for the production of indigenous species, combined with improved propagation and management is said to be relatively feasible, which don’t require much capital and can make poor farmers skillful (Chaudhury & Faisal, 2005). When wetlands become highly vegetated and protected, carbon that can be fixed by the vegetation cover is immense but also highly affects the underground store by different means (Jobbagy & Jackson, 2000).

There are some showcases in different parts of Ethiopia where the community by themselves develop rules and regulations when the government is giving less attention to these ecosystems (Wood, 2001). This is a reflection of the immense values that local communities are getting from wetlands and their interest to sustainably use them. Thus, involving them in management actions could be as much productive as we thought.

Climate change National Adaptation Program of Action (NAPA) (2007) has projected “community-based sustainable utilization of wetlands in selected parts of Ethiopia” as one of the high priority adaptation projects to address immediate needs of adaptation to climate change. However, its implementation on ground is questionable. Therefore, immediate action is mandatory and customizing the attitude of the community especially those residing around the vicinity of wetlands should be proactively mobilized.

Local community must start to perceive, in addition to their effect on global climate, the impact of wetlands on local/regional climate like serving as annual water inputs to the atmosphere through evapotranspiration and restraining the extreme local temperature of neighboring highlands (Mitra et al., 2003). Similarly in Ethiopia, although these changes can be easily detected by the community, there is still gap on the knowledge of wetlands and their climatic role (Tesfau et al., 2018), thus, creating a strong awareness on them would be a basic task so that community-based management practices could be initiated for gaining of the best services from wetlands. For instance, providing alternative livelihood options to wetland-dependent communities such as practicing bee keeping, fish farming, green house farming of horticulture products, seasonal harvest of wetland products for craft making, foraging, and construction through equipping them with the right skill and knowledge could create a strong sense of ownership (Raburu et. al., 2015), thus, stimulating the natural functioning of wetlands.

A good lesson can also be taken from Biosphere reserves, i.e.,, wetland areas which are internationally recognized within the framework of UNESCO’s Man and Biosphere (MAB) in which conservation of wetlands reconciles with sustainable use. Since Ethiopia is already a member state, different wetland sites across the country should continue to be nominated for their recognition. Such practices could safeguard wetland ecosystems and improve human livelihoods through making them resilient to climate (Fatin et al., 2016).

Research enhancement for monitoring

Many scholars stressed that, unless wetlands are preserved or maintained properly, they could exponentially switch from being net sinks of carbon to becoming sources thereby accelerating the hazard of climate change (Jones & Humphries, 2002; Junk et al., 2013; Mitra et al., 2003). In this case, it has been widely revealed that capitalization of research do have an enormous role for continuous information deleverage and monitoring to make quick interventions through development of wetland-specific policy.

Many scholars and other intended stakeholders have written and spoken again at different times that Ethiopia is encountering a massive and undetermined loss of wetlands over time and yet their management is not near from getting any prioritization. Although the lack of commitment of the government takes the large share of this, research-based advocacy for sustainable use of wetlands is not widely undertaken by the designated stakeholders. Here of, more rapid dissemination of the available information on soil, plant, water of wetlands is very relevant so as to attract the sense of GOs and NGOs so that it could drastically reduce the risk of their loss and lead to a more sustainable management plan (Tesfau et al., 2016). Wetlands in Ethiopia are being pressurized directly and indirectly by national policies such as agriculture and urbanization (Wood, 2001) seeking for wetland-specific policies to be drafted and implemented.

Such actions to be taken in countries like Ethiopia, baseline studies should be attempted on the status of wetlands appear to be primary tasks to document pertinent information for policy makers.

Conclusion

To recap, wetlands in Ethiopiado have an immense role as potential reserves of carbon. Despite this, degradation on a massive scale is occurring to these ecosystems of huge importance, and they are still not pragmatically included in the climate mitigation efforts. So, things have to be turned now and conservation activities likecommunity-based participatory wetland management must be initiated. Various researches need to be undertaken on sustainable management of these wetlands and their interaction with climate. Overall, all concerning bodies should be integrated with making the wise use of Ethiopian wetlands of the economic wealth they support and the various environmental values they provide including enhancing their ability to sequester global carbon.

Abbreviations

C	=	Carbon
EPA	=	Environmental Protection Authority
EUCCP	=	European Union Climate Change Policy
GHGs	=	Greenhouse gases
GO	=	Governmental organization
Gt	=	Giga tone
NAPA	=	National Adaptation Programme of Action
NGO	=	Non-governmental organization
MAB	=	Man and Biosphere
UNESCO	=	United Nations cultural, educational, and scientific organization
Yr	=	Year

Acknowledgments

The authors sincerely acknowledge colleagues and reviewers for their relentless and valuable comments in their efforts to make a better manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).