Main Implication: Original wetland science offers greater values to Africa's future
The findings within a very recent report by the UN Food and Agriculture Organisation do not surprise me. Assessing the results from natural capital actions, the report reveals that headwater wetlands in southern Africa were one of the categories of intervention that failed to deliver the anticipated benefits. Also not a surprise was that the cited root cause of that failure to deliver benefits was the lack of a deep understanding of the wetland functions. This most recent finding merely echoes the findings of past FAO work, and the findings from others that benefits from ecosystem services are not always realised - not least in the case of headwater wetlands. This finding comes on the back of another international organisation stating that the claimed benefits of wetlands in flood reduction have been exaggerated. These finding are very far from disclosing the full story but they are timely as they illustrate just a couple of examples of the implications of having failed to pursue evidence-based policy. In its lieu, we have a hegemonic view that wears a badge of 'best science' (to quote the WWDR) but that is prone to low performance.
These issues have been trailed in a series of articles - summarised earlier this week together with reactions from some key actors. I have again selected an image that illustrates the extent of these headwater wetlands in Central Zimbabwe - just south-east of Harare.
The best science, I would argue now as I have done for the past 20 years or more, is that there are some high storage, regulating wetlands that perform certain ecosystem functions and that there are low storage, generating wetlands that perform other ecosystem services. [It is also noted that there are also some wetlands that are insignificant relative to the landscape within which they are set.] That second set of ecosystem services are often the contrary to those of the former group. Even if they dont conform to the agenda so far of conservation organisations, they are nonetheless still ecosystem services with particular environmental and societal values. They are just not the same societal values as ascribed by the hegemons, who have constructed a distinctive and particular argument for environmental protection solely around the high storage, regulating case.
Mine is a distinctively different view from the hegemon that has said that the foundation for wetland management is the high storage, regulating case, with the recent caveat that not all may do so.
The utter paradox of all this is that the environmental and societal values of the low storage, generating wetland case can actually add up to a substantially greater set - and a substantially much stronger case - for valuing nature and incentives for managing the landscape than the current environmental monothesis. This view blows out of the water the somewhat dismissive claims by some environmentally-minded parties that if you are challenging the current environmental orthodoxy around ecosystems then it can solely be in order to make a case to drain them, to convert them or to concrete them over.
Within the science set, there is a majority of evidence towards the low storage, generating wetlands. As much as 50%, while it is 25% towards the high storage, regulating case. We cannot expect that these numbers in the scientific set necessarily reflect the proportion of wetlands performing such functions on the ground. At this stage, a main indicator is that there is virtually no recent science evidence of the high storage, regulating wetland case in Africa, whereas the low storage, generating case dominates the findings of recent studies. Conversely, the cases of the high storage, regulating wetlands are dominantly from the northern regions of North America, including the distinctive prairie pothole type, the attraction of much past scientific interest. These distributional perspectives aside, and perhaps recognising that we may never know precisely, let us assume for the purpose of onwards discussion that wetlands perform functions on the ground in the same proportion that wetland science reports the performance of those functions. It is accepted that this view will later change - in either direction.
So, let us look at the implications that stem from the current situation. I have set out the current situation in a number of previous articles, summarised in my most recent article. I am also energised to proceed to set out the implications, because of the absence of any pushback against my assessment and because of encouragement from among the wetland conservation community to challenge the received wisdom.
To keep it simple at this initial stage, let us say that there are two general categories of implications. The first set of implications relates to situations applying the hegemonic science and its associated policy approaches to all headwater wetlands, as is currently the case. This set has three sub-sets. First, this situation will be good for (that perhaps 25% of) wetlands that are high storage / regulating. In these cases, hegemonic science will actually be in tune with real-world hydrological processes. So, policies for managing these wetlands and their surrounding landscape that have evolved from the hegemony will also be in tune with nature. Anticipated benefits will accrue.
However, we can anticipate difficulties arising from those policy applications for a second sub-set, namely the neutral wetland case (that also may be 25% of headwater wetlands), among those wetlands that do not perform in line with the hegemony at any detectable level. In this case, we will see non-delivery of anticipated benefits stemming from investments that have been made in line with the hegemonic policy and science cases.
Moreso, we can anticipate very substantial problems among the third sub-set where hegemonic policy approaches have already been applied - or will be applied in the future - to (the 50% of ?) headwater wetlands that are low storage generators. Substantial problems will be created not only for the wetlands themselves but for the wider landscape, and for those anticipating benefits. Those anticipating reduced floods by interventions would actually be faced with larger floods than elsewhere. Those anticipating more sustained flows would be actually faced with shorter flow periods than elsewhere.
For the last two sub-sets, let us group them together into the 'misapplied policy' set and return to the detail further below. In an African situation, let us suggest that it is perhaps 30% of headwater wetlands across the continent that are actually subject to some active, operational landscape management decisions. So, yes, there will be a substantial effort needed to recover from 'misapplied policy' formulations in those cases. There will also be many cases in the future of misapplied policy as the hegemon is rolled out across other landscapes.
The second set of implications covers the set of opportunities around the low storage / generating case that remain undeveloped, having fallen into an as yet unexplored void in land and water management policy, arguably sidelined and squeezed out by the hegemon. The argument is that there is perhaps more than 50% of the headwater wetland landscape across the world for where appropriate land and water management policies (policies that match with underpinning science) have not yet had the potential to be pursued. Or even discussed. There should be no doubt that the land and water management policy for a low storage / generating case would be very different indeed from that of the high storage / regulating case advocated thus far. A high magnitude of difference of the two policy tracks for nature and for mankind should be expected - the wetlands are performing contrary services, and the landscape around the wetland is performing those services that have been assigned to the wetlands under the hegemon. These undeveloped opportunities are still ecosystem services with high societal values. They are just different services to those claimed so far by the environmental lobbies. Let us call these the 'alternate values, undeveloped opportunities' case.
As both types of wetlands are out there, here lies the very simple equation at the root of this. If the very large majority of headwater wetlands are high storage/ regulators then in the real world policy is currently fit for purpose, there may be a few cases of misapplied policy and there would be little scope for 'alternate values, undeveloped opportunities'. However, if a majority of headwater wetlands are low storage generators then a monumental disconnect has taken hold, as current policies are largely inappropriate and other opportunities remain unknown and unexplored, let alone are not yet being taken to benefit nature and citizens.
Myself, my own experience tells me that a majority of headwater wetlands worldwide are low storage generators. My experience of regional hydrological studies - across the UK and African regions and countries. UK hydrological practice is grounded in the evidence from its national databases. Evidence suggests to me that probably most in Africa are low storage generators - the inland valley swamps, the bolis, the dambos, the vleis. Remember, they cover 1.25 million sq km, an area equivalent to 20 African countries - or an area equivalent to that of France, Spain and Portugal combined. Covering that area themselves, they exert influence over a much wider area. Myself, I am not prepared to see science and policy in this area deliver a major and irreversible disconnect on that scale.
To introduce an alternate into wetland policy will be against a prevailing tide - a tide of finance flows towards a rather distinctive and narrow case for climate adaptation, and one that has several other schisms - around carbon and water mutualities and around effectiveness of catchment flood management interventions. It is inconceivable that we can battle the full gamut of intensifying landscape pressures - of which a changing climate is one - if fundamental misconceptions are embedded in our responses to those pressures.
It is quite a simple argument that natural capital was not advocated 20-30 years ago because it was then understood that nature's natural provisioning of water - for example in sustaining river flows - was insufficient for mankind. Especially in landscapes with seasonal climates. Flows in rivers were inadequate to support food production, and engineering interventions were needed to enable water's availability to match social need. Further, floods causing social damage were understood to be generated by the climate and the landscape, not by man. What brushed this understanding aside - without any new scientific evidence - was the introduction of a notion of uniquely good environmental services, performed at levels sufficient for sustaining mankind without need for any man-made interventions. This has grown into the case that it is now man's folly to invest in engineering when equivalent performance can be found in nature. It was the Millennium Ecosystem Assessment (MEA) that was intended to set out the new credo. Yet, that assessment is not as scientifically inclusive or rigorous as it should have been, and is unconvincing despite tens of millions of dollars spent on it. The concern is that in some critical areas the MEA put future policy for the environment ahead of historic evidence from the environment.
Because wetland restoration work has tended to be most pursued in mostly first world situations - where the agenda is on environmental recovery - it is rare for these interventions to have to demonstrate impact for citizens. So any poor and contrary performance in social and economic terms have remained hidden. Africa has a very different water agenda - it is about developments for citizens currently alive, and a population anticipated to grow by a further two billion within the next 80 years. Across Africa, landscape management cannot be so easily separated from social and economic outcomes as it is in Europe.
In this article, I have wanted to introduce the two overarching sets of implications - in general terms. I also want to go some way towards indicating further details of the implications within those two sets.
Let us begin with thumbnails of the more detailed implications within the set of 'misapplied policy' cases. These will arise on the ground where the hegemon policies are applied to wetlands whose hydrological performance is different from the hegemon's assumed science.
Downstream floodplain wetlands - those in the middle reaches of rivers, and often of crucial biodiversity - depend on floods expanding out of channel banks. In the tropics and sub-tropics, those floods are - in large part - generated by headwater wetlands. Yet, if the headwater wetlands are storing floodwaters, as the hegemon suggests - then it has to be assumed that those floodwaters are being generated by the non-wetland areas. Given this is unlikely scientifically in many cases, so practices for upland catchment management on the ground must be heading into disarray.
If trees are being planted on non-wetland areas to reduce what is assumed to be water excesses, then carbon mitigation finance and water can be working in sympathy. Otherwise, the carbon planting places wetland integrity into major jeopardy. This will be mostly northern exports of environmental damage impacting upon the lives and opportunities of southern citizens. Rather than the co-benefits that are the panacea of some within the natural capital arena, we are instead looking at an accumulation of drivers of detrimental impact.
Investments into the restoration of degraded wetlands are made in order to generate a return of reduced susceptibility to flooding downstream. In the majority of cases, such restoration is more likely to lead to enhanced flooding downstream, jeopardising lives and livelihoods downstream locally, and more widely if restoration is at a catchment scale.
The disarray will be even more evident when such disconnects are compounded by management practices intended to benefit these crucial mid-reach ecosystems. There is a difficult ecological paradox within the hegemon that is not rational - sustain the mid-reach floodplains for their ecological and socio-economic importance by sustaining their flood inflows, while managing the headwater wetlands in order to reduce flood flows downstream.
With headwater wetlands extensive in Angola, for example, new management practices are currently being proposed to enhance their flood mitigation role. If those Angolan headwater wetlands are instead behaving hydrologically as those in South Africa, Zimbabwe, Zambia and elsewhere, then there is a real risk that such vital and globally important ecosystems as the Okavango are being placed in jeopardy.
The environmental integrity of headwater wetlands is in jeopardy if efforts to manage and conserve them are grounded on a misunderstanding of their inputs and fluxes of water, and associated sediment and other loads. Wetlands and the wider landscape are under enough pressures, and their vulnerability to a wide range of pressures - each impacting on different parts of the hydrological cycle - can only realistically be assessed if the hydrology of the wetlands is understood free from distortions. It could turn out a tragic irony that those intending to reverse the degradation of wetlands have - by the means they have adopted - instead accelerated that degradation.
Agricultural development of headwater wetlands based on particular assumptions of water regime will fail in cases where the actual soil water fluxes differ from assumptions. These developments are often taken among citizens living on the edge, and so jeopardise lives and livelihoods, while also intensifying pressures on systems that are fragile if not properly managed.
Schemes (some as small-scale irrigation, or run-of river hydropower) may have been invested in downstream of wetlands on the assumption that flows are more sustained in those localities than elsewhere. In reality, those schemes are likely to be less viable in those locations than elsewhere, and thus face a high likelihood of failure.
Those implications will follow from misapplied policy. It is very much hoped that the blanket pursuit of the hegemon can be arrested so that such implications will not ensue widely. Yes, there will be a need for some recovery in those circumstances - hopefully limited - where such policies have already been applied misappropriately on the ground.
As the hegemon is rolled back, it is hoped that - instead - space is created for the set of 'Alternate values, undeveloped opportunities' to take hold across the African continent. Let me here describe what those might be.
a) Value of generated river flow to Africa's cities and towns: Under the previous model, greatest social value is flood reduction to downstream communities. Not the most severe floods - the kind that kill and devestate livelihoods - but reduction of the more mundane floods of low return period. Financial value of n billion US$. Under the 'alternate values' case, the ecosystem service of value is the generation of wet season flows. These are the flows into rivers that provide water supplies to towns and cities, that generate run-of-river electricity, enabling GDP growth of urban environments. That water has even greater values when combined with storage, extending availability into storage based hydropower and irrigation. These are flood flows in the sense of being rapid response flow - rather than as floods that devastate or cause damage. Those severe floods are generated by heavy rainfall, and the landscape - whether wetland or not - is not especially significant to the conversion of rainfall to river floods.
Under this case, degradation of upstream wetlands - and the loss of their flow generating capability - will be at the expense of the GDP growth and productivity of urban environments. Those losses would be on a regular year-by-year basis rather than the current hegemon case where benefits are claimed for occasional disaster risk reduction, perhaps once every ten or twenty years. Urban communities are far more likely to invest in water source protection, so Payment for Environmental Services can be reconfigured.
This flow generation role is especially critical in African settings where the headwater landscape is typically characterised by what is called 'green water' - an enclosed water cycle that is dominated by a rainfall, storage, evaporation cycle, mostly disconnected from river systems. Under such settings, the majority of rainfall is returned to evaporation, offering value to local vegetative growth amid the high evaporation rates. Amid these settings, it is the headwater wetlands that are critical to the evacuation of water away from the evaporation-dominated cycle into river systems and water's conversion into values for downstream human settlements. Arguably, for many African rivers, headwater wetlands are the dominant source of river water for downstream consumption, industry, power and agriculture. Detailed figures will emerge in the future, but the value of wetlands as generators must be order of magnitudes greater than any values from occasional reduction of low return period (mostly non-damaging) floods by wetlands as regulators.
This same river flow water generated by wetlands is also vital to sustaining instream ecological flow requirements - of fish, plants and invertebrates, and mammals, including spate flows that are a valuable part of life cycles.
b) Value of retained soil moisture for female-headed households: Under the high storage, regulating model, the societal value is assigned to the release of water by headwater wetlands during the dry season to downstream users. Those users could be farmers, probably elite farmers if they are able to access river flow by pumping. Under the alternate values case, the value of that same water is instead as retained soil moisture within the wetland, of value to low-level input farming on the wetland itself. By extending moisture availability into the dry season unlike other parts of the landscape, so these wetlands provide essential survival livelihoods - perhaps even small market surpluses provided levels of use do not undermine the ecological integrity. With more than half a million small headwater wetlands across Africa, many small villages have a small headwater wetland nearby. Perhaps 50-100 hectares in size, of which perhaps 5-10 hectares can be farmed at critical times that extend food availability. The cost of not exploiting this value will be measured in lives, food import bills and lost livelihood opportunities, especially for women and female-headed households.
c) Making more of groundwater: In certain situations in Africa, headwater wetlands force groundwater movement to the surface and to evapotranspiration at the wetland margin. It is this pathway that means wetlands can act to reduce dry period river flows - groundwater that would otherwise have reached the rivers downstream of the wetlands. This opens up opportunities to consider exploiting that groundwater that would otherwise be lost to evapotranspiration. This is potentially a low-cost exploitable resource - with options for gravity-fed supply for supplementary dry season irrigation adjacent to productive soils. It potentially means that some headwater wetlands could be farmed to benefit from their soil productivity but without detrimentally impacting upon the wetland water budget. This would not be the kind of low-level subsistence agriculture but could be market-based farming of high value crops - although not necessarily at intensive scales.
d) Fracture identification for rural water supply. For wetlands to be effective in storing floodwaters, the hegemon implies that the landscape above the wetlands is the generator of flood flows. In reality, movement of water across much of Africa's landscape is in fact, groundwater dominant. But unlike the large aquifers of Europe, much of Africa is characterised by Basement Complex, in which fracture zones are the primary pathways of conveyance. On Basement Complex, borehole yields are orders of magnitudes higher from boreholes that tap these fractures - to the extent that those that do not have high failure rates. With little physical surface expression of their occurrence, identifying fractures has proven a major challenge to groundwater developers, and to a source of social and economic transformation by rural citizens. However, once notions other than those of the hegemon are adopted, and that conveyance is through fractures that can in some circumstances intersect with wetland margins, then major new exploration opportunities for rural water supply are opened up. Those are opened up when the headwater wetlands provide a means for detecting the fracture occurrence. They are opportunities for drinking water, sanitation and hygiene in rural Africa, and for small productive uses in agriculture. To date, opportunities to explore such possibilities have been closed down by advocacy that has wrongly portrayed African landscape flow paths.
e) Groundwater's contribution to river flows; Under this alternate case, groundwater is recognised as the principal regulator of rivers, not wetlands. So, if catchments are to be managed for sustained baseflow (because of its import for ecology and for human benefits) then land and water management must be catchment-wide, focus on aquifers and avoid (or even reverse, where necessary) the narrow wetland-only management focus that has been advocated by the hegemon case.
f) Better calibration of global climate models: Global climate models are currently based on assumptions of wetlands as active and preferential recharge zones. This leads to corollary estimates of recharge for aquifers. However, a number of global models currently perform badly in estimating recharge. Under the alternate opportunities case, where headwater wetlands are recognised as minimal recharge areas, the higher estimates of through non-wetland zones could well lead to better model simulations.
g) More realistic water quality management: The pathways that water takes into, through and out of wetlands is important for water quantity functions. But this flows and fluxes are key to understanding water quality and associated biodiviersity functions. Opportunities to derive new understandings of fluxes and stores arise, especially in tropical landscapes.
These case are clearly ecosystem services and natural capital - but crucially they are the reverse outlook on those, with different ecological and societal values. Caution will of course be needed to avoid applying such notions to that part of the wetland landscape that act as high-storage, regulators.
There has been a tendency in recent years to promote green infrastructure alongside or instead of grey infrastructure. Bottom line is that there is no grey infrastructure that can perform similar functions to these alternate cases. Further, the societal gains from this kind of green infrastructure are maximised by storage of water - so green infrastructure is insufficient on its own. Arguably, any debate around this will evolve into green infrastructure being most effective when in combination with grey infrastructure.
Research on headwater wetlands in southern Africa in particular was originally stymied by the pervasion of colonial legislation that benefitted elites at the expense of the poor. For a brief period, from the mid-1980s to the mid-1990s original science and evidence corrected the understandings and misperceptions that stemmed from that earlier apartheid era, and witnessed a significant phase of investment into research - both physical and social sciences around the low storage / regulation case. However, that thinking was essentially closed down by the rise of the hegemon, pushed to the margins and over-ridden and rejected as controversial by new policy directions. Efforts have been made to keep that original evidence alive and in context - including a major 2003 published review - but have not gained traction. Constant calls for the hegemon to support its different policy case by scientific review have not been taken up.
Recently, there was a belief around the hegemon that alternate views jeopardised wetlands. In fact, by now framing the implications arising within an ecosystem services and natural capital framework the realisation better and stronger case for environmental management than ever before. At least one of the barriers to gaining traction is thus lowered. More investment finance has to correct the science: policy disconnect, with the rationale for returns on that investment being that long-run benefits to environment and society are higher from the alternate case than continuing along the current track. Those investments will raise the stock of headwater wetlands way above where their stock currently lies. African institutions and the engagement of individuals not acting in institutional names can be further keys to unlocking this reversal. Women will be the prime beneficiaries of this shift. It is an agenda for the next 20-50 years, so early career researchers who will continue to longer-term influence will also be important. Africa offers much more productive ground for breakthrough on this because of the much closer association between future economic benefits and environment, because in Europe the agenda is driven principally by environmental restoration with little attention now to growing the economy-wide benefits from water. Early steps can be taken to find a workable means to differentiate which wetlands on the ground are high-storage regulators and which are low storage generators.
Rather than it being the low storage / generation model that is branded controversial, as it has been, it will likely become the case within a few years time that pursuit of the hegemon alone - if it is to be continued from now onwards at all - will have become the controversial track.