Geology for Global Development

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Water and Sustainable Development – 6th GfGD Annual Conference Event Report

Water and Sustainable Development – 6th GfGD Annual Conference Event Report

Understanding, managing and protecting water resources is critical to the delivery of the UN Sustainable Development Goals (e.g., education, water and sanitation, healthy oceans, zero hunger, good health, gender equality, energy, industry, and biodiversity). Increasing urbanisation, industrialisation, and climate change, however, are increasing pressure on water supplies and reducing water quality. Our 6th Annual Conference explored the role of geoscientists in managing conflicting demands for water, ensuring that the needs of the poorest are met while enhancing the health of ecosystems. We recently published a full event report online, and here we share some of the highlights.

Our Annual Conference is a highlight for many involved in the work of Geology for Global Development, bringing together people from across the UK and beyond to explore how geoscientists can contribute to sustainable development. This year approximately 120 attendees gathered at the Geological Society of London to talk about all things water, Sustainable Development Goals and geoscience.

The conference was opened by Lord Duncan of Springbank (UK Government Minister for Scotland and Northern Ireland, and a fellow geoscientist). Lord Duncan gave a passionate description of the important links between politics, geology and sustainable development. Another distinguished guest was Benedicto Hosea, visiting the UK from Tanzania and working closely with the Tanzania Development Trust. Benedicto gave us an insight into water resources in Tanzania, and the realities of implementing projects and taking practical action to improve water provision.

Our keynote lecture was delivered by Professor Bob Kalin from the University of Strathclyde, who gave us an overview of the interactions between water, geoscience and human impacts – and why it is important that geoscientists engage in the delivery of the Sustainable Development Goals. You can find a recording of a similar talk Professor Kalin presented at a TedX event.

The first panel discussion of the day focused on management, with insight from industry, academia and the Overseas Development Institute. We discussed the challenges involved in listening to and considering many stakeholders, the management of transnational aquifers and how best to enforce policy – then attempted to come with some solutions to these challenges. Our event report includes links to key reading suggested by our panellists.

Water contamination is a significant environmental issue in many countries at all stages of development.  We heard about research into salinization and arsenic contamination of groundwater in Bangladesh. Mike Webster, head of WasteAid (check them out here) gave a different perspective on water contamination, talking about the work the charity has done in improving solid waste collection, thereby improving drainage and water quality.

Probably the most hectic, yet fun part of the conference was the UN style activity – we split up into groups representing different stakeholders and came up with a research and innovation statement relating to water and the SDGs.

We were also joined by The Eleanor Foundation, a charity working in Tanzania to provide access to safe, clean water provision to communities through pump installation and education programmes. It was so inspiring to hear about a charity that has undertaken effective work in ensuring the sustainable supply of water to communities, and made a real difference in improving lives – it is estimated that the Eleanor Foundation has improved access to water to over 250,000 people. In 2019, GfGD will be supporting the work of The Eleanor Foundation, helping to deliver SDG 6 in Tanzania. We will be using surplus income from our conference, together with other funds, to facilitate an evaluation of The Eleanor Foundation’s water programme. This will generate recommendations for The Eleanor Foundation team to ensure long-term impact and sustainability.

In true GSL conference style, we finished the conference with a reception in the library, giving us all the chance to chat about the conference and meet people sharing an interest in geoscience and development (of course admiring William Smith’s geological map!). I think it would be fair to say that a fun and interesting day was had by all, and I left feeling excited by the number of geoscientists I met that all share enthusiasm for the role that geoscientists have in helping to achieve the SDGs.

The 7th GfGD Annual Conference will be on Friday 15th November 2019, hosted again by the Geological Society of London. Please do save the date, and we hope to see you there!

Laura Hunt is a member of the GfGD Executive Team, and a PhD Student at the University of Nottingham and the British Geological Survey.

Peat in the Tropics

As has been previously discussed in Robert’s blog, fertile soil is an incredibly important resource that is fast running out in many regions of the world. It is true that soil’s importance for agriculture (and sustainable development) cannot be understated, but I wish to focus on another aspect of soil in this week’s blog– its ability to store carbon.

One soil type in particular, peat, is an incredibly important form of carbon storage. Despite only covering 3% of the Earth’s land surface it contains a third of the carbon stored in soils, formed by the build-up of partially decomposed organic carbon, trapped in waterlogged and anoxic conditions. For this reason the preservation of peatland is of the upmost importance, and should be considered in sustainable development efforts in order to prevent the release of vast amounts of carbon into the atmosphere.

Figure 1- Distribution of mires around the world. Source: International Peat Society, Available www.peatsociety.fi

When you picture peat it is typically in a cool and damp climate, such as in the highlands of Scotland or expanses of tundra within the Arctic Circle. This is because the cooler climates further impede the decomposition of organic matter and facilitate the formation of peaty soils. Recently, however, it has been discovered that peat forms in other regions too, and in quantities far vaster than had ever been considered before. These tropical peat deposits form in the swamps commonly found in the river basins of warm and humid regions. Although warm and wet conditions typically aid the processes of rot and decay, the often stagnant water of swamps produces anoxic environments not dissimilar to those in the extensive peatlands found at higher latitudes. Conditions are exacerbated by poor drainage, high rainfall and overbank flooding by rivers, meaning that the land never truly gets the opportunity to dry out and peatlands are able to form, albeit in much smaller expanses than those in the North.

Despite the smaller size of tropical peat deposits they are disproportionately more significant to sustainable development, as they tend to be focussed in regions where development is occurring rapidly – central Africa, South East Asia and South America. Building on and draining these fragile ecosystems could result in mass release of carbon dioxide.

An example of a tropical peat deposit is the Cuvette Centrale depression in the Central Congo basin, where the peat is relatively shallow (with a median depth of 2m), but has a large aerial extent, making it the greatest ranging peatland in the tropics. Other extensive peat deposits can be found in the amazon rainforest and in tropical Asia (for example the island of Borneo) but land use changes in recent years have drastically reduced the amount of peatland in SE Asia, as much has been drained for agricultural use. It is predicted that SE Asian peatland will be lost completely by 2030, but thankfully the peatlands in other areas of the world are in a significantly more pristine condition, relatively unaffected by humans due to their relative inaccessibility.

Drainage of land for agricultural use is not the only threat to tropical peatlands. Climate change is acting to reduce the annual precipitation in many tropical regions, meaning carbon trapped in peat is oxidised more readily and able to decompose. Even though tropical peatlands are only a fraction of the size of their northern, cooler cousins, they still represent huge carbon stores that, if destroyed, could accelerate the release of carbon into the atmosphere and accelerate global warming further, entering into a feedback loop which will release tonnes of carbon into the atmosphere that has lain trapped underground for millennia. Carbon stocks of peat in the Cuvette Centrale alone are potentially equal to 20 years of current fossil fuel emissions from the USA, demonstrating the importance of protecting this seemingly insignificant soil type.

Figure 3 – SE Asian rainforest. It is in rainforests such as this that peatlands are quickly being drained for agricultural use. Source: https://imaggeo.egu.eu/view/4268/

A further concern is that swamplands are a refuge for many of the world’s remaining megafaunal populations, including lowland gorillas and forest elephants. It is clear that if Africa and South American peatlands are to avoid the fate of the SE Asian counterparts, they must become a conservation research priority.  Doing this would undoubtedly help to combat the rise of CO2 levels and simultaneously work towards the UN Sustainable Development Goal 13 – climate action.

Robert Emberson: Soil Erosion and Sustainable Development

Over the last few weeks we’ve introduced you to some new faces on the GfGD blog, including Robert Emberson, Heather Britton and Jesse Zondervan. Today, Robert (based in Victoria, Canada) writes on the connections between soil erosion and sustainable development, and poses the question – is soil one of our most threatened resources? 

When we talk about sustainable energy sources, most of the time we’re referring to renewable sources of electricity and heat. Geothermal, solar, wind or waves – these are all sources of energy that are, within practical limits, not exhausted by our use. However, all living species need more than just electricity and heat as energy; we need food to sustain us.

The vast majority of food for humans requires agriculture, whether vegetable crop or grazing species. Agriculture depends completely on fertile soil to succeed, but we often don’t think about soil as a resource that really matters. Crucially, however, the rate at which soil forms is vastly outpaced by the rate it erodes away in modern farming. For all intents and purposes, soil is a non-renewable resource, like fossil fuels.

A recently published UN study has highlighted this, estimating that 24 billion tons of fertile soil is lost annually every year – primarily in sub-Saharan Africa. The implications for sustainable production of food are obvious, with some studies suggesting we only have an average of 60 years’ worth of harvests left under the current practices.

We shouldn’t ignore the inherent potential of this crisis to exacerbate existing economic inequalities, too; according to the study authors “critically unbalanced land productivity trends in African cropland and grasslands are particularly concerning given expected population growth.”  This, in fact, highlights the most worrying trend; even as soil is eroded away, and the amount of cropland dwindles, the global population increases apace, with 9 billion mouths to feed estimated by 2050.

Farming in Uganda (Source: GfGD)

Moreover, the UN study emphasises that degradation of soil and loss of agricultural land increases the competition for already-scarce resources, which could lead to mass migration or social instability, further increasing the difficulty of implementing sustainable solutions.

So how has the problem become so acute? It is useful to first explain how soil erosion occurs naturally, before thinking about how humans have impacted the natural cycles. Roughly, natural soils form as the result of chemical breakdown of underlying bedrock, supplemented by organic matter decaying from dead plants and animals. In a stable system, the rate at which soils are produced is in balance with the rate at which water washes away surface material during floods and storms.

In some parts of the world, where warm, wet, conditions are ideal for plant growth and chemical reactions, soil can grow extremely fast – as much as 2.5mm per year, although the global average is nearer to 0.1mm per year.

Water is the primary agent that erodes the soil. Whenever rain falls, droplets can dislodge material, and these can be washed away downhill or carried in floodwaters over landscape. It’s no surprise, then, that soils through which water can more easily infiltrate are less likely to lose material to overland flow. However, humans have fundamentally altered this balance.

Natural forests allow water to infiltrate into soil quickly, but without root systems and porous soil this can be much lower. For example, in Wales scientists demonstrated that forested plots had infiltration rates 67 times faster than sheep pastures. Agricultural land is similar, or can be worse; if there are no crops to bind the soil together for some parts of the year, or if ploughing churns up the soil and allows material to be easily washed away, topsoil can be severely depleted in a single flood.

These two factors – lack of plant cover, and extensive tillage – are hallmarks of high intensity farming globally, but as the UN study points out, while this kind of farming has increased productivity over the last decades, it is increasingly unsustainable. Addition of fertiliser has increased the productivity, but masked the degradation of arable land. Moreover, in some regions it creates a viscous cycle, where loss of productive land leads to deforestation to access untapped soil.

Forests are key buffers against many slow and fast moving disasters; they can limit flooding, by encouraging water to infiltrate rather than running over landscape, and in doing so can allow more water to reach aquifers – thus limiting drought later. They also serve important roles in stabilising hill-slopes against landslides, and slow desertification. Given how long it takes for forest to regrow, it seems clear that the impact of soil loss will be felt for years to come.

So what can be done to prevent it? And how can geologists act to help address the problem, particularly how we can still achieve sustainability goals in the face of the rapid loss of life-giving topsoil? An integrative approach is certainly important. Soil is the interface where life, at a microbial and macro-scale, coexists with physical and chemical processes in the bedrock. Understanding how all of these fit together is crucial to build a clearer picture of the at-risk soil.

Sustainable rehabilitation of agricultural land has been achieved at a wide scale in some countries, like Ethiopia. Surface process geologists could help by producing maps of local and regional propensity for erosion, to help guide these efforts. Scientists from the Kenya-based World Agroforestry Centre have been hard at work producing for the first time maps of soil chemistry and health across sub-Saharan Africa, and these should similarly help to more efficiently utilise the soil for particular crops, and aid in crop choice for a given location, if appropriately combined with crop biology assessments.

The authors of the UN study explain that increasing the efficiency of agriculture would certainly alleviate some of the stress on croplands. Improvements in efficacy can be found at different points throughout the food supply chain; for example, the authors write that:

“Eliminating food waste would reduce the projected need to increase the efficiency of food production by 60 per cent to meet expected demands by 2050”.

Meat uses five times as much land for a given nutritional intake than the comparable vegetable option, so reducing the intake of meat, along with other nutritionally inefficient crops (like soy and palm oil) would distinctly reduce the amount of cropland needed to feed 9 billion people. These solutions are politically sensitive, of course, but scientists can make informed decisions about their own food choices, and encourage others to do the same.

Above all, given how important soil is to land surface processes, many geologists could ask themselves which aspects of their own knowledge might help alleviate this significantly under-reported problem. While we have alternative, renewable energy sources to turn to instead of fossil fuels, we don’t yet have an alternative to soil, and as such it’s perhaps imperative to think about soil as one of our most threatened resources.

Robert Emberson is a science writer, currently based in Victoria, Canada. He can be contacted via Twitter (@RobertEmberson) or via his website (www.robertemberson.com).

**This article expresses the personal opinion of the author. These opinions may not reflect official policy positions of Geology for Global Development.**

Volcanic and Biological Hotspots

Geology for Global Development followed Professor Iain Stewart’s BBC two TV series (June 2013), ‘Rise of the Continents‘ with interest. In the first episode, Iain mentioned something that really caught our attention – the strange volcanoes along the East African rift valley and their effect on soils and wildlife. 

Each year, as the rainy season transforms the Serengeti, a nutrient hotspot emerges: a small patch of grass that is exceptionally rich in calcium and phosphorous, essential nutrients for healthy calf development. Millions of wilderbeast are born here at the end of their mothers long migration, and for a short while, this hotspot hosts the largest concentration of grazing herbivores on the planet.

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A look at the Ol Doinyo Lengai lava down the microscope, under crossed polar light, reveals some unusual minerals (combeite, nepheline, aegirine, sodalite). Source: T Peterson, Mindat. More information here.

The grass in this part of the Serengeti is unusual because it lies on soil forged by one of Africa’s most explosive volcanoes, Ol Doinyo Lengai, known to the Maassai as the ‘Mountain of God’. As Iain Stewart squeezed droplets of acid onto the lava, bubbles of carbon dioxide were released, indicating the presence of carbonate minerals. This is the world’s only active carbonatite volcano. 

The sodium and potassium carbonate minerals of the Ol Doinyo Lengai lavas are unstable at the Earth’s surface and susceptible to rapid weathering. Within a few months of erupting, lava flows turn from black into a pale powder. The resulting volcanic landscape is different from any other in the world.

To form lava with such strange properties, the rock must have melted at low temperature and high pressure. At only 500-600 degrees, carbonatites are relatively cool by lava standards. The volcano is fed by the mantle superplume that stretches out beneath the rift valley, pulling Africa apart. The red sea will one day (in the very distant future) flood this plain, splitting the region in two.

Oldoinyolengai
Ol Doinyo Lengai eruption 1966, from U.S. Geological Survey.

Ol Doinyo Lengai lies at the end of a chain of extinct volcanoes and its crater rim sits atop the products of previous eruptions. Evidence of previous activity is rife, so an eruption was never unexpected. Geologists suspected that a sudden increase in daily earth tremors felt in Kenya and Tanzania, reaching up to 6.0 on the Richter scale, were  indicative of the movement of magma through the Ol Doinyo Lengai. The volcano erupted shortly after, on September 4, 2007, sending a 5Km plume of ash and steam at least 18 kilometers downwind and covering the north and west flanks in fresh lava flows.

The eruption ruined crops and forced local residents, mainly herders, to flee with their livestock. The people living nearby are concerned that it will happen again.

The mantle plume beneath East Africa is of great environmental importance. This region of intense geological activity has resulted in problems with water contamination within the rift valley, as well as producing volcanic and seismic hazards. However, the strange nature of the carbonatite lava has created a nutrient hotspot – one that draws both animals and people into the region.

 

Recommended Reading:

Nasa have an information page on Ol Doinyo Lengai, which includes some very clear aerial photographs. 

The Ol Doinyo Lengai Website includes photographs and information on past eruptions.