Category Archives: Forests, food and farming

Underwater UK: how to stop floods by planting trees

The Thames is higher than I’ve ever seen it – seagulls swim on the football fields, my route to work is underwater, and thousands of homes face the misery of flooding.

With this kind of extreme weather likely to occur more often in future, how can we adapt? It is human nature to look for big engineering solutions, and many are calling for more dredging, so that rivers can discharge faster, as well as for higher flood walls and sea defences. These options certainly have a part to play, but there could be far greater benefits from a more subtle ‘soft engineering’ approach – working with nature rather than against it.

A thoughtful article by George Monbiot tells the fascinating story of a small group of Welsh hill farmers who rebelled against the standard practice of chopping down trees, grubbing up hedges and digging drainage ditches – advocated in order to cram more sheep onto the land. In the words of the article, “It made no economic sense, the animals had nowhere to shelter, and the farmers were breaking their backs to wreck their own land.”

Instead, the Pontbren farmers planted shelter belts and woodlands using 120,000 native trees, and restored 16 miles of hedges. They created 12 new ponds, and protected natural wetlands instead of draining them. Although their main aim was to return to traditional farming methods and protect wildlife, the changes had another important effect. Heavy rain running down the hills simply disappeared when it reached the belts of trees. Research has now shown that the land planted with trees soaks up 67 times more water than traditional grazed pasture, and the amount of water running off the land is reduced by 78%. In fact, even though only 5% of the land was planted with trees, this was capable of reducing peak flows downstream by 29%.

In contrast, much of the engineering work traditionally carried out on UK rivers can actually make flooding worse. Dredging and straightening rivers, and building high banks that separate them from their flood plains, allows water to shoot straight down from the hills into the nearest town. A more intelligent approach is to allow rivers to form natural features such as meanders, braids and ox-bow lakes, which slow down the passage of the water and allow more of it to soak into the surrounding land, as well as trapping logs and boulders which can damage bridges and houses.

Dredging and building hard defences may be a necessary part of the solution in some cases, but it also causes further adverse impacts – damaging the ecosystem of the river and its floodplain, and using fuel and cement that result in further pollution and greenhouse gas emissions.

Softer approaches, in contrast, have multiple co-benefits. Planting trees stores carbon, thus helping to mitigate climate change and alleviate the risk of future extreme weather events. Trees stabilise the soil, thus reducing the amount of sediment swept into rivers, protecting the soil and improving water quality. By adding nutrients as leaves fall and rot, trees improve soil fertility. And they provide shade and shelter for livestock, and habitats for wildlife. Perhaps most remarkably, one study in Latin America showed that trees even make cows happier – it seems that they feel more secure with shrubs and trees to hide behind.

As well as protecting against flooding, trees can help to reduce the risk of droughts. By slowing down the passage of water to the sea and increasing absorption into the soil, trees allow water to be stored in the soil and vegetation, and more water is diverted to replenish underground aquifers.

In a future of more storms, floods and droughts as well as threats to biodiversity and food security, it makes sense to invest in solutions that tackle all these problems at once, rather than the false promise of dredging that can make matters worse in the long term.

 

 

 

 

Forests win at Warsaw: landmark deal on REDD+

Another climate conference; a few more tiny, acrimonious steps taken towards a global deal to cut carbon. As always, the 19th conference of the parties at Warsaw seemed like too little, too late.

But in one area there was an uncharacteristic outbreak of progress. Seven crucial decisions were approved, finalising a global framework for paying developing countries to protect their forests – otherwise known as REDD+. On top of this, the UK, Norway, the US and Germany put $280 million into the World Bank Bio-carbon fund for REDD+.

That’s not to say that everyone is happy with the outcome. The talks were marred by a dramatic walk-out of many delegates in protest at an attempt by Papua New Guinea, on behalf of the Coalition of Rainforest Nations, to re-insert an amendment that had previously been deleted.

The trouble with REDD+ is that it’s a great idea in theory, but highly controversial in practice. It offers the tantalising prospect of protecting rapidly disappearing tropical rainforests, rich in stored carbon, and achieving a vast range of co-benefits. As well as being hotspots of biodiversity, tropical forests prevent soil erosion, provide clean water, regulate regional rainfall patterns and provide homes and livelihoods for indigenous people.

But there are numerous problems in actually achieving these co-benefits in practice. For one thing, the indigenous people who should benefit most from REDD+ have often been marginalised, seeing the rights to their homeland traded away without the necessary “free, prior and informed consent.”

A further set of problems lurk in the innocent-sounding “+” at the end of the REDD+ acronym, which stands for – wait for it – “reducing emissions from deforestation and forest degradation, plus measures to conserve and enhance forest carbon stocks and promote sustainable forest management“. The bit after the “plus” refers to planting new forests, re-foresting previously cleared forests, or changing the way in which extraction of forest resources is managed. There is concern that the scheme could be used to subsidise commercial plantations, even perhaps indirectly encouraging the felling of native forests with a view to establishing subsidised oil-palm plantations on the land later.

The next barrier is the difficulty of monitoring and verifying the carbon emission reductions achieved. How do we know that a forest would have been felled if the payments were not made? And if we direct funding towards the countries where forests are most at risk of felling, are we not penalising the countries that have already taken the decision to protect their forests? What happens if the carbon stored in a REDD+ forest is lost or damaged due to fire, disease, illegal logging or climate change? How do we estimate the amount of carbon stored anyway?

Great progress has been made on all of these issues over the last decade. Satellite technology has improved monitoring and verification, and a comprehensive set of safeguards has been devised to ensure that indigenous people retain their rights and livelihoods, and that biodiversity is conserved. The rules set at Warsaw  specify that countries cannot receive money under REDD+ until they report on how social and environmental safeguards are being implemented.

The battle to strengthen REDD+ safeguards is certainly not over yet. At next year’s climate conference in Lima, delegates will decide exactly what information goes into the reports on safeguards. And despite all the progress over the last few years, one expert believes that the only truly successful REDD+ deal to date is the Surui project in Brazil, where the local indigenous tribe are leading the project.

But perhaps the greatest concern is that REDD+ will distract attention from the need to reduce carbon emissions from fossil fuels. The main source of finance is currently voluntary carbon offsets bought by companies, and opponents argue that this gives companies an excuse to carry on polluting. Even if REDD+ was incorporated into an international carbon cutting agreement, such as a cap-and-trade mechanism, some observers fear that the availability of relatively cheap forest carbon credits could drive down the price of carbon, removing the incentive to invest in low-carbon energy and energy efficiency measures. Or that without a global agreement on forest protection, deforestation could simply shift elsewhere.

This emphasises that we need a very carefully designed regulatory framework, to make REDD+ work without diminishing fossil fuel reduction policies. If we can achieve this, we can gain a vast range of co-benefits – cutting pollution, safeguarding biodiversity and protecting local livelihoods.