Through The Sandglass

The beauty of volcanic detritus

Sometimes, the fewer words the better. The words of Russian photographer Andre Ermolaev, "...an inexpressible combination of colors, lines, and patterns," are sufficient to introduce his stunning images of Icelandic Rivers. The collection is highlighted on The Superslice site and elsewhere, including here and Ermolaev's own site (in Russian).

Sand Wars

Apologies for being off-line for a while, but circumstances beyond my control have meant that posting has been a low priority.

However, please go to this link for news of what will be a powerful documentary by the award-winning director, Denis Delestrac: Sand Wars

More on this later, no doubt....

Sunday Sand: The Palace of Great Happiness, and a GLOF

I was delighted (but envious) when my friend Patricia brought me back a sample of sand from her recent visit to Bhutan. The sand came from one of the country’s most sacred places (and its old capital), Punakha, at the confluence of two great rivers, the Mo Chu (the mother river) and the Pho Chu (the father). The Palace, the Punakha Dzong, is also known as Pungtang Dechen Photrang Dzong, the palace of great happiness, and this magnificent structure originally dates from the 17th century. But happiness has not reigned continuously during its long history. It has been re-built many times over the centuries after fires and earthquakes, and it is regularly threatened by floods, the most recent severe event occurring in 1994.

And there’s a good reason for the floods, created not by the mother river, but by the father. Follow the Pho Chu upstream from Punakha, and you climb rapidly into the high Himalayas, towards the snow caps, the ice fields, and the glaciers that provide the source of the river. Now glaciers are environmentally careless, dumping and reworking the great loads of rock and sediment that they carry with no regard for landscape maintenance. The great piles of glacial litter that remain (moraines) can often act as dams for the glacial melt water, and lakes build up behind them. In the lower images, below, there are four glaciers feeding the upper reaches of the valley down which the Pho Chu flows:

 

Partly frozen in the image on the left, open and melted on the right, are a series of such glacial lakes. Most of the time, such lakes are benign, simply adding an extra element to the grandeur of glaciated mountains anywhere in the world. However, as the Nova article on glacier hazards notes, “Once such a lake has formed, melting and retreat of the glacier front accelerates because water transports heat much more efficiently to the ice front than air can.” And, ultimately, that’s when a benign landform can turn nasty. The natural dams reach the point that they can no longer hold back the waters accumulating behind them, and burst, letting loose a massive torrent of floodwaters charging down the valley. Such was the case on October 7th, 1994, with the lake, Lugge Tso, seen clearly in the satellite images. Also clearly visible is the breach in the moraine dam and the flood channel downstream of it. Such an event is known in the trade as a glacial lake outburst flood, or “GLOF.”

At Punakha, the typical average river flow is perhaps a couple of hundred cubic meters – around a thousand bath tubs – per second. In October 2004, the peak river flow measured downstream from Punakha, and more than a hundred kilometres from the lake, was 2500 cubic meters per second. And this is what Punakha looked like (with a normal view for comparison):

The father river has adopted a second channel, and unimaginable tons of sand are being re-distributed along the valley – a re-sculpturing of the landscape that will change everything for the flow of the river in both normal times and flood. But there are man-made changes in the works, too – given that there are another 2500 glacial lakes besides Lugge Tso in the Bhutan Himalayas, a grand scheme is underway. The defences put in place after the 1994 flood are regarded as inadequate, and the current project is to move the confluence of the mother and father rivers 300 meters downstream of its present location:

As described in an article on kuenselonline.com a couple of years ago:

The department of geology and mines (DGM) has a proposal to divert the Phochu and Mochu rivers to protect Punakha dzong in case of a glacial lake overflow flood (GLOF) and cyclone floods.

It proposes moving the confluence of the two rivers more than 300 m downstream.
“We’ve sent to the dzongkhag an estimate of Nu 508,310 to survey and study the river basin area,” said Ugyen Wangda, chief geologist of DGM. If approved, construction would take around three years.

The present defenses of the Punakha dzong, built after the 1994 floods, can withstand only 18 million cubic metres (cu m), according to DGM. “The proposed diversion will protect the dzong from even a 53 million cu m flood, if the Lunana lakes of Rapstreng and Thorthormi burst,” said Ugyen Wangdi.

The proposal came up in a May 2009 home ministry meeting after the GLOF false alarm in Punakha, when an underground lake in Tshojo glacier had burst. “The main concern was on how to evacuate the holy relics of the Ranjung Kharsapani and the Machen to a safer place,” said Ugyen.

The main danger is from the headwater of Phochu, where there is a chance of GLOF, if the Rapstreng and Thorthormi lakes overflow into each other, according to DGM.

“We plan to divert the Phochu two or three kilometres before the dzong and take it over the paddy fields, which are currently on the left banks,” said Ugyen.

A kilometre long and three metres broad giant wall could be built further away from the dzong’s current wall. The enlarged area, behind the wall, is proposed to be converted into a large park. “If there is GLOF and the river overflows its banks, there should be no impact as the river basin will be very large,” said Ugyen Wangdi.

The classic and spectacular view of the Palace of Great Happiness will be consigned to history.

But back to the sand. These are raw, young grains, only recently ripped out of their Himalayan parent-rocks, tumbled downstream by everyday river flow and the occasional GLOF, witnesses to violence, but barely changed from their original crystal forms. Another lovely sand - thanks, Patricia.

 

 

[This is the second time I have been fortunate to have a Bhutan sample for the Sunday Sand series – see the other one here.]

{A very good summary of GLOFs of the Bhutan Himalayas: Chhopel, Karma (2006-03-15). "Flash Floods and Debris Flows due to Glacial Lake Outburst Floods" (ppt). Proceedings of the International Workshop on Flash Flood Forecasting coordinated by the U.S. National Oceanic and Atmospheric Administration's National Weather Service and the World Meteorological Organization, San José, Costa Rica, March 2006.

Header image licensed under the Creative Commons Attribution-Share Alike 2.0 Generic license, http://flickr.com/photos/59731892@N00. Second photo of Punakha Dzong: http://www.globeimages.net/data/media/8/Punakha_Bhutan.jpg ]

What is happening to British dunes? The testimony of Eryngium maritimum

It was tempting to make the subject of this entire post the egregious activities of the outstanding American buffoon, Donald Trump (plea to trans-Atlantic readers: if you can’t do anything else about him, could you please keep him away from our shores?). As documented in the recent film, You’ve Been Trumped (which I haven’t yet seen, but perhaps look forward to), an entire stretch of the natural Scottish coastal dune system has been destroyed by Trump’s typically megalomaniacal golf course development (aided and abetted, it has to be said, by the Scottish Government). It is, of course, ironic, that it was the topography of dune ridges that first brought the game to Scotland – as I described in Sand:

The Old English word for ridges is hlincas, from which the term links is derived, and it was in this terrain that small leather balls stuffed with goose feathers were first whacked about and the revered game of golf—or gouff, or goffe—originated. Many of the world’s finest golf courses, including the Old Course at the Royal and Ancient Golf Club at St. Andrews on the east coast of Scotland, owe their location to coastal dune systems.

A second irony (a word that hardly seems adequate) is that “The Donald” has the gall to Trumpet his scheme as environmentally beneficial. This, from an NYT interview with Anthony Baxter, the film’s director:

Q. Mr. Trump is on the record as saying that his development would be “environmentally perfect ” and that the area would in fact be better off environmentally after the golf course was built. Were there any major environmental groups that supported the project?

A. There was not one credible environmental group that supported this development. Friends of the Earth Scotland, Scottish Natural Heritage, the Scottish Wildlife Trust, the Royal Society for the Protection of Birds, the Ramblers Association of Scotland — all of these groups were dead set against this development.

The Royal Society for the Protection of Birds actually issued a press release when Mr. Trump was given the go-ahead saying that Scotland’s green policy had been sold down the river by this decision. Not a single expert was standing up and saying that it made sense to tamper with this very unique sand dunes system.

But the management of Britain’s coastal dunes raises questions far beyond the tragic activities of one aggressive clown.

 

Coastal dune systems are, by nature, dynamic. On the front line of the power struggle between land and sea, pounded by winds and storms, they are almost always on the move. However, unlike their desert counterparts, the intervening quiet periods allow specialised – and hardy – vegetation to take root; there’s a remarkably diverse ecosystem of plants that enjoy a substrate of shifting sand. If the vegetative cover comes to dominate, then the dunes become stabilised, resistant to the day-to-day attacks of wind and waves, if not to powerful storms. And, because the mobility of coastal dune systems is inconvenient to the human inhabitants of those environments, who wish to bask in vistas that are static and benign, conscious attempts to stabilise with vegetation (if not completely remove) coastal dunes are common. This activity, combined with the reduction in free-range grazing of animal herds, and a fluctuating climate, have caused a wholesale change in the UK’s natural coastal dune systems.

I’m not someone who routinely consults the horticultural experts in the media, but I was struck by a piece in Friday’s Guardian newspaper that began:

What has happened to Britain's sand dunes? My childhood recollections are of wild and windy places; of a fine spindrift of sandy particles streaming from the dune ridges; of marram grass etching precise circles in dry sand with the tips of their leaves; of wavering films of sand flowing across rippled sands. Fast forward 50 years, and … the golden sand has been replaced by a thick thatch of matted grass, burgeoning stands of bracken and scrub, and increasing groves of willow and birch. And as bare sand has become something of a rarity, so many beautiful sand dune species have declined to near-oblivion today. Many of our rarer plants and animals have spent millennia evolving to cope with shifting sands. Like carrot seedlings in an allotment, they need bare ground into which to seed, and simply can't compete with choking blankets of coarse vegetation.

Written by Andy Byfield, one of the founders of the wild plant charity Plantlife, the piece argues that “Drastic action is needed to save the native plants that thrive on our sand dunes.”

It’s understandable to assume that flowering plants that thrive in sand must reflect desiccation and struggle in their appearance. But the opposite is often the case – for example, from my recent Australian desert trip:

And this is as true of the British coast as it is of Australia’s red centre. The image at the head of this post is of the spectacular Sea Holly, Eryngium maritimum, that Byfield justifiably dubs the “king of the dunes”:

an architectural beauty of the sandy beaches and sand dunes around our shores. The plant's central cone of flowers is reminiscent of members of the daisy family, such as echinacea or rudbeckia, but sea holly is a relative of the carrot. The ruff of petals is actually a ring of spiny bracts that encircle and protect the flowers like the plates of a Stegosaurus or the frills of a Triceratops. The whole plant is a metallic blue-green, seemingly verdigrised like a bronze garden statue in miniature.

He goes on to describe the sea holly as typical of the plants that need open, moving sand and are being extinguished by the overly (and coarsely) vegetated character of their favourite environment today:

Sea holly is supremely adapted to growing in mobile sand. Its deep-seated rootstock penetrates the substrate to a depth of 1m or more, and the plant takes a masochistic delight in being buried by an avalanche of sand…

Fortunately, as a species of the exposed foredunes (those next to the beach), sea holly is not faring as badly as some: indeed many other dune plants are faring badly. Take the fen orchid, an elusive green orchid of the South Welsh dunes: known to be locally abundant just a few decades ago, the species has declined from hundreds of thousands of plants at 10 sites to just a few hundred plants at one location today.

A typical stretch of South Welsh dunes is along the coast at Kenfig, the namesake settlement of which also figured in Sand:

Kenfig was established in the twelfth century as a small port and farming community on a river sheltered by the coastal dunes. It survived the attacks of marauding Welsh tribes, but not the forces of nature, provoked by grazing and the ensuing destabilization of the sand. These factors, probably combined with climate change as the cold period often referred to as “the Little Ice Age” approached, meant that the dunes were on the move. By the fourteenth century, large parts of the town and its fields were covered, and by the middle of the seventeenth century, it was completely abandoned.

But these days the dunes are no longer on the move and have become, possibly also as a result of the nutritious nature of polluted rain, vegetated and stable – hence the struggles of the fen orchid and the sea holly. And so a radical experiment has just been launched – the dunes are being bulldozed, not in the interests of a megalomaniac, but in order to restore the original biodiversity. The project is led by Byfield, who is Plantlife’s Landscape Conservation Manager, and involves removing all vegetation from ten acres of sand. The following is from the project website:

• Only 2% of the dune system at Kenfig now comprises bare sand, down from around 40% in the mid 1940s. Early plant colonists including sea rocket, sea holly and yellow horned-poppy need bare sand to colonise – and these suffer if a dune system becomes too stable.

• Regular ground disturbance and open patches of sand will reduce the dominance of vigorous plant species and allow rarer, less vigorous species to return. As well as fen orchid, other declining species which will benefit include round leaved-wintergreen, marsh helleborine and early marsh orchid.
• Plantlife will be introducing trial management work aimed at encouraging fen orchid and allowing better conditions for many other species including the rare dune bryums and petalwort to develop.

This will be a fascinating experiment in reversing natural and human-induced environmental change.

And, while I am discussing Eryngium maritimum, I must report some interesting commentary that I came across with respect to its truly extraordinary and diverse medicinal applications. It (particularly its root) is variously described as curing and stimulating flatulence, as an aphrodisiac, a diuretic, a potent inflammation modulator, and an inducer of extreme perspiration. The name of the genus Eryngium is supposedly derived from the Greek for eructation, and, furthermore, Plutarch is reported as telling the story that

'They report of the Sea Holly, if one goat taketh it into her mouth, it causeth her first to stand still and afterwards the whole flock, until such time as the shepherd takes it from her.'

Perhaps someone could brew up some sea holly roots for The Donald?

 

[Photos of Sea Holly: Karen Davies and the National Education Network, Clive Hurford and the Guardian.]