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© Pascal Peduzzi, 2015 Sand : Rarer than one thinks Sand : rarer than one thinks Dr Pascal Peduzzi Director of Science United Na@ons Environment Programme Geneva November 2015
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Sand : rarer than one thinks
Dr Pascal Peduzzi Director of Science
United Na@ons Environment Programme Geneva November 2015
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Glaciers & rivers move 24 billions tonnes per year
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Humans are extracting and moving btw 47 and 59 billions tonnes per year (2009)
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
0
500'000
1'000'000
1'500'000
2'000'000
2'500'000
3'000'000
3'500'000
4'000'000
1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014
World
China
All other countries
1000 Ton
s of cem
ent / year
60 %
China uses more in 4 years than USA in one century Cement :
4’180’000’000 x 7 = …
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
30 billions t. of sand & gravels (2014)
• Equivalent to a wall of 20 m x 20 m around the equator !
20 m
20 m
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
What are we doing with sand ?
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Roads
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Buildings
828 m
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Dams
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Glass
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Electronics and other industrial uses
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Land reclamation
2001 2011
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Land reclamation
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Beach nourishment
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Where is it from ?
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Where is it from ?
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Quarries
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
What are the impacts ?
• Impacts on landscape • Lowering the ground • Lost of soil
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
River beds
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
• Pollu@on and changes in levels of pH • Lateral instability • Can change the riverbed itself • Incision can drain to a lower level resul@ng in reduced aquifer storage
• May increase flood frequency and intensity by reducing flood regula@on
• Can lower the water table, thus exacerba@ng drought occurrence.
Impacts from river extrac@on.
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Lake shores
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Lake Poyang, the largest source of sand in China: 236 million m3 / year
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Coastal and beach
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
• Erosion occurs either directly or indirectly • Reduce protec@on from storm surge • Destroy habitat from beach fauna (e.g. turtles, crabs,…)
• Reduce protec@on from sea level rise
Impacts from coastal extrac@on.
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Marin sand dredging
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Impacts from Marin extrac@on
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Impacts from Marin extrac@on
• On seabed flora and fauna • Destroys organisms, habitats and ecosystems • Affects the composi@on of biodiversity • Usually leading to a net decline in faunal biomass and abundance
• Or a shih in species composi@on • Too fine par@cles are rejected by dredging boats… changing water turbidity.
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Once trapped into concrete, the sand is lost.
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Impacts(on! Description!
Biodiversity! Impacts(on(related(ecosystems(services((e.g.(fisheries)(
Land(losses! Both(inland(and(coastal(through(erosion(processes(
Hydrological(function! Change(in(water(flows,(flood(regulation,(or(on(marine(currents(
Water(supply! Through(both(lowering(of(the(water(table(and(pollution(
Infrastructures(! Damage(to(bridges,(river(embankments(and(coastal(infrastructures(
Climate! Directly(through(transport(emissions,(indirectly(through(cement(production(
Landscape! Coastal((e.g.(beach)(erosion,(quarries,(pollution(of(rivers(
Extreme(events! Decline(of(protection(against(extreme(events((flood,(drought,(storm(surge)(
!
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
SOLUTIONS ? We need : • Monitoring • New legisla@ons • Op@mize the use of exis@ng buildings and infrastructures
• Incen@ves (taxes and subven@ons)
• Recycling concrete and glass • Use ashes from wastes • Building with alterna@ve material
• Sound environmental impacts assessment prior mining, quarrying and land reclama@ons be authorized.
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Linear economy
Mines Industry Consumers Waste / Dump
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Circular economy
Industry Consumers
Waste as resource
© Pascal Peduzzi, 2015 -‐ Sand : Rarer than one thinks
Sand : rarer than one thinks www.grid.unep.ch
