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Integrated Land and Water Management Green and Blue Water. Holger Hoff Potsdam Institute for Climate Impact Research Stockholm Environment Institute. Integrated Land and Water Management Green and Blue Water. „managing rainfall as the key resource“. Falkenmark & Rockström 2005.
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Integrated Land and Water Management Green and Blue Water Holger Hoff Potsdam Institute for Climate Impact Research Stockholm Environment Institute
Integrated Land and Water Management Green and Blue Water „managing rainfall as the key resource“ Falkenmark & Rockström 2005 „more crop per drop“ „every land use decision is a water use decision“ Molden et al 2007
Partitioning of rainfall Evaporation -> increasing productivity, „creating more with less“ Blue Water: globally ~ 1/3 of rainfall
“IWRM” only addresses 1/3rd of the total water resource ~100.000 km3/yr
or even less in “drylands” e.g. Kenya SEI, 2005 5.7%
% Siebert et al 2009 Green & blue water in agriculture % irrigation of total water use irrigation (blue) water: ~ 1.300 km3 / yr green water cropland: ~ 5.000 km3 / yr green water grazing land: ~ 10.000 km3 / yr
Blue water availability Gerten et al 2011 m3 / capita / year
Green plus blue water availability Gerten et al 2011 m3 / capita / year
Crop water productivity (m3 per 1000kcal) Gerten et al 2011
“self sufficiency potential” as a result of green plus blue water availability in combination with current crop water productivity Gerten et al 2011
Integrated Land & Water Resources Management (ILWRM) across scales International “landscape configuration” e.g. national policies, investments AWM
Integrated Land & Water Resources Management (ILWRM) across basins
Integrated Land & Water Resources Management (ILWRM) across basins “INTERVENTIONS” “SUBSISTENCE”
Integrated Land & Water Resources Management (ILWRM) e.g. Jatropha / India Fairless, 2007
Integrated Land & Water Resources Management (ILWRM) e.g. pine plantations South Africa „streamflow reduction activities“ (National Water Act) water consequences of „million tree campaign“, CDM, etc?
Integrated Land & Water Resources Management (ILWRM) e.g. land degradation Kenya • upstream erosion -> downstream reservoir siltation -> reduced: • 1. storage capacity, • 2. irrigation water availability • 3. hydropower production -> Green Water Credits (Payments for Ecosystem Services)
e.g. land degradation, in-situ effect: -> reduced soil (green) water storage climate change: need for more water storage green water options blue water options Green water solutions tend to be: • small-scale • decentralized • low-tech • less energy-intensive
Competition for water & land - urbanization e.g. Amman urban sprawl onto most fertile rainfed land no spatial planning no connection between water and land at the institutional level Al Rawashdeh et al 2006
Competition for water & land – livestock vs crop need for integrated crop – livestock production systems e.g. synergies from using straw / other residues for feed
Competition for water & land – bioenergy (vs. food) 1 liter of biofuel requires about the same amount of wateras feeding one person for one day land requirement (in ha) for biofuels per car: Sagar et al, 2007 • nexus / opportunities e.g.: • agroforestry • using / rehabilitating marginal land with Jatropha
crop production crop production timber timber recreation recreation rangeland farmland spiritualvalues spiritualvalues Livestock livestock water provisioning water provisioning erosion control erosion control nutrientretention nutrientretention Provisioning services Regulating and supporting services Cultural services Competition for water & land – ecosystem services (essential in particular for poor livelihoods) “agro- ecosystems” water provisioning carbon sequestration carbon sequestration -> ecosystems as natural water infrastructure -> negotiating and managing tradeoffs in multi-use systems rather than single-objective optimizations (yield)
“Global drivers / management of water & land” via trade and foreign direct investment e.g. 1) increasing land scarcity in China -> rapidly growing feed imports from Brazil -> moving agricultural frontier into Amazonia -> deforestation -> less transpiration -> less moisture transport to the La Plata basin 2) increasing water scarcity in the MENA region, e.g. Egypt -> FDI e.g. in Ethiopia -> more irrigation upstream, less blue water flow in the Nile -> increasing downstream water scarcity
a success story Zai pits, e.g. Burkina Faso Reij et al 2009
a success story farmers-managed natural regeneration (FMNR) of trees, e.g. Niger Reij et al 2009
a success story regreening of the Sahel Geo 4 2007