Presentation is loading. Please wait.

Presentation is loading. Please wait.

Changes in Agricultural Yields without CO2 fertilization, Cline 2007.

Similar presentations


Presentation on theme: "Changes in Agricultural Yields without CO2 fertilization, Cline 2007."— Presentation transcript:

1 Changes in Agricultural Yields without CO2 fertilization, Cline 2007

2 Changes in Agricultural Yields with CO2 fertilization, Cline 2007 improved water use efficiency under higher CO 2

3 water intensity per kg of yield

4 changing diets FAOSTAT

5 Liu et al 2008 changing diets per-capita water demand in China 250 -> 860 m 3 between 1960 and 2000 Chinas population doubled during that period

6 Lannerstad 2009 changing diets

7 land use change FAOSTAT

8 land use change & land productivity change Haberl et al 2007 NPP – Net Primary Productivity

9 Conway & Waage 2010 increasing bioenergy demand ethanol and biodiesel production

10 Sagar et al, 2007 bioenergy & land demand

11 Sagar et al, 2007 m 3 water required per GJ from: sugar cane: 2516 maize: 2570 wheat: 4946 sorghum: 9812 rapeseed: jatropha: global average Gerben-Leenes, Hoekstra et al 2009 bioenergy & water demand 1liter of biofuel requires about the same amount of water as feeding one person for one day ethanol biodiesel

12 Jatropha cultivation - Fairless, 2007 every land use decisions is a water use decisions (Comprehensive Assessment 2007) bioenergy & water demand

13 Green and blue water in Agriculture Siebert et al 2009 % fraction of blue water in total agricultural water use

14 increased water productivity - adaptation to drier climate (and reduced pressure on other ecosystems) enhanced carbon sequestration in soils – mitigation of climate change reduced CO 2 emissions (zero tillage saves 80kg/ha/yr compared to conventional tillage from reduced tractor fuel needs) increased (agro-bio) diversity – more resilient systems reduced erosion, nutrient and pesticide loads FAO 2007 soil carbon sequestration potential Multi-functional systems – integrating climate mitigation and adaptation e.g. conservation agriculture

15 in multi-functional systems Multi-functional systems e.g. agroforestry - rotational woodlands, Tanzania intercroping of food crops with leguminous trees (Acacia) Verchot 2007 felling trees after 10 years

16 Critical hotspots: rainfed drylands Rockström et al 2009

17 Critical hotspots: rainfed drylands low yield / water productivity all crops Wisser et al 2009

18 dry spells and droughts projected to increase with climate change Critical hotspots - hunger

19 fertilizer gap in Africa FAO annual average N-P-K application

20 Burkina Faso ZimbabweEthiopia Grey, 2004/2005 climate variability, agriculture, GDP link

21 Foreign Direct Investment (land grabbing) GTZ 2009 e.g. by Chinese companies: IKO: 10,000 ha rice in Cameroon SUCOCOMA: 10,000 ha sugarcane in Madagaskar Viscount Energy: sugarcane in Nigeria Int. Water & Electric Corp: 100,000 ha corn in Tanzania Heibei Company: 40,000 ha poultry etc in Uganda Int. Water & Electric Corp 100,000 ha corn in Zimbabwe also water grabbing Other pressures

22 Increasing water productivity – more crop per drop Comprehensive Assessment Today Managing water along the green – blue continuum

23 financial incentives – payments for environmental services Enabling conditions / incentives -> water implications of CDM -> integration of adaptation & mitigation

24 Syria 4 Morocco 22 Lebanon 28 Algeria 79 Tunisia 97 Jordan 196 Libya 557 net VW imports as % of renewable water resources Yang et al 2007 however, there are concerns about national food security and local livelihoods when relying on virtual water imports and there is an employment problem if local agriculture is phased out imports of virtual water in the MENA region

25 Regreening Sahel - a success story Geo

26 Regreening Sahel - a success story Burkina and Niger Reij et al 2009 Zai pits

27 Regreening Sahel - a success story Burkina and Niger Reij et al 2009 Contour stone bunds

28 Regreening Sahel - a success story Burkina and Niger Reij et al 2009 Farmers-managed natural regeneration (FMNR) of trees


Download ppt "Changes in Agricultural Yields without CO2 fertilization, Cline 2007."

Similar presentations


Ads by Google