TY - JOUR
T1 - The water productivity score (WPS) at global and regional level
T2 - Methodology and first results from remote sensing measurements of wheat, rice and maize
AU - Bastiaanssen, Wim G M
AU - Steduto, Pasquale
PY - 2017/1/1
Y1 - 2017/1/1
N2 - Scarce water resources are one of the major constraints to achieve more food production. Food production needs therefore also to be evaluated in terms of water consumption, besides the conventional unit of land. Crop Water Productivity (CWP) is defined as the crop yield per unit of water evaporated. Contrary to crop yield, local benchmark values for CWP do not exist. This paper shows how operational earth observation satellites can measure CWP indirectly on a pixel-by-pixel basis, which provides an opportunity to define local, regional and global benchmark values. In analogy to a grading system for earthquakes (Richter) or wind force (Beaufort), a grading system for CWP is introduced: the Water Productivity Score (WPS). A regional scale WPS and a global version - Global Water Productivity Score (GWPS) - are presented. Crop yield zones are used to reflect local production potential, which reflects also the presence of irrigation systems besides general physio-graphical conditions. The 99th percentiles of climatic normalized CWP values at global scale are 2.45, 2.3 and 4.9 kg m− 3 for wheat, rice and maize respectively. There is significant scope to produce the same - or more - food from less water resources, provided that locally specific best on-farm practices are implemented. At the upstream level, Governments can use (G)WPS to define national water and food policies and use it as a means to report to the Sustainable Development Goal standards. At the downstream level, WPS helps to improve on-farm water management practices by growers, both for rainfed and irrigated crops. While the current paper is based on wheat, rice and maize, the same framework can be expanded to potatoes, sugarbeet, sugarcane, fruit trees, cotton and other crops.
AB - Scarce water resources are one of the major constraints to achieve more food production. Food production needs therefore also to be evaluated in terms of water consumption, besides the conventional unit of land. Crop Water Productivity (CWP) is defined as the crop yield per unit of water evaporated. Contrary to crop yield, local benchmark values for CWP do not exist. This paper shows how operational earth observation satellites can measure CWP indirectly on a pixel-by-pixel basis, which provides an opportunity to define local, regional and global benchmark values. In analogy to a grading system for earthquakes (Richter) or wind force (Beaufort), a grading system for CWP is introduced: the Water Productivity Score (WPS). A regional scale WPS and a global version - Global Water Productivity Score (GWPS) - are presented. Crop yield zones are used to reflect local production potential, which reflects also the presence of irrigation systems besides general physio-graphical conditions. The 99th percentiles of climatic normalized CWP values at global scale are 2.45, 2.3 and 4.9 kg m− 3 for wheat, rice and maize respectively. There is significant scope to produce the same - or more - food from less water resources, provided that locally specific best on-farm practices are implemented. At the upstream level, Governments can use (G)WPS to define national water and food policies and use it as a means to report to the Sustainable Development Goal standards. At the downstream level, WPS helps to improve on-farm water management practices by growers, both for rainfed and irrigated crops. While the current paper is based on wheat, rice and maize, the same framework can be expanded to potatoes, sugarbeet, sugarcane, fruit trees, cotton and other crops.
KW - Crop water productivity
KW - Crop yield
KW - Evapotranspiration
KW - Remote sensing
KW - WPS
UR - http://www.scopus.com/inward/record.url?scp=85001094071&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2016.09.032
DO - 10.1016/j.scitotenv.2016.09.032
M3 - Article
AN - SCOPUS:85001094071
SN - 0048-9697
VL - 575
SP - 595
EP - 611
JO - Science of the Total Environment
JF - Science of the Total Environment
ER -