Factors affecting crop production water footprint: A review and meta-analysis

Climate change and human activities are considered to be the biggest threats and challenges to crop productivity and increase water stress in agricultural systems. Water footprint is a quantitative indicator that closely links crop production to the water cycle, which provides new insights for the assessment of water use in agriculture. The water footprint of crop production (CWF) is susceptible to a variety of factors. However, the current research on the temporal and spatial pattern and influencing factors of CWF mostly focus on the quantitative and correlation analysis of CWF, while the attribution analysis and factor importance analysis of regional discrepancies of CWF are rare. Here, we examined the comprehensive correlation coefficients between the influencing factors (average temperature, precipitation, sunshine hours, relative humidity, wind speed, fertilizer application, effective irrigation area, per capita GDP, crop yield, agricultural machinery power) and CWF using meta-analysis methods. Through the comprehensive correlation coefficient, the factors affecting the CWF in different regions and the key factors reducing the CWF were identified. Our findings provide new insights for the scientific management of water use in agriculture around the world.