|CHEN, XIUZHI - China Agricultural University|
|VAN OEL, PIETER - Wageningen University|
|XU, ZHENCI - University Of Michigan|
|ZHOU, BO - China Agricultural University|
|LI, YUNKAI - China Agricultural University|
Submitted to: Journal of Cleaner Production
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/12/2019
Publication Date: 10/18/2019
Citation: Chen, X., Thorp, K.R., van Oel, P., Xu, Z., Zhou, B., Li, Y. 2019. Environmental impact assessment of water-saving irrigation systems across 60 irrigation construction projects in northern China. Journal of Cleaner Production. 245. https://doi.org/10.1016/j.jclepro.2019.118883.
Interpretive Summary: To address increasing water shortages and demands for water in northern China, modern irrigation systems are being advanced through large irrigation construction projects. This study aimed to quantify the water and carbon footprints attributed to construction and maintenance of modern irrigation systems. The water footprint for irrigation project construction was up to 10% of water saved through use of modern, efficient irrigation systems. The carbon footprint for irrigation project construction was up to 50% of emissions from all agricultural activities. Long-term drip irrigation was shown to increase crop yield while reducing environmental impacts. Results of the study are useful for guiding sustainable development of irrigation infrastructure in northern China.
Technical Abstract: With the increasing water shortages and demands for water in northern China, agricultural production has become more reliant on modern, water-saving irrigation technologies, which have been advanced through irrigation construction projects. Obviously, efficient irrigation management can lead to water savings and increased crop yield, but the water consumption and greenhouse gas emissions resulting from the construction and operation of irrigation projects can impact the environment. The overall environmental impact of irrigation projects in northern China remains unknown. In the present study, basic information on irrigation construction methods, materials, and equipment was obtained from irrigation construction enterprises through questionnaire investigations and acceptance reports. Sixty typical irrigation projects were identified in north China, and the water (WF) and carbon footprint (CF) of each project was calculated and studied using lifecycle assessment methods. The WF of implementing water-saving irrigation projects accounted for an estimated 0.2-1.5% of total WF and 2.3-8.8% of the amount of water saved by increasing irrigation efficiency. Thus, the WF for the construction of water-saving irrigation equipment is substantial. If construction impacts are not accounted for, the amount of water saved after implementation is overestimated from 3% to 23%. The CF for irrigation project construction accounted for 31% to 53% of emissions from all agricultural activities. Because the CF of irrigation construction projects was found to be positively correlated with the level of financial investment, a simple methodology for estimating CF from project cost was proposed. The comprehensive WF and CF analysis of irrigation construction projects in northern China demonstrated that long-term drip irrigation could increase crop yield while reducing the environmental impact.