Responses of food production systems to climate change:sensitivity and vulnerability

摘要

Climate warming has prolonged the optimization of crop-growing seasons,shortened actual growth periods,and changed crop-planting boundaries.It also has boosted crop yields in certain regions while compromising crop quality and affected the occurrence of meteorological disasters and pest diseases damage,which has resulted in reduction in grain yield.Crop production systems will evidence more sensitivity to climate change in future;for example,with an increase of 1°C in temperature,the average growth period will be shortened by 17 days for winter wheat and 7-8 days for maize and rice.Of course regional differences will exist.Climate change will threaten crop yield stability and affect crop quality.Vulnerability will be addressed in regard to extreme climatic events,which include reducing exposure and improving adaptive capacity,because the exposure of rain-fed agriculture is greater than that of irrigated agriculture.Therefore,we propose three suggestions to reduce the vulnerability of crop production systems to climate change.First,strengthen the evaluation capacity construction of sensitivity,which includes(1)refining and improving all types of evaluation indicator systems and models;(2)innovating and developing evaluation methods and tools;and(3)combining field observation and case studies,so that(1)the impact of climate change and sensitivity can be assessed scientifically;(2)uncertainty in the study can be identified and reduced;and(3)improved understanding of climate systems and their changes,climate change impact,and sensitivity will be achieved.Second,strengthen adaptive capacity construction for crop production systems,which includes(1)rebuilding existing farmland infrastructure to improve meteorological disaster defences;(2)adjusting agriculture structure and adopting new crop varieties with enhanced resistance;(3)popularizing water-saving technology and dry farming technology;and(4)further researching interdisciplinary theories and methods.Third,strengthen function construction for natural and social systems,which includes(1)popularizing innovative technology;(2)progressing agricultural insurance;and(3)improving energy efficiency and increasing carbon sequestration and emission reduction ability to maintain a favorable ecological environment.