Effects of elevated O3 concentration on winter wheat and rice yields in the Yangtze River Delta, China

Abstract

a b s t r a c tThe effects of a continuing rise of ambient ozone on crop yield will seriously threaten food security in China. In the Yangtze River Delta, a rapidly developing and seriously air polluted region in China, innovative open-top chambers have been established to fumigate winter wheat and rice in situ with elevated O 3 . Five years of study have shown that the yields of wheat and rice decreased with increasing O 3 concentration. There were significant relationships between the relative yield and AOT40 (accumulated hourly O 3 concentration over 40 ppb) for both winter wheat and rice. Winter wheat was more sensitive to O 3 than rice. O 3 -induced yield declines were attributed primarily to 1000-grain weight and harvest index for winter wheat, and attributed primarily to grain number per panicle and harvest index for rice. Control of ambient O 3 pollution and breeding of O 3 tolerant crops are urgent to guarantee food security in China.

Ozone concentrations, flux and potential effect on yield during wheat growth in the Northwest-Shandong Plain of China

“…Mills et al (2007) summarized numerous AOT40-based response functions for some crops obtained by several OTC experiments in Europe and the USA. In China, AOT40-based models have recently been created for the Yangtze River Delta (Feng et al, 2003;Wang et al, 2012). Table 1 shows the yield loss estimations calculated by different ozone exposure-response functions.…”

“…Another source of uncertainty is that the yield response functions may also vary with different wheat cultivars, plant locations, and other environmental conditions when using the same index (Heck et al, 1982;Wang and Mauzerall, 2004;Zhu et al, 2011;Wang et al, 2012). In addition, functions were obtained from OTC experiments and the indices were obtained from natural ecosystems, which may also result in some uncertainties (Wang et al, 2012).…”

“…In addition, functions were obtained from OTC experiments and the indices were obtained from natural ecosystems, which may also result in some uncertainties (Wang et al, 2012). Fortunately, more FACE experiments were utilized to study the effects of O 3 on crop yield loss, which may improve the assessment accuracy (Zhu et al, 2011;Feng et al, 2012).…”

“…To quantify these losses, some O 3 exposure/flux-response models have been generated by using OTC or FACE experiments (Heck et al, 1982;Mills et al, 2007;Feng et al, 2012;Wang et al, 2012). Although flux-based indices have advantages over exposure-based indices owing to their linkage to stomatal uptake of plants, there are some practical limitations that hinder their use in current research.…”

Effects of elevated O3 exposure on nutrient elements and quality of winter wheat and rice grain in Yangtze River Delta, China

“…Since 2003, open-top chambers (OTCs) have been used to investigate the effects of elevated O 3 exposure on winter wheat and rice in physiological processes (Zheng, 2006;Zheng et al, 2007), yield (Wang et al, , 2012, soil microorganism (Chen et al, 2008(Chen et al, , 2010, agroecosystem (Zheng et al, 2011), in Yangtze River Delta, China. The objectives of this study is to investigate the changes of nutrient elements and quality of winter wheat and rice grain under the elevated O 3 exposure.…”