Quantification of ozone exposure- and stomatal uptake-yield response relationships for soybean in Northeast China
Quantification of ozone exposure- and stomatal uptake-yield response relationships for soybean in Northeast China
复制标题
中国东北地区大豆臭氧暴露-气孔吸收-产量响应关系的量化
DOI：
10.1016/j.scitotenv.2017.04.231
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发表时间：
2017
影响因子：
9.8
通讯作者：
Hu Enzhu
中科院分区：
文献类型：
--
作者：
Zhang Weiwei;Feng Zhaozhong;Wang Xiaoke;Liu Xiaobing;Hu Enzhu
随着环境O3浓度的不断升高，高地面O3对东北地区农业生产构成了新的威胁。关于它对这一关键农业区大豆生产的影响，人们知之甚少。以东北地区4个典型大豆品种为材料，通过连续2个生长季的累积O3通量-响应和气孔O3通量-响应关系，研究了O3胁迫对大豆产量的影响。结果表明，AOT 40、SUM 06和W126分别是相对种子产量下降5%的临界值，分别为4.2、7.6和6.8 μmol·mol-1·h。O3对植物的影响受冠层叶位的影响。改进的Jarvis气孔导度模型包括叶（节）位，与田间实测结果吻合较好。当植物毒性臭氧剂量超过9.6 nmol·m− 2·s− 1（POD9.6）时，气孔O3通量与大豆相对产量之间的线性关系最好，与大豆相对产量下降5%相关的POD9.6和常用的POD 6分别为0.9 mmol·m− 2和1.8 mmol·m− 2。O3浓度高于38 nmol·mol− 1时，POD为9.6，导致大豆种子产量损失。目前，大豆在环境O3下的年产量损失估计在23.4%和30.2%之间。研究得到的O3剂量-响应关系及阈值对东北地区大豆生产的区域O3风险评价具有一定的参考价值。
High ground-level O3is a new threat to agricultural production in Northeast China with the increasing ambient O3concentration. Little is known about its impacts on soybean production in this key agricultural region. Accumulated O3exposure-response and stomatal O3flux-response relationships were developed during two continuous growing seasons to evaluate O3-induced yield reduction of four typical soybean cultivars in Northeast China. Results showed that critical levels ofAOT40 (accumulated hourly O3concentrations over a threshold of 40 nmol·mol− 1),SUM06 (sum of all hourly average O3concentrations over 0.06 μmol·mol− 1) andW126 (sum of O3concentrations weighted by a sigmoidal function) in relation to 5% reduction in relative seed yield were 4.2, 7.6 and 6.8 μmol·mol− 1·h, respectively. The effect of O3on plants was influenced by leaf position in canopy. An improved Jarvis stomatal conductance model including leaf (node) position fitted well with field measurements. The best linear relationship between stomatal O3flux and relative soybean yield was obtained when phytotoxic ozone dose was integrated over a threshold of 9.6 nmol·m− 2·s− 1(POD9.6) to represent the detoxification capacity of soybean.POD9.6and the commonly usedPOD6in relation to 5% reduction in relative seed yield of soybean were 0.9 mmol·m− 2and 1.8 mmol·m− 2, respectively. O3concentrations above ~ 38 nmol·mol− 1contributed toPOD9.6and caused seed yield loss in soybean. Current annual yield loss of soybean at ambient O3was estimated to range between 23.4% and 30.2%. The O3dose-response relationships and corresponding thresholds obtained here will benefit regional O3risk assessment on soybean production in Northeast China.