排序方式: 共有4条查询结果,搜索用时 0 毫秒
1
1.
Zhang Yanhui Hu Tianlong Wang Hui Jin Haiyang Liu Qi Lin Zhibin Liu Benjuan Liu Hongtao Chen Zhe Lin Xinwu Wang Xiaojie Ma Jing Sun Delin Sun Xiaoli Tang Haoye Bei Qicheng Cherubini Francesco Arp Hans Peter H. Xie Zubin 《Plant and Soil》2021,459(1-2):329-342
Plant and Soil - Although phytolith analysis is a promising tool for reconstructing the palaeovegetation in grassland ecosystems, no phytolith study has yet attempted to quantitatively reconstruct... 相似文献
2.
Haoye Tang Masayuki Takigawa Gang Liu Jianguo Zhu Kazuhiko Kobayashi 《Global Change Biology》2013,19(9):2739-2752
Using a high‐resolution (40 × 40 km) chemical transport model coupled with the Regional Emission inventory in Asia (REAS), we simulated surface ozone concentrations ([O3]) and evaluated O3‐induced wheat production loss in China and India for the years 2000 and 2020 using dose–response functions based on AOT40 (accumulated [O3] above 40 ppb) and PODY (phytotoxic O3 dose, accumulated stomatal flux of O3 above a threshold of Y nmol m?2 s?1). Two O3 dose metrics (90 days AOT40 and POD6) were derived from European experiments, and the other two (75 days AOT40 and POD12) were adapted from Asian studies. Relative yield loss (RYL) of wheat in 2000 was estimated to be 6.4–14.9% for China and 8.2–22.3% for India. POD6 predicted greater RYL, especially for the warm regions of India, whereas the 90 days AOT40 gave the lowest estimates. For the future projection, all the O3 dose metrics gave comparable estimates of an increase in RYL from 2000 to 2020 in the range 8.1–9.4% and 5.4–7.7% for China and India, respectively. The lower projected increase in RYL for India may be due to conservative estimation of the emission increase in 2020. Sensitivity tests of the model showed that the PODY‐based estimates of RYL are highly sensitive to perturbations in the meteorological inputs, but that the estimated increase in RYL from 2000 to 2020 is much more robust. The projected increase in wheat production loss in China and India in the near future is substantially larger than the uncertainties in the estimation and indicates an urgent need for curbing the rapid increase in surface [O3] in these regions. 相似文献
3.
Comparison of crop yield sensitivity to ozone between open‐top chamber and free‐air experiments 下载免费PDF全文
Zhaozhong Feng Johan Uddling Haoye Tang Jianguo Zhu Kazuhiko Kobayashi 《Global Change Biology》2018,24(6):2231-2238
Assessments of the impacts of ozone (O3) on regional and global food production are currently based on results from experiments using open‐top chambers (OTCs). However, there are concerns that these impact estimates might be biased due to the environmental artifacts imposed by this enclosure system. In this study, we collated O3 exposure and yield data for three major crop species—wheat, rice, and soybean—for which O3 experiments have been conducted with OTCs as well as the ecologically more realistic free‐air O3 elevation (O3‐FACE) exposure system; both within the same cultivation region and country. For all three crops, we found that the sensitivity of crop yield to the O3 metric AOT40 (accumulated hourly O3 exposure above a cut‐off threshold concentration of 40 ppb) significantly differed between OTC and O3‐FACE experiments. In wheat and rice, O3 sensitivity was higher in O3‐FACE than OTC experiments, while the opposite was the case for soybean. In all three crops, these differences could be linked to factors influencing stomatal conductance (manipulation of water inputs, passive chamber warming, and cultivar differences in gas exchange). Our study thus highlights the importance of accounting for factors that control stomatal O3 flux when applying experimental data to assess O3 impacts on crops at large spatial scales. 相似文献
4.
Effects of elevated ozone concentration on CH4 and N2O emission from paddy soil under fully open‐air field conditions 下载免费PDF全文
We investigated the effects of elevated ozone concentration (E‐O3) on CH4 and N2O emission from paddies with two rice cultivars: an inbred Indica cultivar Yangdao 6 (YD6) and a hybrid one II‐you 084 (IIY084), under fully open‐air field conditions in China. A mean 26.7% enhancement of ozone concentration above the ambient level (A‐O3) significantly reduced CH4 emission at tillering and flowering stages leading to a reduction of seasonal integral CH4 emission by 29.6% on average across the two cultivars. The reduced CH4 emission is associated with O3‐induced reduction in the whole‐plant biomass (?13.2%), root biomass (?34.7%), and maximum tiller number (?10.3%), all of which curbed the carbon supply for belowground CH4 production and its release from submerged soil to atmosphere. Although no significant difference was detected between the cultivars in the CH4 emission response to E‐O3, a larger decrease in CH4 emission with IIY084 (?33.2%) than that with YD6 (?7.0%) was observed at tillering stage, which may be due to the larger reduction in tiller number in IIY084 by E‐O3. Additionally, E‐O3 reduced seasonal mean NOx flux by 5.7% and 11.8% with IIY084 and YD6, respectively, but the effects were not significant statistically. We found that the relative response of CH4 emission to E‐O3 was not significantly different from those reported in open‐top chamber experiments. This study has thus confirmed that increasing ozone concentration would mitigate the global warming potential of CH4 and suggested consideration of the feedback mechanism between ozone and its precursor emission into the projection of future ozone effects on terrestrial ecosystem. 相似文献
1