Zhu Jianguo

Responses of Dry Matter Production and Distribution in Rice (Oryza sativa L.) to Ozone and High Nitrogen Supply

An ozone free-air control enrichment(O3-FACE) experiment was conducted in 2011 to study the effects of O3 and high nitrogen(N) supply on dry matter production and distribution of rice.Two cultivars,Shanyou 63(SY63,three-line hybrid indica cultivar) and Yangdao 6(YD6,inbred indica cultivar),were investigated.The results showed:(1) Elevated O3 concentration significantly reduced the biomass of stems and foliages in the mid-filling stage by 30.20%,21.95% for SY63 and 21.71%,11.12% for YD6,respectively,due to the significant decrease of the net photosynthetic rate.O3 exposure also significantly reduced the yield,the biomass of roots and panicles in the harvesting stage by 45.75%,48.62%,37.15% for SY63,and 28.91%,35.22%,28.01% for YD6,respectively.Increasing N supply could mitigate O3-induced reduction of the net photosynthetic rate,the dry matter and yield,where the yield and biomass of stems,foliages,roots and panicles were changed by elevated O3only by-26.88%,-13.52%,-5.84%,-26.33%,-16.19% for SY63,and-12.68%,-16.26%,+5.19%,-14.55%,-20.22% for YD6,respectively;(2) In SY63 and YD6 exposed to O3,the root-shoot ratio and root dry matter distribution in whole plant decreased significantly,and the ratio of foliage dry matter distribution increased significantly,but there was no significant effect on the ratio of stem or panicle dry matter distribution.High N supply could increase the ratio of root or foliage dry matter and the root-shoot ratio at O3-FACE treatments;(3) O3 exposure could reduce N accumulation of SY63 and YD6,which would show upward trends after high N treatments.These results implied that increasing N supply could mitigate O3-induced changes in dry matter production and distribution of SY63 and YD6.

Investigation on char cloud burning rates under oxy-combustion

Oxyfuel combustion is an effective low-carbon emission clean combustion technology and many researches focus on this novel technology research and development worldwide. Further investigation is needed on pysicochemical effects of carbon dioxide and gas water on burning rate and oxy-flame propagation, etc. The current research only focuses on the gasification effect of carbon dioxide on char burning rates under oxyfuel combustion, and discussions on the contribution of gasification from carbon dioxide to oxy-char burning rates and flame propagation in three schemes of endothermic gasification reaction from carbon dioxide, exothermic oxidation reaction from oxygen and oxyfuel crossover competing reaction. Compared with air-char combustion, the researches were carried out on oxy-char burning rates and oxy-flame propagation under moderate and high temperatures, i.e., 1273 K and 1773 K, on the novel high temperature oxyfuel combustion experimental rig. Results showed that the gasification from carbon dioxide and the oxidation from oxygen were nearly the same contribution ratio to the oxy-char maximum burning rates under moderate temperature, but this ratio was different under high temperature. In moderate temperature, the coal char maximum burning temperature was almost similar and higher than heating temperature as 27 K, and the flame propagated from outside to inside region. In high temperature, the char burning surface temperature was lower as 60 K and higher than conventional air combustion as 55 K companied with luminescence flameless propagation.

Effect of Elevated Surface O3 Concentration on Soil Microbial Functional Diversity in Wheat Field

The effect of elevated surface O3concentration(~70 nmol mol-1) on soil microbial functional diversity was investigated by determining water-solution organic carbon(WSOC) content,soil respiration intension and BIOLOG in China O3-FACE(Free-air ozone concentration enrichment) field based on a rice/wheat rotation system.The results showed that with the enhancing of O3concentration,the WSOC content,soil respiration intension and AWCD(average well colour development) were significantly increased(P0.05).Diversity indexes showed that with the enhancing of O3 concentration,Shannon and Simpson indices had no differences,but McIntosh indices was significantly increased(P0.05).The PCA results showed that the elevated O3 concentration significantly affected the soil microbial ability of utilizing glucide and better than any other substrates.This research suggested that elevated O3 concentration(~70 nmol mol-1) significantly increased soil microbial functional diversity in wheat field.