摘要
采用FACE(FreeAirCarbon dioxideEnrichment)技术 ,研究了不同N、P施肥水平下 ,水稻分蘖期、拔节期、抽穗期和成熟期根、茎、叶、穗生长 ,C/N比 ,N、P含量及N、P吸收对大气CO2 浓度升高的响应 .结果表明 ,高CO2 促进水稻茎、穗和根的生长 .增加分蘖期叶干重 ,对拔节期、抽穗期和成熟期叶干重没有显著增加 .降低茎、叶N含量 ;增加抽穗期穗N含量 ,降低成熟期穗N含量 ;对分蘖期根N含量影响不显著 ,而降低拔节期、抽穗期和成熟期根N含量 .增加拔节期、抽穗期和成熟期叶P含量 ,对茎、穗、根P含量影响不显著 .水稻各组织C含量变化不显著 .C/N比增加 .显著增加水稻地上部分P吸收 ;增加N吸收 ,但没有统计显著性 .N、P施用对水稻各组织生物量没有显著影响 .高N(HN)比低N(LN)增加组织中N含量 ,而不同P肥水平间未表现出明显差异 .高N条件下高CO2 增加水稻成熟期地下部分 /地上部分比 .文中还讨论了高CO2 对N、P含量及地下部分 /地上部分比的影响机制 .
FACE (Free-air Carbon Dioxide Enrichment) was used to study the effects of elevated CO 2 on rice (Oryza sativa) growth,tissue C/N,N and P concentration and uptake at different development stages under two N and two P levels. Results showed that elevated CO 2 increased dry matter accumulation in rice stem, ear and root. Leaf dry matter was increased at tillering stage and no significant effect was found at jointing, heading and ripening stages. N concentration of stem and leaf was decreased. Ear N concentration at heading stage was increased but was decreased at ripening stage. No significant effect was found on root N concentration at tillering stage but root N concentration at jointing, heading and ripening was decreased. Leaf P concentration at jointing, heading and ripening was increased but no significant effect was found on P concentration in stem, ear and root. C content in various tissues changed unremarkably and the ratio of C over N (C/N) was increased. Elevated CO 2 significantly increased P uptake in aboveground tissues; and increased N uptake, but the difference was not statistically significant. N and P fertilization had no significant effect on various tissue dry biomass. Tissue N content at higher N fertilization was higher than at lower N fertilization but no such effect of P fertilization on tissue P content was found. At higher N fertilization, elevated CO 2 increased the ratio of below-ground biomass over above-ground biomass at ripening stage. Possible reasons are discussed for the differences of tissue N and P content and the ratio of below-ground biomass over above-ground biomass between elevated and ambient atmospheric CO 2 concentrations.
出处
《应用生态学报》
CAS
CSCD
2002年第10期1223-1230,共8页
Chinese Journal of Applied Ecology
基金
中国科学院知识创新重要方向项目 (KZCX2 40 8)
国家自然科学基金重大国际合作研究资助项目 (4 0 12 0 14 0 817) .
