摘要
为了明确开放式空气CO2浓度增高(FACE)对水稻磷素动态的影响,借助目前国内惟一的FACE技术平台,以武香粳14为供试品种,设置不同施N量处理,研究大气CO2浓度高于对照200μmol·mol-1的FACE处理对水稻P素吸收利用动态的影响。结果表明,FACE处理使水稻各生育期P素累积量较CK显著增加,含P率也有所增加,但增幅不大。增施N肥对P素累积量及含P率均影响不大。在此基础上采用Logistic方程描述了水稻P素累积量及含P率随移栽天数的动态变化过程,并建立CO2及P素影响因子对模型进行了订正。利用建模以外的试验数据对该模型进行了检验,结果表明,模拟值与实测值之间的根均方差(RMSE)较小,相关系数达到了显著或极显著水平,表明模型的预测性能好。
The effects of increase in CO2 concentration on phosphorus dynamic of rice was studied in this paper, based on a FACE experiment conducted at Anzhen, Wuxi, Jiangsu Province in 2001--2003. The FACE facility consisted of three FACE rings （three repetitions） and five ambient rings, and the ambient rings were 90 m apart to avoid contamination of elevated CO2. Rice were grown from transplanting to harvest under two levels of [CO2] for three consecutive years, and the target [CO2] of the FACE rings was 200 μmol·mol^-1 higher than that in the ambient air. The annual mean temperature was about 16℃, the annual mean rainfall was 1 150 mm and the annual sunshine hours were 2 000 h in the experiment area. The experiment was conducted in 3 years using the japonica cultivar Wuxiangjing 14. Seeds were sowed on 18 May and seedlings were hand transplanted with 3 plants each hill on 13 June. Hills and rows were 16.7 and 30 cm apart, respectively（equivalent to 24 hill· m^-2）, and three levels of N treatment were applied ： LN （150 kg·hm^-2）, MN （250 kg·hm^-2） and HN （350kg·hm^-2）. The results in- dicated that phosphorus accumulation and phosphorus content in rice plant increased at different growth stages under FACE treatment. The model of phosphorus accumulation was described by Logistic equation and the exponential and quadratic functions were used to describe CO2 concentration effect. The phosphorus content was defined as the proportion of phosphorus accumulation to that of shoot mass. The models were described with numbers of days after transplanting and the phosphorus dynamics were fitted well both under FACE and normal conditions. The model validation using different experimental data indicated that, the RMSE between simulated and observed values was small and the correlation coefficients were significant at 5% level, suggesting that the models were accurate.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2008年第3期1009-1014,共6页
Journal of Agro-Environment Science
基金
国家自然科学基金项目(30270777、30471013)
国家自然科学基金重大国际合作研究项目(40120140817)
中国科学院知识创新重要方向项目(KZCX-2-408、KZCX3-SW-440)
关键词
水稻
FACE
P素累积量
含P率
模型
rice
free-air CO2 enrichment
phosphorus accumulation
phosphorus content
model
