模拟酸雨对福州沿江稻田水稻叶片碳氮磷含量及其生态化学计量学特征的影响

为阐明酸雨对早、晚稻叶片不同时期碳(C)、氮(N)、磷(P)含量及其生态化学计量学特征的影响,设置对照(Control,CK)、pH4.5、pH3.5酸雨处理,对福州沿江稻田早、晚稻叶片不同时期C、N、P含量及其生态化学计量学特征进行测定和分析。研究结果表明:早稻叶片C、N、P含量在拔节期和成熟期分别为(401.08±1.83)、(37.01±2.54)、(1.01±0.05) g/kg和(349.08±4.52)、(15.52±0.05)、(0.48±0.01) g/kg,晚稻C、N、P含量在拔节期和成熟期分别为(389.00±2.82)、(28.52±0.31)、(0.74±0.01) g/kg和(317.25±1.65)、(8.18±0.51)、(0.29±0.03) g/kg,早稻叶片养分含量整体显著高于晚稻(P0.05),且各处理拔节期养分含量均显著高于成熟期含量(P0.05),整体上,酸雨处理可显著降低早稻叶片在拔节期的C、N、P含量(P0.05)。早稻叶片C/N、C/P、N/P在拔节期和成熟期分别为(10.94±0.77)、(400.13±18.91)、(36.77±2.07)和(23.19±0.63)、(737.04±30.47)、(32.08±1.03),晚稻叶片C/N、C/P、N/P在拔节期和成熟期分别为(13.74±0.26)、(528.10±0.26)、(38.70±0.74)和(39.61±2.11)、(1148.97±103.82)、(28.90±1.27),整体上,晚稻叶片各项比值高于早稻,根据各处理之间叶片的N/P值发现,模拟酸雨并未改变水稻P限制现状,在水稻生长的过程中,尤其是在拔节期需要追施适量的磷肥。

Effects of simulated acid rain on carbon, nitrogen, phosphorus contents and the ecological stoichiometry of rice leaves in Fuzhou rice fields along the river

In order to clarify the effects of acid rain on carbon (C), nitrogen (N), phosphorus (P) contents and ecological stoichiometry of riceleaves, we set the control (CK), pH4.5 and pH3.5 acid rain treatments. C, N and P contents and their ecological stoichiometry were measured and analyzed in different rice growth stages in the paddy field of Fuzhou rice fields along the river. The results showed that the carbon, nitrogen and phosphorus contents in early rice leaves were 401.08±1.83 g/kg, 37.01±2.54 g/kg, 1.01±0.05 g/kg during rice jointing stage and 349.08±4.52 g/kg, 15.52±0.05 g/kg, 0.48±0.01 g/kg during maturity stage. The carbon, nitrogen and phosphorus contents in late rice leaves were 389.00±2.82 g/kg, 28.52±0.31 g/kg, 0.74±0.01 g/kg during rice jointing stage and 317.25±1.65 g/kg, 8.18±0.51 g/kg, 0.29±0.03 g/kg during maturity stage. The nutrient content of early rice leaves was higher than that of the late rice (P<0.05), and the nutrient content in the jointing stage was higher than that in the mature stage (P<0.05). On the whole, the carbon, nitrogen and phosphorus contents of early rice leaves were decreased by the acid rain treatment during the jointing stage (P<0.05). The C/N, C/P, and N/P ratios in early rice leaves were 10.94±0.77, 400.13±18.91, 36.77±2.07 during rice jointing stage, and 23.19±0.63, 737.04±30.47, 32.08±1.03 during the maturity stage. The C/N, C/P, and N/P ratios in late rice leaves were 13.74±0.26, 528.10±0.26, 38.70±0.74 during rice jointing stage, and 39.61±2.11, 1148.97±103.82, 28.90±1.27 during the maturity stage. On the whole, the ratio of late rice leaves were higher than that of the early rice. According to the N/P ratio among treatments, the status of rice phosphorus limitation was not changed. It is necessary to apply proper amount of phosphate fertilizer in rice growth, especially during the jointing stage.