模拟酸雨对水稻生长与水稻土养分的影响

Effects of Simulative Acid Rain on Rice Growth and Paddy Soil Nutrient Distribution

采用温室盆栽水稻喷淋模拟酸雨实验,研究不同pH值(2.5,3.5,4.5,>5.6)的酸雨对水稻生长和水稻土养分的影响。结果表明:在酸雨的影响下,除喷淋pH 4.5酸雨外,其余酸雨处理的土壤有机质均下降了9.1%～16.7%;不同浓度的酸雨对土壤碱解氮的影响不大,但速效钾在喷淋酸雨后相对基础土样下降了33.9%左右;土壤速效磷含量相对基础土样提高了21.3%～40.5%;土壤有效硫的含量随着酸雨pH的降低而升高;喷淋酸雨后土壤中的交换性钙、镁相对基础土样分别上升了27.6%～36.3%和3%～21%。酸雨对水稻茎叶氮的吸收影响不大,但水稻稻粒中全氮的含量会随着酸雨pH的降低而升高;酸雨不利于水稻茎叶对养分磷的吸收,但pH 2.5的酸雨会促进稻粒对磷的吸收;酸雨有利于水稻茎叶对养分钾的吸收,但不利于稻粒对养分钾的吸收;水稻茎叶和稻粒中全硫的含量会随着酸雨pH的降低而升高。水稻在pH 2.5的酸雨影响下显著减产,喷淋了pH 3.5酸雨的水稻其千粒重、结实率和实粒数都是最高的,表明pH 3.5的酸雨对水稻产量的提高有一定的刺激作用。

In order to study the effects of the simulative acid rain(SAR) with different pH-value(2.5,3.5,4.5 and >5.6) on rice growth and paddy soil nutrient,a pot experiment which used paddy soil to cultivate rice in greenhouse was performed.The results showed that: under the influence of SAR,the soil organic matter content was decreased by 9.1%～16.7% except for the treatment of SAR pH 4.5;different pH-value of SAR had little effect on hydrolysable nitrogen content in paddy soil,but after spraying SAR,readily available potassium in paddy soil had decreased by 33.9% and readily available phosphorus had increased by 21.3%～40.5% in comparison with the original soil;the available sulfur in paddy soil increased along with the decreasing of pH-value of SAR;the exchangeable calcium and magnesium in paddy soil after spraying SAR had increased respectively by 27.6%～36.3% and 3%～21% in comparison with the original soil;SAR had little effect on nitrogen uptake for rice straw,but the total nitrogen content in millet increased along with the decreasing of pH-value of SAR;acid rain was not conducive to the absorption of phosphorus by rice straw,but the treatment of SAR pH 2.5 could promote the absorption of phosphorus by millet;acid rain was conducive to the absorption of potassium by rice straw but not conducive to that by millet;total sulfur in rice straw and millet increased along with the decrease of pH-value of SAR;grain yield was significantly reduced in the treatment of SAR pH 2.5;1000-grain weight,seed setting rate and filled grains per panicle were all the highest after spraying SAR pH 3.5,suggesting that the acid rain with pH 3.5 had a certain stimulative effect for the increase of rice yield.