集约化稻田养分均衡调控研究

在中国东南地区稻田,养分的非均衡化和高强度的投入引起稻田土壤质量退化、水体富营养化等环境问题。通过田间试验研究了不同施肥量对集约化稻田水稻叶片SPAD值、产量、养分含量、养分利用效率的影响。结果表明:水稻叶片SPAD值随施氮量的增加而增加,不同生育期SPAD值差异显著,分别为分蘖期＞抽穗期＞灌浆期。在N,K肥不同水平的处理下,水稻产量有明显的变化,并得出施用N,K肥的阈值,即在施氮处理225 kg/hm²和施钾处理180 kg/hm²水平下水稻的产量达到最大值,而磷肥施用增产效果不显著,这可能与该地土壤速效磷的含量较高有关。

The coordinated regulation of nutrients in intensive paddy field

In the paddy fields of Southeast China, the non-equilibrium and superfluous inputs of nutrients resulted in several environmental problems such as soil quality degradation, water eutrophication and so on. In this study, the effects of different fertilizer levels on the SPAD values of rice leaves, rice yield, nutrient content and nutrient use efficiency in intensive paddy field were investigated. The results showed that the SPAD values of rice leaves increased with the increasing levels of nitrogen, and the SPAD values showed significant difference in different growth stages as tillering stage＞heading stage＞filling stage. The yield of rice varied significantly under different levels of N and K fertilization, and the optimal N and K fertilizer levels were 225 and 180 kg·hm^-2 respectively, but the rice yield did not significantly increase under the application of phosphate fertilizer, which might be due to the higher level of available P in the paddy field．