摘要
田间试验研究了早稻套萍对降低稻田表面水养分浓度、增加水稻产量和土壤肥力的影响。结果表明:稻田套萍能够有效降低表面水总氮、总磷的浓度,7d内总氮去除率为30.0%,总磷去除率为56.8%;同时,水稻的成穗率、穗实粒数和结实率得到提高,产量也大有增加。根据监测期间红萍的平均氮磷含量、日增长速度以及稻田基肥施用后表面水总氮和总磷浓度计算,套种红萍约需46d和12d可完全消纳表面水中的氮和磷;稻田套萍前期可通过吸收表面水中的氮磷而降低稻田土壤表层有效氮磷养分,后期倒萍则能迅速为水稻提供养分,有利于水稻后期的生长发育和减少稻田氮磷流失。
The effects of Azolla spp. culture with early rice on decreasing of nutrient concentration of surface water in paddy field, increasing rice yield and soil fertility were studied by field experiments. The results showed that Azolla spp. culture in paddy field could effective｜y decrease the concentrations of total nitrogen and total phosphor in surface water, the removal efficiencies of total nitrogen and total phosphor within one week were 30.0% and 56.8%, respectively; the productive tiller rate, grain number per panicle and seed setting rate of rice increased and the rice yield increased greatly. According to the average content of nitrogen and phosphor, diurnal growth rate of AzoUa spp. and the concentration of total nitrogen and total phosphor in surface water that after applied base fertilizer to paddy field, the Azolla spp. need about 46 days and 12days to completely absorb the nitrogen and phosphor in water, respectively; at the early stage, the Azolla spp. will absorb the nitrogen and phosphor in surface water to reduce the contents of effective nitrogen and phosphor in paddy field surface, and at the late stage, the Azolla spp. could quickly provide the nutrition for rice to benefit the growth of rice and reduce the loss of nitrogen and phosphor in paddy field.
出处
《湖南农业科学》
2010年第1期16-18,共3页
Hunan Agricultural Sciences
基金
国家支撑计划课题(2007BAD87B11)
湖南省农科院创新基金(2009hnnkycx32)
关键词
红萍
稻田套萍
稻田表面水
产量
土壤肥力
Azolla spp
Azolla spp. culture in paddy field
surface watei in paddy field
yield
soil fertility
