双季稻栽培方式对冬闲期杂草生长及土壤养分含量的影响

于2009～2011年,在湖南长沙进行双季稻不同栽培方式（＂三定＂栽培、免耕摆栽、传统栽培）定位试验,研究了双季稻不同栽培方式对冬闲期稻田杂草生长及土壤养分含量的影响。结果表明：与传统栽培相比,＂三定＂栽培和免耕摆栽方式下冬闲期杂草的密度、单株干重和单位面积生物量以及土壤表层（0～5cm）的碱解氮、有效磷和速效钾含量均较高。其中,冬闲期杂草单位面积生物量、单株干重、单位面积密度与土壤表层碱解氮含量呈显著正相关关系,说明冬闲期杂草在双季稻稻田土壤养分循环中起了重要的作用。

Effects of Different Rice Cultivation Patterns on Fallow Weed Growth and Soil Nutrient Contents in A Double Rice Cropping System

To determine the effects of different rice cuhivation patterns on fallow weed growth and soil nutrient contents in double rice cropping system, a field experiment with three rice cultivation patterns （ ＂Sanding＂ cultivation, no - tillage and seedling broadcasting and traditional cultivation） was conducted in Changsha, Hunan Province during 2009 -2011. Results showed that density, dry weight per plant and biomass per unit land area of fallow weeds as well as contents of al- kali -hydrolyzable nitrogen, available phosphorus and available potassium in the surface soil layer （0 -5 era） were higher under ＂Sanding＂ cultivation and no - tillage and seedling broadcasting than under traditional cultivation. Furthermore, significant relationships were found between density, dry weight per plant and biomass per unit land area of fallow weeds with alkali -hydrolyzable nitrogen content in the surface soil layer, which indicates that fallow weeds may play an impor- tant role in soil nutrient cycling in the double rice cropping system.