轻型栽培技术对稻田潜杂草群落多样性的影响

为明确轻型栽培技术对稻田潜杂草群落多样性的影响,研究了旱直播、水直播、抛秧、机插秧、麦套稻5种轻型栽培稻作模式及传统手插秧模式下稻田杂草种子库的数量特征.结果表明：旱直播稻田种子库密度显著高于其他模式,达228416粒·m^-2,麦套稻模式其次.另外,旱直播稻田莎草类杂草与麦套稻稻田阔叶类杂草种子密度显著高于其他模式的各类杂草种子.传统手插秧稻田具有最高的物种丰富度,Margalef指数达1.86; 麦套稻与水直播模式中,Shannon-Wiener指数、Gini指数、Pielou群落均匀度指数明显高于旱直播和机插秧等模式.与传统手插秧相比,各轻型栽培稻作模式具有不同的潜杂草群落优势种.为防治稻田杂草的持续危害,应轮流实施不同轻型栽培稻作模式.

Effects of labor-saving rice cultivation modes on the diversity of potential weed communities in paddy fields

Aimed to understand the effects of various labor-saving rice cultivation modes on the diversity of potential weed communities in paddy fields,an investigation was made on the quantitative characteristics of the weed seed bank under dry direct seeding,water direct seeding,seedling throwing,mechanized-transplanting,wheat-rice interplanting,and conventional manual transplanting.Under dry direct seeding,the density of the weed seed bank was up to 228416 seeds·m~(-2),being significantly higher than that under the other five cultivation modes.Wheat-rice interplanting ranked the second place.The seed density of sedge weeds under dry direct seeding and that of broad leaf weeds under wheat-rice interplanting were significantly higher than the seed densities of various kinds of weeds under other cultivation modes.Conventional manual transplanting mode had the highest species richness,with Margalef index being 1.86.The diversity indices,including Shannon-Wiener index,Gini index,and Pielou evenness index under water direct seeding and wheatrice interplanting were higher than those under other cultivation modes.Comparing with conventional manual transplanting mode,the other five cultivation modes had their own dominant species in the potential weed community,and thereby,different labor-saving rice cultivation modes should be applied by turns to control the potential weed community in paddy fields effectively and persistently.