安徽沿江圩丘农区夏收作物田杂草群落分布规律的研究

ON THE DISTRIBUTION PATTERN OF WEED COMMUNITIES OF SUMMER CROP FIELDS IN RIVER VALLEY AND HILLY LANDS OF ANHUI PROVINCE

作者创用了七级目测调查取样,进行数量分析的方法,对夏收作物田杂草群落进行分类研究,揭示了安徽沿江圩丘农区夏收作物田杂草群落的分布规律主要受土壤类型和轮作制度制约。看麦娘杂草群落分布于水稻土田,猪殃殃,野燕麦杂草群落分布于丘岗区旱地,卷耳、婆婆纳杂草群落分布于灰潮土旱地。首次提出综合草害指数,用以评定杂草群落类型中每种杂草的危害性,从而,提出了不同土壤类型和轮作制度的田块中恶性杂草的定量化指标与防除策略。

Weed communities are classified with the quantitative analysis so as to avoid some possible subjective factors in the classification, description and distribution of weed communities; therefore, it is possible in this way to make the study comprehensively, objectively and quantitatively.In summer crop field; of river valleys and hilly lands of Anhui Province, 74 sampling fields were chosen to take 10 sampling plots, i.e. 10 plots were randomly selected from these fields. Transformed into overall values, the data collected by eyesight of weed damages to crops in seven scales were analysed with the fuzzy cluster. On the basis of ecological factors and community features of the sampling sites, the degree of confidence was selected and the sampling sites were classified into various clusters. The result showed that the distribution of weed communities in rape and wheat fields of the said areas is restrictly influenced by crop rotation systems and soil types. The distribution pattern of weed communities was described as follows: the Cerasltum viscosum+Veronica persica association is in the grey muddy soil dry lands of the rotation of wheat (or rape) and cotton; the Galiurn aparine var. tenerum+Avena fatua association, in the yellow-red earth or yellow-brown earth dry lands of the rotation of wheat and sweet potato (or soybean or cotton); the Alopecurus aequalis association, in the rice soil fields of the rotation of rape and rice. In order to evaluate the weed damage degree to a crop in a type of weed community, the overall weed damage index (OWDI) was first developed. As a result, the worst weeds in the fields of different crop rotation systems and soil types were determined quantitatively in accordance with this index. Finally, the strategy for integrated control of the worst weeds was suggested.The formula of the overall value and the overall weed damage index (OWDI) isOverall Value=∑(Number of a scale's·Value of the scale occupying fields)/50OWDI=∑(Number of a seale's occuppying. Value of the scale fields)/Total number of fields of·Value of the highest weed community cluster scale