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利用太湖地区农业科学研究所31年的长期肥料定位试验田,分别于2011—2012年水稻抽穗期、结实期和收获期进行了杂草群落调查,并对杂草种群分布与土壤养分因子进行冗余分析。结果表明:随着水稻的生育进程,田间杂草密度增大,而氮磷肥的配施也能有效减少试验区田间杂草的密度;牛毛毡、鸭舌草、耳叶水苋和水蕨是水稻生长期的主要杂草类型;在施入磷肥的处理中,莎草科杂草密度减少甚至消失,鸭舌草密度则增加,耳叶水苋和水蕨则是在没有施肥的处理生长最好;氮磷配施减少群落丰富度的同时能增加群落的均匀度,人为干预相对最少的处理方式有利于群落结构的稳定发展。抽穗期RDA结果显示,第1、第2排序轴特征值分别为0.901和0.080,土壤全P、有效磷、全氮、碱解氮与第1排序轴相关系数分别为-0.887、-0.816、-0.810和-0.794。太湖地区稻麦两熟制条件下,长期不同施肥方式显著影响稻田杂草的群落组成,土壤养分库的差异性影响田面杂草密度和优势种群分布,影响稻田中杂草分布的土壤养分因子主要为氮、磷和有机质,土壤钾含量对杂草的总体分布影响相对较小。
Using 31 years of long-term fertilizer experimental plots in the Institute of Agricultural Sciences of Taihu Lake, we conducted a survey of weed communities in rice heading stage, grain-filling stage and harvesting stage in 2011-2012, respectively, and weed population distribution and soil nutrient factors were redundant analysis. The results showed that the density of weeds in the field increased with the growth of rice and that the combination of N and P fertilizers could effectively reduce the density of weeds in the field. The density of bovine felts, Monochamus alternatus, The main weed types in rice growth stage; in the treatment of applying phosphate fertilizer, the density of sedges and weeds decreased or even disappeared, the density of the flowers increased, and the leaf water and water fern grew most without fertilization Good; nitrogen and phosphorus with the community to reduce the richness of the same time can increase the community evenness, the relatively minimum man-made interventions are conducive to the stable development of community structure. The results of RDA at heading stage showed that the first and second ordination axis eigenvalues were 0.901 and 0.080, respectively. The correlation coefficients of total P, available phosphorus, total nitrogen, available nitrogen and the first ordination axis were -0.887, -0.816, 0.810 and -0.794. The results showed that the long-term different fertilization modes significantly affected the community composition of weeds in paddy field. The differences of soil nutrient pool affected the density of weedy field and the distribution of dominant species, For nitrogen, phosphorus and organic matter, soil K content had a relatively small effect on the overall distribution of weeds.