南京地区稻田土壤杂草种子库的数量特征及演替规律

通过对南京地区稻田土壤杂草种子库4年的调查,试图探明该地区稻田土壤杂草种子库中杂草种子的种类、数量、垂直分布情况及这些数量特征逐年演替的动态规律.研究表明:在一个内外环境相对稳定的开放稻田系统中,土壤杂草种子库的种子种类约为10种左右,并有逐年减少的趋势;种子库数量1 m2耕层(20 cm)约为(104～105)粒,并有逐年增加的趋势;杂草种子的分布主要以0～10 cm的浅土层为主,并有逐年向浅土层集中的趋势.着重讨论了稻田5种优势杂草种子数量及比例变化的原因,提出了相应的控草策略和措施.

Species, Population, Vertical Distribution and Succession Regularity of Weed Seedbank in Nanjing Paddy Fields

By 4 years researches,species,population as well as vertical distribution of weeds seedbank in Nanjing paddy fields,and succession regularity of these quantitative characteristics were brought forward.The results revealed that in a steady environment system of paddy field,the number of seedbank species was about 10,and tended to reduce year by year.The population of seedbank in 1 m2 top soil(20 cm) was 104-105 grain,and tended to increase gradually.Weed seeds were mostly distributed in 0-10 cm soil,and were centralized to the surface layer more and more.Based on the analysis of the cause of changes in seed quantity and proportion of 5 dominant weeds,measures to control weed was put forward.