Dong Hegan, Liu Tong, Liu Zhongquan, Song Zhanli
College of Life Science Shihezi University Shihezi China.
Rural Energy and Environment Work Station in Yili Yining Xingjiang China.
Ecol Evol. 2020 Apr 12;10(11):4854-4866. doi: 10.1002/ece3.6238. eCollection 2020 Jun.
Giant ragweed (, L. henceforth referred to as GR), an annual non-native invasive weed, may cause health problems and can reduce agricultural productivity. Chemical control of GR in grasslands may have irreversible side effects on herbs and livestock. In an attempt to propose a solution to the harmful effects of GR on grasslands, this study explores the fate of its soil seed bank (SSB) and considers the physical control of its SSB reduction. By studying GR distributed in grasslands of the Yili Valley, Xinjiang, China, we measured the spatial and temporal changes in seed density, seed germination, dormancy, and death. We analyzed seed germination, dormancy, and death following different storage periods. The study analyzed population characteristics over time, including seed fate, and examined physical control methods for reducing the SSB density. The SSB of GR occurs in the upper 0-15 cm of soil in grasslands. Seed density in the SSB decreased by 68.1% to 82.01% from the reproductive growth period to the senescence period. More than 98.7% of the seeds were rotten, eaten, germinated, dispersed, or died within one year after being produced. The seed germination rate of the SSB decreased with the number of years after invasion. When stored for 0.5 or 3.5 years, seed germination rates fell by 40%, during which time seed death rate increased by almost 40%. When GR was completely eradicated for two consecutive years, the SSB and population densities decreased by >99%. The vast majority of GR seeds germinated or died within one year; the germination rate decreased significantly if the seeds were stored dry at room temperature for a long time. Newly produced seeds are the main source of seeds in the SSB. Therefore, thoroughly eradicating GR plants for several years before the seeds can mature provides an effective control method in grasslands.
巨型豚草（，此后简称为GR）是一种一年生非本地入侵杂草，可能会引发健康问题并降低农业生产力。草原上对GR进行化学防治可能会对草本植物和牲畜产生不可逆转的副作用。为了试图找到解决GR对草原有害影响的办法，本研究探究了其土壤种子库（SSB）的归宿，并考虑对其SSB减少进行物理控制。通过研究分布在中国新疆伊犁河谷草原的GR，我们测量了种子密度、种子萌发、休眠和死亡的时空变化。我们分析了不同储存期后的种子萌发、休眠和死亡情况。该研究分析了随时间变化的种群特征，包括种子归宿，并研究了降低SSB密度的物理控制方法。GR的SSB存在于草原土壤上层0至15厘米处。从生殖生长期到衰老期，SSB中的种子密度下降了68.1%至82.01%。超过98.7%的种子在产生后一年内腐烂、被吃掉、萌发、扩散或死亡。SSB的种子萌发率随着入侵年份的增加而降低。储存0.5年或3.5年后，种子萌发率下降了40%，在此期间种子死亡率几乎增加了40%。当连续两年彻底根除GR时，SSB和种群密度下降超过99%。绝大多数GR种子在一年内萌发或死亡；如果种子在室温下长时间干燥储存，萌发率会显著下降。新产生的种子是SSB中种子的主要来源。因此，在种子成熟前连续几年彻底根除GR植株是草原上一种有效的控制方法。
