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对新疆干旱区分布的濒危物种大赖草的种子雨及土壤种子库动态进行了研究。结果表明,大赖草的种子8月上旬成熟,散落从8月中旬一直持续到10月初,散落的高峰期集中在9月上旬。种子成熟后因自身重力多集中于母株附近,同时还受风向、地形和天气等因素的影响;种子雨共采集到种子457粒,仅有18.6%为成熟饱满种子。土壤种子库中秋、春两季在0～2cm层中分布的种子数量分别占总种子数的80.5%和58.0%,其余种子分布在2～6cm层。土壤种子库中的种子数量受大赖草的个体分布、周围植被的密度、地形等诸多因素的影响;秋、春两季共得到种子分别为108粒、62粒,其中成熟饱满种子仅为24粒、4粒,各占总种子数的22.22%和6.45%。大赖草生长环境恶劣、种子雨及土壤种子库中种子从数量到质量均较差,严重影响了大赖草种群的自然更新。
The dynamics of seed rain and soil seed bank of Larvae, an endangered species distributed in the arid region of Xinjiang, was studied. The results showed that the seeds of Larvae mature in early August mature, scattered from mid-August until early October, the concentration of scattered concentrated in early September. After maturity, the seeds were concentrated in the vicinity of the mother plants due to their own gravity. Influenced by wind direction, topography and weather, seed rain collected 457 seeds and only 18.6% were mature and full seeds. The number of seeds distributed in 0 ~ 2 cm layer in the soil seed bank in mid autumn and spring accounted for 80.5% and 58.0% of the total number of seeds, respectively, while the remaining seeds distributed in 2 ~ 6cm layer. The number of seeds in the soil seed bank was influenced by many factors such as the individual distribution of Larvae, the density of the surrounding vegetation, topography and so on. In autumn and spring, the seeds were 108 and 62 seeds respectively, of which only 24 Grain, 4 grains, each accounting for 22.22% and 6.45% of the total number of seeds. Larix grows poorly in harsh environment. Seed rain and soil seed bank are poor in quality and quantity, seriously affecting the natural regeneration of Larvae population.