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定量分析了被废弃4年、9年和14年的农田地上派生的次生林土壤中种子组成和密度,从而检测在次生林演替形成过程中,土壤种子库是否能随着植物种群的集成而集成。分别在废弃了4年、9年和14年的农田地里(15cm×15cm样方、9cm土层深),掘取了18,37和48份土壤样品。在废弃了4,9和14年的农田地上,分别发现了3,5和9个物种。在这些不同的生命形态中,在9年和14年的迹地上,土壤种子树木占主要成分,分别为60%和33%,而4年废弃迹地主要被非木本植物所占领。三块废弃地里,4年废弃迹地植物种子的总数为327粒,相应可发育的种子密度为141粒/m2,14年废弃迹地种子的总数为46粒,相应的可发育种子的密度为26粒/m2,指明种子数、种子密度随废弃地龄成下降趋势。在9年和14年龄废弃地上,土壤种子植物种类与立地木本植物种类的相似度较低,而4年龄地上两者比较则完全不同。我们认为:土壤种子库的物种构成是在次生演替过程中逐渐形成的,但是,所获得的总体种子密度太低,仅仅依赖于这些种子来实现树木自然再生是不可靠的。为了加快这些废弃地次生林的恢复,既要依靠自然集成的土壤种子库,还需要通过直播、所需物种的强化种植和设定人工生长环境以利于种子传播。
The composition and density of the seed in the secondary forest soils that had been abandoned for 4 years, 9 years and 14 years were quantitatively analyzed to determine whether the soil seed bank can be integrated with the plant population during the succession of secondary forest succession. 18, 37 and 48 soil samples were excavated from farmland (15 cm × 15 cm quadrats, 9 cm soil depth) abandoned for 4 years, 9 years and 14 years respectively. On the farmland abandoned for 4, 9 and 14 years, 3,5 and 9 species were found, respectively. Of these different forms of life, soil seed trees account for 60% and 33% of the total soil for 9 years and 14 years respectively, whereas the 4 years of abandoned land are mainly occupied by non-woody plants. In the three abandoned areas, the total number of plant seeds in four years of abandoned land was 327 grains with a correspondingly developable seed density of 141 grains / m2, with a total of 46 grains per year for 14 years and a corresponding densifiable density of 26 Grain / m2, indicating the number of seeds, seed density with the age of waste into a downward trend. At the 9-year and 14-year-old abandoned land, the similarity of the soil seed plant species to the native woody plant species was low, while the 4-year-old and the ground-floor comparisons were quite different. In our opinion, the species composition of soil seed bank is gradually formed during the secondary succession. However, the total seed density obtained is too low. It is unreliable to rely solely on these seeds for natural regeneration of trees. In order to speed up the recovery of secondary forests in these abandoned areas, we need to rely not only on naturally integrated soil seed banks, but also through direct seeding, intensive planting of the species in need, and establishment of artificial growth environments to facilitate seed dispersal.