Survival and growth of tree seedlings in relation to changes in the ground flora during natural regeneration of an oak shelterwood
Survival and growth of tree seedlings in relation to changes in the ground flora during natural regeneration of an oak shelterwood
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橡树防护林自然更新过程中树苗的生存和生长与地面植物区系变化的关系
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
M. Robertson
中科院分区：
文献类型：
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作者：
R. Harmer;R. Boswell;M. Robertson
总结的发展地面flora，存活率和高度生长的树苗，每年观察超过5年的期间，在英格兰南部的橡树林地的最大的一年。在移除矮林下层并使树冠变薄以留下60- 70%的覆盖率之后，地面花卉迅速发展，其中主要是树莓（树莓），尽管蕨（蕨）的频率和数量随着时间的推移而增加。超过10个木本物种再生，但只有三个，栎（橡树），白蜡（灰）和白桦（桦树），被发现在大量。许多桦树和榛（榛子）幼苗生长得很好，足以出现在荆棘和欧洲蕨之上;相反，2年后，很少有橡树和白蜡树比荆棘高，没有一棵比欧洲蕨高。橡树和白蜡树幼苗的数量与母树的数量和接近程度呈正相关。幼苗种群大小的减少与植被的类型、数量和高度之间没有一致的关系。幼苗种群的规模一般随着时间的推移而下降，每年减少0%至90%不等，视物种和年份而定;在大多数研究中，橡树和白蜡树种群每年减少40%至50%。苗高与立地条件之间存在一定的相关性，但相关性不一致，且因树种和年份而异。结果进行了讨论有关的天然更新橡木。
Summary The development of the ground fl ora, and survival and height growth of tree seedlings, were observed annually over the 5-year period following a mast year in an oak woodland in southern England. After removal of the coppice understorey and thinning of the tree-canopy to leave 60–70 per cent cover there was a rapid development of the ground fl ora which was dominated throughout by Rubus fruticosus (bramble), although the frequency and amount of Pteridium aquilinum (bracken) increased with time. More than 10 woody species regenerated but only three, Quercus robur (oak), Fraxinus excelsior (ash) and Betula pendula (birch), were found in substantial amounts. Many birch and Corylus avellana (hazel) seedlings grew suffi ciently well to emerge above the bramble and bracken; in contrast, after 2 years few oak and ash were taller than the bramble and none were taller than the bracken. The number of oak and ash seedlings was positively related to the number and proximity of parent trees. There were no consistent relationships between decreases in the sizes of the seedling populations and the type, amount and height of vegetation. The size of seedling populations generally declined with time with annual reductions varying from 0 to 90 per cent depending on species and year; for most of the study, oak and ash populations fell by 40–50 per cent each year. There were some signifi cant relationships between seedling height and site characteristics but these were inconsistent, varying between tree species and year. Results are discussed in relation to the natural regeneration of oak.