Deposition of exotic bird-dispersed seeds into three habitats of a fragmented landscape in the northeastern United States
Deposition of exotic bird-dispersed seeds into three habitats of a fragmented landscape in the northeastern United States
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外来鸟类传播的种子沉积到美国东北部破碎景观的三个栖息地
DOI：
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发表时间：
2009
期刊：
影响因子：
1.7
通讯作者：
Jessica L. Czajka
中科院分区：
文献类型：
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作者：
T. McCay;Deanna H. McCay;Jessica L. Czajka
食果鸟类的传播促进了许多外来植物的入侵。我们测量了一个支离破碎的景观，美国东北部的三个栖息地的鸟鸣本地和外来植物的种子雨1年。我们研究了枫山毛榉林、老田地和废弃的针叶树种植园。在所有地点，我们收集了2,196颗鸟播植物种子，包括6个外来物种和10个本地物种的种子。大部分（90%）收集的种子来自外来物种。种子传播的栖息地之间大致相似，虽然种子雨的外来物种是较高的老领域比森林栖息地。种子雨没有强烈的影响，人工栖息地的大多数物种。然而，外来物种的种子更常见于旧田里人工栖木下的陷阱中。种子雨为异国情调的胡颓子，鼠李，蔷薇多花与当地的成熟植物的密度呈正相关。种子雨R. cathartica是正相关的丰富的幼苗，但不树苗，这表明后扩散死亡率是重要的。外来植物黄藤种子的传播。在所有生境中的含量都很高，占所有种子的66%。除了黑果苔属物种之外，常见外来入侵种的种子雨受种源丰富程度的影响，通过对当地结果植物的清除可有效控制外来入侵种。已广泛侵入我们地区的黑果苔草的果实显然是食果动物饮食中的常见成分。
Dispersal by frugivorous birds facilitates invasion by many exotic plants. We measured the seed rain of ornithochorous native and exotic plants at three habitats of a fragmented landscape of the northeastern United States for 1 year. We studied maple-beech forests, old fields, and abandoned conifer plantations. Across all sites we collected 2,196 ornithochorous seeds, including seeds from six exotic species and 10 native species. The majority (90%) of collected seeds were from exotic species. Seed dispersal was broadly similar among habitats, though seed rain of exotic species was higher in old fields than forested habitats. Seed rain was not strongly influenced by artificial perches for most species. However, seeds of exotic species were more commonly found in traps under an artificial perch in old fields. Seed rains for the exotic Elaeagnus umbellata, Rhamnus cathartica, and Rosa multiflora were positively associated with local density of mature plants. Seed rain of R. cathartica was positively associated with abundance of seedlings but not saplings, suggesting that post-dispersal mortality was important. Seed dispersal of the exotic Lonicera spp. was high in all habitats, accounting for 66% of all seeds collected. With the exception of Lonicera spp., seed rain of common exotic invaders was affected by the abundance of seed sources, and these species might be effectively controlled by elimination of local fruiting plants. Fruits of Lonicera morrowii, which has extensively invaded our area, are apparently a common component in the diet of frugivores.