Tree and shrub seed dispersal in pastures: The importance of rainforest trees outside forest fragments
Tree and shrub seed dispersal in pastures: The importance of rainforest trees outside forest fragments
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牧场中树木和灌木种子的传播：森林碎片之外的雨林树木的重要性
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
Graciela Sánchez
中科院分区：
文献类型：
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作者：
J. Laborde;S. Guevara;Graciela Sánchez
摘要热带牧场的森林恢复受到种子传播的限制，主要是因为木本植物的种子传播者避开森林砍伐区。在墨西哥的洛斯塔斯特拉斯，我们用隔离的无花果树围了起来，这些无花果树是为了给牧场提供阴凉而留下的。我们监测种子沉积在他们的树冠下超过一年，并采样建立植被后3年。分散距离估计捕获的种子和建立的植物，假设最近的同种成人扎根在75米的无花果树的母亲。在种子雨中捕获了70种乔木和灌木，累积密度为833粒·m−2。y−1。经过3年的发展，共建立了77种乔木和灌木（密度为4.0株·m-2）。直径小于7毫米的种子经常散布在牧场上超过75米的距离上。较大的种子分散在较短的距离和较低的数量，但一旦他们到达孤立的无花果树，发芽和建立成功率高于小种子。隔离在牧场的雨林树木作为再生核，具有催化和加速次生演替的巨大潜力。由于其地理位置，它们也是森林恢复的极其重要的种子来源，只要它们被授粉者和种子传播者访问。
Abstract Forest recovery in tropical pastures is limited by seed dispersal, mainly because the seed dispersers of woody plants avoid deforested areas. In Los Tuxtlas, Mexico, we fenced in isolated fig trees that had been left to provide shade in pastures. We monitored seed deposition under their canopies over a year and sampled the established vegetation after 3 y. Dispersal distances were estimated for captured seeds and established plants, assuming that the nearest conspecific adult rooted within 75 m of the fig tree was the mother. Seventy tree and shrub species were captured in seed rain, with a cumulative density of 833 seeds·m−2.-y−1. After 3 y, 77 species of trees and shrubs had established (density: 4.0 plants·m−2). Seeds < 7 mm in diameter were frequently dispersed over distances greater than 75 m across the pasture. Larger seeds were dispersed over shorter distances and in much lower numbers, but once they had arrived at the isolated fig trees, germination and establishment success was higher than it was for small seeds. Rainforest trees isolated in pastures have an enormous potential for catalyzing and accelerating secondary succession by acting as regeneration nuclei. Because of their location, they are also extremely important seed sources for forest recovery, provided that they are visited by pollinators and seed dispersers.