Fuentes Eduardo R, Hoffmann Alicia J, Poiani Aldo, Alliende María C
Facultad de Ciencias Biológicas Pontificia Universidad Católica de Chile, Casilla 114-D, Santiago, Chile.
Oecologia. 1986 Sep;68(3):358-366. doi: 10.1007/BF01036739.
Previous studies have shown that in Chile the so called mature matorral can have the form of either a continuous matrix of shrubs (wet sites) or of multispecific clumps of shrubs (dry sites). After clearing, sites are known to be initially covered by annuals and then byBaccharis spp. orAcacia caven shrubs. Further vegetation changes are still not documented. In the first part of this contribution we show evidence indicating that the "seed rain" of plants dispersed by birds is important only around bird perches and that in general "seed shadows" of mature matorral shrubs are small. These results suggest that late recolonization of cleared areas occurs by a slow diffusion process in which the presence of perching sites for birds plays a significant role. Then we exhibit results regarding the importance of seasonal droughts and European rabbits in explaining transitions between the various types of plant cover. Here we conclude that nursing by older shrubs and not by rocks or fallen branches, is a requirement to insure the survival of seedlings belonging to mature matorral shrubs. Nurses are important regarding both summer desiccation and herbivory. These nurse effects seem to be more important at dry sites where rabbits are also more numerous, than at wet sites where conditions seem somewhat milder and vegetation change could be faster. In the last part we discuss a scheme of vegetation change that incorporates these processes and explains the relation between them, the vegetation types and the recolonization of wet and dry areas. Finally, a brief mention is made to the difference between these processes and the comparable ones in the California chaparral.
先前的研究表明，在智利，所谓的成熟马托拉尔植被可以呈现出两种形式，一种是由灌木组成的连续基质（湿地），另一种是多物种灌木丛（旱地）。在清理之后，已知这些地点最初被一年生植物覆盖，然后被巴卡里斯属植物或卡文相思灌木覆盖。进一步的植被变化仍未被记录。在本论文的第一部分，我们展示了证据，表明鸟类传播的植物“种子雨”仅在鸟类栖息处周围才重要，而且一般来说，成熟马托拉尔灌木的“种子阴影”很小。这些结果表明，清理区域的后期重新定殖是通过一个缓慢的扩散过程发生的，其中鸟类栖息处的存在起着重要作用。然后，我们展示了关于季节性干旱和欧洲野兔在解释不同类型植物覆盖之间转变的重要性的结果。在这里，我们得出结论，确保成熟马托拉尔灌木幼苗存活的必要条件是由 older 灌木而非岩石或 fallen 树枝提供的保护。保护对于夏季干燥和食草作用都很重要。这些保护作用在兔子数量也更多的干旱地区似乎比在条件似乎较为温和且植被变化可能更快的湿地地区更为重要。在最后一部分，我们讨论了一个植被变化方案，该方案纳入了这些过程，并解释了它们之间的关系、植被类型以及湿地和旱地的重新定殖。最后，简要提及了这些过程与加利福尼亚丛林中类似过程之间的差异。
原文中“older”和“fallen”可能有误，结合语境推测可能是“older”为“older”（老的），“fallen”为“fallen”（倒下的）。
