Age structure of Juniperus communis L. In the Iberian peninsula:: Conservation of remnant populations in Mediterranean mountains
Age structure of Juniperus communis L. In the Iberian peninsula:: Conservation of remnant populations in Mediterranean mountains
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DOI：
10.1016/s0006-3207(98)00059-7
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发表时间：
1999-02-01
影响因子：
5.9
通讯作者：
Gómez, JM
中科院分区：
文献类型：
--
作者：
García, D;Zamora, R;Gómez, JM
研究了西班牙南部地中海高山地区杜松种群的人口结构，分析了其种群活力。为此，我们将这些地中海人口的年龄结构与西班牙北部（大西洋）人口的年龄结构进行了比较，并在局部范围内，将内华达山脉不同栖息地的人口进行了比较。西班牙北部的人口在年轻阶段显示出高比例的年龄结构。相比之下，地中海种群被证明以成年和衰老个体为主，除了夏季水分供应较高的少数生境，幼苗和幼鱼的比例较大。干燥生境的幼苗成活率低于湿润生境，主要原因是夏季干旱。大西洋和地中海种类之间的差异以及内华达山脉生境之间的差异都反映了夏季干旱造成的气候压力严重限制了地中海山区柽柳的繁殖。地中海人口提供了一个明显的残余动态例子，由于个体寿命长，部分抵消了不利环境条件造成的损失，因此存活了很长时间。在人为干扰后恢复的能力较低，强调了保护西班牙东南部柽柳种群的必要性。1998爱思唯尔科学有限公司版权所有。
We examined the demographic structure of Juniperus communis L. populations in the Mediterranean high mountains of southern Spain in order to analyse its population viability. For this, we compared the age structure of these Mediterranean populations with those of northern Spain (Atlantic), and, on a local scale, the populations of different habitats within the Sierra Nevada. The populations from northern Spain showed age structures with high proportions at young stages. In contrast, the Mediterranean populations proved to be dominated by adult and senescent individuals, except for the few habitats with higher water availability during the summer, which have larger proportions of seedlings and juveniles. Dry habitats showed a lower seedling survival rate than did wet ones, mainly due to summer drought. Both the difference between Atlantic and Mediterranean categories, and the difference between habitats in Sierra Nevada reflect a serious limitation on recruitment of J. communis in Mediterranean mountains due to climatic stress imposed by summer drought. The Mediterranean populations provide a clear example of remnant dynamics, surviving for long periods due to great individual longevity which partially offsets losses to unfavourable environmental conditions. The low ability to recover after anthropic disturbances emphasizes the need for conservation of J. communis populations in southeastern Spain. (C) 1998 Elsevier Science Ltd. All rights reserved.