Positive interactions among alpine plants increase with stress
Positive interactions among alpine plants increase with stress
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DOI：
10.1038/nature00812
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发表时间：
2002-06-20
期刊：
影响因子：
64.8
通讯作者：
Cook, BJ
中科院分区：
文献类型：
--
作者：
Callaway, RM;Brooker, RW;Cook, BJ
植物可以相互产生积极影响(1)。例如，某些物种积累养分、提供遮荫、改善干扰或保护其免受食草动物的侵害，可以提高邻近物种的性能。因此，植物物种的分布和丰度独立于其他物种的概念可能不足以作为理解物种共存和多样性的理论基础(2)。但还没有大规模的实验来检验植物群落中积极相互作用的普遍性及其相对于竞争的重要性。在这里，我们表明，当附近有其他植物时，高山植物物种的生物量、生长和繁殖会更高。在对 11 个不同山脉的 115 个物种的亚高山和高山植物群落进行的一项实验中，我们发现竞争通常（但并非完全）在较低海拔地区的相互作用中占主导地位，因为那里的物理压力较小。相比之下，在非生物胁迫严重的高海拔地区，植物之间的相互作用主要是积极的。此外，在所有高位点和低位点，在初夏气温较低的地点，积极的相互作用更为重要，但在温暖的地点，竞争盛行。
Plants can have positive effects on each other(1). For example, the accumulation of nutrients, provision of shade, amelioration of disturbance, or protection from herbivores by some species can enhance the performance of neighbouring species. Thus the notion that the distributions and abundances of plant species are independent of other species may be inadequate as a theoretical underpinning for understanding species coexistence and diversity(2). But there have been no large-scale experiments designed to examine the generality of positive interactions in plant communities and their importance relative to competition. Here we show that the biomass, growth and reproduction of alpine plant species are higher when other plants are nearby. In an experiment conducted in subalpine and alpine plant communities with 115 species in 11 different mountain ranges, we find that competition generally, but not exclusively, dominates interactions at lower elevations where conditions are less physically stressful. In contrast, at high elevations where abiotic stress is high the interactions among plants are predominantly positive. Furthermore, across all high and low sites positive interactions are more important at sites with low temperatures in the early summer, but competition prevails at warmer sites.