Unpalatable plants protect neighbors from grazing and increase plant community diversity
Unpalatable plants protect neighbors from grazing and increase plant community diversity
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DOI：
10.1890/04-0784
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发表时间：
2005-07-01
期刊：
影响因子：
4.8
通讯作者：
Khetsuriani, L
中科院分区：
文献类型：
--
作者：
Callaway, RM;Kikodze, D;Khetsuriani, L
美味的植物可以通过不好吃的邻居来保护它们不受食草动物的伤害。我们使用实验围栏，去除不好吃的物种，可口和不好吃的物种在亚高山草甸的格鲁吉亚的高加索山脉，研究两个不好吃的物种对植物群落的影响。我们发现，大蓟obalatum和藜芦，两个大的本地多年生草本植物，侵入后，沉重的，放牧，有很强的促进作用，通过其对家畜食草动物的间接影响的社区。这些不好吃的入侵者有不同的影响，当牲畜存在时，比牲畜被排除在外的社区组成。此外，删除蓟和藜芦草食动物被允许减少相关的社区的丰富度，但在牲畜围栏去除这些物种增加了社区的丰富度。移植的可口的物种（黄花和Phalpinum）生长较大的围合物内，并在围合物中蓟和Veratrunt没有影响他们的生长。而在围栏外，小蓟和藜芦对A. odoratum和P. alpinum。排除家畜会降低另一种不好吃的物种- pseudosudetica外封。相反，在围隔内，蓟和藜芦对L.假南美线虫我们的研究结果表明，蓟和藜芦，这是在某些方面不受欢迎的牧场杂草，也可能发挥重要作用，在高加索地区过度放牧植物群落的物种和功能多样性的维护。
Tasty plants can be protected from herbivores by unpalatable neighbors. We used experimental exclosures, removal of unpalatable species, and transplants of palatable and unpalatable species in subalpine meadows of the Caucasus Mountains of Georgia to study the effects of two unpalatable species on plant communities. We found that Cirsium obalatum and Veratrum lobelianum, two large native perennial herbs that invade after heavy,grazing, had strong facilitative effects on communities through their indirect effects on livestock herbivores. These unpalatable invaders had different effects on community composition when livestock were present than when livestock were excluded. Furthermore, removing Cirsium and Veratrum where herbivory was permitted decreased the richness of associated communities, but inside a livestock exclosure removal of these species increased community richness. Transplanted palatable species (Anthoxanthum odoratum and Phleum alpinum) grew larger inside the exclosure, and in the exclosure Cirsium and Veratrunt had no effect on their growth. However, outside of the exclosure, Cirsium and Veratrum had strong positive effects on the growth of A. odoratum and P. alpinum. Excluding livestock decreased the growth of Luzula pseudosudetica, another unpalatable species, and Cirsium and Veratrunt had no effect on L. pseudosudetica outside the exclosure. In contrast, inside exclosures Cirsium and Veratrum had competitive effects on L. pseudosudetica. Our results indicate that Cirsium and Veratrum, which are in some ways undesirable rangeland weeds, may also play an important role in maintaining species and functional diversity of overgrazed plant communities in the Caucasus.