Short‐term effects of experimental goose grazing and warming differ in three low‐Arctic coastal wetland plant communities
Short‐term effects of experimental goose grazing and warming differ in three low‐Arctic coastal wetland plant communities
复制标题
实验性鹅放牧和变暖的短期影响对三个低纬度北极沿海湿地植物群落的影响不同
DOI：
10.1111/jvs.13139
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发表时间：
2022
影响因子：
2.8
通讯作者：
Beard, Karen H.
中科院分区：
文献类型：
--
作者：
Choi, Ryan T.;Petit Bon, Matteo;Leffler, A. Joshua;Kelsey, Katharine C.;Welker, Jeffrey M.;Beard, Karen H.
了解苔原湿地植物群落对食草动物和变暖的敏感性和程度是紧迫的，因为这些生态系统越来越受到放牧压力和温度升高的威胁。在这里，我们问在何种程度上不同的低北极沿海湿地植物群落的短期鹅放牧和变暖的影响，以及这些社区是否在他们的respons. LocationYukon Kuskokwim三角洲，Alaska.MethodsWe进行了一项实验，我们模拟鹅放牧通过修剪植被和夏季变暖通过使用开放式顶室在三个植物群落沿着6公里的沿海-内陆梯度。我们评估了植物群落组成的变化，经过两年的treatment. ResultsGrafing有更强的影响比变暖的植物功能群和物种组成。总体而言，放牧减少了丰富的草和莎草，并增加了丰富的杂类草，而变暖只造成减少杂类草丰富。然而，植物群落和功能群，无论是在社区内和跨社区，在他们的治疗反应差异很大。在另外两个沿海群落中，放牧减少了草的丰度（-25%），增加了杂类草的丰度（+44%），只有在最内陆的群落中减少了莎草的丰度（-22%）。变暖只减少了杂类草丰度（-18%）在最沿海的社区，这总体上是最敏感的treatments.ConclusionsWe表明，短期鹅放牧占主导地位的短期夏季变暖在三个不同的低北极沿海湿地植物群落的组成变化。然而，不同社区的反应各不相同，相同的功能群体在不同社区的反应也可能不同，这突出表明必须调查生物和非生物驱动因素在不同背景下的影响。通过表明苔原湿地植物群落对鹅放牧的直接敏感性不同，尽管在较小程度上，变暖，我们的研究结果对这些快速变化的高纬度生态系统的功能有影响。
QuestionUnderstanding the sensitivity and magnitude of plant community responses in tundra wetlands to herbivory and warming is pressing as these ecosystems are increasingly threatened by changes in grazing pressure and higher temperatures. Here, we ask to what extent different low‐Arctic coastal wetland plant communities are affected by short‐term goose grazing and warming, and whether these communities differ in their responses.LocationYukon–Kuskokwim Delta, Alaska.MethodsWe conducted an experiment where we simulated goose grazing by clipping the vegetation and summer warming by using open‐top chambers in three plant communities along a 6‐km coastal–inland gradient. We assessed plant community compositional changes following two years of treatments.ResultsGrazing had stronger effects than warming on both plant functional group and species composition. Overall, grazing decreased the abundance of grasses and sedges and increased the abundance of forbs, whereas warming only caused a decrease in forb abundance. However, plant communities and functional groups, both within and across communities, varied widely in their responses to treatments. Grazing decreased grass abundance (−25%) and increased forb abundance (+44%) in the two more coastal communities, and reduced sedge abundance (−22%) only in the most inland community. Warming only decreased forb abundance (−18%) in the most coastal community, which overall was the most responsive to treatments.ConclusionsWe show that short‐term goose grazing predominates over short‐term summer warming in eliciting compositional changes in three different low‐Arctic coastal wetland plant communities. Yet, responses varied among communities and the same functional groups could respond differently across them, highlighting the importance of investigating the effects of biotic and abiotic drivers in different contexts. By showing that tundra wetland plant communities can differ in their immediate sensitivity to goose grazing and, though to a lesser extent, warming, our findings have implications for the functioning of these rapidly changing high‐latitude ecosystems.