Reindeer use of low Arctic tundra correlates with landscape structure
Reindeer use of low Arctic tundra correlates with landscape structure
复制标题
驯鹿对低北极苔原的利用与景观结构相关
DOI：
10.1088/1748-9326/abbf15
复制
发表时间：
2020
影响因子：
6.7
通讯作者：
B. Forbes
中科院分区：
文献类型：
--
作者：
A. Skarin;Mariana Verdonen;T. Kumpula;M. Macias‐Fauria;Moudud Alam;Jeffrey T. Kerby;B. Forbes
北极地区的快速气候变化与木质分类群（灌木化）的扩张以及随着冻土带变绿而增加的生物量有关。驯鹿和北美驯鹿（Rangifer tarandus）被认为能够通过放牧和践踏来抑制植被绿化。量化驯鹿对不同土地覆盖类型的利用可以帮助我们了解它们对落叶灌木生长和补充的影响，其中许多落叶灌木在有利的栖息地（如永久冻土区自然剥落的滑坡）中充当饲料（例如柳属）。了解驯鹿对植被压力的空间分布，对于预测持续气候变化下苔原牧场的绿化、反照率、积雪捕获、活动层发育和整体恢复力的未来模式具有重要意义。在这里，我们量化了西伯利亚西部亚马尔低北极冻土带驯鹿栖息地的使用，根据颗粒群计数估计，以及活跃层厚度（ALT）与驯鹿使用的关系。研究结果表明，驯鹿对6 - 7月时间综合归一化植被指数较高的地形、更陡峭的斜坡、山脊、上坡和山谷以及低直立灌木苔原的利用程度较高。与驯鹿较少使用的网站相比，这些网站的ALT似乎也较浅，尽管我们没有发现ALT和驯鹿使用之间的任何直接关系。对高柳树生境的低利用表明，驯鹿不太可能抑制已经很高的直立木本类群的生长，而它们在灌木已经很低的地方施加最大的压力，例如山脊顶。驯鹿抑制滑坡区（即洼地）木质分类群的再生和扩张的能力似乎有限，因为这些类型很少被使用。我们的研究结果表明，驯鹿对景观的利用及其对景观的影响与景观结构相关。未来的研究需要评估驯鹿作为能够调节气候变化影响的生态系统工程师的作用和效率。
Rapid climate change in Arctic regions is linked to the expansion of woody taxa (shrubification), and an increase in biomass as tundra becomes greener. Reindeer and caribou (Rangifer tarandus) are considered able to suppress vegetative greening through grazing and trampling. Quantifying reindeer use of different land cover types can help us understand their impact on the growth and recruitment of deciduous shrubs, many of which serve as fodder (e.g. Salix spp.), in favourable habitats, such as naturally denuded landslides in permafrost areas. Understanding the spatial distribution of reindeer pressure on vegetation is important to project future patterns of greening, albedo, snow capture, active layer development, and the overall resilience of tundra rangelands under ongoing climate change. Here we quantify reindeer habitat use within the low Arctic tundra zone of Yamal, West Siberia estimated from pellet-group counts, and also how active layer thickness (ALT) relates to reindeer use. Our results confirm intensive use by reindeer of terrain with high June-July time integrated normalised difference vegetation index, steeper slopes, ridges, upper slopes and valleys, and a preference for low erect shrub tundra. These sites also seem to have a shallower ALT compared to sites less used by reindeer, although we did not find any direct relationship between ALT and reindeer use. Low use of tall Salix habitats indicated that reindeer are unlikely to suppress the growth of already tall-erect woody taxa, while they exert maximum pressure in areas where shrubs are already low in stature, e.g. ridgetops. Reindeer ability to suppress the regrowth and expansion of woody taxa in landslide areas (i.e. concavities) seems limited, as these types were less used. Our results suggest that reindeer use of the landscape and hence their effects on the landscape correlates with the landscape structure. Future research is needed to evaluate the role and efficiency of reindeer as ecosystem engineers capable of mediating the effects of climate change.
影响因子：
1.9
作者：
COUGHENOUR, MB
通讯作者：
COUGHENOUR, MB