Arthropod communities in the Second College Grant, NH

Arthropods are active during the winter in temperate regions. Many
use the seasonal snowpack as a buffer against harsh ambient
conditions and remain active in a refugium known as the subnivium.
While the use of the subnivium by insects and other arthropods is
well-established, far less is known about winter community
composition, abundance, biomass, and diversity and how these
characteristics compare with the community in the summer.
Understanding subnivean communities is especially important given
observed and anticipated changes in snowpack depth and duration with
changing climate. We studied winter and summer insects and other
arthropods using pitfall trapping in northern New Hampshire, where
snowpack is still relatively intact. We found that compositions of
the subnivium and summer arthropod communities differed. The
subnivium arthropod community featured moderate levels of richness
and other measures of diversity that tended to be lower than in the
summer community. More striking, the subnivium community was much
lower in overall abundance and biomass than the summer community.
Interestingly, some groups and species of arthropods were dominant
in the subnivium but either rare or absent in summer collections.
These putative “subnivium specialists” included one spider (order:
Araneae), Cicurina brevis (Emerton,
1890 ) , and three rove beetles (order:
Coleoptera, family: Staphylinidae ) Arpedium cribratum Fauvel, 1878, Lesteva pallipes LeConte, 1863, and Porrhodites inflatus (Hatch, 1957). This study
provides a detailed account of the subnivium arthropod community,
presents novel concepts, and establishes baseline information on
arthropod communities in the North American northeastern temperate
forest.

温带地区的节肢动物在冬季仍保持活动。许多类群会借助季节性积雪层作为缓冲，抵御恶劣的外界环境，并在被称为雪下层（subnivium）的避难生境中维持活动状态。
尽管昆虫及其他节肢动物对雪下层的利用已得到充分证实，但学界对冬季群落的组成、个体数量、生物量与多样性，以及这些特征与夏季群落的差异却知之甚少。
鉴于气候变化背景下观测到及预计发生的积雪层深度与持续时间变化，了解雪下层群落的特征尤为重要。
本研究在积雪仍相对完整的新罕布什尔州北部，采用陷阱诱捕法对冬季与夏季的昆虫及其他节肢动物展开调查。
研究结果显示，雪下层与夏季节肢动物群落的组成存在显著差异：雪下层节肢动物群落的物种丰富度及其他多样性指标均处于中等水平，且整体低于夏季群落；更为显著的是，雪下层群落的总个体数量与生物量远低于夏季群落。
值得注意的是，部分节肢动物类群与物种在雪下层占据优势地位，但在夏季采集样本中却极为罕见甚至完全缺失。
这些被推断为“雪下层特化种”的类群包括1种蜘蛛（蜘蛛目Araneae）——短隙蛛（Cicurina brevis，Emerton, 1890），以及3种隐翅虫（鞘翅目Coleoptera，隐翅虫科Staphylinidae）：Arpedium cribratum Fauvel, 1878、Lesteva pallipes LeConte, 1863与Porrhodites inflatus (Hatch, 1957)。
本研究详细记述了北美东北部温带森林中的雪下层节肢动物群落，提出了全新的研究理念，并为该区域的节肢动物群落建立了基准参考数据。