Burtis J C, Ostfeld R S, Yavitt J B, Fahey T J
Cornell University, Department of Natural Resources, Fernow Hall, Ithaca, NY 14853 (
Cary Institute of Ecosystem Studies, 2801 Sharon Turnpike, Millbrook, NY 12545 (
J Med Entomol. 2016 Jan;53(1):225-9. doi: 10.1093/jme/tjv151. Epub 2015 Oct 19.
We explored the relationship between the diversity and abundance of the soil arthropod predator community and the overwinter survival of engorged larval Ixodes scapularis Say under variable snow cover in a hardwood forest. We reduced the snow cover over 30 soil core field microcosms, simulating predicted changes in snow pack in the northeastern United States. An additional 29 microcosms were used as references with no snow pack manipulation. Each microcosm contained 15 engorged larval I. scapularis. We expected lower soil temperature without insulating snow cover to reduce tick survival. However, we observed that reduced snow cover had no effect, with 44.2 and 44.7% overwintering successfully in the reference and snow-removal plots, respectively. Increasing taxonomic family richness of arthropod predators and the total number of large (>1 mm) arthropod predators significantly reduced the overwinter survivorship of I. scapularis within the microcosms. Small (<1 mm) arthropod predator abundance had no effect. Our results suggest that forests with complex natural arthropod predator communities show reduced tick survival.
我们探究了硬木森林中，在不同积雪覆盖条件下，土壤节肢动物捕食者群落的多样性和丰度与饱血的肩突硬蜱幼虫越冬存活之间的关系。我们对30个土壤核心野外微观环境的积雪进行了减少处理，模拟美国东北部积雪的预测变化。另外29个微观环境作为对照，未对积雪进行处理。每个微观环境包含15只饱血的肩突硬蜱幼虫。我们预计没有隔热积雪覆盖的情况下土壤温度会降低，从而减少蜱的存活。然而，我们观察到积雪减少并无影响，对照区和除雪区分别有44.2%和44.7%的蜱成功越冬。节肢动物捕食者分类科丰富度的增加以及大型（>1毫米）节肢动物捕食者的总数显著降低了微观环境中肩突硬蜱的越冬存活率。小型（<1毫米）节肢动物捕食者的丰度则没有影响。我们的结果表明，具有复杂自然节肢动物捕食者群落的森林中蜱的存活率较低。
