Collaborative Research: Nematode Distribution and Function in Antarctic Dry Valley Ecosystems

人们对线虫在南极洲无雪干谷的分布和功能重要性知之甚少。干谷已被拿来与世界上其他沙漠地区作比较。适应低湿度和极端温度是生物体试图在压力大的沙漠生态系统中发挥作用的必要条件。这个项目将检查并比较南极洲干谷和研究得更好的沙漠生态系统的线虫群落结构。在南方夏季的高峰期，将确定三个干谷的线虫群落分布和营养结构。线虫的分布、丰度和种类组成与土壤的理化性质有关，包括有机碳、氮、盐度、pH、微生物数量和生物量。将用糖增加土壤的能量供应，以确定线虫数量是否受到能量限制或受到影响生存的非生物因素的限制。线虫对低土壤湿度（缺水）和低温（隐生）的适应将在受控的实验室条件下进行研究。通过在莱特山谷长轴上捕获风传播的线虫，研究了莱特山谷线虫的风传播。

Little is known about the distribution and functional importance of nematodes in the snow-free dry valleys of Antarctica. The dry valleys have been compared with other desert regions of the world. Adaptations to low moisture availability and extremes of temperature are required of organisms attempting to function in stressful desert ecosystems. This project will examine and compare the structure of nematode communities in the dry valleys of Antarctica with those of better studied desert ecosystems. The distribution and trophic structure of nematode communities will be determined for three dry valleys at the peak of the austral summer. Nematode distribution, abundance, and species composition will be related to soil physical and chemical properties including organic C, nitrogen, salinity, pH, and microbial number and biomass. The energy supply of soil will be augmented with sugar to determine if nematode numbers are energy limited or are limited by abiotic factors influencing survival. Nematode adaptations to low soil moisture (anhydrobiosis) and to low temperature (cryptobiosis) will be studied under controlled laboratory conditions. Wind dispersal of nematodes will be studied in Wright Valley by trapping wind dispersed nematodes along the long axis of the valley.