Nematode Distribution and Function in Antarctic Dry Valley Ecosystems

关于线虫在南极无雪的干燥山谷中的分布和功能重要性，人们知之甚少。人们将干旱的山谷与世界上其他沙漠地区进行了比较。试图在紧张的沙漠生态系统中发挥作用的生物需要适应低水分可获得性和极端温度。该项目将检查和比较南极干旱山谷线虫群落的结构，并将其与研究得更好的沙漠生态系统的线虫群落结构进行比较。在夏末高峰期，将确定三个干旱河谷的线虫群落的分布和营养结构。线虫的分布、丰度和物种组成将与土壤的物理和化学性质有关，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，以确定线虫的数量是能量有限的，还是受到影响生存的非生物因素的限制。线虫对低土壤水分(脱水生物作用)和低温(隐生物作用)的适应性将在受控的实验室条件下进行研究。在莱特谷，将通过沿山谷轴线诱捕风传播线虫的方法来研究风传播线虫。

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 dispersed nematodes will be studied in Wright Valley by trapping wind dispersed nematodes along the axis of the valley.