Constraints to Ecosystem Development in High Arctic Polar Deserts

9300045幸福研究概述是1991年在加拿大德文岛贫瘠的高地高原上发起的一项研究的继续。本研究侧重于土壤发育、隐花结皮和维管植物在极地沙漠形成过程中的相互作用。将继续对结皮和非结皮场地的宏观景观特征进行研究。这项研究将扩大到包括石网和石条的中尺度特征，以及这些特征在土壤风化过程中所起的作用，隐形结壳的建立和固氮，以及结皮向土壤和维管植物的氮素转移。由于极地荒漠地区维管植物的作用有限，将研究根系对寒冷、贫瘠、霜冻扰动土壤的生理和生物力学适应，以及幼苗和成体碳积累和水分流失的作用。年复一年的巨大变异性为这个高度紧张的系统可能如何应对长期气候变化提供了线索。更好地了解广泛但鲜为人知的极地沙漠系统对气候变化的反应，将大大有助于实现与全球变化对北极极地环境的影响有关的方案目标。***

9300045 Bliss Research outlined here is a continuation of a study initiated in 1991 on the barren, upland plateau on Devon Island, Canada. This research focuses upon the interactive roles of soil development, and cryptogamic crust and vascular plant establishment and function in the formation of polar deserts. Research on the macroscale landscape features of crusted and non-crusted sites will continue. This study will be expanded to include the mesoscale features of stone nets and stripes and the role these features play in soil weathering processes, the establishment and nitrogen fixation of cryptogamic crusts, and the transfer of nitrogen from crusts to soils and vascular plants. The the physiological and biomechanical adaptations of root systems to cold, nutrient-poor, frosty disturbed soils, and the role of carbon accumulation and water rleations of seedlings and adults will be studied as these aspects relate to the limited role of vascular plants within vast areas of polar desert. The large year to year variability provides clues on how this highly stressful system may respond to longer term climate change. Better understanding the response to climate change of extensive, but little understood polar desert systems will contribute significantly to program goals related to the effect of global changes in the arctic polar environment. ***