文章基本信息

标题：Climate Warming Postpones Senescence in High Arctic Tundra
其他标题：Climate Warming Postpones Senescence in High Arctic Tundra
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作者：Fleur L. Marchand ; Ivan Nijs ; Mark Heuer 等
期刊名称：Arctic, Antarctic, and Alpine Research
印刷版ISSN：1523-0430
电子版ISSN：1938-4246
出版年度：2004
卷号：36
期号：4
页码：390-394
DOI：10.1657/1523-0430(2004)036[0390:CWPSIH]2.0.CO%3B2
摘要：Lengthening of the growing season at high latitudes, observed by satellites with the Normalized Difference Vegetation Index (NDVI), has been ascribed to climate warming. To test this assumption, and to verify whether changes in vegetation greenness are quantitative or qualitative, we experimentally warmed patches of High Arctic tundra with infrared heating in Northeast Greenland. By analyzing digital images of the vegetation, changes in cover were distinguished from changes in senescence. During the season, experimental warming significantly increased green cover, for example, at the time of peak cover, the total green cover was enhanced from 59.1 to 67.3%. The dominant wavelength (hue) reflected by our tundra plots shifted from yellow-green to yellow. Experimental warming with 2.5°C delayed this hue-shift by 15 d. The results demonstrate that higher summer temperatures do not only promote plant growth at these latitudes but also retard and/or postpone the senescence process, contrary to indications from previous research that late-season phenology in the High Arctic is governed by photoperiod.