George Jan-Peter, Schueler Silvio, Karanitsch-Ackerl Sandra, Mayer Konrad, Klumpp Raphael T, Grabner Michael
Federal Research and Training Centre for Forests, Natural Hazards and Landscape (BFW), Department of Forest Genetics, Seckendorff-Gudent-Weg 8, 1131 Vienna, Austria.
University of Natural Resources and Life Sciences (BOKU), Institute of Wood Science and Technology, Konrad-Lorenz-Straβe 24, 3430 Tulln an der Donau, Austria.
Agric For Meteorol. 2015 Dec 15;214-215:430-443. doi: 10.1016/j.agrformet.2015.08.268.
Understanding drought sensitivity of tree species and its intra-specific variation is required to estimate the effects of climate change on forest productivity, carbon sequestration and tree mortality as well as to develop adaptive forest management measures. Here, we studied the variation of drought reaction of six European species and ten provenances of planted in the drought prone eastern Austria. Tree-ring and X-ray densitometry data were used to generate early- and latewood measures for ring width and wood density. Moreover, the drought reaction of species and provenances within six distinct drought events between 1970 and 2011, as identified by the standardized precipitation index, was determined by four drought response measures. The mean reaction of species and provenances to drought events was strongly affected by the seasonal occurrence of the drought: a short, strong drought at the beginning of the growing season resulted in growth reductions up to 50%, while droughts at the end of the growing season did not affect annual increment. Wood properties and drought response measures showed significant variation among species as well as among provenances. Whereas provenances explained significant parts in the variation of ring width measures, the species explained significant parts in the variation of wood density parameters. A consistent pattern in drought response across the six drought events was observed only at the inter-specific level, where showed the highest resistance and showed the best recovery after drought. In contrast, differences in drought reaction among provenances were only found for the milder drought events in 1986, 1990, 1993 and 2000 and the ranking of provenances varied at each drought event. This indicates that genetic variation in drought response within is more limited than among species. Low correlations between wood density parameters and drought response measures suggest that wood density is a poor predictor of drought sensitivity in .
为了评估气候变化对森林生产力、碳固存和树木死亡率的影响，以及制定适应性森林管理措施，需要了解树种的干旱敏感性及其种内变异。在此，我们研究了种植在奥地利东部干旱多发地区的6种欧洲树种和10个种源的干旱反应变异。利用年轮和X射线密度测定数据生成早材和晚材的年轮宽度和木材密度测量值。此外，根据标准化降水指数确定的1970年至2011年间6次不同干旱事件中，树种和种源的干旱反应通过4种干旱响应指标来确定。树种和种源对干旱事件的平均反应受干旱季节发生情况的强烈影响：生长季节开始时短暂而强烈的干旱导致生长减少高达50%，而生长季节结束时的干旱不影响年生长量。木材特性和干旱响应指标在树种间以及种源间均表现出显著差异。种源在年轮宽度测量值的变异中解释了显著部分，而树种在木材密度参数的变异中解释了显著部分。仅在种间水平观察到了6次干旱事件中干旱响应的一致模式，其中[树种名称1]表现出最高的抗性，[树种名称2]在干旱后表现出最佳的恢复能力。相比之下，仅在1986年、1990年、1993年和2000年较温和的干旱事件中发现种源间干旱反应存在差异，且每次干旱事件中种源的排名都有所不同。这表明[树种名称]种内干旱响应的遗传变异比种间变异更有限。木材密度参数与干旱响应指标之间的低相关性表明，木材密度不是[树种名称]干旱敏感性的良好预测指标。
