National Institute for Research and Development in Forestry "Marin Drăcea", Calea Bucovinei, 73 bis, 725100, Câmpulung Moldovenesc, Romania.
University of Ljubljana, Biotechnical Faculty, Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia.
Sci Total Environ. 2019 Dec 1;694:133730. doi: 10.1016/j.scitotenv.2019.133730. Epub 2019 Aug 2.
Three gridded datasets containing interpolated daily and monthly precipitation and temperature values over the past five decades were tested against four tree-ring chronologies of oak (Quercus robur and Q. petraea). The objective of this research was to investigate the climate-growth relationship and whether the Pearson's product-moment correlation coefficients differ significantly if mean monthly precipitation and temperature data from the different climate databases, CRU, E-OBS and ROCADA are used. To this end, we selected two representative oak ecosystems in the South Carpathians, Romania, and analysed earlywood, latewood and tree-ring widths. Climate time series trends for the South Carpathians coldest, warmest days and wettest days were assessed with datasets from E-OBS and ROCADA, which differed in the density of their meteorological station network and their interpolation methods. The observed climatic parameters showed changes towards wetter conditions after the mid-1980s. For 1961-2013, E-OBS underestimated the mean daily temperature and daily precipitation compared with ROCADA. The results showed that higher extreme temperatures from January-March affected earlywood growth. In the investigated study region, latewood formation seemed to be affected by water availability mainly in May. Periods of drought associated with higher temperatures have limiting effects on tree growth, but these events are captured in different ways by each climate database analysed. Similarly, the results showed the discrepancy among datasets for earlywood and climate relationships. The results emphasize the importance of proper selection of climate data for assessing climate-tree growth relationships. For future dendroclimatological and dendroecological studies of oak in Romania, we recommend the ROCADA database, while E-OBS is recommended if an up-to-date climate dataset is needed.
三个网格化数据集包含过去五十年插值的日和月降水和温度值，与四个橡树（Quercus robur 和 Q. petraea）的树木年轮年表进行了测试。本研究的目的是调查气候-生长关系，以及如果使用不同气候数据库（CRU、E-OBS 和 ROCADA）的平均月降水和温度数据，皮尔逊乘积矩相关系数是否有显著差异。为此，我们选择了罗马尼亚南喀尔巴阡山脉的两个具有代表性的橡树生态系统，并分析了早材、晚材和树木年轮宽度。使用 E-OBS 和 ROCADA 的数据集评估了南喀尔巴阡山脉最冷、最热和最潮湿天数的气候时间序列趋势，这两个数据集在气象站网络密度和插值方法上有所不同。观察到的气候参数显示，自 20 世纪 80 年代中期以来，条件向湿润方向变化。对于 1961-2013 年，E-OBS 低估了平均日温度和日降水，与 ROCADA 相比。结果表明，1 月至 3 月较高的极端温度影响早材生长。在所研究的研究区域中，晚材形成似乎主要受 5 月水分供应的影响。与较高温度相关的干旱期对树木生长有限制作用，但这些事件被分析的每个气候数据库以不同的方式捕捉。同样，结果表明数据集之间在早材和气候关系上存在差异。结果强调了为评估气候-树木生长关系选择适当气候数据的重要性。对于罗马尼亚未来的橡树树轮气候学和树木生态学研究，我们建议使用 ROCADA 数据库，而如果需要最新的气候数据集，则建议使用 E-OBS。
