Possibility of identification of negative extreme climatic events using Pinus sylvestris tree-rings in Transdanubia, Hungary

Abstract

Negative climatic extremes occur more frequently in the last decades. Since the Carpathian Basin is highly concerned in their impacts it is important to investigate prior events and estimate the response of the environment to them to get useful information for the future. In our work we selected a stand which is seriously affected by unfavorable summer conditions to examine what kind of fingerprint the negative extreme events have left. We investigated narrow rings and intra-annual density fluctuation to describe years with extreme events. Their stabilized frequency was tested against climatic and groundwater data, as well as against aridity index to determine climate-growth relationships using Pearson and Spearman's correlations. Our results show positive significant correspondence between summer precipitation and treering growth together with negative connection with summer temperature. The Spearman's correlation between stabilized frequency of intra-annual density fluctuations, narrow rings and climate data ended with significant relationship in summer. According to the comparison of intra-annual density fluctuation and narrow ring data with drought periods it can be said that narrow rings are better tool for the examination of negative extreme events in summer.

Differences in the Climate-Growth Relationship of Scots Pine: A Case Study from Poland and Hungary

“…It is interesting that we also found differences in the indicators related to winter and early spring temperatures (Table 1). Our findings agree with previous studies [5][6][7]41] that these factors have the most influence on tree-ring width formation of Scots pine. At the Polish site, the values of minimum temperature in the coldest month and mean temperature in the coldest quarter are lower than in Hungary (Table 1).…”

“…Research conducted on the Iberian Peninsula and in Mongolia show that rainfall deficiency in summer can be the most limiting factor for species establishment in southernmost localities, with low summer rainfall directly leading to high mortality of seedlings [34][35][36]. Water deficiency in the warmest quarter is also important as a limiting factor for radial growth of this species [7,8,37,38]. This might be the most important reason behind the absence of native populations of Scots pine in Hungary.…”

“…In Poland, wide rings are formed especially when higher temperatures are observed in February and March and when there is precipitation during the vegetation season [4]. In Hungary, precipitation from June to July and temperatures from February to March, are the dominant controls with summer temperatures playing the secondary role [5][6][7][8]. In northeastern Germany wide rings are formed during wet/warm February and wet/cool June [9].…”

Growth response of different tree species (oaks, beech and pine) from SE Europe to precipitation over time

“…Temperature or precipitation played little or no role in the growth of Scots pine at high elevation; the only factor affecting growth was drought , which is an indication of potential limitation posed by climate if climate changes tend towards decreasing precipitation. Our research is in accordance with the findings of the other authors who found that the growth of Scots pine in the studied region mainly depends on the amount of available precipitation (Misi & Náfrádi, 2016) or severity of drought (Misi & Ná-frádi, 2017) and less on temperature (Sidor & Popa, 2015). Some authors found an indirect connection between climate and growth of Scots pine -Poljanšek et al (2015) found a close connection between a hot and dry summer and the number of needles of the terminal bud, while Panayotov et al (2012) found a connection between drought and partial or complete absence of latewood if the summer in the year of ring formation was dry and warm.…”

Magyarországi erdeifenyő állományok komplex dendroklimatológiai elemzése az elmúlt 100 év klímaváltozásának tükrében

“…Az extrém események jelentős mértékben befolyásolják az adott évben keletkező évgyűrű jellemzőit, ezzel szignifikáns hatást gyakorolva az évgyűrűmintázatra. A szélsőség jellegétől függően kialakulhatnak világos évgyűrűk (Liang-Eckstein 2006), fagyott évgyűrűk (Hantemirov et al 2004;Kern-Popa 2008;Bräuning et al 2016), éven belüli sejtsűrűség ingadozások (de Luis et al 2011;De Micco et al 2013 Misi-Náfrádi 2016a), szokatlanul vékony évgyűrűk (Panayotov et al 2013;Misi-Náfrádi 2016a), de bizonyos esetekben lokálisan, vagy akár a törzs teljes keresztmetszetéből hiányzó évgyűrűk is. Ezen felsorolásból kiemelhető az éven belüli sejtsűrűség ingadozás, melyet korábban álévgyűrűként is aposztrofáltak, valamint a szokatlanul vékony évgyűrűk, ugyanis mindkét évgyűrűkarakter-módosulat jól azonosítható már makroszkóposan is, ezáltal marker jellegük kihangsúlyozódik, mely a keresztdatálás során fontos szempont lehet, továbbá az esetek többségében mindkettő markáns külső stresszhez köthető.…”