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Effects of climate warming on vegetative phenology of the common beech Fagus sylvatica in a submontane forest of the Western Carpathians: two-decade analysis

100%

Schieber B., Kubov M., Janik R.

Polish Journal of Ecology

2017

tom 65

nr 3

The paper examines the results of phenological research on common beech (Fagus sylvatica L.) during a period of 21 years (1995–2015) in the submontane beech forest of central Slovakia (Inner Western Carpathians). We focused on bud-burst, leaf unfolding and leaf colouring. Temporal analysis indicated that the mean monthly air temperature increased, especially from April to August. An extraordinary increase of air temperature in March and April, mostly in the last decade, was detected. The precipitation from May to August varied considerably, but in the range of the long-term mean value. During the study period, the mean/earliest/ latest onset of the bud-burst of common beech was observed on the 110th /101st/120th day of the year (DOY), respectively. As for leaf unfolding 10% and 50% (LU 10 and LU 50), we found the mean/earliest/latest onset on the 114th/103rd/122nd DOY and on the 118th/108th/124th DOY, respectively. The mean/earliest/latest onset of leaf colouring 10% (LC 10) and 50% (LC 50) started on the 272nd/262nd/288th DOY and on 286th/276th/298th, respectively. A medium degree of negative correlation (r = -0.68, P < 0.05) was found between air temperature and spring plant development (LU 50). In contrast, for both the cumulative temperature and precipitation, we found very low correlation with autumnal leaf phenology (r ≤ 0.3, P > 0.05). The vegetation period of the examined tree species lasted for 168 days on average (min/max were 155/183 days). Trend analysis revealed an earlier onset of spring phenophases by 7 days/2 decades. Conversely, a delay of autumnal phenophases by 9 days was recorded, so the vegetation period of beech extended by more than two weeks during the study period.

Effects of post-cutting changes in site conditions on the morphology and phenology of naturally regenerated beech seedlings [Fagus sylvatica L.]

100%

Barna M., Schieber B., Cicak A.

Polish Journal of Ecology

2009

tom 57

nr 3

461-472

We studied the response in growth and phenology of naturally regenerated beech seedlings to changed ecological conditions over 14 and 19-years after cutting with different intensity. Five different types of stand densities were modelled: plot C – control plot – no cut, L – low intensity cut, M – medium intensity cut, H – high intensity cut and CC – clear cut, with 1, 8, 22, 53 and 100% of relative irradiation, and 66, 68, 78, 92 and 100% of through fall, respectively. We were focussing on tree height growth and leaf area. Our phenological observations were aimed at onset and course of two spring vegetative phenophases: bud-burst and leaf unfolding. Already in two-year-old beech seedlings we found significant differences in height growth; the differences in mean leaf area, however, were observed later. From the viewpoint of phenotypic plasticity, the height growth in beech seedlings represented more sensitive response to the environment than the leaf area. According to leaf area size and height growth in the beech seedlings on control plot, the stress conditions were indicated, primarily from the lacking light. With stand opening, the development of recruitment was getting better, and beginning with plot M the increase of seedlings height and leaf area became continuously related to the amount of radiation. The results of phenological observations showed that the spring phenophases in the seedlings start first on control plot. The start of spring phenophases on the clearcut was always observed the latest, even in comparison with the parent stand. Correlation analysis confirmed a significant correlation (P <0.05, r = -0.61) between the mean air temperature in March and April and start of the phenophase leafing in the individual years. Analysis of long-term research showed that the trend of leafing’s onset observed in course of 18 years was significant (P <0.05), manifested a shift towards earlier dates.

Ograniczanie wyników

2 Polish Journal of Ecology

2 Schieber B.

1 Barna M.

1 Cicak A.

1 Janik R.

1 Kubov M.

1 2017

1 2009

Wyniki wyszukiwania

Effects of climate warming on vegetative phenology of the common beech Fagus sylvatica in a submontane forest of the Western Carpathians: two-decade analysis

Effects of post-cutting changes in site conditions on the morphology and phenology of naturally regenerated beech seedlings [Fagus sylvatica L.]