ÖRÜMCEK ORMANI (KÜRTÜN) VE ÇEVRESİNDE DENDROKRONOLOJİK ANALİZLER: İLK BULGULAR - DENDROCHRONOLOGICAL ANALYSIS OF ÖRÜMCEK FOREST (KÜRTÜN) AND ITS SURROUNDINGS: PRELIMINARY FINDINGS


Gürçay B., Köse N., Avcı M.

2. İstanbul Uluslararası Coğrafya Kongresi, 17-2 Haziran 20212nd İstanbul International Geography Congress, 17-20 June 2021, İstanbul, Turkey, 17 - 20 June 2021, pp.184-186

  • Publication Type: Conference Paper / Summary Text
  • City: İstanbul
  • Country: Turkey
  • Page Numbers: pp.184-186

Abstract

Anatolia is one of the most important areas of the world, which contains many different spatial differences as a result of its physical geography features and their interactions with each other.This differentiation also affected the distribution and structure of Anatolian forests. Forests are complex ecosystems in terms of their structures and they host many different organisms. There is an ecosystem specific to this area, especially in Black Sea Region forests, which are shaped
by the relations of climate and topography variables with each other. In this regard, many forests in the Eastern Black Sea Region have vital importance with their important and sensitive
ecosystems. Kürtün Örümcek Forests and its surroundings which were one of these forests were chosen as the research area. This area is located in the Eastern Black Sea part of the Black Sea Region and is within the borders of Gümüşhane province, Kürtün district. It should also be noted that the Kürtün Örümcek Forests, which are within the boundaries of the field, were declared as a "Nature Protection Area" in 1998 by the General Directorate of National Parks.
This declaration provided that these forests keep their own dynamics, away from human effects and thus, providing an opportunity to understand the structure of these forests.
In the study, it is aimed to determine the relationships between the radial growth of trees and climate and to create local chronologies by using the annual rings of the Örümcek forests and surrounding coniferous trees. Oriental spruce or Caucasian spruce (Picea orientalis), the Nordmann fir or Caucasian fir (Abies nordmanniana ssp. nordmanniana) and Scots pine  (Pinus sylvestris), which are the dominant tree species of the area, were sampled for the study. The field work was carried out in September 2020 and a total of 10 increment items were taken from 65 trees in 5 regions. These regions are coded as ORU for Örümcek Forests location, GAV for Gavraz Stream Basin, SAD for Şadi Highland location, CIK for Çıkrıkdüzü Highland
location and BAK for Bakacak Tepe location. Increment items were placed on paper carriers to
prevent them from being damaged, and some information such as area code and tree number
was written on them. Local information, coordinates, elevation, aspect and, if any, important information that will contribute to the study were recorded in the field book. In order to get
visual information, the area was photographed and recorded as video with the help of a drone.
The samples brought to the laboratory were placed on wooden carriers because they offered protection during processing and made measurement easier. In this way, after the transverse
surfaces were sanded, they were measured with a precision of 0.01 mm in the LINTAB-TSAP Measurement System, and the missing and false ring problems were eliminated. The time series for each annual ring was then standardized and then de-correlated. As a result, residual chronologies of each region were obtained. Correlation coefficients method was used to
determine the relations between regional chronologies and climate. Correlation coefficient values were made using the DENDROCLIM2002 program and the Treeclim package in
RStudio, which provides a statistically and temporally moving representation of the relationships between climate and tree growth. Long-year (1930-2019) average temperature and monthly total precipitation data for the area and its surroundings, for the area where the site is located, were obtained from the CRU TS 4.04 (land) data set for the area determined according to the field coordinates in the World Meteorological Organization (WMO).

According to results of the study;
1) Dendrochronological Findings;
a) 304 years for Oriental spruce / Nordmann fir samples at altitudes between 1400-1600 m in the ORU region,
b) 300 years for Scotch pine samples taken from altitudes of 1800 m and above in the GAV region,
c) 232 years for Oriental spruce samples taken from altitudes of 1800 m and above in the SAD region,
d) 219 years for Oriental spruce samples from 1700-1800 m altitudes in the CIK region,
e) 206 years for Scotch pine specimens from heights of 1800 m and above in the BAK region
2) Dendroclimatological Findings
When the correlation coefficient values between the region chronologies and climate data are examined:
(a) Tree ring-precipitation relationship: It has been observed that the monthly average precipitation values and the ring widths in all regions have a positive effect on the development
of the tree ring in May, which is above the average. In ORU, CIK and BAK regions, it has been observed that the January precipitation, which is above the average, has a negative effect
on tree ring development.
(b) Tree ring-temperature relationship: It has been observed that the values between February- March-April and July-August, which are above the average, between monthly average
temperature values and ring widths in all regions have a positive effect on tree ring development. The correlation coefficient measured between tree ring widths and monthly
average temperature values in the GAV region is not statistically significant.
In summary, the correlation coefficient values between the local chronologies and climate data showed that the late winter-early spring and summer period (July-August) temperatures above
the average and the May precipitation have positive effects on the tree ring development.
According to the findings, local chronologies are potential data source for climate reconstructions thanks to its length and climate sensitivity. The results of the research will
contribute to the understanding of the long-term trends in the relationships between tree ring records and climate elements, the responses of trees to these changes, and the effects of climate change on forests in the Eastern Black Sea Region.
Keywords: Climate change, dendrochronology, Kürtün Örümcek Forests, Kürtün, Anatolia

Ormanlar, karmaşık ekosistemlerdir ve bünyelerinde çok farklı organizmalara ev sahipliği yaparlar. Bu hususta Doğu Karadeniz Bölümünde pek çok orman önemli ve hassas ekosistemlere sahiptir. Bu ormanlar içerisinde yer alan Kürtün Örümcek Ormanları ve çevresi araştırma sahası olarak seçilmiştir. Bu alan Karadeniz Bölgesinin, Doğu Karadeniz Bölümünde yer alır ve Gümüşhane ili, Kürtün ilçesi sınırları içerisinde kalır. Bu çalışmada, Örümcek Ormanları ve çevresindeki koniferağaçların yıllık halkalarından yararlanarak yöre kronolojileri oluşturulması ve ağaçların radyal büyümesi ile iklim arasındaki ilişkilerin belirlenmesi amaçlanmıştır.Çalışmada, araştırma alanınınbaskın ağaç türleri olan Doğu ladini (Picea orientalis), Doğu Karadeniz göknarı (Abies nordmannianassp.nordmanniana) ve sarıçam (Pinus sylvestris) ağaçları örneklenmiştir. Arazi çalışması 2020 yılının Eylül ayında yapılmış ve 5 yörede 65 ağaçtan toplam 130artım kalemi alınmıştır.Örneklerin enine yüzeyleri mparalandıktan sonra, 0,01 mm hassasiyetle LINTAB-TSAP Ölçüm Sisteminde ölçülerek eksik ve yalancı halka problemleri giderilmiştir. Daha sonra her bir yıllık halka zaman serisi standardize edilmiş ve ardından otokorelasyondan arındırılmıştır. Sonuç olarak,her bir yöreye ait residual kronolojiler elde edilmiştir. Yöre kronolojileri ile iklim arasındaki ilişkilerin belirlenmesinde korelasyon katsayıları yöntemi kullanılmıştır. İklim verisi olarak 1930-2020 dönemi için Dünya Meteoroloji Organizasyonu (WMO)’ndan saha koordinatlarına göre elde edilenortalama sıcaklık ve aylık toplam yağış verileri kullanılmıştır.Çalışma sonuçlarına göre; (1) Elde edilen en uzun yöre kronolojisi 304 yıl ile Örümcek Ormanı (ORU) yöresinden doğu ladini türü için, en kısa yöre kronoloji ise 206 yıl ile Bakacak Tepe (BAK) yöresinden sarıçam türü için oluşturulmuştur (2) Oluşturulan yöre kronolojileri ile iklim verisi arasındaki korelasyon katsayı değerleri, ortalamanın üzerindeki kış dönemi sıcaklıkları ve mayıs yağışlarının ağaç halkası gelişimi üzerinde olumlu etkileri olduğunu göstermiştir. Bu çalışmada sunulan yöre kronolojileri uzunlukları ve iklime duyarlılıkları nedeniyle iklim rökonstrüksiyonları için potansiyel veri kaynağı niteliğindedir. Araştırma sonuçları, iklim değişikliğinin Doğu Karadeniz Bölümü’ndeki ormanlara etkilerinin anlaşılmasına katkı sağlayacaktır.


Anahtar Kelimeler: İklim değişikliği, dendrokronoloji, Örümcek Ormanları, Kürtün, Anadolu.