SCIENTIFIC AND TECHNICAL REPORT
on
the implementation of the project entitled
Radiocarbon dendrochronology, isotope dendroclimatology and conservation of monumental angiosperm
trees of the world
(Acronym RADACLIR)
Code
PN-III-P4-ID-PCE-2020-2567
Contract
No. PCE 145/2021
________________________________
for the period January - December
2021
SUMMARY OF
THE UNIQUE PHASE I (2021)
The project consists of 3 recurring
phases with identical designation, each with 4 identical objectives and similar
actions (action types). The differentiation is possible by the 1, 2 or 3 index, and I, II or III, respectively, which correspond to
the three different years of the project period and also to the different
investigated areas and angiosperm species. Accordingly, the phase for 2021 is
called Phase 1 – The conservation and protection of monumental trees and their
radiocarbon dating, and stable isotope analysis, respectively. The specific
objectives of Phase 1 concern the radiocarbon dating of baobabs (objective
1.1), the climate study based on wood samples collected from baobabs and
investigated by stable isotope analysis (objective 1.2), the measuring and
dating of angiosperm trees in Romania and Europe (objective 1.3) and the
dissemination of results (objective 1.4).
The
scientific activities of the research project performed during the
January-December 2021 implementation period pursued the fulfillment of the
objectives mentioned in the unique phase of the Project Implementation Plan for
2021.
Unique
phase 1 (2021): Conservation and protection of superlative trees and the AMS
radiocarbon investigation and stable isotope analysis of such trees (I).
Objective 1.1. Dating of baobabs (I).
Action 1.1.1. Sample collection from 35 baobabs.
Objective
1.2. Climate study (I).
Action 1.2.1. Sample
collection from 35 baobabs.
A
number of 45 representative African baobabs (Adansonia digitata) from Senegal and Tanzania were measured and
investigated. Samples for radiocarbon dating were collected from 36 specimens
(compared to 35 envisaged) and from 3 baobabs for stable isotope analysis,
respectively (compared to 3 envisaged).
An important
visit to Senegal took place in September-October 2021, with
special focus on the Dakar-M’bour-Fissel-Samba Dia area. With its 5-10 million
specimens, Senegal is the country with the highest number of African baobabs in
the northern hemisphere. Moreover, Senegal hosts the largest and oldest
superlative baobabs of the northern hemisphere.
In this respect,
we mention the baobab located close to the Sinthiou-Keita settlement, in the
proximity of Nianing town in the Thiès region. This baobab has the biggest wood
volume V = 300 m3 in the
northern hemisphere. It has a cluster structure composed of 3 common stems and
2 false stems (Fig. 1). The measurements are: height h = 22.5 m, circumference
(at 1.30 m above ground level) cbh = 27.10 m. The baobab is around 750 years
old.
Fig.
1. The Sinthiou-Keita baobab has the biggest wood volume (300 m3) in
the northern hemisphere.
Our research team investigated the sacred baobab of
Nianing, also in the Thiès region, which is a good candidate for the title of
Senegal’s oldest tree. Its closed ring-shaped structure is formed by 11 main
stems around a false cavity; 3 younger stems and a false stem are located
outside the ring(s) (Fig. 2). Its measurements are: h = 18.7 m, cbh = 24.70 m
and V = 180 m3.
Fig.
2. The Nianing baobab consists of 15 fused stems.
The
baobab with the largest circumference in the northern hemisphere remains the
baobab of Warang, Senegal. This remarkable tree has
18 stems. Its circumference now reaches cbh = 28.90
m. In 2019, we reported that the baobab, which was previously located on vacant
land, was enclosed in a yard of a newly built house. We expressed our concern
for the damage to the roots during the construction process and building of the
fence (Fig. 3). Currently, discussions with the French owner revealed that she
will protect the baobab as much as possible, paying it a special attention.
Fig. 3. The large baobab of Warang is now enclosed
between the fence walls of a backyard and has become a sort of “household
baobab”.
In August 2021, our research team travelled to
Tanzania, focusing on the baobabs of Unguja island (Zanzibar). Unguja island has a total area of 1666 km2
and a maximum length of 83 km, hosting a number of 50.000 – 100.000 African
baobabs. The majority are aggregated in the southern and northern regions and
partly in the central region, usually in the coastal areas.
The largest
baobab of Tanzania was located in Kizimkazi Dimbani in Zanzibar and had a wood
volume of 300 m3. This specimen was severely damaged during a heavy
storm, which led to its demise in April 2018. Some wood samples were collected
from the remains of its trunk and branches.
Close to Kizimkazi, in Makunduchi, a grove of large
baobabs can be found. The largest, which we called Makunduchi-1, exhibits a
cluster structure and consists of 8 common and 7 false stems (Fig. 4). The
measurements are: h = 19.5 m, cbh = 20.05 m, V = 180 m3. The baobab
has particular spherical-shaped pods of large sizes.
In the central-western region of Unguja, south of
Stone Town lies the Fumba Beach Lodge resort, right on the shores of the Indian
Ocean. The resort hosts several African baobabs and the largest, which we
called Fumba-1, grows among an unusual ancillary building area that reaches its
crown. The baobab has 4 common and one false stems that are fused together
forming a cluster structure (Fig. 5). Its measurements are: h = 14.3 m, cbh = 21.45 m, V = 140 m3.
Fig.
4. The Makunduchi-1 baobab has 15 fused stems.
Actions
1.1.2. Pretreatment (80 segments), 1.1.3. AMS radiocarbon dating (80 segments)
and 1.1.4. Calibration (80 segments).
85 wood segments
were pretreated by the acid-base-acid or α-cellulose pretreatment method,
then AMS (accelerator mass spectrometer) radiocarbon dated and subsequently calibrated
(compared to 80 envisaged).
The radiocarbon dating by AMS was performed at the iThemba Laboratory for Accelerator Based Sciences (iThemba LABS) in Johannesburg (South Africa) and at the Hertelendi Laboratory of
Environmental Studies (Isotoptech Zrt
and MTA ATOMKI), Debrecen (Hungary).
Action 1.2.2.
Stable isotope analysis (5000 segments). Stable isotope
analysis for determining the
δ13C and δ18O values were
performed at the Stable Isotope Laboratory of iThemba
LABS, Gauteng (South Africa).
Fig. 5. The
Fumba-1 baobab, which grows directly on the beach, has its lower part submerged
underwater from time to time.
Objective 1.3. Measuring and dating
trees of Romania, Moldova and Europe (I)
In July 2021, our research team undertook a trip to
the pasture of Mercheaşa village, Homorod commune, Braşov county. A
superlative pedunculate oak (Quercus
robur) located there was called the “Carpathian Elder”. This tree
experienced increased media attention over the last years, which included an
exaggerated age estimate of 900 years. The current measurements are: h = 17.6
m, cbh = 10.16 m, V = 50 m3. Dozens of daily visitors from all over
the country visit the tree, which is considered to be “the oldest of Romania”.
In order to dispel this myth, we collected samples for radiocarbon dating. The
dating results indicated that the oak of Mercheaşa has a real age of
around 560 years.
Fig.
6. The Mercheaşa oak has an age of “only” 560 years.
In October 2021, the research team travelled to the
Sadova village, a suburb of Cîmpulung Moldovenesc city, Suceava county, where a
centennial wych elm (Ulmus glabra)
can be found. The elm is in a degraded state, missing a large chunk of its
trunk. Furthermore, the trunk is mostly empty inside and only three branches of
the original crown remain (Fig. 7). The current measurements are: h = 13.8 m,
cbh = 6.77 m.
In the beginning of June, the research team travelled
to Tenerife island, Spain. Here the endemic dragon trees (Dracaena draco) were investigated. The most representative
specimens of the species were measured, with a special focus on the famous Icod
tree, also known as “El drago milenario”.
Fig. 7. The wych elm of Sadova.
Actions 1.3.1. Measuring 40
trees, 1.3.2. Collecting samples of 4 trees, 1.3.3. Pretreatment (20 segments)
and 1.3.4. AMS radiocarbon dating (20 segments).
A total of 56 trees were measured (compared to 40
envisaged), and samples were collected from 8 trees (compared to 4 envisaged),
30 segments (compared to 20 envisaged) were pretreated and subsequently
radiocarbon dated.
Objective 1.4. Dissemination of results.
Action
1.4.1. The writing or publishing of 2-3 scientific papers.
In 2021, we published 4 scientific
papers, all in ISI journals, out of which 2 are in the so-called red zone,
according to the CNCS classification system. All papers mention that „The research was funded by the Romanian Ministry of Education
CNCS-UEFISCDI under grant PN-III-P4-ID-PCE-2020-2567,
No. 145/2021.”
Action 1.4.2.
3-5 presentations at international Conferences, such as AMS-15 (Sydney),
Radiocarbon and the Environment (Gliwice) etc.
Due to the COVID-19 pandemic, the
scheduled conferences were postponed for the next year, except for the AMS-15
conference in Sydney, which took place online.
Action
1.4.3. The writing of the annual activity report. This activity refers to
the writing of the present report.
The contribution of the project to the development of human resources for research.
On the research team included a Ph.D. candidate, namely Roxana Pătruţ and a postdoctoral fellow, Dr. Ileana Raţiu.
The Ph.D. candidate partook in most (inter)national field trips, is a co-author of all 4 published papers and of the international AMS-15 conference presentation. In 2021, the Ph.D. candidate defended her thesis entitled
“The investigation of some superlative baobabs (Adansonia spp.) by AMS radiocarbon dating for assessing
the ages, architecture and growth rates, and by stable isotope analysis respectively, for climate study” (Ph.D. supervisor: Prof. Dr. Laszlo Rakosy), which was based on data
and results obtained via the current and previous research projects focusing on baobabs. In July 2021, she was granted the title of Doctor in Biology .
The postdoctoral researcher also partook in most field trips within or outside Romania. She is a co-author of all 4 published papers and of the AMS-15 conference presentation.
Conclusions
The information
presented above shows that the objectives mentioned in the unique phase of the
Project Implementation Plan for 2021 were fulfilled.
Additionally, all
envisaged results were obtained.
SCIENTIFIC AND TECHNICAL REPORT
on the
implementation of the project entitled
Radiocarbon dendrochronology, isotope dendroclimatology
and conservation of monumental angiosperm trees of the world
(Acronym RADACLIR)
Code
PN-III-P4-ID-PCE-2020-2567
Contract
No. PCE 145/2021
________________________________
for the period January - December
2022
SUMMARY OF
THE UNIQUE PHASE 2 (2022)
The project consists of 3 recurring
phases with identical designation, each with 4 identical objectives and similar
actions (action types). The differentiation is possible by the 1, 2 or 3 index, and I, II or III, respectively, which corresponds to
the three different years of the project period and also to the different
investigated areas and angiosperm species. Accordingly, the phase for 2022 is
called Phase 2 – The conservation and protection of monumental trees and their
radiocarbon dating and stable isotope analysis (II). The specific objectives of
Phase 2 concern the radiocarbon dating of baobabs (objective 2.1), the climate
study based on wood samples collected from baobabs and investigated by stable
isotope analysis (objective 2.2), the measurement and dating of angiosperm
trees in Romania and Europe (objective 2.3) and the dissemination of results
(objective 2.4).
The scientific
activities of the research project performed during the January-December 2022
implementation period pursued the fulfillment of the objectives mentioned in
the unique phase of the Project Implementation Plan for 2022.
Unique
phase 2 (2022): Conservation and protection of superlative trees and the AMS
radiocarbon investigation and stable isotope analysis of such trees (II).
Objective 2.1. Dating of baobabs (I).
Action 2.1.1. Sample
collection from 25 baobabs.
Objective
1.2. Climate study (I).
Action 2.2.1. Sample collection from 2 baobabs.
A number of 30
representative African baobabs (Adansonia
digitata) from Oman and Senegal were measured and investigated. Samples for
radiocarbon dating were collected from 28 specimens (compared to 25 envisaged)
and from 2 baobabs for stable isotope analysis, respectively (compared to 2
envisaged).
Two important
visits to Oman took place in April (3 persons) and in August 2022 (2 persons),
the second just during the south-east monsoon. Oman
has a very interesting and unexpected African baobab population. With one
exception, all baobabs are located in southern Oman, in the Dhofar
Governorate. Many researchers consider these baobabs an impressive botanical
reminder of Dhofar’s links with Africa.
The main investigation site is Wadi Hinna, a small semi-arid
valley (3 km2) at the edge of the Dhofar
Mountains (17º03' N, 54º36' E, altitude 300-360 m) and at 20 km from the
coastal plain. Wadi Hinna
hosts an unique water-limited cloud forest of African
baobabs (Fig. 1). The precipitation (annual rainfall 130 mm) falls almost
exclusively during the rainy season (mid-June to mid-September), in which moist
air from the Indian Ocean, i.e., the south-east monsoon (called khareef), encounters the mountains leading to clouds and
dense fog. The rainfall precipitation is significantly supplemented by
horizontal precipitation, namely cloud water interception within the canopy of
trees.
Fig.
1. The scenic entrance to the Baobab Forest of Wadi
Hinna.
The
106 trees of the Baobab Forest grow on a slope among huge stones of sedimentary
rocks, containing mainly limestone, which are moved by the force of water
during the rainy season. In recent years, Wadi Hinna was divided into two parts, located at lower and
higher altitudes, namely Wadi Hinna
and Wadi Hasheer, according
to the stratigraphic origin and composition. The trees have different shapes,
sizes and structures.
Fig. 2. The Grand
Baobab of Wadi Hinna during the dry season.
Fig. 3. The
Grand Baobab Tree of Wadi Hinna during the rainy season.
The Baobab Forest hosts a giant specimen, namely the
Grand Baobab Tree of Wadi Hasheer. It exhibits an open ring-shaped structure,
which consists of 12 fused stems (Fig. 2, 3). The measurements are: height h =
19.2 m, circumference (at 1.30 m above ground level) cbh = 21.35 m, total wood
volume V = 260 m3.
Being three
times bigger than any other tree from Wasi Hinna and Wadi Hasheer, the Grand
Baobab could be the Parent tree of all trees found in the Baobab Forest.
Another
representative baobab from the forest has the code name WHI-1605, after its
location (Wadi Hinna) and circumference (10.65 m). It exhibits an open
ring-shaped structure and is composed of 6 partially fused stems (Fig. 4). Its
dimensions are: h = 12.3 m, cbh = 16.05 m, V = 80 m3.
Fig. 4. The
baobab WHI-1605 is located right next to the entrance to Wadi Hinna.
The best known baobab of Oman grows completely
isolated in Dalkut, close to the border with Yemen. This baobab is named by the
locals “Hiroum Dheeri” (in Arabic, “the tree from far away”). Its dimensions
are: h = 13.5 m, cbh = 13.30 m, V = 50 m3. Its height was
reduced to only 7.5 m, after that the highest branch broke in 2019-2020.
Radiocarbon dating of a small fragment from the broken branch, still on the
ground, indicates that the baobab is over 700 years old. This value suggests
that the baobab of Dalkut was probably planted by an
African traveler who would have passed through the area many centuries ago. The
closest baobab to the one in Dalkut is in Wadi Hinna, at a distance of over
150 km.
Fig. 5. The
baobab of Dalkut in 2017, when its top was still intact.
In October 2022, the Project Manager paid a new visit
to Senegal, the country with the highest number of African baobabs in the
northern hemisphere. Here we present other two representative Senegalese
baobabs which were investigated.
Just behind the
Presidential Palace, next to a road to Cap Manuel and the tourist port of
Dakar, there is the so-called baobab of the President (Baobab du Président), traditionally called the Baobab from the
Cornice East (Baobab de la Corniche Est). It was originally located in a small
settlement on the outskirts Dakar, that was demolished
in the 1990s. The baobab has now reached the middle of an asphalted road which
covers its roots to a good extent and over which many hundreds of cars pass
daily (Fig. 6). This is one of the largest and oldest single-stemmed baobabs in
the world. The dimensions are: h = 14.7 m, cbh =
11.10 m, V = 65 m3 and its age is around 500 years. The very rich
canopy has 7 primary branches, out of which one is broken. Unfortunately, its
life cycle will be significantly shortened by the cars that drive around it and
the measures of conservation are practically impossible to take due to its
current position in an "official" area.
Fig. 6. The Baobab from the Cornice East of
Dakar is now located in the middle of a paved road, which is heavily
circulated.
Fig. 7. The Baobab of the Airport is located in the vicinity of
the International airport Dakar-Thiès.
At a distance
of 3.5 km from the International airport Blaise Pascal from Dakar-Thiès, in the middle
of a field with palm trees, we identified a superlative
baobab with an impressive volume. Because of its location, we named it the
Baobab of the airport (Fig. 7). It has a cluster structure and consists of 10
fused stems, out of which 2 are broken. Its dimensions are: h = 22.5 m, cbh = 20.25, V = 250 m3. It contains a
common/normal cavity in one of the stems. The age of the Baobab of the airport,
whose stems have different sizes and belong to different generations, is over
500 years.
Due to the
restrictions imposed by the COVID-19 pandemic, which were much more severe than
in Europe and which either did not allow foreign citizens to enter the country,
or required a mandatory quarantine for 10-14 days, certain trips to countries
such as Namibia, Angola, Madagascar, Australia, Brazil could not take place in
2022.
Actions
2.1.2. Pretreatment (60 segments), 1.1.3. AMS radiocarbon dating (60 segments)
and 1.1.4. Calibration (60 segments).
70 wood segments
were pretreated by the acid-base-acid or α-cellulose pretreatment method,
then AMS (accelerator
mass spectrometry) radiocarbon
dated and subsequently calibrated (compared to 60 envisaged).
The
radiocarbon dating by AMS was performed at the Hertelendi Laboratory of
Environmental Studies (Isotoptech Zrt
and MTA ATOMKI) of Debrecen (Hungary) and at the iThemba
Laboratory for Accelerator Based Sciences (iThemba
LABS) in Johannesburg (South Africa).
Action 2.2.2. Stable isotope analysis (5000 segments). The stable
isotope analysis for determining the δ13C and δ18O
values were performed at the Stable Isotope Laboratory of iThemba
LABS, Gauteng (South Africa).
Objective 2.3. Measuring and dating trees of
Romania, Moldova and Europe
(II)
In February 2022, a research team (3 members)
undertook a trip in
the area of Muncel village, which belongs to the Baia de Arieş mining town of
the Western Carpathians in Alba county, Romania. A monumental historic beech (Fagus sylvatica), called „The Emperor’s
Beech” (Fagul Împăratului),
can be found next to a forest road, on a hill at the height of around 40 m
above the right shore of the Arieş river, near
the Muncel village (Fig. 8). The name of the historic
tree comes from Franz Joseph I, the Emperor of Austria (1850 – 1918), who
visited Transylvania in 1852 and would have even seen the beech. The Emperor’s
Beech is also famous for its marcescent leaves which, although they dry up in the
fall and turn brown, remain preserved during the winter. The leaves do not fall
until the spring, when the new green leaves emerge. The cause of the marcescence is not yet sufficiently understood. Its
dimensions are: h = 23.2 m, cbh = 5.00 (5.33 m in
2009), V = 20 m3. According
to the radioarbon dating results, the Emperor’s Beech
is around 420 years old. In 1995, the historic tree was declared a Natural
Monument.
Fig. 8. The impressive
canopy of the Emperor’s Beech, with marcescent
leaves.
In
July 2002, a member of the research team visited areas from the continenetal and insular Greece. On this occasion, several
representative specimens of oriental planes (Platanus orientalis) and olive trees (Olea europea)
were investigated an measured.
Actions 2.3.1. Measuring 30
trees, 2.3.2. Collecting samples from 3 trees, 2.3.3. Pretreatment (20
segments) and 2.3.4. AMS radiocarbon dating (20 segments).
A total of 35 trees were measured (compared to 30
envisaged), and samples were collected from 5 trees (compared to 3 envisaged),
25 segments (compared to 20 envisaged) were pretreated and subsequently
radiocarbon dated.
Objective 2.4. Dissemination of results.
Action
2.4.1. The
writing or publishing of 3-5
scientific articles in ISI indexed journals.
In 2022, we submitted for publication 6
scientific articles, all in ISI indexed journals, out of which 2 are in the
so-called red zone, according to the CNCS classification system. All articles
mention that „The research was funded by the
Romanian Ministry
of Education CNCS-UEFISCDI under grant
PN-III-P4-ID-PCE-2020-2567, No. 145/2021.” The 6 articles are the following:
1. A. Pătruţ, R.T.
Pătruţ, V. Bocoş-Binţinţan,
I.A. Raţiu, L. Rakosy,
G. Zdrob, E. Vancă,
K.F. von Reden, Radiocarbon investigation of two old
elms from Romania, Studia UBB Chemia, 2022,
LXVII, 1, 245-256. (doi:
10.24193/subbchem.2022.1.16).
2. A. Pătruţ, R.T.
Pătruţ, L. Rakosy,
I.A. Raţiu, N. M. Nassor,
K.F. von Reden, Radiocarbon investigation of two
large African baobabs from Kizimkazi, Zanzibar,
Tanzania, Studia
UBB Chemia, 2022, LXVII, 3, 143-153. (doi: 10.24193/subbchem.2022.3.09).
3. A. Pătruţ, R.T.
Pătruţ, L. Rakosy,
W. Oliver, I.A. Raţiu, D.A. Lowy, G. Shiimbi, S. Woodborne, K.F. von Reden, Radiocarbon Investigation of the Historic African
Baobabs of Omusati, Namibia, Forests, 2022, 13, 1899. (doi.org/10.3390/f13111899).
4. A. Pătruţ, V. Bocoş-Binţinţan, R.T. Pătruţ,
D. Parţilă, I.A. Raţiu,
L. Rakosy, K.F. von Reden,
Radiocarbon dating of the historic Emperor’s Beech from Muncel,
Baia de Arieş,
Romania. Studia UBB Chemia, 2022, LXVII, 4. (doi: 10.24193/subbchem.2022.4.11).
5. R.T. Pătruţ, A.
Garg, A. Pătruţ, S. Woodborne,
L. Rakosy, I.A. Raţiu,
The first radiocarbon investigation of the Indian banyan
(Ficus benghalensis
L.). Current Science.
6. R.T. Pătruţ, S. Woodborne, A. Pătruţ,
G. Hall, I. Robertson, C.W. Winterbach, L. Rakosy, I.A. Raţiu, A
900-Year Isotopic Proxy Rainfall Record from Central Botswana. Radiocarbon.
The
abstracts of the 6 articles are:
1.
Radiocarbon investigation of two old elms from
Romania.
ABSTRACT. The paper reports the AMS (accelerator
mass spectrometry) radiocarbon investigation results of two superlative elms
from Romana, the very large field elm of Calafat,
with a wood volume of 85 m3, and the wych
elm of Sadova. Two wood samples were extracted from
each elm and were analysed by AMS radiocarbon. The
oldest dated sample from the elm of Calafat had a radiocarbon date of 350 ± 19
BP, which corresponds to a calibrated age of 415 ± 25 years, while the oldest
sample from the elm of Sadova had a radiocarbon date
of 188 ± 24 BP, corresponding to a calibrated age of 260 ± 25 years. These
values indicate high ages for the two elms, namely 430 ± 25 years or the elm of
Calafat and 400 ± 25 years for the elm of Sadova.
2. Radiocarbon
investigation of two large African baobabs from Kizimkazi,
Zanzibar, Tanzania.
ABSTRACT. The article
reports the AMS
(accelerator
mass spectrometry) radiocarbon dating results of Kizimkazi
Big tree and Kizimkazi II baobab, two large African
baobabs from Zanzibar, Tanzania. Unfortunately, both baobabs toppled and died
in 2020 and 2018 during violent storms. The investigation of the two baobabs
evinced that the first of them, which was also the biggest tree of Tanzania,
consisted of 5 stems, out of which 2 were false ones, and had a closed
ring-shaped structure. The second baobab was composed of 4 fused stems and had
a cluster structure. Several wood samples were collected from the two baobabs.
Seven segments were extracted from the samples and dated by radiocarbon. The
oldest segment from Kizimkazi Big tree had a
radiocarbon date of
312 ± 18 BP, corresponding to a calibrated age of 380 ± 10 calendar years.
According to dating results, the Kizimkazi Big tree
died at the age of 400 ± 25 years. The oldest segment from Kizimkazi
II baobab had a radiocarbon date of 137 ± 17 BP, corresponding to a
calibrated age of 190 ± 10 calendar years. This value indicates that the Kizimkazi II baobab was 250 ± 25 years old when it died.
3. Radiocarbon Investigation of the Historic African
Baobabs of Omusati, Namibia.
ABSTRACT. The Omusati
region belongs to the historic Ovamboland, an area of
northern Namibia populated by tribes of the Ovambo
group. Four very large African baobabs of Omusati
played an important role in historic events of the area, such as the tribal
wars and the Namibian War of Independence. The four historic baobabs are Ombalantu baobab (8 stems; circumference 24.50 m), Okahao baobab (4+ stems; around 25 m), Amadhila
baobab (12 stems; 25.35 m) and Sir Howard baobab (9 stems; 31.60 m). Two
historic baobabs collapsed totally or partially. The stems of Amadhila baobab toppled and died in 2021, while 3 stems of Okahao baobab collapsed long time ago, but are still alive.
Our research aimed to determine the architecture and age of these baobabs.
Three baobabs (Ombalantu, Amadhila,
Sir Howard) exhibit a closed ring-shaped structure,
with a false cavity inside. One baobab (Okahao) had
an open ring-shaped structure, before its collapse. Several wood cores were
extracted from the baobabs and investigated by radiocarbon dating. The dating
results indicate ages of 770 ± 50 years years for Ombalantu baobab, 650 ± 50 years for Okahao
baobab, 1100 ± 50 years for Amadhila baobab and 750 ±
50 years for Sir Howard baobab.
4.
Radiocarbon dating of the historic Emperor’s Beech
from Muncel, Baia de Arieş, Romania.
ABSTRACT. The article reports the AMS
(accelerator mass spectrometry) radiocarbon dating results of the historic
Emperor’s Beech from Muncel, Baia
de Arieş, Romania. Two wood samples were
collected from the large tree, out of which four segments were extracted and analysed by AMS radiocarbon. The oldest dated sample
segment had a radiocarbon date of 233 ± 18 BP, which corresponds to a
calibrated age of 365 ± 5 years. This value sugests an age of 420 ± 20 years for the Emperor’s Beech.
Thus, the historic beech started growing around the year 1600.
5. The
first radiocarbon investigation of the Indian banyan (Ficus
benghalensis L.).
ABSTRACT. The paper discloses the
first radiocarbon investigation of Ficus benghalensis, which was performed on the large Indian
banyan of Narora. The banyan was discovered during
floristic surveys in the Upper Ganga Ramsar Site,
Uttar Pradesh, India and ranks as the tenth largest banyan in the world by its 4069 m2 crown
spread. The tree has a unique architecture, with just four prop roots
supporting the main stem. The oldest sample was found
to be 346 ± 40 BP, which corresponds to a calibrated age of 425 ± 35 calendar
years. The radiocarbon dating results indicate an age of 450 ± 50 years
for the Indian banyan of Narora. The age value represents the oldest accurate dating
result for the species. Several protection measures are included to ensure the
long-term survival of this archaic tree.
6.
A 900-Year Isotopic Proxy Rainfall Record from Central Botswana.
ABSTRACT. High resolution climate
archives for southern Africa are essential for designing and validating climate
projections. For southern Africa and Botswana in particular, the interannual rainfall variability is associated with sea
surface temperatures in the Agulhas Current Core region, which determine the
east-west displacement of tropical temperate troughs (TTTs). Stable carbon
isotope analysis and radiocarbon dating of the African baobab (Adansonia digitata L.)
can provide reliable reconstructions of rainfall variability in its
distribution area. We obtained a proxy rainfall record for central Botswana
based on the historic Chapman baobab, which collapsed in 2016 during an intense
El Niño event. The two investigated samples of the oldest stems of the baobab, which
exhibited an open ring-shaped structure composed of 6 stems, provide insight
into the precipitation regime over the last millennium, showing centennial and
decadal scale variability. The results indicate that the lowest rainfall
occurred during the Little Ice Age (1300-1350), while the Warm Medieval Period
was marked by relatively stable precipitation. Previous studies suggested
positive sea surface temperature (SST) anomalies in the Mozambique Channel led
to an eastward movement of the TTTs but our proxy record shows a westward
displacement in the past, causing drought in north-eastern South Africa and
wetter conditions in the central part of southern Africa. The positive rainfall
correlation with SST anomalies and ENSO reversed after 1900, causing a gradual
decrease in precipitation and confirming the current aridity trend for
Botswana.
The
first 4 articles were published in 2022, article 5 is
waiting a final decision from the reviewers, while article 6 will be evaluated
by the reviewers.
Action
2.4.2. 1-2 presentations at International
Conferences.
Due to the COVID-19 pandemic, the 24th
Radiocarbon Conference, scheduled for
2021, was postponed. The Conference took place at ETH Zürich (Schwitzerland) between September 11-18,
2022. Two members of the research team participated at this conference
with the following presentations:
1. A. Pătruţ,
M. Molnar, R.T. Pătruţ, L. Rakosy, I.A. Raţiu, D. Rakosy, J.J. Brown, T. Varga, AMS
Radiocarbon investigation of the African baobabs from the semiarid cloud forest
of Wadi Hinna, Dhofar, Oman.
2.
R.T. Pătruţ, S. Woodborne, A. Pătruţ,
G. Hall, I. Robertson, C.W. Winterbach, L. Rakosy, I.A. Raţiu, A
900-Year Isotopic Proxy Rainfall Record from Central Botswana.
Action 2.4.3. The writing of the annual activity
report.
This activity refers to the writing of the present report.
The contribution of the project to the development of human resources for research.
Since the beginning of the project the research team a Ph.D. candidate, namely Roxana Pătruţ, and a postdoctoral researcher, Dr. Ileana Andreea Raţiu.
In 2021, the Ph.D. candidate defended her thesis, which was based on data and results obtained via the current and previous research projects focused on baobabs. She also was granted the title of Ph.D. in biology.
In 2022, Dr. Roxana Patrut participated at field investigations in Romania and Oman, is a co-author of all 6 mentioned scientific articles and of the 2 presentations at the 24th Radiocarbon Conference.
The postdoctoral researcher also participated at field investigations in Romania and at the 24th Radiocarbon Conference in Schwitzerland.
She is a co-author of the 6 mentioned scientific articles and of the 2 presentations at the Radiocarbon Conference.
CONCLUSION
The
information presented above shows that all objectives mentioned in the unique
phase of the Project Implementation Plan for 2022 were fulfilled. Additionally,
all envisaged results were obtained.
