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Age, growth and architecture of monumental angiosperm trees assessed by AMS radiocarbon investigation and climate research performed by stable isotope analysis of wood samples collected from such trees
Investigarea vârstei și arhitecturii unor arbori angiospermi monumentali prin datare cu radiocarbon, respectiv studiul climatic al mostrelor recoltate din acești arbori prin analiză de izotopi stabili

2017

SCIENTIFIC AND TECHNICAL REPORT

on the implementation of the project entitled

 

Age, growth and architecture of monumental angiosperm trees assessed by AMS radiocarbon investigation and climate research performed by stable isotope analysis

of wood samples collected from such trees

 

Code PN-III-P4-ID-PCE-2016-4-0776

Grant No. 90/2017

________________________________

for the period August - December 2017

 

The scientific activities of the research project pursued the fulfillment of the objectives mentioned in the unique phase of the Project Implementation Plan for 2017.

Unique phase 1 (2017): The investigation of superlative trees by AMS radiocarbon dating and stable isotope analyses.

 

Objective 1.1. Baobab dating (1)

Activity 1.1.1. Investigation of 7 baobabs. A number of 25 African baobabs (Adansonia digitata) from Namibia and South Africa were measured and investigated.

Our research team, composed of 3 members, paid a first visit to Namibia (04.09-17.09) and covered around 2500 km in order to investigate the regions with a high density of monumental baobab specimens. These regions are positioned in the eastern area (Otjozondjupa province, close to Tsumkwe town) and in the northern area (Omusati province, in the Outapi-Tsandi-Onesi triangle).

We followed the evolution and updated the status of the famous Holboom baobab, located close to Tsumkwe in the Nyae Nyae Conservancy, whose decline started in 2012, when the entire left (western) arm/stem collapsed and the cavity walls broke off. Holboom had the largest circumference of all baobabs, i.e., cbh = 35.10 m, currently reduced to 31.87 m, respectively the biggest height, namely h = 30.2 m, currently reduced to 21.0 m. A wood sample collected previously from this specimen was dated to a radiocarbon age of 1760 ± 18 BP, which correspons to a calibrated age of 1700 ± 60 calendar years. This value suggest an age of at least 1800 years for the oldest part of the tree. The current state of Holboom evinced that the 2 closed ring-shaped structures are decomposing fast (Figure 1). We consider that the impressive baobab will totally collapse over the next years, thus adding to the list of monumental baobabs that have died recently.

 

Figure 1. Holboom in August 2017, showing its collapsed stems and the broken cavity walls.

       

Figure 2. Makuri Leboom, with the outlying buildings around its stems.

Another monumental specimen, the Makuri Leboom, is also located in the Nyae Nyae Connservancy and is practically known only by the native San population. The baobab has an open ring-shaped structure and is composed of 12 stems which belong to 3 generations of different ages. Two stems are lying on the ground, 4 stems are broken and 6 stems have several missing branches (Figure 2). The Makuri Leboom baobab has a very impressive circumference cbh = 34.23 m; the maximum height of its standing trunks is only h = 14.5 m.

Figure 3. The Okahao baobab was declared a National Monument of Namibia in 2013.

In the Omusati province, our team first visited Okahao to investigate an interesting tree, considered a symbol of the Namibian struggle for independence. The baobab possesses an open ring-shaped structure which consists of 4 units; only the largest unit is standing upright, while the other 3 toppled more than a century ago. The collapsed units are still alive and new stems emerged at their tops. The measurements provided the following values: restored cbh around 25 m,  h = 15.7 m.

The highest density of monumental baobabs can be found in the area of Outapi town. There are 6 baobabs with a cbh of over 20 m positoned over a distance of only 5 km. One of the most interesting specimens is located in the Anamulenge suburb. The Anamulenge-1 baobab has a closed ring-shaped structure, which is composed of 11 almost perfectly fused stems, out of which 4 are false ones. A number of 4 stems define a false cavity, that has a tall entry located at 4 m above ground (Figure 4). Our investigations provided the following measurements: cbh = 25.33 m, h = 19.2 m.

Figure 4.  The Anamulenge-1 baobab is one of the largest individuals in the Outapi area.

The area around the Onesi settlement is home to a clump of baobabs. Our research team has identified 3 baobabs with a cbh over 22 m. The biggest specimen, Onesi-1, possesses a closed ring-shaped structure with a false cavity. The cavity has a tall opening at the height of 4 m. The baobab currently consists of 8 fused stems and a stem is missing in the central area of the trunk (Figure 5). The measurements provided the following values: cbh = 25.30 m, h = 17.5 m.

One team member performed research and investigations in South Africa (04.10-19.11), including laboratory analyses and field work. Seizing this opportunity, the famous Platland baobab a.k.a. Sunland baobab was visited once again. The Platland baobab had a closed double ring-shaped structure, with two distinct units that consisted of 5 and 3 stems, respectively. It was the baobab with the largest wood volume of all angiosperm trees, i.e., V = 501 m3. Since 2016, the giant baobab split four times and the largest unit toppled completely. The last of its 5 stems collapsed on November 6 2017 (Figure 6).

Figure 5. The Onesi-1 baobab.

 

Figure 6. The Platland / Sunland baobab in November 2017, after all stems of the large unit collapsed.

 

Activity 1.1.2. Pretreatment of samples (14 segments), 1.1.3. Radiocarbon dating by AMS (14 segments) and 1.1.4. Calibration (14 segments). The 3 activities are associated, because the first one precedes and the last one is subsequent to radiocarbon dating. The number of pretreated, dated and calibrated samples was 30 (as compared to 14 envisaged).

The radiocarbon dating by AMS (accelerator mass spectrometer) was performed at the Atomki Hertelendi Hekal AMS Laboratory in Debrecen (Hungary) and iThemba Laboratory for Accelerator Based Sciences (iThemba LABS) in Johannesburg (South Africa).

 

Objective 1.2. Climate study (1)

Activity 1.2.1. Collecting samples from 2 trees; 1.2.2. Pretreatment (2000 segments); 1.2.3. Stable isotope analysis (2000 segments).  For the climate study, samples from 5 baobabs and camel thorn trees were collected (as compared to 2 envisaged). A member of the research team went to the Stable Isotope Laboratory at the University of Pretoria (South Africa) (04.10-19.11), where she pretreated 2400 wood samples by using the acid-base-acid method (as compared to 2000 envisaged). She also took part in the stable isotope analysis of the 2400 pretreated samples (as compared to 2000 envisaged) by IRMS (isotope ratio mass spectrometer) Delta V Plus.

 

Objective 1.3. Measuring and dating trees of Romania and Europe (1)

Activity 1.3.1. Complete measurements of 10 trees 1.3.2; Collecting samples from one tree. Complete measurements of 24 trees were performed (as compared to 10 envisaged). The investigated tree species were the following: pedunculate oak (Quercus robur), sessile oak (Quercus petraea), ash (Fraxinus excelsior), black poplar (Populus nigra), white poplar (Populus alba), small-leaved lime (Tilia cordata) from Romania, Hungary and Germany. Samples from 5 trees were collected (as compared to 1 envisaged), including the black poplar of Mocod, the oldest specimen of its species which collapsed after a violent storm in April 2017.

 

Objective 1.4. Dissemination of results.

Activity 1.4.1. The writing of 1-2 scientific articles and submitting them to ISI journals.

By the end of December 2017, when the current unique phase will end, a minimum of 3 articles will be submitted (as compared to 1-2 envisaged). Two articles mention that „this research was supported by the Romanian Ministry of Research and Innovation CNCS-UEFISCDI under grant PN-III-P4-ID-PCE-2016-0776, Nr. 90/2017” and one of them includes the following statement: „part of this research was supported by the Romanian Ministry of Research and Innovation CNCS-UEFISCDI under grant PN-III-P4-ID-PCE-2016-0776, Nr. 90/2017.”

We also plan to submit a fourth article entitled „Age and growth of the largest Senegalese baobabs” (authors: Adrian Pătruţ, Roxana Pătruţ, Oumar Ka, Daniel Lowy, Stephan Woodborne, Sébastien Garnaud, Karl von Reden) by the end of 2017 to journals such as Tree Physiology and Annals of Forest Science.

Activity 1.4.2. Participating at the international scientific conference with 1-2 presentations (Ottawa, Canada). Two members of the research team attended the important international AMS-14 conference, which represents one of the two major events dedicated to radiocarbon dating that occur once in 3 years. This year, AMS-14 took place in Ottawa (Canada) in the time frame 12-20.08.2017. The team members prepared and delivered 3 presentations (as compared to 1-2 envisaged).

Activity 1.4.3. Participating at the international PMIP4 conference (Stockholm, Suedia) with 1 presentation. A team member participated at the PMIP4 conference (Paleoclimate Modeling Intercomparison Project, Phase 4) in Stockholm (Sweden), with 1 presentation (1 envisaged) during 25-29.09.2017.

Activity 1.4.4. Participating at the international CMSE 2017 conference with 0-1 presentations (Beijing, China). In March, the project manager was contacted by the organising committee of the CMSE (Global Conference of Materials Science and Engineering) to participate as an „invited speaker” and also as a chair for a session at the Beijing meeting in October 2017. The preliminary invitation has been accepted, but the announcement regarding the start of the IDEI research projects of the 2016 competition was delayed until mid July 2017. By that time, the organising committee regarded the final acceptance of the invitation as late due to the conference program being already set. However, they renewed the invitation for the 2018 conference.

Activity 1.4.5. The writing and publication of a book about investigating and radiocarbon dating African monumental baobabs. In July, we reached an understanding with „Casa Cărţii de Ştiinţă” press regarding the publication of the book „Baobabi superlativi investigaţi prin datare cu radiocarbon” (Superlative African baobabs investigated by radiocarbon dating) (authors: Adrian Pătruţ, Roxana Pătruţ, Laszlo Rakosy), of about 120-130 pages. Subsequently, the authors decided to include the results obtained in 2017 and to increase the page number by also adding new trees and additional photographs. The book is in its final preparation stage and will present over 100 high-resolution color figures that also imply special printing conditions. The book will be printed in 2018.

Activity 1.4.6. The writing of the annual activity report. This activity refers to the writing of the present report.

 

Conclusions

The information presented above proves that the objectives mentioned in the unique phase of the Project Implementation Plan for 2017 have been fulfilled. Additionally, the envisaged results have been obtained.

 

Project manager,

Prof. dr. Adrian Pătruţ

 

2018

SCIENTIFIC REPORT

on the implementation of the project entitled

 

Age, growth and architecture of monumental angiosperm trees assessed by AMS radiocarbon investigation and climate research performed by stable isotope analysis of

wood samples collected from such trees

 

Code PN-III-P4-ID-PCE-2016-4-0776

Grant No. 90/2017

________________________________

for the period January - December 2018

 

The scientific activities of the research project pursued the fulfillment of the objectives mentioned in the unique phase of the Project Implementation Plan for 2018.

Unique phase 2 (2018): The investigation of superlative trees by AMS radiocarbon dating and stable isotope analyses (II).

Objective 2.1. Dating baobabs and Vachellia erioloba specimens (II).

Activity 2.1.1. Sample collection from 26 baobabs and 3-5 V. erioloba. A number of 50 African baobabs (Adansonia digitata)  and Grandidier’s baobabs (A. grandidieri) from South Africa, India and Madagascar were measured and investigated. Wood samples were collected from 30 specimens (as compared to 26 specimens envisaged). On the other hand, samples were collected a priori from 5 V. erioloba individuals during the trip to Namibia in September 2017 (as compared to 3-5 specimens envisaged).

One team member performed research and investigations in South Africa (May-June 2018), including lab analyses and field work. The first visited specimen was the famous Platland (Sunland) baobab, which was the largest known African baobab, with a total wood volume V = 501 m3. The tree had a double closed ring-shaped structure consisting of 2 distinct units. The largest unit, composed of 5 perfectly fused stems, completely toppled in November 2016. The smaller unit, defined by 3 stems, survived the event, although it was damaged during the collapse of the larger unit (Figure 1). 

 

 

Figure 1. Photo of the Platland baobab, showing the collapsed and broken stems of the largest unit and the surviving smaller unit.

Figure 2. The Leydsdorp baobab has a false cavity inside, which used to host a bar. 

 

Another millenial specimen was also visited, namely the Leydsdorp baobab near Gravelotte. This tree is famous especially because it hosted a bar called club Murchinson inside the fasle cavity during the last decades of the 19th century. The bar was frequently visited by prospectors and workers labouring in the gold mine close by, which was subsequently shut down. The baobab has a height of h = 21.5 m, a circumference at breast height (cbh) meaning at 1.30 m  above ground level cbh = 19.22 m and a total wood volume of V = 230 m3. It possesses a closed ring-shaped structure built by 4 perfectly fused stems disposed around a false cavity with a small opening (Figure 2).

Figure 3. General view of the Jhunsi baobab, near Allahabad.

Our research team, composed of 3 members, paid a also visit to India (September 2019) in the state Uttar Pradesh, which hosts several remarkable African baobabs. The research trip took place at the request of the Botanical Survey of India, with their support and the permission of the National Biodiversity Authority of India.

A sacred baobab is located in the small Muslim settlement Jhunsi, a suburb of Allahabad. The specimen grows only 50 m away from the left shore of the Ganga river, right next to the grave of a saint sufi from the 14th century. The baobab has not been left unscathed throughout the ages, having broken or missing branches, stem parts missing/gone and many decay cavities. The tree has also been damaged during the Kumbh Mela event in 2013, when it was partly set on fire. The baobab exhibits a cluster structure composed of 6 old stems and a younger stem, all perfectly fused together (Figures 3 and 4). Our investigations provided the following measurements: h = 14.0 m, cbh = 18.27 m, V = 130 m3. The reconstructed cbh (before the fire) is ca. 21.20 m.

Figure 4. The image depicts the stems of the Jhunsi baobab, which were damaged during a fire in 2013.

 

Another sacred and very spectacular baobab is the Parijaat tree of Kintoor, Barabanki district. This individual is worshipped by the local Hindu population, who believe that the baobab was planted by Lord Krishna himself about no less than 5000 years ago, and is a unique representant of its kind. The baobab of Kintoor is spectacular especially due to its huge canopy, with branches that reach diametres up to 2 m. The branch sizes are exaggerated in comparison with the relatively  modest trunk size. The specimen is protected by a metal fence and has a small temple at its base, dedicated to Lord Krishna. The measurements are: h = 13.2 m, cbh = 12.69 m. Due to a broken/fractured stem, the cbh was reduced by ca. 0.50 m. The total wood volume is only 80-90 m3, out of which around half was attributed to the canopy (Figure 5 and 6).

 

Figure 5. General view of the Parijaat tree of Kintoor.

Figure 6. A different view of the Kintoor baobab, highlighting its huge branches.

For monumental trees, the most important event in 2018 was the demise of the largest baobab in the world, namely Tsitakakoike, which is a Grandidier’s baobab (Adansonia grandidieri). Seizing the scientific opportunity, a small research party visited souteastern Madagascar, the Morombe area, for field investigations and sample collection (October 2018).

Fig. 7. The current state (October 2018) of the sacred baobab Tsitakakoike.

 

Tsitakakoike, the sacred baobab of Andombiro, partially broke and collapsed at the end of February 2018. Around 40% of its trunk and canopy is still standing, but they will also collapse soon (Figure 7). In 2013, when we investigated and dated the baobab, we reported the following dimensions: h = 14.6 m, cbh = 27.36 m, total V = 455 m3. The new measurements indicate that the volume could have been even bigger, about 500 m3 and the fallen branches had diametres up to 3.2 m. In our scientific paper published in 2015, we mentioned that Tsitakakoike has a closed ring-shaped structure, consisting of 5-6 stems disposed around a very large false cavity, which was fully closed and inaccessible. After the trunk split, our theory was confirmed, unveiling a huge false bell-shaped cavity with the following dimensions: the base of 6.50 x 6.10 m and the height was 7.80 m. The total volume of the false cavity would have been at least 175 m3 (Figure 8).  According to locals, Tsitakakoike broke and collapsed after more than 3 years without any rainfall in the Andombiro area.

Figure 8. Picture of the large false cavity of the Tsitakakoike baobab, taken from a height of 5 m.

 

“Le roi est mort, vive le roi!” (The king is dead, long live the king!). The population of Andombiro has also promoted Tsitakakoike as a tourist attraction, charging a fee for visiting the majestic baobab. When the specimen will collapse entirely, they shall burn the remains and transfer its soul into a new baobab, which will become the “next Tsitakakoike”. This is important in order to preserve the ancestral traditions involving the baobab, but also to maintain the income provided by tourism.

We were able to identify this new Tsitakakoike, whose location is still kept secret, in Ankoabe, only 1-2 km away from Andombiro. Our investigations provided the following measurements: h = 15.2 m, cbh = 28.70 m (Figure 9). Although the baobab of Ankoabe has a larger circumference than its predecessor, Tsitakakoike, its total volume is somewhat smaller.    

 

Figure 9. General view of the baobab of Ankoabe, which will become the “new Tsitakakoike”.

Activity 2.1.2. Pretreatment of samples (50-70 segments), 2.1.3. Radiocarbon dating by AMS (50-70 segments) and 2.1.4. Calibration (50-70 segments). The 3 activities are associated, because the first one precedes and the last one is subsequent to radiocarbon dating. During our field trips, samples from 30 baobabs were collected (compared to 26 envisaged). The number of pretreated, dated and calibrated segments obtained from the samples was 75 (as compared to 50-75 envisaged).

The radiocarbon dating by AMS (accelerator mass spectrometer) was performed at the Atomki Hertelendi Hekal AMS Laboratory in Debrecen (Hungary) and iThemba Laboratory for Accelerator Based Sciences (iThemba LABS) in Johannesburg (South Africa).

 

Objective 2.2. Climate study (II) with possible field trips to South Africa, Mozambique, Angola, Zimbabwe and Botswana (for 1-3 persons)

Activity 2.2.1. Collecting samples from 5 trees; 2.2.2. Pretreatment (4000 segments); 2.2.3. Stable isotope analysis (4000 segments).  For the climate study, samples from 5 African baobabs and Grandidier’s baobabs from Madagascar were collected (compared to 4 envisaged). A number of 4100 wood samples were pretreated by using the acid-base-acid method (as compared to 4000 envisaged). Following the pretreatment, the 4100 samples were subsequently investigated by stable isotope analysis (as compared to 4000 envisaged) by IRMS (isotope ratio mass spectrometer) Delta V Plus. The stable isotope analysis was performed at the University of Pretoria (South Africa).

Objective 2.3. Measuring and dating trees of Romania and Europe (II) with possible field trips in Romania (Bucureşti, Mocod, Merchiaşa, Oradea, Cajvana, Sighişoara, Iaşi, Rafaila, Merchiaşa, Botoşana, Aiton, Ţebea, Blaj, Arad, Simeria) and Europe (Moldavia, Hungary, Poland, Germany, Italy, France, Spain, Portugal, Danemark, Austria, Serbia, Macedonia, Greece, Turkey, Georgia) (for 1-3 persoans).

Activity 2.3.1. Complete measurements of 20 trees and 2.3.2. Collecting samples from 2 trees. Complete measurements of 25 trees were performed (as compared to 20 envisaged) from Romania, Hungary, Poland and Germany. The investigated tree species were the following: pedunculate oak (Quercus robur), sessile oak (Quercus petraea), ash (Fraxinus excelsior), black poplar (Populus nigra), white poplar (Populus alba), Oriental plane (Platanus orientalis), and small-leaved lime (Tilia cordata) from Romania, Hungary and Germany. Samples from 6 trees were collected (as compared to 2 envisaged).

Objective 2.4. Dissemination of results.

 

Activity 2.4.1. The writing of 4-5 scientific articles and submitting or publishing them in ISI journals.

In 2018, we published a number of 4 scientific papers and 2 additional articles were submitted to ISI journals and are under review (compared to 4-5 envisaged). Five articles mention that „this research was supported by the Romanian Ministry of Research and Innovation CNCS-UEFISCDI under grant PN-III-P4-ID-PCE-2016-0776, No. 90/2017” and one of them includes the following statement „part of this research was supported by the Romanian Ministry of Research and Innovation CNCS-UEFISCDI under grant PN-III-P4-ID-PCE-2016-0776, No. 90/2017.”

The 4 published articles in 2018 are the following:

1. S. Woodborne, G. Hall, C.J. Jones, N. Loader, A.Pătruţ, R.T. Pătruţ, I. Robertson, S.R.Winkler, C. Winterbach, A 250-year isotopic proxy rainfall from southern Botswana, Studia UBB Chemia, 2018, LXIII, 1, 109-123.

2. A. Pătruţ, S. Woodborne, R.T.. Patrut, L. Rakosy, D.A. Lowy, G. Hall, K.F. von Reden, The demise of the largest and oldest African baobabs, Nature Plants, 2018, 4, 423-426.

3. A. Pătruţ, R.T. Pătruţ, L. Rakosy, I.A. Raţiu, D.A. Lowy, J. Bodis, K.F. von Reden, Radiocarbon dating of the old ash of Aiton, Romania, Studia UBB Chemia, 2018, LXIII, 3, 41-48.

4. A. Pătruţ, N. Robu, V. Savu, R.T. Pătruţ, L. Rakosy, I.A. Raţiu, D.Lowy, D. Mărgineanu, K.F. von Reden, Radiocarbon investigation of the pedunculate oak of Botoşana, Studia UBB Chemia, 2018, LXIII, 4, 7-14.

 

The most important achievement of our research team this year must be the publishing of the article „The demise of the largest and oldest African baobabs” in the prestigious journal Nature Plants (impact factor 11.471).

The article discloses some of the main findings of our/my research team concerning the architecture, age and growth of monumental African baobabs. Practically, we have investigated all or almost all known monumental African baobabs in the tropics. Our main finding shows that, since 2005, 9 of the oldest and 5 of the 6 largest African baobabs have died or at least their oldest parts/stems have died. Given the lack of an epidemic, this fact is quite surprising, especially when taking into account that the age limit is well over 2000 years. All these remarkable trees, which have died are located in southern Africa. We suspect that their demise can be associated at least in part with recent climate change, which affects southern Africa in particular, due to an intensification of the El Niño effect of the ENSO index. This allowed an unprecedented combination of two major factors, namely high temperaturees and severe, prolonged drought, which determined or facilitated the demise of the largest and oldest African baobabs. 

These investigations were fully funded by the Ministry of Research and Innovation CNCS-UEFISCDI under grant PN-III-P4-ID-PCE-2016-0776, No. 90/2017. On the other hand, we are the only research team in the world, which has been performing for more than a decade such pioneer(ing) studies/work.

The paper published in Nature Plants had an unusual media coverage and reached a very high altmetric score. The article was announced by Sarah Hausman, the press officer of the Nature publishing group, on June 4, when the content of the article was made available through a press release. Our paper was under embargo until June 11, the official date of the online publishing. Since June 5, my research team and I started receiving tens of requests on a daily basis. Journalists from all over the world were requesting interviews and answers concerning our article either by phone, skype or email. On June 19, the same Sarah Hausman emailed me, highlighting the extraordinary interest of the public in our article. This is an original excerpt of the email:

Dear Dr. Patrut,

Hope this finds you well.

I wanted to send you an email regarding the fantastic media coverage of your baobab paper. 

Your research was the subject of 1058 articles, with stories from BBC, CNN, Guardian, the Times, Independent, Daily Mail, AFP, Deutsche Welle, USA Today, Washington Post, Los Angeles Times, the Atlantic, Newsweek,  New Scientist, Science, National Geographic, IFL Science, Mashable, Boing Boing, Earther, Business Insider, among others.

Coverage also appeared in New York Times online and in today’s print NYT Science Times section.

All the best,

Sarah Hausman

Communications and Press Officer, Nature Research

Springer Nature

 

On July 22, the article reached a high altmetric score of 2269, which measures the public attention and interest it stirred. This very high score ranked our article first of the 705 articles published by Nature Plants. It was also ranked 18th out of a number of 211001 articles published by all major scientific journals measured.

 

Activity 2.4.2. Participating at the international scientific Radiocarbon 23 conference with 1-2 presentations (Trondheim, Norway). Two members of the research team attended the important International Radiocarbon 23 Conference, which represents one of the two major events dedicated to radiocarbon dating that occur every 3 years. In 2018, the international Radiocarbon 23 conference took place in Trondheim (Norway) in the time frame 17-22.06.2018. The team members prepared and delivered 2 presentations (as compared to 1-2 envisaged).

 

The 2 presentations are the following:

 

A. Adrian Patrut, Roxana T. Patrut, Laszlo Rakosy, Karl F. von Reden, Daniel A. Lowy, Dragos Margineanu: AMS radiocarbon dating of very large African baobab trees from Savé Valley, Zimbabwe

 

B. Roxana T. Patrut, Adrian Patrut, Stephan Woodborne, Laszlo Rakosy, Karl F. von Reden, Daniel A. Lowy, Grant Hall, Ileana-Andreea Ratiu: Main results of thirteen years of radiocarbon investigation of large and old African baobab trees

 

 

Activity 2.4.3. The writing of the annual activity report. This activity refers to the writing of the present report.

 

Conclusions

The information presented above proves that the objectives mentioned in the unique phase of the Project Implementation Plan for 2018 have been fulfilled. Additionally, all envisaged results have been obtained.

 

                                                                                                            Project manager,

Prof. Dr. Adrian Pătruţ

 

RAPORT ŞTIINŢIFIC

2019

SCIENTIFIC REPORT

on the implementation of the project entitled


Age, growth and architecture of monumental angiosperm trees assessed by AMS radiocarbon investigation and climate research performed by stable isotope analysis of

wood samples collected from such trees


Code PN-III-P4-ID-PCE-2016-4-0776

Grant No. 90/2017

________________________________

for the period January - December 2019



The scientific activities of the research project pursued the fulfillment of the objectives mentioned in the unique phase of the Project Implementation Plan for 2019.

Unique phase 3 (2019): The investigation of superlative trees by AMS radiocarbon dating and stable isotope analyses (III).

Objective 3.1. Dating baobabs (III).

Activity 3.1.1. Sample collection from 12 baobabs. A number of 30 representative Grandidier baobabs (Adansonia grandidieri) from Madagascar and 10 African baobabs (Adansonia digitata) from Senegal were measured and investigated. Wood samples were collected from 21 specimens (as compared to 12 specimens envisaged). In 2019, the research team visited twice the area with the most monumental baobabs in the world. These largest A. grandidieri are located in the Morombe area, especially in the so-called Andombiry Forest, which is bounded by four villages: Belitsaka, Andombiry, Ankoabe and Isosa. The two field trips took place in the time frame 09-21 April 2019 and 03-15 August 2019. Two members of the research team paid a visit to Senegal during 01-12 November 2019, in the area Dakar-M’Bour-Fissel. The last field trip of the year was scheduled between 08-17 December 2019 to attend a conference in the famous Morondava area of Madagascar.

During the field trips to Madagascar, the renown sacred baobab Tsitakakoike (in Masikoro “the tree where one cannot hear the cry from the other side”) of the Andombiry village was revisited. The tree partially collapsed on the nights of 15 and 16 January 2018 due to cyclone AVA, which hit the region at a wind speed of almost 200 km/h. Increased rainfall and major flooding episodes in January 2019, led to further toppling of branches and stem parts. Thus, a better sample collection directly from the false cavity walls of the dying baobab was facilitated (Figure 1). The investigation of these new samples evinced even older age radiocarbon dates and calibrated calendar ages for this specimen.

Figure 1. Photo of the huge dying baobab Tsitakakoike (April 2019).



The new Tsitakakoike in the Ankoabe village, which was visited and measured in October 2018, is now called Tsitakakantsa (in Masikoro “the tree where one cannot hear the song form the other side”) (Figure 2). After the heavy rainfall recorded in January, its swollen trunk reached a cbh = 28.90 m (circumference at breast height, i.e., at 1.30 m above ground level ). The height measures h = 15.4 m and the baobab has a closed ring-shaped structure with 6 main stems and several smaller ones.

Figure 2. Tsitakakantsa is the baobab with the largest circumference in Madagascar (28.90 m).



Another millenial specimen in the Andombiry area was identified and named baobab “A-257”. It has a false cavity inside, with an inaccesible small opening at a height of 0.81 m. The thickness of the cavity walls is Δ = 1.16-1.45 m. The baobab has a height of h = 17.8 m, a cbh = 25.70 m and possesses a closed ring-shaped structure defined by 5 perfectly fused stems (Figure 3).

Figure 3. Baobab A-257 has the third largest circumference in Madagascar (25.70 m).


Another spectacular monumental baobab, similar to the Pregnant baobab, was discovered in the Andombiry area and named “Baobab oeuf” (Egg baobab). The tree exhibits a closed ring-shaped structure, probably composed of 5 stems. Our investigations provided the following measurements: h = 17.5 m, cbh = 25.02 m. The primary branches have a diameter of 2-2.5 m.

Figure 4. The Egg baobab ranks 5th in the Andombiry forest, with a circumference of 25.02 m.


Senegal is the country with the highest number of African baobabs (Adansonia digitata) in the world, concentrated in impressive forests and natural reserves/protected areas (Nguekokh, Bandia, Samba Dia). Our research team also paid a visit to two baobabs with the largest circumference in the Northern Hemisphere, namely the baobabs of Warang and Lalam. Thus, the Ngokole baobab (meaning “small pods/fruits” in Seser) of Lalam, located close to Fissel, consists of a ring shaped structure with no less than 13 fused stems, out of which 6 are false ones (Figure 5). The measurements are h = 28.5 m, cbh = 28.22 m. This specimen is not only one of the largest baobabs of Senegal (ranked 2nd by circumference), but also one of the tallest.

Figure 5. The Ngokole baobab of Lalam has 13 stems, a height of 28.5 m and a cbh of 28.22 m.


The largest baobab of Senegal and the Northern Hemisphere is a specimen located in Warang, close to M’Bour. This baobab also exhibits a closed ring-shaped structure consisting of 3 main stems disposed around a false cavity, 3 older stems, 6 younger stems and 6 false stems (Figure 6). Consequently, the baobab of Warang has the highest number of stems in the world, namely 18. The following measurements were registered: h = 23.1 m, cbh = 28.69 m.

Figure 6. The majestic baobab of Warang has 18 stems and the largest circumference in the Northern Hemisphere (28.69 m). The photo was taken in 2011.


Unfortunately, the state of the monumental baobab of Warang manifests a continuous decline since our first visit in 2011. In 2015, after becoming private property, the construction of a house in the area adjacent to the tree was implemented, which led to the damaging of roots and subsequently, the drying of some branches. In 2019, the tree is no longer accessible, being enclosed by a yard with tall fence walls. Once again, we reached out to the Senegalese authorities to warn and present the issue, requesting further protection measurements to ensure the survival of the specimen.


Activity 3.1.2. Pretreatment of samples (61-76 segments), 3.1.3. Radiocarbon dating by AMS (61-76 segments) and 3.1.4. Calibration (61-76 segments). The 3 activities are associated, because the first one precedes and the last one is subsequent to radiocarbon dating. During our field trips, samples from 21 baobabs were collected (compared to 12 envisaged). The number of pretreated, dated and calibrated segments obtained from the samples was 105 (as compared to 61-76 envisaged).

The radiocarbon dating by AMS (accelerator mass spectrometer) was performed at the iThemba Laboratory for Accelerator Based Sciences (iThemba LABS) in Johannesburg (South Africa).


Objective 3.2. Climate study (III) with possible field trips to South Africa, Namibia, Mozambique, Angola, Zimbabwe, Botswana and Madagascar (for 1-3 persons)

Activity 3.2.1. Collecting samples from 4 baobabs, 2 Vachellia erioloba and 1 oak; 3.2.2. Pretreatment (7000 segments); 3.2.3. Stable isotope analysis (7000 segments). For the climate study, samples from 8 Grandidier baobabs from Madagascar were collected (compared to 4 envisaged), 2 Vachellia erioloba samples (compared to 2 envisaged) and 1 oak from Romania (compared to 1 envisaged). A number of 8800 wood samples were pretreated by using the acid-base-acid method or the modified α-celullose extraction procedurre/method (as compared to 7000 envisaged). Following the pretreatment, the 8800 samples were subsequently investigated by stable isotope analysis (as compared to 7000 envisaged) by IRMS (isotope ratio mass spectrometer) Delta V Plus. The remaining samples will be analysed in the near future. The stable isotope analysis was performed at the University of Pretoria (South Africa).

Objective 3.3. Measuring and dating trees of Romania and Europe (III + finalising part II) with possible field trips in Romania (Bucureşti, Mocod, Merchiaşa, Oradea, Cajvana, Sighişoara, Iaşi, Rafaila, Merchiaşa, Botoşana, Aiton, Ţebea, Blaj, Arad, Simeria) and Europe (Moldavia, Hungary, Germany, Italy, Turkey, Georgia, France, Spain, Portugal, Denmark, Austria) (for 1-4 persons).

Activity 3.3.1. Complete measurements of 50 trees and 3.3.2. Collecting samples from 4 trees. Complete measurements of 65 trees were performed (as compared to 50 envisaged) from Romania, Hungary, Austria and Germany. The investigated tree species were the following: pedunculate oak (Quercus robur), sessile oak (Quercus robur), ash (Fraxinus excelsior), black poplar (Populus nigra), white poplar (Populus alba), Oriental plane (Platanus orientalis), and European beech (Fagus sylvatica). Samples from 5 trees were collected (as compared to 4 envisaged).


Activity 3.3.3. Pretreatment (20-30 segments), 3.3.4. Radiocarbon dating (20-30 segments), 3.3.5.Calibration (20-30 segments). A number of 40 segments were pretreated by the acid-base-acid method (compared to 20-30 envisaged). The radiocarbon dating was performed at the iThemba Laboratory for Accelerator Based Sciences (iThemba LABS) in Johannesburg (South Africa). The radiocarbon dating results were calibrated for obtaining calendar ages.

Objective 3.4. Dissemination of results.


Activity 3.4.1. The writing of 3-5 scientific articles and submitting or publishing them in ISI journals.

In 2019, we published a number of 4 scientific papers (compared to 3-5 envisaged). Another paper shall be submitted by the end of 2019, while two further articles will be submitted in the time frame January-February 2020. All articles mention that this research was supported by the Romanian Ministry of Research and Innovation CNCS-UEFISCDI under grant PN-III-P4-ID-PCE-2016-0776, No. 90/2017”.

The 4 papers published in 2019 are the following:

1. A. Pătruţ, R.T. Pătruţ, L. Rakosy, D.A. Lowy, D. Mărgineanu, K.F. von Reden, Radiocarbon investigation of the superlative African baobabs from Savé Valley Conservancy, Zimbabwe, Studia UBB Chemia, 2019, LXIV, 2 (Tom II), 7-14. doi: 10.24193/subbchem.2019.2.35.

2. A. Pătruţ, S. Woodborne, R.T. Pătruţ, G. Hall, L. Rakosy, C. Winterbach, K.F. von Reden, Age, growth and death of a national icon: the historic Chapman baobab of Botswana, Forests, 2019. 10, (11), 983. doi: 10.3390/f10110983.

3. A. Pătruţ, A. Garg, S. Woodborne, R.T. Pătruţ, L. Rakosy, I.A. Raţiu, D.A. Lowy, Radiocarbon dating of two old sacred baobabs from India, PLOS One, 2019. doi: 10.1371/journal.pone.0227352.

4. R.T. Pătruţ, A. Pătruţ, J.M. Leong Pock-Tsy, S. Woodborne, L. Rakosy, P. Danthu, I.A. Ratiu, J. Bodis, K. von Reden, Radiocarbon investigation of a superlative Grandidier baobab, the Big Reniala of Isosa, Studia UBB Chemia, 2019, LXIV, 4, 131-139. doi: 10.24193/subbchem.2019.4.10.


A fifth article, which shall be submitted by the end of 2019, will probably get published in early 2020:

5. R.T. Pătruţ, A. Pătruţ, L. Rakosy, D.A. Lowy, J. Bodis, K.F. von Reden, Radiocarbon investigation of the historic Big tree at Victoria Falls, Zimbabwe, Studia UBB Chemia.


A further article entitled “Radiocarbon investigation of monumental African baobabs from Senegal” (Authors: Adrian Pătruţ, Roxana T. Pătruţ, Oumar Ka, Sebastien Garnaud, Tomas Diagne, Karl von Reden) will be submitted in early 2020.


A very important paper, which would contribute to the conservation of A. grandidieri shall be written and submitted to an international journal in early 2020. The article is entitled “Investigation of superlative Grandidier baobabs from the Giant Forest of Andombiry” (Authors: Adrian Pătruţ, Roxana T. Pătruţ, Laszlo Rakosy, Stephan Woodborne, Pascal Danthu, Jean-Michel Leong Pock Tsy, Daniel Lowy, Karl F. von Reden).


The project manager, Adrian Patrut, was invited as a keynote speaker to the “1st International Congress on Baobabs” (original title in French “Congrès sur les baobabs”) in Morondava during 11-13.12.2019. Unfortunately, due to the landfall of cyclone Belna, the conference was postponed last minute and took place on the 15-17.12.2019. Both the project manager and the research assistant Roxana Patrut prepared and delivered a presentation in French.


Activity 3.4.3. The writing of the final activity report. This activity refers to the writing of the present report and the final compilation of all reports.


Last but not least, the preliminary evaluation in October 2019, mentioned a further aspect, which was not envisaged among the objectives nor the activities of the current research project:

The extent to which the project contributes to the development of the human resource for research.

Accordingly, it will be mentioned that among the members of our research team there are currently a PhD student, Roxana Patrut and a postdoctoral scholar, Dr. Ileana-Andreea Ratiu. The PhD student participated in many national/international field trips and is a co-author of 9 scientific papers and 6 presentations at international conferences. In two notable cases, the PhD student is the first and also the corresponding author. The PhD student has prepared the dissertation entitled “The investigation of superlative trees by radiocarbon dating for determining the age, architecture and growth rates and by stable isotope analysis for climate study” entirely based on the research which was undertaken on the current project. The thesis will be finalised and defended in the first 6 months of 2020. The original title of the thesis in Romanian is: “Investigarea unor arbori superlativi prin datare cu radiocarbon prin AMS în vederea determinării vîrstei, arhitecturii și vitezelor de creștere, respectiv prin analiză de izotopi stabili în vederea studiului climatic”


The postdoctoral scholar also partook in various national/international field trips and she is a co-author of 4 scientific papers and 1 presentation at international conferences.


A student at the Faculty of Chemistry and Chemical Engineering, namely Liliana Ioana Cordis, presented her Bachelor´s thesis “AMS radiocarbon dating of large indigenous and tropical trees” (original title in Romanian: “Datarea cu radiocarbon prin spectrometrie de masă cu accelerator a unor arbori angiospermi indigeni si tropicali”), academic tutor: Prof. dr. Adrian Pătruţ, based on the results and investigation of the current research project.


Conclusions

The information presented above proves that the objectives mentioned in the unique phase of the Project Implementation Plan for 2019 were fulfilled. Additionally, all envisaged results were obtained.



Project manager,
Prof. Dr. Adrian Pătruţ


Design and implementation by contact@andreicociuba.ro