Three good news

We are very proud to inform researchers that the Van Thuyne Ridge Research center has signed a partnership with the Botswana International University of Science and Technology (http://www.biust.ac.bw) rendering possible fruitful developments for both entities and creating a wide array of research opportunities. Researchers now from BIUST can come on a weekly base to use the center in the Chobe Enclave. A PhD student from BIUST will start from January 2019 to work from the University of Lausanne on neo-tectonic activities in the Chobe Enclave area.

 

An important Swiss National Fund grant was given to the Institute of Earth Surface Dynamics (IDYST) of the University of Lausanne. This grant will be used to enroll a PhD student working on the sedimentology processes of the Chobe Enclave in the aim of reconstructing paleo-environments and paleo-climates in this region. It will also be used for laboratory work taking place at IDYST, BIUST and at the VTR research center as well as for field research in Botswana.

 

Last but not least, after two year of trial and mishaps, our Luft-Sensorscope weather station is now fully operational. It is based at the VTR center and is accessible from all over the world for anyone interested. A great deal of data can be collected, stored and displayed using the efficient and user-friendly platform of Sensorcope. Added to that we now have a dust collector in place during the dry season and a water collector for the rainy season. To access the weather station data:

Go to: https://www.climaps.com

The ID station : 1809

Login: vtrjohn

Password: JVTmeteo

Or go directly to:

https://www.climaps.com/?page=dashboard

Latest area survey

From the latest data collected for the Chobe Enclave, gathered from " Status of Wildlife Populations and Land Degradation in Botswana's Forest Reserves and Chobe District" Michael Chase- Elephants Without Bordres and the San Diego Zoo Institute for Conservation Research.

The Chobe district is situated in the northeast corner of Botswana. It is centered in the heart of the vast Kavango/Zambezi river system. The total size of the district is 22’560 sq.km. 52% of the land is the Chobe National Park, 18% are Forest Reserves, the remaining is the Kasane township, which is the district headquarters, the Chobe Enclave and farmlands to the south. The district is built on basalt rocks; deposits of Kalahari sands cover most of the solid geology. The total human population is 21’800. Estimates of the elephant population are 41’000, cattle 4800, Baobabs 708.

The Chobe Enclave covers an area of 1680 sq.km, approximately 30km from north to south and 60km from east to west. The human population is 4’500, elephants 8’800, cattle 2’000, Baobabs 240. Ethnic groups are Basubiya who are fisherman and cattle herders (70%), Batawana who are farmers and pastoralists (28%) and Xo one of Botswana’s San groups (2%). The land is geographically enclaved by the Linyanti River in the north, by the Chobe River to the east, opened savanna to the west and by elevated hills in the south. (Chobe District Development Plan 6).

 

The University of Lausanne in African territories

Three Professors, of which one is the director of the department of Biology from the University of Lausanne and the other is the director of the department of Biology from the University of Bern came to do some research on bats and termites in northern Botswana. They were joined by three other Doctors in biology doing a preliminary study on the small mammal fauna of the Chobe Enclave and its associated ectoparasites.

Please read below the article that was published in french in the quarterly magazine "Allez Savoir" of the University of Lausanne.

http://wp.unil.ch/allezsavoir/lunil-en-terres-africaines/

New study suggests half of lion populations will be lost in key regions of Africa

A team of scientists from global wild cat conservation organisation Panthera, Oxford University's WildCRU, Grimsö Wildlife Research Station, IUCN Species Survival Commission Cat Specialist Group, and the Department of Ecology, Evolution and Behavior at the University of Minnesota estimated the trajectory of lion populations by compiling and analysing regional population trend data for 47 different lion populations across Africa. The analysis showed that whereas most lion populations in West, Central, and East Africa are declining, increases in lion populations occurred in four southern countries: Botswana, Namibia, South Africa and Zimbabwe.

Lead author Dr Hans Bauer of WildCRU said: 'These findings clearly indicate that the decline of lions can be halted, and indeed reversed as in southern Africa. Unfortunately, lion conservation is not happening at larger scales, leading to a vulnerable status of lions globally. In fact, the declines in many countries are quite severe and have enormous implications.

Dr Luke Hunter, President and Chief Conservation Officer of Panthera and a co-author, said: 'We cannot let progress in southern Africa lead us into complacency. Many lion populations are either gone or expected to disappear within the next few decades. The lion plays a pivotal role as the continent's top carnivore, and the free-fall of Africa's lion populations we are seeing today could inexorably change the landscape of Africa's ecosystems.'

The authors note that conservation efforts in southern Africa are successful for a number of reasons, including low human density, significant resources, and perhaps most importantly, the reintroduction of lions in small, fenced and intensively managed and funded reserves. Dr Paul Funston, Senior Director of Panthera's Lion Program, said: 'If we don't address these declines urgently, and at a massive scale, the intensively managed populations in southern Africa will be a poor substitute for the freely roaming lion populations in the iconic savannahs of East Africa. In our view, that’s not an option.'

 The full paper, 'Lion (Panthera leo) populations are declining rapidly across Africa, except in intensively managed areas', appears in Proceedings of the National Academy of Sciences of the United States of America (PNAS).

One year of existence

We have completed the construction of the Research center a year ago, and we are operational since June 2014. In a year we have received 14 students from different part of the world, 5 professors from Botswana, Belgium, South Africa and the United States, and 7 researchers. Each is working in different field of research, ranging from hydrogeology, geochemistry, sedimentology, vegetation mapping, wildlife migration, fresh water shells sampling, human/wildlife conflicts, environmental monitoring, biodiversity conservation.

We are developing a nice relationship with the Chobe Enclave Conservation Trust. We bought a beautiful aluminium boat with a powerful 4 stroke engine all equipped with the latest environmental standards. The solar system has been independently working for 382 consecutive days, providing us all our electricity needs. We had no technical problems, no accident nor injuries to report. Lions, elephants, leopards, zebras have been spotted around the center. We are regularly welcoming seminars and workshops from the Okavango Research Institute. We have collaborative field work projects with Wildlife Act and the Round River Foundation.

We wanted to thanks those who have help us put together this wonderful toll for science, research and preservation: The Department of Wildlife and National Parks, ORI, the University of Lausanne, Nature Zone and our employees. Thank you for your trust, confidence, professionalism and motivation along this first year.

Aspects of the physical environment: Chobe-Lynianti, Northern Botswana

Une conférence intitulée Aspects of the physical environment : Chobe-Linyanti area, North Botswana sera donnée le 30 septembre à la FGSE par Mme Susan Ringrose, professeure de Géologie et directrice de l’Okavango Research Institute de l’Université de Maun au Botswana.

Cette conférence s’inscrit dans l’idée d’un rapprochement entre les chercheurs de l’UNIL et du VTR Center (Van Thuyne Ridge Center) au Botswana. Mme Ringrose est par ailleurs collaboratrice scientifique du VTR Center, un centre de recherche scientifique pluridisciplinaire cofondé par John Van Thuyne, ancien diplômé d’un Master en Sciences de l’Environnement de l’UNIL et chercheur associé à l’UNIL au sein de l’IGD.

La conférence, donnée en anglais, visera à informer toute personne intéressée (chercheurs, étudiants et grand public confondus) sur les connaissances actuelles de la biologie, de la géologie sur le sol et le substratum du Nord Botswana. Les sujets suivants seront notamment abordés : « East African rift – faulting ; Development of river systems on Kalahari sand ; Calcrete analysis and processes of formation ».

Mme Ringrose sera présente à Lausanne du mardi 30 septembre au jeudi 2 octobre et sera disponible pour des rencontres ou discussions privées.

 

http://www.unil.ch/gse/home/news.html?actunilParam=events&showActu=1410856920759.xml&showFrom=1

 

Fences divide lion conservationists

Traci Watson

Nature 503, 19 November 2013

Some say enclosures offer protection, others maintain they are a menace. Times are grim for the king of the beasts. Roughly 35,000 African lions roam the savannahs, down from more than 100,000 half a century ago, thanks to habitat loss, declining numbers of prey animals and killing by humans. One study estimated that fewer than 50 lions (Panthera leo) live in Nigeria and reported no sign of the animal in the Republic of the Congo, Ghana or Côte d’Ivoire.

Travelling zebras forecast the weather

Nature 500, 24 August 2013 http://dx.doi.org/10.1002/jgrg.20096

Zebras in Botswana heed subtle weather and vegetation clues when choosing when and how to move to greener pastures.

Hattie Bartlam-Brooks of the University of Bristol, UK, and her colleagues fitted adult zebras with tracking collars and monitored them daily on their annual migration from the Okavango Delta to the Makgadikgadi grasslands, around 250 kilometres away. They compared the migrations of seven mares with models informed by satellite data on regional vegetation and rainfall. The animals seemed to use local cues to anticipate the food and water available at their destination and adjust their movements accordingly — for example, by delaying departure or reversing direction when rainfall was unseasonably late.

 

Locomotion dynamics

of hunting in wild cheetahs 

Nature 498,185–189 (13 June 2013)

 

 

 

Although the cheetah is recognised as the fastest land animal, little is known about other aspects of its notable athleticism, particularly when hunting in the wild. Here we describe and use a new tracking collar of our own design, containing a combination of Global Positioning System (GPS) and inertial measurement units, to capture the locomotor dynamics and outcome of 367 predominantly hunting runs of five wild cheetahs in Botswana. A remarkable top speed of 25.9ms−1 (58m.p.h. or 93 kmh−1) was recorded, but most cheetah hunts involved only moderate speeds. We recorded some of the highest measured values for lateral and forward acceleration, deceleration and body-mass-specific power for any terrestrial mammal. To our knowledge, this is the first detailed locomotor information on the hunting dynamics of a large cursorial predator in its natural habitat.

 

First sequences

of Botswana and the project.  

Premières séquences de la région et du projet

For its ten years of existence, the Faculty of Geosciences of the University of Lausanne has selected 10 projects, including the VTR Research Center. Discover John at 07:00.

Pour ses 10 ans, la faculté des Géosciences et de l'environnement de l'Université de Lausanne a mis en valeur une dizaine de projets dont le VTR Research Center. Pour accèder directement, allez à 07:00

Déformation

DU RIFT DE L'OKAVANGO - COUPLAGE AVEC LE CLIMAT ET LES TRANSFERTS DE MATIERE.

Le projet de ce chercheur vise à analyser les couplages entre le fonctionnement sédimentologique récent du delta de l’Okavango, la tectonique extensive et le climat. Il s’agit d’un projet pluridisciplinaire dans le cadre de l’OSUR regroupant tectonicien, géophysicien, sédimentologue et géographe. Ce projet est financé par l’appel d‘offre “Défis émergents 2010” de l’université de Rennes

Ma contribution porte sur la quantification de la déformation actuelle par GPS autour et dans le delta. On attend à la fois une contribution tectonique et hydrologique. Une mission de mise en place du réseau est prévue en octobre. 

Rift deformation in the Okavango Delta 

The project aim is to analyse the coupling between the recent Okavango Delta sedimentology fonctionning, the tectonic expansion and the climat.  It is a pluridisciplinary project in the frame of l'OSUR, grouping tectonicians, geophysicists, sedimentologists et geographs.

 

Geometry and faults

tectonic activity of the Okavango Rift Zone, Botswana:

Evidence from magnetotelluric and electrical resistivity tomography imaging.

a b s t r a c t

We used Magnetotelluric (MT) and Electrical Resistivity Tomography (ERT) to investigate the geometry and nature of faults activity of the Okavango Rift Zone (ORZ) in Botswana, an incipient rift at the southern tip of the Southwestern Branch of the East African Rift System. The ORZ forms a subtle topographic depression filled with Quaternary lacustrine and fluvio-deltaic sediments and is bounded by NE-trending normal faults that are more prominent in the southeastern portion of the rift basin. An MT model from regional (140 km) NW–SE trending MT transect shows that much of the rift basin is underlain by a broad asymmetrical low resistivity anomaly that slopes gently (1) from NW to SE reaching a depth of 300 m. This anomaly suggests that faults in the southeastern part of the rift form a NW-dipping border fault zone and that the lacustrine and fluvio-deltaic sediments contain brackish to saline water filling the broad half-graben structure. Furthermore, MT and ERT models from detailed (4–13 km long) MT transects and resistivity profiles show that one border fault (Thamalakane) and two within-basin faults (Lecha and Tsau) in the southeastern part of the ORZ are characterized by a localized high conductivity anomaly while another border fault (Kunyere) lacks such an anomaly. These localized anomalies are attributed to channelized fresh surface water and saline groundwater percolating through these faults forming ‘‘fault zone conductors’’ and suggest actively displacing faults. The lack of a ‘‘fault zone conductor’’ in the Kunyere fault is interpreted as indicating diminishing displacement on this fault, and that strain was transferred to the Thamalakane fault further to the east. The fluids provide lubricant for the ORZ faults, hence preventing infrequent large magnitude earthquakes, but favoring frequent microseismicity.


Early structural

development of the Okavango rift zone, NW Botswana

 The East African Rift System: Dynamics, Evolution and Environment

a b s t r a c t

Aeromagnetic and gravity data collected across the Okavango rift zone, northwest Botswana are used to map the distribution of faults, provide insights into the two-dimensional shallow subsurface geometry of the rift, and evaluate models for basin formation as well as the role of pre-existing basement fabric on the development of this nascent continental rift. The structural fabric (fold axes and foliation) of the Proterozoic basement terrane is clearly imaged on both gravity and magnetic maps. The strike of rift-related faults (030–050° in the north and 060–070° in the south) parallels fold axes and the prominent foliation directions of the basement rocks. These pre-existing fabrics and structures represent a significant strength anisotropy that controlled the orientation of younger brittle faults within the stress regime present during initiation of this rift. Northwest dipping faults consistently exhibit greater displacements than southeast dipping faults, suggesting a developing half-graben geometry for this rift zone. However, the absence of fully developed half-grabens along this rift zone suggests that the border fault system is not fully developed consistent with the infancy of rifting. Three en-echelon northeast trending depocenters coincide with structural grabens that define the Okavango rift zone. Along the southeastern boundary of the rift, developing border faults define a 50 km wide zone of subsidence within a larger 150 km wide zone of extension forming a rift-in-rift structure. We infer from this observation that the localization of strain resulting from extension is occurring mostly along the southeastern boundary where the border fault system is being initiated, underscoring the important role of border faults in accommodating strain even during this early stage of rift development. We conclude that incipient rift zones may provide critical insights into the development of rift basins during the earliest stages of continental rifting.