Volcanic, climatic and human ecosystem modification

My second pair articles from Vegetation History & Archaeobotany that I would like to highlight look at the impacts of volcanoes and climate on vegetation change. Specifically these explore:

For more detailed thoughts on these papers read on…

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Vegetation History & Archaeobotany

vhaI am delighted to report that I have recently been appointed as an Associate Editor for the journal Vegetation History & Archaeobotany (VHA). The journals scope is global and covers Quaternary environmental and climatic change, with a specific focus on the Holocene and pre-historic human impacts on landscapes; often linking palaeoecological and archaeological research. My remit with VHA is to provide expertise on tropical, and in particular South American, studies. Recent articles in VHA with a South American focus include:

I hope that over the next few years we can publish some more exciting articles on the tropics in VHA and I would therefore like to encourage you to submit interesting high quality original research, reviews, or short articles for our consideration.

To find out more about the journal and submit an article click here.

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Shining a light on fossil sunshine

Dr. Phil Jardine

Dr. Phil Jardine

An international team of scientists have reconstructed the longest ever record of past sunshine using pollen trapped in lake sediments collected in Ghana, Africa. The study published today in Scientific Reports enables us to understand past changes in solar input to the global system over the past 140,000 years. Previously we have had to rely upon computer models to mathematically determine past solar inputs to the Earth. “This work really is a first; being able to peer back in time to understand how the Sun has driven our global system over many of thousands of years is a very exciting prospect” said joint-lead author Dr. Phillip Jardine of The Open University.

The Sun is a key component of our natural environment, driving a multitude of processes at Earth’s surface, from photosynthesis generating energy within plants, through to global-scale circulation patterns in our oceans and atmosphere. Understanding more about how the Sun has behaved in the past, and the influence this had on Earth’s environment, will help scientists predict future climate change.

Dr. Jardine used a technique pioneered by one of his co-authors, Dr. Wesley Fraser of Oxford Brookes University, to determine past changes in solar input, specifically changes in ultraviolet (UV) radiation. Plants protect themselves from the harmful nature of ultraviolet radiation by incorporating a number of specific chemical compounds into their tissues that absorb and dissipate the energy of UV radiation. Pollen grains of flowering plants are also provided protection by these UV-absorbing chemicals, thus act as a long-term recorder of ultraviolet radiation from the Sun.

Pollen grains are readily trapped in lake sediments, where they can be preserved for millions of years. By extracting material from Lake Bosumtwi, Ghana, the pollen that was released by flowering plants thousands of years ago can be separated from the lake sediment and chemically analysed for UV-absorbing chemical compounds. It is this chemical signature within the ancient pollen grains that provides us with information about past levels of solar ultraviolet radiation.

“What we present here is a new opportunity to explore how the Earth has changed” said Dr. William Gosling (University of Amsterdam). “I am particularly excited about this because it will means that we can gain a better understanding of why vegetation changed in the past, and consequently this will allow us to anticipate better what the likely impacts of projected future climate change will be.”

This study is available now at www.nature.com/articles/srep39269

Jardine PE, Fraser WT, Lomax BH, Sephton MA, Shanahan TM, Miller CS & Gosling WD (2016) Pollen and spores as biological recorders of past ultraviolet irradiance. Scientific Reports. DOI: 10.1038/srep39269

Job: Palaeoecology at VU Amsterdam

VU Amsterdam

The Vrije Universiteit (VU) Amsterdam currently has a vacancy for an Assistant Professor in Palaeoecology. The VU Amsterdam are looking for a specialist in palaeoecology, palynology and/or palaeobotany, with an interest in reconstructing climatic- and anthropogenic forcing of vegetation/landscape/hydrological change in the Quaternary. Experts employing palynological, macro-fossil, geochemical, and modelling techniques welcome.

The VU Amsterdam group have strong links with the Institute for Biodiversity & Ecosystem Dynamics (University of Amsterdam), including my Palaeoecology & Landscape Ecology group.

Deadline: 08 December 2016
Further details click here.

Scientific methods in archaeology

Preparing my lecture for the new Scientific Methods in Archaeology course for VU Amsterdam and University of Amsterdam students studying a minor in Geoarchaeology. The focus will be on detecting human activity in the past, to illustrate this I will include Easter Island/Rapa Nui as a case study. We will focus on how palaeoecological evidence can be used to gain insights into past human activity. Whilst putting this together I discovered these nice documentaries looking at humans and their environmental impacts on Easter Island/Rapa Nui which I wanted to share, they show how much effort people would have had to put into altering their landscape:

For further information see also:

Rull, V., Cañellas-Boltà, N., Saez, A., Margalef, O., Bao, R., Pla-Rabes, S., Valero-Garcés, B. & Giralt, S. (2013) Challenging Easter Island’s collapse: The need for interdisciplinary synergies. Frontiers in Ecology and Evolution 1, DOI: 10.3389/fevo.2013.00003