BES 2017: El hábito de documentar el mundo natural

Antes de comenzar mi doctorado nunca había visitado España. No tenía cómo imaginar cuáles eran las consecuencias de ser una colonia española.

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British Ecological Society – Emerging Plant Pests and Pathogens Symposium 2015

Last week I had the opportunity to present the preliminary results of my graduate research at the Emerging Plants and Pathogens Symposium supported by the British Ecological Society. It has held at the University of Exeter, Penryn campus in Cornwall, UK between 13 – 14 July 2015. Organised by Dan Bebber and Professor Sarah Gurr, the purpose of the event was to bring together experts from different fields to discuss the implications of emerging plant pests and pathogens in global food security and ecosystem resilience.

In this short post, I share a few pictures and my impressions of the symposium.


The first step to present a poster, is to make the poster. The final result was a shared effort, of course, with the indispensable contribution of my supervisors Dan Bebber and Sarah Gurr. I was able to share this preliminary research at #pestsym – thanks to my donors Gerry & Clemencia Posada-Brown who have funded my MSc Food Security and Sustainable Agriculture at the University of Exeter.

Day 1

Dan Bebber gave the symposium a very brief welcome quickly followed by a presentation by Professor Charles Godfray, from the University of Oxford, aimed at explaining the current challenges of global food security, the perspective through which we were to understand the research discussed over the next two days.


Charles Godfrey (University of Oxford) – Challenges for our Global Food Security

My favourite talk of the day was in the theme novel detection methods. Anne-Katrin Mahlein from the University of Bonn – spoke about the technologies being developed to detect plant diseases using mobile phones. Since I’m Colombian, I think about what are the implications for Colombian agriculture. Well, the possibilities are overwhelming, particularly for smallholders in remote areas that have very little except a mobile device. Personally, it was very exciting to see the application of research with the talk on detection of diseases through mobile image sensing. Business-led implementations perhaps are more quick and effective than government policy – that’s why this was my favourite presentation of the day.

I’d like to mention that we had ‘proper’ cream tea more than once during the event. ‘Proper’ cream tea entails clotted cream tea and strawberry jam with tea and milk. Since we were in Cornwall, we had local clotted cream which probably was the reason for serving it during our breaks – delicious!


‘Proper’ cream tea: generous amounts of strawberry jam are smeared atop local Cornish clotted cream over the transversal cut of a scone.

The lectures ended with a debate chaired by Melanie Tuffen from the Department for Environment, Food & Rural Affairs (DEFRA) who was also my neighbour during the poster presentations. The question discussed was: is plant biosecurity research addressing the needs of policy? The implications for global trade are significant since the stuff we buy and our travels are vectors for disease.

It was very cool to witness researchers and civil servants (Nicola Spence also from DEFRA), openly argue on the challenges of biosecurity and what needs to be done. There was certainly a tension between global trade and increasing biosecurity barriers and engaging more young people in public policy was mentioned.


Melanie Tuffen from DEFRA moderating the debate: Is plant biosecurity research addressing the needs of policy?

The day ended with the poster presentation session accompanied by Cornish cider. It was great fun to have a one-to-one talk with other researchers attending the event. I would like to thank the many people who gave their helpful feedback for our coffee leaf rust research including Michael Shaw from the University of Reading, Julie Flood from CABI and Jean Beagle Ristaino from North Carolina State University.


Poster presentation and Cornish cider. UK science events are fun!

Day 2

The Penryn campus was very green and uncrowded so I decided to go on an early morning 5k run before the start of the talks.


The Cornwall roads near the Penryn campus during summer.

My favourite talk of this day was by my supervisor Professor Sarah Gurr, Chair of Food Security at the University of Exeter. She shared the important work she has been involved with in recent years presented sort of like a timeline where findings were integrated into one narrative and implications presented as predictions for global food security.


Profesor Sarah Gurr – Chair of Food Security at the University of Exeter

Her talk was the last of the day but managed to be very clear and concise sustaining everyone’s attention. It was followed by the final remarks, a question and answer session with Dan Bebber.


Dan Bebber and Sarah Gurr during the closing remarks

After the day was formally over, some of us went out for dinner in Falmouth. Here are a few pictures of the evening. Overall, it was a very intense learning experience and it’s cool to meet and interact with other researchers in different countries working on similar things.


Group picture in Falmouth


The sweet view from our restaurant


Delicious dinner


How does climate change affect food security? – Production

Read this very, very, short introduction first (not boring I promise but super important).
Imagine you’re a maize farmer from Iowa or Illinois. On any given day, would you think about how your actions have a critical effect on the livelihood of millions of people in developing countries? Yeah, me neither. That’s why when I read this article, the foundation for this post, I couldn’t believe how many people depend on maize yields produced in the U.S. and what happens when maize is not delivered.
At some point in your life you’ve probably seen a plant wilt and die from either lack of water or too much of it. Climate change is expected to increase the frequency of extreme weather events, that includes both those things: too much water (floods) or too little (drought). Since 96% of our food is directly or indirectly derived from soil, drought and floods mean trouble for food production.
How does climate change affect food security? – Production
(Read introduction to series here)
Case: Drought in the U.S. ‘corn belt’ – 2012

a) Extreme weather event
March to April (2012), was classified as the warmest and seventh driest maize growing season in the U.S. ‘Primary Corn Belt – a region prominently dedicated to the intensive cultivation of this crop. According to NOAA, this dry and warm combination led to declaring 89.3% of this agricultural region as suffering from moderate to severe drought (little rain and high temperatures) in September 2012.
b) Direct and indirect consequences (Gbegbelegbe, Chung, Shiferaw, Msangi, & Tesfaye, 2014)
The 2012 drought in the U.S. agricultural maize region led to a reduction of maize yields of 97 million metric tons (m.m.t.)

The U.S. is the world’s largest supplier of maize exports responsible for 72% of global exports, however, these yields typically correspond to surplus. What does surplus mean? It means the U.S. satisfies their own demand for maize first and then sells what is left to the rest of the world. The drought barely affected U.S. internal maize consumption since most of the production stayed in the country, the 2012 losses meant a 5% reduction from what the U.S. usually uses.In numbers, the usual (trend) production compared with the actual one because of the drought. We’re not saying that the 2012 drought meant nothing for the U.S., it did, but the ripple effects for the rest of the world that depends on these maize exports were very powerful.77.8 m.m.t. less U.S. maize exports for the rest of the world in 2012 Here comes the critical question: who was expecting those 77.8 million metric tons of U.S. missing maize? Where were they suppose to go and what happened when they didn’t arrive?
(Spoiler: developing countries and millions of people at risk of hunger)
c) Impact on food security (Gbegbelegbe, Chung, Shiferaw, Msangi, & Tesfaye, 2014)
The consequences of this maize scarcity were surprising to me because they reached millions of people in places far from the U.S. Corn Belt region. East and South East Asia suffered the largest decrease in volume (19 m.m.t.). But! the largest relative decrease (this means compared to the levels without the drought) was in Sub Saharan Africa by 9% (4.8 m.m.t.) – uh oh.
If you remember, the U.S. was affected by 5%, only 0.3% of that was meant to go to food, the rest would have gone to animal feed or other uses. In contrast, 10% of the missing 4.8. million metric tons of maize in Africa, were for food. In Latin America and the Caribbean, there was also a pretty significant relative reduction of food: 7% which represents 1.8 m.m.t.
When these percentages are applied to the populations from these regions, we’re talking about millions of people at risk of hunger because of an extreme weather event associated to climate change.This graph shows the food security consequences of the 2012 U.S. drought that led to reduced global maize exports. Click on the graph to access the source. SSA – Sub-Saharan Africa; LAC – Latin American and Caribbean;  EA & SE Asia – East & South East Asia; ROW – Rest of the world; CWANA – Central and West Asia and North Africa So, how does climate change affect food security? Well, in this case we saw that an extreme weather event (drought) in a region that produces 72% of global maize exports leads to missing yields that put 17 million people in Sub-Saharan Africa at risk of hunger and 2.6 million people in the Latin America and Caribbean region.
d)  Lessons learned
There are two important factors that contribute to how many people become at risk of hunger in the face of agricultural scarcity that we can take from this case:
1. The number of people that depend on the affected crop and to what extent. In this case, how many people eat maize and how much of their daily caloric intake comes from this plant.
2. The capacity to substitute the missing calories. In this example, how easy or hard was it to access other foods like cassava, wheat and rice, in the context of maize scarcity.
The risk associated to these factors can be reduced in part by diversifying calorie sources: different foods from different places.  By depending on more than one producer, Brasil and Argentina also export large volumes of maize, risk can me mitigated. By getting calories from other types of crops: barley, wheat, cassava, rice, quinoa, the likelihood of having millions of people at risk of hunger because of one single incident, can also be lowered.
This post was based on this great paper that I’ve been able to talk about freely because it’s under a Creative Commons Attribution License! Woot!
I’d like to know what foods do you eat to get most of your calories?  Feel free to comment in the section below.

Read more from the series:

How does climate change affect food security?:How does climate change affect food security? – Challenge accepted

How does climate change affect food security? – Food processing

How does food security happen? Alternative title: deconstructing a bowl of porridge

How does climate change affect food security? – Challenge accepted

Usually, when I tell people what I study, I get asked: how does climate change affect food security? Some may expect this: “climate change is increasing food insecurity.” But that’s an irresponsible statement. Food security is the product of many factors, it can’t be summarised into one sentence.
Still, what if the average person wants to find out the impact of climate change on food security? They do have to deal with both climate and food on a day-to-day basis, the curious non-specialist demands an answer and I’m on a mission. How does food security affect climate change? To provide an answer in layman’s terms: challenge accepted.
There’s also an element of predicting future events. Just to be clear: no one and nothing can predict the future with 100% confidence. The future is the future and it remains uncertain. What we do have, however, is the past. Whatever you may have heard about climate change and its future impacts comes from past information used as a guide to project the future.
How does climate change affect food security? is a four-part series that explains how extreme weather events associated to climate change or climate change consequences (i.e. precipitation variability or increased average global temperature), affect each stage in food systems: production, procession, distribution or consumption.
Where is the food security part? Since food security is an outcome of food systems, this series is actually a close look at each of the steps that contribute to food security. In each post we’ll learn with the help of an example or case divided into 4 parts: a) extreme weather event; b) direct and indirect consequences; c) impact on food security; and d) lessons learned.
Is there any specific climate change/food security relationship you would like me to research and write about? Feel free to comment in the section below.
Read more from the series:

How does climate change affect food security? – Food production

How does climate change affect food security? – Food processing




Climate over time

I convinced my not-so-humble friend, Julien, to sign up for the MOOC and last week he kept saying, “who actually takes this course? I learned all of this in high school!” Well, I ran into him on Monday morning and he confessed that he had attempted the quiz without going through the material and to no one’s surprise he didn’t do so well.

“Things got challenging!” he said. You don’t say.

But that’s what’s exciting about this week. How can two ten-minute videos condense so many theories and tools scientists use to develop an evidence-based timeline of the Earth’s past climate? My learning process for this week was definitely not linear so stay with me and we’ll try to untangle a couple of important questions together.

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A very unscientific explanation of how shells are formed

Ever since I’ve started working for this MOOC, I can’t help but see it everywhere. Walking around the Tate Britain this past weekend I came across these six shelfs of shells – carbon cycle anyone?

In between some funny letters and a video of a man without pants, Damien Hirst – Forms Without Life (1991) at the Tate Britain. Last week’s reflection finished with this question: How do certain organisms form shells by grabbing carbon from the ocean and layering it onto their backs?
This curiosity comes from previous weeks when it was mentioned that certain organisms make skeletons and shells that they use during their lives and when they die *sad face*, these structures sink to the deep ocean floor and with time and pressure become part of what today we buurrrrrn relentlessly: fossil fuels.
Well, the process by which organisms form minerals is called biomineralization. If you are familiar with the specialised language of this discipline, then go ahead and read this paper and skip to the last bit of this post (Questions for upcoming weeks and other stuff),  if you’re not and you want to get a brief overview, here is my digest about how this magical (biochemical) process works.
There are two types of biomineralization processes:
• Biologically induced: comes from the interaction of biological activity and the environment.
• Biologically controlled: the organism controls the creation of the biomineral.

Shells correspond to the second type of biomineralization, as do our teeth and bones. We make biominerals too!
This type of biominerals are characterized for having complex morphologies, controlled aggregation and texture, preferential crystallographic orientation, well defined structures and compositions and high levels of spacial organisation. I think we can tell all this from just looking at them, dreamy and full of math.

Biominerals are made from, well, both mineral and organic components. 50% of biominerals contain calcium with calcium carbonate as the most abundant compound. Carbon dioxide near seawater breaks down into carbon and sea organisms like molluscs and fish turn some of it into calcium carbonate (CaCO3).
How do shells grow? An answer by a non-artist & non-conchologist:
Shells contain 2% protein and the rest of the material precipitated (or layered) is a mix of different biominerals, I came across this very useful metaphor to understand the role of protein in building shells: the steel and concrete analogy. Protein works as steel forming the matrix and the mineral acts as the concrete that will be poured onto this matrix. Shells have 3 layers, the top layer is called periostracum and is made from a protein called conchiolin. The layer closest to the mantle is also known as nacre, the iridescent substance made from crystal aragonite platelets which disperse light and make it so beautiful. Mantle tissue inside the shell secretes the mineral and protein from the inside out – the oldest layer is on the outermost part of the shell and youngest layer is closest to the mantle tissue. Questions for upcoming weeks and other stuff
So, some questions have been answered. However, calcium carbonate is alkaline (pH 9.91) and since carbon dioxide is absorbed by seawater lowering carbonate ion concentration, a.k.a. ocean acidification, what’s the relationship between this and all the living systems in the ocean that produce and use calcium carbonate?
Week 5 I look forward to you.
In the mean time, let me finish this post by saying that I share the same sentiment as fellow blogger Penny Insole who said that she didn’t find this week’s content as challenging as week 2. Me too! Everything was pretty straightforward, except the bit about how Antarctica loses mass and how its ice melts.
I’d like to add that I found some of the resources useful because my dissertation (still cold as Snowball Earth) involves climate change and trying to link it to the recent coffee rust outbreak in the American continent, particularly in Colombia. Coffee rust is a fungus that needs free moisture to germinate and guess what I found on the extreme events tool? Well, well, well, if it isn’t an extreme rain and flood event in 2011 in Colombia related to La Niña. Heavy rainfall and floods related to La Niña in 2011 – this is an awesome clue. Anyway, statistics will tell if there is a true relationship between this extreme rainfall event and the devastating coffee rust outbreak. I’ll definitely talk more about my dissertation in September when it’s done.
If you enjoy climate tools like this, why not check out the great climate analogues tool.
See you next week and I’m always happy to read your blogs too so please link to them in the comment section below. Josh, another MOOC assistant, is blogging to create a glossary of key terms, check out his blog here. Thank you for reading.