Navigation Links
Aznalcóllar disaster compared with Cretaceous mass extinction
Date:2/2/2010

Researchers from the University of Granada (UGR) have compared the disaster caused by the Aznalcllar spillage in the Doana National Park in Andalusia 11 years ago with the biggest species extinction known to date. What do these two disasters have in common? The scientists say that carrying out comparisons of this kind will make it possible to find out how ecosystems recover following mass extinctions.

Until now, scientists used to study the fossil record in order to analyse how organisms responded to major environmental changes in the past, such as the mass extinction of species during the Cretaceous period (65 million years ago) and their subsequent recovery.

Now a team of scientists from the UGR has proposed a different methodology: "Another way of looking at this issue is to compare present day disasters that have also caused an abrupt ecological change, and which have therefore also had a major impact on organisms", Francisco Javier Rodrguez-Tovar, lead author of the study and a researcher at the UGR's Department of Stratigraphy and Palaeontology, tells SINC.

The study, published recently in the journal Geobiology, was based on "one of the worst environmental disasters to have happened in Spain over recent decades".

The pyrite mine at Aznalcllar, in the Doana National Park, burst on 25 April 1988, spilling four million cubic metres of acidic water and one million cubic metres of waste material containing high levels of toxic compounds, which affected more than 4,500 hectares of the rivers Agrio and Guadiamar and the land around them.

The researchers carried out a detailed analysis of how the pollution from Aznalcllar evolved, and how the local plant and animal communities responded following the event, by studying the affected soil. "Comparing this with what happened 65 million years ago could help to better interpret this past event", explains Rodrguez-Tovar.

The similarities are obvious sudden impact, high levels of toxic compounds, and the existence of a polluted layer covering the affected area. However, the scientist also points out some of the most significant differences, such as recovery following the impact, which was "much faster after the disaster at Aznalcllar", and in terms of the area affected, which was "global for the Cretaceous-Tertiary boundary event", says Rodrguez-Tovar.

In search of signs of life

The scientists were able to carry out a range of experiments on the layers of mud that have not been removed from Doana. Geochemical analysis showed that "there is still significant contamination, with high concentrations of toxic elements, and high acidity levels", stresses the palaeontologist. However, less than 10 years after the disaster, the scientists could identify trails and nests made by Tapinoma nigrrima, an aggressive and opportunistic species of ant. "We even found this ant's larvae just below the layer of highly-contaminated mud", explains the expert.

This ant's opportunism, aggressiveness and high levels of independence were compared with the organism that created Chondrites, a trace fossil that scientists have recorded near the red layer associated with the Chixulub crater in Mexico, generated by the impact of the meteorite that caused the Cretaceous-Tertiary extinction. Previous ichnological studies (on trace fossils) have shown that "the Chondrites-generating organism was able to inhabit the substrate immediately after the event, due to its opportunistic and independent nature", says Rodrguez-Tovar.

Using the data on trace fossils and on comparisons with present day disasters, the scientists were able to prove that "the community started to recover fairly rapidly following the mass extinction caused by the impact 65 million years ago, possibly within hundreds or thousands of years", concludes the palaeontologist.


'/>"/>

Contact: SINC
info@plataformasinc.es
34-914-251-820
FECYT - Spanish Foundation for Science and Technology
Source:Eurekalert  

Related biology news :

1. Sensing disasters from space
2. Bioterrorism and disaster preparedness explored in special issue of Medical Decision Making
3. Defying the disaster: Researcher explores resilient housing
4. Pollution at home lurks unrecognized, instead attributed to large-scale environmental disasters
5. International Council for Science launches major research program on natural disasters
6. Looming tropical disaster needs urgent action
7. Killer fungus spells disaster for wheat
8. Triage study challenges notions of emergency medical response to disaster
9. Soil, conservation experts to reflect on Hurricane Katrina disaster
10. Researchers find evidence linking stress caused by the Sept. 11 disaster with low birth weights
11. ORNL resilience plan to help Tennessee, Mississippi and South Carolina communities beat disaster
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Aznalcóllar disaster compared with Cretaceous mass extinction
(Date:4/5/2017)... KEY FINDINGS The global market ... CAGR of 25.76% during the forecast period of 2017-2025. ... for the growth of the stem cell market. ... MARKET INSIGHTS The global stem cell market is segmented ... The stem cell market of the product is segmented ...
(Date:3/30/2017)... Trends, opportunities and forecast in this market ... (fingerprint, AFIS, iris recognition, facial recognition, hand geometry, vein ... use industry (government and law enforcement, commercial and retail, ... others), and by region ( North America ... Pacific , and the Rest of the World) ...
(Date:3/24/2017)... 2017 Research and Markets has announced the ... & Trends - Industry Forecast to 2025" report to their ... The Global ... CAGR of around 15.1% over the next decade to reach approximately ... the market estimates and forecasts for all the given segments on ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... (PRWEB) , ... October 11, 2017 , ... ... Foundation President Andi Purple announced Dr. Suneel I. Sheikh, the co-founder, CEO ... ASTER Labs ), Inc. has been selected for membership in ARCS Alumni ...
(Date:10/11/2017)... (PRWEB) , ... October 11, 2017 , ... ... pathology, announced today it will be hosting a Webinar titled, “Pathology is going ... Pathology Associates , on digital pathology adoption best practices and how Proscia improves ...
(Date:10/11/2017)... ... October 11, 2017 , ... A ... pregnancy rates in frozen and fresh in vitro fertilization (IVF) transfer ... age to IVF success. , After comparing the results from the fresh and ...
(Date:10/10/2017)... , ... October 10, 2017 , ... ... Center’s FirstHand program has won a US2020 STEM Mentoring Award. Representatives of the ... for Excellence in Volunteer Experience from US2020. , US2020’s mission is to change ...
Breaking Biology Technology: