Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The Peninsula’s earliest agricultural systems were unsustainable

18.09.2008
A team of Catalan and Andalusian researchers has proved that the first agricultural systems on the Iberian Peninsula became ever more unsustainable with the passage of time. The study involved the analysis of fossilised grains of wheat and barley from Los Castillejos (Granada), an area of archaeological remains where cereals were cultivated between 4000 and 2500 BCE.

Mónica Aguilera, an engineer from the Vegetable Physiology Unit at the University of Barcelona (UB) and co-author of the study, told SINC that the natural levels of stable carbon and nitrogen isotopes were measured in order to estimate the yield and nutritional status of the ancient crops. “The size of the grain and levels of the carbon 13 (13C) isotopes allowed us to estimate yield, while the nutritional status of the crop was analysed by measuring levels of the nitrogen 15 (15N) isotopes,” the researcher explained.

Figures revealed by the study show a reduction of around 35% in the yield of wheat crops and 30% in barley between the years 4000 and 2500 BCE (end of the Bronze Age). The average weight of the grains of these cereals also fell by 10 miligrammes (33%) and 12 mg (38%) respectively. The research also revealed a 33% reduction in the nitrogen content of the wheat grains and 56% in barley.

“These figures suggest that the agricultural system of the region in the south east of the peninsula became unsustainable over time, and that this was not due to a lack of water,” says Aguilera. The scientists have looked into the water available to the cereals by the end of their cultivation period, based upon the carbon isotope component, and have obtained approximately constant values (around 120 mm) for the entire period studied, which makes it seem the decline in yield had no apparent relation to drought events. These estimates, however, contrast with current rain measurements in the area (around 60 mm in April and May).

The researchers have also observed a close relationship between the seasonal variations of the cereals and those of weeds. Barley was most abundant at the same time as wasteland weeds (common in uncultivated land and rubbish tips, such as nettles, mallow, celery, goosefoot and clover), while wheat flourished at the same time as weeds more characteristic of land cultivated with cereals (such as poppies, plantains, knotweeds and various grassy plants).

“This suggests that there was a separate system of cultivation for the two cereals: barley was possibly relegated to marginal areas, while the potentially more fertile fields were reserved for wheat, which was more abundant and very probably the principal crop for human consumption in the primitive agricultural systems of the south east of the peninsula,” said Aguilera.

The results of the study show a link between the decline in the status of the crops and a progressive loss in soil fertility, and reinforce the hypothesis that the first agricultural activities in the Mediterranean area had a negative impact on ecological and environmental conditions there.

The scientists chose the Los Castillejos archaeological site because it shows evidence of a continuous period of cereal cultivation over more than 1,500 years, starting in the Neolithic, when agriculture first appears in the region. However, they have contrasted their data with other results from Arkaute (Álava), Guadahortuna (Granada) and various areas in Catalonia and Castilla-La Mancha, as well as with other sites in Syria and the eastern Mediterranean.

Researchers from the University of Barcelona, the University of Lleida and the Archaeology Museum of Catalonia, as well as archaeologists from the University of Granada and the Andalusian Centre for Iberian Archaeology (University of Jaén), took part in the study, “which uses original means to apply a range of novel methodologies derived from the use of stable carbon and nitrogen isotopes in palaeoclimatic and environmental reconstruction,” according to Aguilera.

| alfa
Further information:
http://www.plataformasinc.es

More articles from Agricultural and Forestry Science:

nachricht New research recovers nutrients from seafood process water
31.10.2018 | Chalmers University of Technology

nachricht Plant Hormone Makes Space Farming a Possibility
17.10.2018 | Universität Zürich

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Epoxy compound gets a graphene bump

14.11.2018 | Materials Sciences

Microgel powder fights infection and helps wounds heal

14.11.2018 | Health and Medicine

How algae and carbon fibers could sustainably reduce the athmospheric carbon dioxide concentration

14.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>