Navigation Links
Marine research in the Brazilian rainforest

This release is available in German.

Until recent decades the Atlantic Rainforest covered a large area of today's Brazil from Amazonas to present-day Argentina. In the 1970s, after years of deforestation, this rain forest was almost completely destroyed, mainly replaced by cattle pastures. This study reveals an unexpected aspect of deforestation. Thorsten Dittmar's team and colleagues from Brazil and the USA show that the common practice of slash and burn left huge amounts of charcoal in the soil. This charcoal is washed out by rainfalls and transported by rivers into the Atlantic Ocean. The soluble fraction of charcoal is composed of extremely stable carbon compounds. The authors conclude that the amounts of these compounds dissolved in the ocean will increase due to human civilization. So far, the effects on marine microorganisms and the global carbon cycle are unknown.

Since way back mankind used fire to shape Earth's vegetation. This was common practice in the 16th century when European settlers came to Brazil, and the beginning of the end of the rain forest. Slash and burn during the centuries reduced its size of 1.3 million to a mere 100,000 square kilometers. What was left was 200-500 millions tons of charred carbon in the soils. These remnants are complex and extremely stable carbon compounds. During the rainy seasons the water elutes the soluble fractions and transports the carbon to the Atlantic Ocean, affecting biogeochemical cycles for centuries and millenia.

In earlier times, the Atlantic rain forest covered a large track of today's Brazil, reaching from 5 to 28 degree south latitude with an area of 1.3 million square kilometers. Until the midst of the 19th century about 95 per cent was intact, but the growing demand for cattle pastures led to massive slash and burn practice which ceased in 1973 leaving only 15 per cent of the original area unaffected. As of today only 8 per cent (100,000 square kilometers) are left.

Thorsten Dittmar and his group at the Max Planck Institute for Marine Microbiology analysed the samples in their laboratories at the University of Oldenburg which are an outpost station of the Bremen based Max Planck Institute. Their main research topic is the carbon cycle and the fate of the dissolved organic matter (DOM) in aquatic, mainly marine, systems. For the sample analysis of the present study they also used their ultrahigh resolution mass spectrometer.

Dittmar explains how they started their rain forest project: "A couple of years ago we detected telltale carbon compounds typical for burnt plant material and charcoal dissolved in ocean water. We speculated that the pre-harvest burning of sugar cane plantations and forest fires in Brazil was a major source. So, we as marine scientists, contacted our colleagues in Brazil, who had taken soil and water samples for years around the Paraiba do Sul river."

The results were surprising. Substantially more carbon compounds where discharged by the river than the annual procedure of pre-harvest burning of sugar cane plantations could produce. "When we plotted the results from the samples against time and compared this pattern with the amount of precipitation and the occurrence of fires, the relation became obvious. The charred carbon must have originated from the slash and burn period from much earlier times."

This assumption was confirmed by further experiments and data. The large scale slash and burn practice ended in 1973. The still practiced pre-harvest burning of the sugar cane plantations produces only 190-740 tons charred carbon annually, but the amount found in the river was three to sixteen times higher. The scientists extrapolated 50,000 to 70,000 tons for the annual load carried by rivers from the total area of the relict rain forest into the Atlantic Ocean. In the laboratory the soil of the rain forest gave the highest yield of carbon compounds in leaching experiments. More and more it became obvious that the sugar cane plantations were not the source, as also high concentrations of charred carbons were detected upstream of the river where only limited numbers of plantation were present.

"There are current discussions in the scientific community about using charred carbon to sequester carbon and thereby removing it from the active global carbon cycle. Our data clearly show that this is not a sustainable procedure, as sooner or later this carbon ends up in the oceans and alters the ecosystem. And we do not know anything about the consequences", Dittmar sums up his concerns. "The soluble fraction of charred carbon is extremely stable in the environment and withstands microbial activities. Therefore, we can trace it in the world's oceans, even in remote places of the deep sea. Our study suggests that this stable fraction of charred carbon in the deep sea will increase due to the increase of anthropogenic activities. The consequences on the marine microorganisms and the global carbon cycle are unknown."


Contact: Dr. Thorsten Dittmar

Related biology news :

1. Drivers of marine biodiversity: Tiny, freeloading clams find the key to evolutionary success
2. New milestone book documents changes in the south Florida marine ecosystem
3. First seabed sonar to measure marine energy effect on environment and wildlife
4. Paints and coatings containing bactericidal agent nanoparticles combat marine fouling
5. NOAA scholarship awarded to Jan Vicente to study the impact of ocean acidification on marine sponges
6. Stanford marine biologist Barbara Block wins Rolex Award for Enterprise
7. DNA evidence shows that marine reserves help to sustain fisheries
8. Deep sea animals stowaway on submarines and reach new territory
9. ORNL protein analysis investigates marine worm community
10. SeaSketch, the next generation of UCSBs MarineMap program, will aid marine spatial planning
11. NOAA discovers way to detect low-level exposure to seafood toxin in marine animals
Post Your Comments:
Related Image:
Marine research in the Brazilian rainforest
(Date:4/5/2017)... YORK , April 5, 2017 Today ... is announcing that the server component of the HYPR ... known for providing the end-to-end security architecture that empowers ... HYPR has already secured over 15 million ... makers including manufacturers of connected home product suites and ...
(Date:3/30/2017)... March 30, 2017  On April 6-7, 2017, ... Genome hackathon at Microsoft,s headquarters in ... will focus on developing health and wellness apps that ... Hack the Genome is the first hackathon for ... world,s largest companies in the genomics, tech and health ...
(Date:3/28/2017)... 2017 The report "Video Surveillance ... Servers, Storage Devices), Software (Video Analytics, VMS), and Service ... Forecast to 2022", published by MarketsandMarkets, the market was ... projected to reach USD 75.64 Billion by 2022, at ... base year considered for the study is 2016 and ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... Bay, Florida (PRWEB) , ... October 11, 2017 ... ... and Drug Administration (FDA) has granted orphan drug designation to SBT-100, its novel ... (sdAb) for the treatment of osteosarcoma. SBT-100 is able to cross the cell ...
(Date:10/10/2017)... ... October 10, 2017 , ... ... advancing targeted antibody-drug conjugate (ADC) therapeutics, today confirmed licensing rights that give ... Liposomal Nanoparticle), a technology developed in collaboration with Children’s Hospital Los Angeles ...
(Date:10/10/2017)... ... October 10, 2017 , ... Dr. Bob Harman, founder and CEO of ... Rotary Club. The event entitled “Stem Cells and Their Regenerative Powers,” ... Dr. Harman, DVM, MPVM was joined by two human doctors: Peter B. Hanson, ...
(Date:10/10/2017)... Oct. 10, 2017 SomaGenics announced the receipt ... to develop RealSeq®-SC (Single Cell), expected to be the ... RNAs (including microRNAs) from single cells using NGS methods. ... need to accelerate development of approaches to analyze the ... "New techniques for measuring levels of mRNAs in ...
Breaking Biology Technology: