Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 
Datenbankrecherche:

 

Amazon Freshwater Ecosystems Are Vulnerable to Degradation

04.02.2013
A study published in Conservation Letters this week found that freshwater ecosystems in the Amazon are highly vulnerable to environmental degradation. River, lake and wetland ecosystems—encompassing approximately one-fifth of the Amazon basin area—are being increasingly degraded by deforestation, pollution, construction of dams and waterways, and over-harvesting of plant and animal species.

The study was led by Dr. Leandro Castello, a research associate at the Woods Hole Research Center (WHRC), in collaboration with scientists from various institutions in the United States and Brazil. These included the Amazon Environmental Research Institute (IPAM), the University of California at Santa Barbara (UCSB), Brazil’s National Institute for Space Research (INPE), and The Nature Conservancy (TNC).

Damage to Amazon freshwater ecosystems greatly impacts Amazonians, who historically have been so dependent on freshwater ecosystem goods and services that they have been called ‘water peoples.’ Current per capita fish consumption in the Brazilian Amazon averages 94 kg/yr in riverine populations, which is almost six times the world average. Increasing fishing pressure has shrunk the size of harvested species, partly due to the progressive depletion of high-value, large-bodied species. A century ago, the mean maximum body length of the main species harvested in the basin was ~206 cm—today it is ~79 cm.

Science and policy in the Amazon have focused largely on forests and their associated biodiversity and carbon stocks. Three decades of effort have generated an understanding of some key biophysical transitions in the basin, and established a network of protected areas, largely designed to preserve forests and their biodiversity. Little attention has been paid to freshwater ecosystems, which through the hydrological cycle are interconnected to other ecosystems at local and distant locations, being highly sensitive to a broad array of human impacts.

“Despite some terrestrial protections that are high by global standards, this paper shows key gaps in protection for the Amazon’s freshwater systems and species,” commented Robin Abell, the Senior Freshwater Conservation Biologist at World Wildlife Fund. The Madeira River basin, for example, is threatened by oil exploration, deforestation and dams in its headwaters, even though protected areas cover 26% of the catchment area. “The pressures that the authors detail need to be addressed now, before conservation opportunities are lost. Restoration can be far costlier than proactive protection,” cautioned Abell.

The principal threat to most Amazon freshwater ecosystems is large-scale alteration of the basin’s natural hydrology. “There are a total of 154 hydroelectric dams in operation, 21 in construction, and plans to construct 277 additional dams in the future. There are also thousands of small dams located in small streams to provide water for cattle,” noted coauthor Marcia Macedo of WHRC. “These infrastructure projects, together with deforestation-induced changes to regional rainfall, could fundamentally change the hydrology of Amazon freshwater systems,” she added. The study suggests that, if uncontrolled, such hydrological alterations could disrupt fish migrations and associated fishery yields, threatening riverine livelihoods and food security.

Adequate protection of Amazon freshwater ecosystems requires broadening the forest-centric focus of prevailing environmental management and conservation strategies to encompass aquatic ecosystems. By building upon existing protected areas, it is possible to develop a river catchment-based conservation framework that protects both aquatic and terrestrial ecosystems, effectively protecting the Amazon river-forest system. The Amazon watershed spans six countries, with Brazil, Bolivia, and Peru accounting for most of the area. Therefore, "A pan-Amazonian, catchment-based approach is critical, in addition to national conservation and management efforts," said coauthor Dr. Laura Hess of Earth Research Institute, UCSB.

“There are environmental issues everywhere, but the case with Amazon freshwater ecosystems is different, because no one talks about it. Their problem has been concealed,” said Castello. Emphasizing the need for a shift, he added, “Significant strides in Amazon conservation have been on deforestation because deforestation has been studied and monitored year after year. We now need to do the same for these aquatic ecosystems.”

The study can be found here: http://onlinelibrary.wiley.com/doi/10.1111/conl.12008/abstract

A map and the images can also be accessed here:
http://whrc.org/news/pressroom/index.html
Castello, L., McGrath, D.G., Hess, L.L., Coe, M.T., Lefebvre, P.A., Petry, P., Macedo, M.N., Reno, V., Arantes, C.C. 2012. The vulnerability of Amazon freshwater ecosystems. Conservation Letters DOI: 10.1111/conl.12008

Ian Vorster | Newswise
Further information:
http://www.whrc.org

More articles from Ecology, The Environment and Conservation:

nachricht How does the loss of species alter ecosystems?
18.05.2017 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig

nachricht Excess diesel emissions bring global health & environmental impacts
16.05.2017 | International Institute for Applied Systems Analysis (IIASA)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Lässt sich mit Boten-RNA das Immunsystem gegen Staphylococcus aureus scharf schalten?

Staphylococcus aureus ist aufgrund häufiger Resistenzen gegenüber vielen Antibiotika ein gefürchteter Erreger (MRSA) insbesondere bei Krankenhaus-Infektionen. Forscher des Paul-Ehrlich-Instituts haben immunologische Prozesse identifiziert, die eine erfolgreiche körpereigene, gegen den Erreger gerichtete Abwehr verhindern. Die Forscher konnten zeigen, dass sich durch Übertragung von Protein oder Boten-RNA (mRNA, messenger RNA) des Erregers auf Immunzellen die Immunantwort in Richtung einer aktiven Erregerabwehr verschieben lässt. Dies könnte für die Entwicklung eines wirksamen Impfstoffs bedeutsam sein. Darüber berichtet PLOS Pathogens in seiner Online-Ausgabe vom 25.05.2017.

Staphylococcus aureus (S. aureus) ist ein Bakterium, das bei weit über der Hälfte der Erwachsenen Haut und Schleimhäute besiedelt und dabei normalerweise keine...

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: Orientierungslauf im Mikrokosmos

Physiker der Universität Würzburg können auf Knopfdruck einzelne Lichtteilchen erzeugen, die einander ähneln wie ein Ei dem anderen. Zwei neue Studien zeigen nun, welches Potenzial diese Methode hat.

Der Quantencomputer beflügelt seit Jahrzehnten die Phantasie der Wissenschaftler: Er beruht auf grundlegend anderen Phänomenen als ein herkömmlicher Rechner....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Tumult im trägen Elektronen-Dasein

Ein internationales Team von Physikern hat erstmals das Streuverhalten von Elektronen in einem nichtleitenden Material direkt beobachtet. Ihre Erkenntnisse könnten der Strahlungsmedizin zu Gute kommen.

Elektronen in nichtleitenden Materialien könnte man Trägheit nachsagen. In der Regel bleiben sie an ihren Plätzen, tief im Inneren eines solchen Atomverbunds....

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

IHR
JOB & KARRIERE
SERVICE
im innovations-report
in Kooperation mit academics
Veranstaltungen

Meeresschutz im Fokus: Das IASS auf der UN-Ozean-Konferenz in New York vom 5.-9. Juni

24.05.2017 | Veranstaltungen

Diabetes Kongress in Hamburg beginnt heute: Rund 6000 Teilnehmer werden erwartet

24.05.2017 | Veranstaltungen

Wissensbuffet: „All you can eat – and learn”

24.05.2017 | Veranstaltungen

 
VideoLinks
B2B-VideoLinks
Weitere VideoLinks >>>
Aktuelle Beiträge

DFG fördert 15 neue Sonderforschungsbereiche (SFB)

26.05.2017 | Förderungen Preise

Lässt sich mit Boten-RNA das Immunsystem gegen Staphylococcus aureus scharf schalten?

26.05.2017 | Biowissenschaften Chemie

Unglaublich formbar: Lesen lernen krempelt Gehirn selbst bei Erwachsenen tiefgreifend um

26.05.2017 | Gesellschaftswissenschaften