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 New approach for environmental test on livestock drugs
27.07.2016 | Universität Zürich

nachricht Managing an endangered river across the US-Mexico border
18.07.2016 | 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: Neue Bildgebungsmethode macht Sauerstoffgehalt in Gewebe sichtbar

Wie blickt man in den menschlichen Körper, ohne zu operieren? Die Suche nach neuen Lösungen ist nach wie vor eine wichtige Aufgabe der Medizinforschung. Eine der großen Herausforderungen auf diesem Feld ist es, Sauerstoff in Gewebe sichtbar zu machen. Ein Team um Prof. Vasilis Ntziachristos, Inhaber des Lehrstuhls für Biologische Bildgebung an der Technischen Universität München (TUM) und Direktor des Instituts für Biologische und Medizinische Bildgebung am Helmholtz Zentrum München, hat dazu einen neuen Ansatz entwickelt.

Einen Königsweg, um den Sauerstoffgehalt in Gewebe sichtbar zu machen, schien es bislang nicht zu geben. Viele unterschiedliche Verfahren wurden ausprobiert,...

Im Focus: Wie biologische Vielfalt das Ohr fit macht

Göttinger Hörforschung mit neuen Erkenntnissen: Das Ohr setzt Synapsen mit verschiedenen Eigenschaften ein, um unterschiedlich lauten Schall zu verarbeiten. Forschungsergebnisse veröffentlicht in der Fachzeitschrift „Proceedings of the National Academy of Sciences“

Der menschliche Hörsinn verarbeitet einen immensen Bereich an Lautstärken. Wie schafft es das Ohr, etwa über eine Million Schalldruck-Variationen zu...

Im Focus: Ultrakompakter Photodetektor

Der Datenverkehr wächst weltweit. Glasfaserkabel transportieren die Informationen mit Lichtgeschwindigkeit über weite Entfernungen. An ihrem Ziel müssen die optischen Signale jedoch in elektrische Signale gewandelt werden, um im Computer verarbeitet zu werden. Forscher am KIT haben einen neuartigen Photodetektor entwickelt, dessen geringer Platzbedarf neue Maßstäbe setzt: Das Bauteil weist eine Grundfläche von weniger als einem Millionstel Quadratmillimeter auf, ohne die Datenübertragungsrate zu beeinträchtigen, wie sie im Fachmagazin Optica nun berichten. (DOI: 10.1364/OPTICA.3.000741)

Die neuentwickelten Photodetektoren, die weltweit kleinsten Photodetektoren für die optische Datenübertragung, eröffnen die Möglichkeit, durch integrierte...

Im Focus: Self-assembling nano inks form conductive and transparent grids during imprint

Transparent electronics devices are present in today’s thin film displays, solar cells, and touchscreens. The future will bring flexible versions of such devices. Their production requires printable materials that are transparent and remain highly conductive even when deformed. Researchers at INM – Leibniz Institute for New Materials have combined a new self-assembling nano ink with an imprint process to create flexible conductive grids with a resolution below one micrometer.

To print the grids, an ink of gold nanowires is applied to a substrate. A structured stamp is pressed on the substrate and forces the ink into a pattern. “The...

Im Focus: Neues Forschungsnetzwerk für Mikrobiomforschung

Mikroben und Viren haben weitreichenden Einfluss auf die Gesundheit von Mensch und Tier. Die neu gegründete "Austrian Microbiome Initiative" (AMICI) fördert die nationale Mikrobiomforschung und vernetzt MedizinerInnen und ForscherInnen verschiedenster Fachrichtungen zur Nutzung von Synergien.

Bakterien, Archaeen, Pilze, Viren – Milliarden von Mikroorganismen leben in Symbiose in und auf Menschen und Tieren. Diese mikroskopisch kleinen Lebewesen...

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

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

BAuA lädt zur Konferenz „Arbeiten im Büro der Zukunft“ ein

29.07.2016 | Veranstaltungen

Fachkongress zu additiven Fertigungsverfahren am 14. und 15. September in Aachen

28.07.2016 | Veranstaltungen

Rheumatologen tagen in Frankfurt: Mehr Forschung für Rheuma gefordert

28.07.2016 | Veranstaltungen

 
B2B-VideoLinks
Weitere VideoLinks >>>
Aktuelle Beiträge

Forschung gibt Impulse für Innovationen

29.07.2016 | Förderungen Preise

Molekulare Störenfriede statt Antibiotika? Wie Proteine Kommunikation zwischen Bakterien verhindern

29.07.2016 | Biowissenschaften Chemie

Internationales Forscherteam deckt grundlegende Eigenschaften des Spin-Seebeck-Effekts auf

29.07.2016 | Physik Astronomie