Human Pressure on Ocean Ecosystems
Study Shows Extent of Harmful Impact to Global Marine Environment
A study published in Science magazine describes the human impacts on global marine ecosystems in a visual map of temperature, uv radiation and acidification
A study published in the peer review journal Science shows that over forty percent of the world oceans are greatly impacted by human activity. Titled A Global Map of Human Impact on Marine Ecosystems, the report details the negative effects that stem from over fishing, farm chemical run off and industrial pollution worldwide.
In announcing the study, Ocean Conservancy Senior Scientist and co-author Dr. Dennis Heinemann says, "On a global scale, the study determined that coral reefs and sea-grass habitats, places important to maintaining the diversity and productivity of ocean life, are suffering from some of the most significant cumulative threats from humans. We fear that few areas of the ocean are left without compromised resilience in the face of the ongoing and increasing threats of overfishing, pollution and ocean climate change."
Map Components Measured - Researchers based at National Center for Ecological Analysis and Synthesis at the University of California – Santa Barbara looked at 17 different data sets of different human related activities in 20 different ecosystems to develop a map that visually displays changes in ocean surface temperature, ultraviolet radiation, and acidification. The East Coast of the United States, North Sea, East China Sea, and Mediterranean Sea are among those most greatly affected by human actions. The waters near the poles were least affected from peoples' activities.
Ecosystems at Risk - Habitat areas at greatest risk are the coral reefs that protect marine life and wave erosion, seagrass beds that nurture juvenile fish, and mangrove forests that prevent coastal erosion and rocky seamounts. These ecosystems are seen as vital to maintaining the diversity of sea life. Areas at less risk are soft-bottom regions and open ocean waters.
The Research Process - The global map was developed through a four-step process:
- Quantification of human impact to each distinct ecosystem. An example is negative effect of farm chemical run off on coral beds, while kelp forests see less of an impact
- Gathering data on distribution of marine ecosystems and impact of human activities
- Processing ecosystem and human influence data to develop scores for human impacts for each global area
- Verifying the study's estimates to conditions found in marine ecosystem through previous research
Previous research has only focused on a single unique human impact or specific ecosystem. The global mapping project brings together the whole world array of human influences and environments.
One beneficial outcome from the study is the opportunity for natural resource managers and conservation groups to prioritize areas were human activities need to reduced or regulated. Policy makers have started this effort through establishment of marine protected areas and use of ecosystem based management.
In the same study announcement, co-author Kimberly Selkoe says, "Conservation and management groups have to decide where, when, and what to spend their resources on. Whether one is interested in protecting ocean wilderness, assessing which human activities have the greatest impact, or prioritizing which ecosystem types need management intervention, our results provide a strong framework for doing so."
