GGR227H5 Lecture Notes - Lecture 13: Urchin Barren, Kelp Forest, Marine Ecosystem
Document Summary
Ecosystem services provided by the marine environment are fundamental to human health and well-being. Despite this, many marine systems are being degraded to an extent that may reduce their capacity to provide these ecosystem services. Initial research on the relationship between biodiversity and ecosystem service provision suggests that ecosystem service provision decreases with a decrease in biodiversity. An example of such a phase shift resulted from the drastic decline in sea otter populations observed along the north-west coast of the united states as an indirect consequence of human exploitation of marine resources (springer et al. , 2003). Sea urchins were released from predation by sea otters and thus kelp forests faced extreme herbivory by the increasing sea urchin populations. This prevented the regrowth of the foliose macroalgae, leading to a transformation of the coastal areas from a lush forest to urchin barrens (stewart and konar, 2012).
