Showing posts from August 5, 2020

Measuring ecosystem disruption caused by marine heatwaves

 Nature Above, healthy bull kelp. Below, bull kelp degraded by a marine heatwave. DeWikiMan Marine heatwaves can displace thermal habitats by tens to thousands of kilometres, reports a study in Nature this week. This displacement represents the distance that an organism would have to travel to escape potentially stressful temperatures. The findings open new avenues of research to understand the potential impacts of anomalously warm ocean temperatures on marine species. Marine heatwaves are distinct periods of unusually warm ocean temperatures that can cause dramatic changes to ocean ecosystems, as inhabitants find themselves in waters that are warmer than they are accustomed to. Much of the research into these events focuses on the local impact to species such as corals, but does not take into account mobile organisms (fish, for example) that can travel to find their preferred conditions. To understand how species may have to redistribute under marine heatwave conditio

Zoonotic disease risk linked to human land use management

Nature Cattle in the Amazon. An Adobe photo. Human-managed ecosystems harbour more hosts of zoonotic disease than undisturbed habitats, a Nature study reveals. The research highlights the need for enhanced surveillance of agricultural, pastoral and urbanizing ecosystems, and to consider the disease-related health costs associated with land use and conservation planning. Zoonotic diseases, such as Ebola, Lassa fever and Lyme disease, are caused by pathogens that spread from animals to people. It is widely accepted that land use change — for example, the conversion of natural habitats to agricultural land or cities — influences the risk and emergence of zoonotic diseases in humans, but whether this is underpinned by predictable ecological changes has been unclear. Kate Jones and colleagues analysed 6,801 ecological systems and 376 host species worldwide to show that land use has global and systematic effects on local zoonotic host communities. There are more species and greater numbers o