UD researchers studying ‘fingerprint’ left on seafloor by Hurricane Sandy
Beneath the 20-foot waves that crested off Delaware’s coast during Hurricane Sandy, thrashing waters reshaped the floor of the ocean, churning up fine sand and digging deep ripples into the seabed. Fish, crustaceans and other marine life were blasted with sand as the storm sculpted new surfaces underwater.
UD scientists cued up their instruments to document the offshore conditions before, during and after Sandy’s arrival to scrutinize the differences and better predict the environmental impact of future storms. (more…)
Blanket bogs, which provide vital habitats for a unique range of plants, birds, small mammals, reptiles and amphibians, are at risk of declining as a result of climate change.
Research by the Universities of Exeter and Bristol in the UK and Macquarie University in Australia, published in the journal Nature Climate Change, shows for the first time how rising temperatures will threaten these sensitive ecosystems.
The study highlights the urgency of developing a plan to protect these important habitats.
Found in wet, coastal areas of high latitude regions, blanket bogs cover around 700,000 hectares of land in the UK, much of it designated as a Site of Special Scientific Interest (SSSI). Blanket bogs are found in the north and west of the UK, extending from Devon in the south to Shetland in the north, and it has been estimated that 10 to15 per cent of the world’s blanket bog occurs in Britain. As well as being crucial in supporting wildlife, blanket bogs also capture and store large amounts of carbon, helping to mitigate against climate change, and reduce the risk of flooding, by slowing down water flow. With some blanket peat being over 9,000 years old, they also hold historically-significant archaeological material. (more…)
Washington, D.C. – For years, scientists have debated how big a role elephants play in toppling trees in South African savannas. Tree loss is a natural process, but it is increasing in some regions, with cascading effects on the habitat for many other species. Using high resolution 3-D mapping, Carnegie scientists have for the first time quantitatively determined tree losses across savannas of Kruger National Park. They found that elephants are the primary agents—their browsing habits knock trees over at a rate averaging 6 times higher than in areas inaccessible to them. The research also found that elephants prefer toppling trees in the 16-to-30 foot (5-8 m) range, with annual losses of up to 20% in these height classes. The findings, published in Ecology Letters, bolster our understanding of elephant conservation needs and their impacts, and the results could help to improve savanna management practices.
“Previous field studies gave us important clues that elephants are a key driver of tree losses, but our airborne 3-D mapping approach was the only way to fully understand the impacts of elephants across a wide range of environmental conditions found in savannas,” commented lead author Greg Asner of Carnegie’s Department of Global Ecology. “Our maps show that elephants clearly toppled medium-sized trees, creating an “elephant trap” for the vegetation. These elephant-driven tree losses have a ripple effect across the ecosystem, including how much carbon is sequestered from the atmosphere.”(more…)
Landscaping with native vegetation helps local bird species
Yards with plants that mimic native vegetation offer birds “mini-refuges” and help to offset losses of biodiversity in cities, according to results of a study published on August 22, 2012in the journal PLOS ONE.
“Native” yards support birds better than those with traditional grass lawns and non-native plantings.
Researchers conducted the study through the National Science Foundation’s (NSF) Central Arizona-Phoenix Long-Term Ecological Research (LTER) site, one of 26 such sites around the globe in ecosystems from coral reefs to deserts, from forests to grasslands. (more…)
Sustainable management of a huge, complex and valuable resource such as the ocean requires a comprehensive metric that did not exist until now. In the Aug. 16 edition of Nature a broad group of scientists including Heather Leslie, the Sharpe Assistant Professor of Environmental Studies, describes the Ocean Health Index. The index rates coastal places, from regions to nations, on 10 goals: artisanal fishing opportunity, biodiversity, carbon storage, clean waters, coastal livelihoods and economies, coastal protection, food provision, natural products, sense of place, and tourism and recreation. Leslie recently answered questions posed by David Orenstein.
How does the Ocean Health Index’s focus on integrating human factors make it different and valuable?
Recognizing people’s integral roles in ocean ecosystems, this index evaluates how well the ocean provides 10 key benefits to people and how well we are protecting its ability to do so in the future. (more…)
When a carnivore becomes extinct, other predatory species could soon follow, according to new research.
Scientists have previously put forward this theory, but a University of Exeter team has now carried out the first experiment to prove it.
Published today (15 August 2012) in the Royal Society journal Biology Letters, the study shows how the demise of one carnivore species can indirectly cause another to become extinct. The University of Exeter team believes any extinction can create a ripple effect across a food web, with far-reaching consequences for many other animals. (more…)
As recreational fishing activity has reduced predators in many of Cape Cod’s salt marsh ecosystems, Sesarma crabs have feasted on grasses, causing dramatic die-offs of the marshes, according to a new study. The researchers assessed the “trophic cascade” in several experiments that also ruled out alternative explanations for the problem.
PROVIDENCE, R.I. [Brown University] — Recreational fishing is a major contributor to the rapid decline of important salt marshes along Cape Cod because it strips top predators such as striped bass, blue crabs, and smooth dogfish out of the ecosystem, according to new research by Brown University ecologists.(more…)
A team of researchers, including scientists from Woods Hole Oceanographic Institution (WHOI), discovered a massive bloom of phytoplankton beneath ice-covered Arctic waters. Until now, sea ice was thought to block sunlight and limit the growth of microscopic marine plants living under the ice.
The amount of phytoplankton growing in this under-ice bloom was four times greater than the amount found in neighboring ice-free waters. The bloom extended laterally more than 100 kilometers (62 miles) underneath the ice pack, where ocean and ice physics combined to create a phenomenon that scientists had never seen before. (more…)
