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Latest Trophic dynamics Stories

Foundational Concept Of Ecology Tested With Experiment
2012-06-25 10:38:21

Acting through links between four trophic levels and across two ecosystems, purple loosestrife altered life in nearby ponds An elementary school science activity asks children who have each been assigned a wetland plant or animal to connect themselves with string and tape to other “organisms” their assigned plant or animal interacts with in some way. Once an ecosystem web has been created, the teacher describes an event that affects one “organism.” That...

Prey Distribution, Not Biomass, Key To Marine Food Chain
2012-05-03 03:30:03

A new study has found that each step of the marine food chain is clearly controlled by the trophic level below it — and the driving factor influencing that relationship is not the abundance of prey, but how that prey is distributed. The importance of the spatial pattern of resources — sometimes called “patchiness” — is gaining new appreciation from ecologists, who are finding the overall abundance of food less important than its density and ease of access to...

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2011-06-07 08:43:40

A new study by researchers at the Virginia Institute of Marine Science (VIMS) shows that jellyfish are more than a nuisance to bathers and boaters, drastically altering marine food webs by shunting food energy from fish toward bacteria. An apparent increase in the size and frequency of jellyfish blooms in coastal and estuarine waters around the world during the last few decades means that jellies' impact on marine food webs is likely to increase into the future. The results of the study, led...

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2011-01-22 09:02:30

Catalan researchers have studied the marine trophic network in Mauritania, on the north west coast of Africa, which is an extremely heavily exploited fishing area, as well as being home to two of the world's most threatened species of marine mammal "“ the monk seal and the Atlantic hump-backed dolphin. The results of the study show that industrial and traditional fishing activities along the coast are putting these mammals and local marine ecosystems at great danger. The researchers...

2010-11-25 22:11:14

A measure widely advocated as a means of assessing the health of marine ecosystems is an ineffective guide to trends in biodiversity, and more direct monitoring is needed, a new study has found. The findings "“ published this week in Nature "“ followed an examination of  whether changes in fishery catches reflect changes in the structure of marine food webs, and therefore are a suitable guide to assess the impacts of fishing on marine ecosystem health. CSIRO Wealth from...

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2010-11-18 09:24:47

Inaccurate conclusions may have been reached in many ecosystems The most widely adopted measure for assessing the state of the world's oceans and fisheries led to inaccurate conclusions in nearly half the ecosystems where it was applied. The new analysis was performed by an international team of fisheries scientists, and is reported in this week's issue of the journal Nature. "Applied to individual ecosystems it's like flipping a coin; half the time you get the right answer and half the time...

2010-11-17 21:46:57

The most widely adopted measure for assessing the state of the world's oceans and fisheries led to inaccurate conclusions in nearly half the ecosystems where it was applied according to new analysis by an international team led by a University of Washington fisheries scientist. "Applied to individual ecosystems it's like flipping a coin, half the time you get the right answer and half the time you get the wrong answer," said Trevor Branch, a UW assistant professor of aquatic and fishery...

2010-06-25 16:17:47

People who fish for a living pursue top profits, not necessarily top predators, according to the first-ever analysis of worldwide catch and economic data for the past 55 years. This differs from the observation raised 10 years ago that humans were "fishing down" the food web. It was assumed that catches of the predators at the top of the food chain, such as halibut and tuna, were declining after fishers started landing more fish from lower on the food chain, such as herring and anchovies. The...

2009-11-03 18:40:00

One of the main objectives of marine biology is to understand the trophic food chains involving microbian plankton. That is, to study the sequence of organisms in relation to their nutrition, given that live organisms can be classified from the perspective of nutrition. In this classification each organism is at one level and all these levels are united one to the other, forming a chain. In this succession of stages or levels an organism feeds itself and is devoured. The structure of this...

2009-08-06 14:19:52

The findings, published in this week's issue of Science, conclude that food-web stability is enhanced when many diverse predator-prey links connect high and intermediate trophic levels. The computations also reveal that small ecosystems follow other rules than large ecosystems: differences in the strength of predator-prey links increase the stability of small webs, but destabilize larger webs.Natural ecosystems consist of interwoven food chains, in which individual animal or plant species...


Word of the Day
abrosia
  • Wasting away as a result of abstinence from food.
The word 'abrosia' comes from a Greek roots meaning 'not' and 'eating'.