Sewage effects on food sources and diet of benthic foraminifera living in oxic sediment: a microcosm experiment

first_imgA microcosm experiment was conducted to investigate the effects of sewage-derived particulate organic matter (POM) on the food sources and diets of two species of intertidal benthic foraminifera, Ammonia beccarii and Haynesina germanica, using lipid biomarkers to determine trophic relationships. The lipid content of the sediment and associated micro-organisms was a guide to potential food sources while that of the foraminifera was a guide to what they had actually eaten. Six microcosm tanks were established, with constant salinity, temperature and oxygen content, and each with a thin layer of sediment containing living foraminifera. Three microcosms were used as controls and three were treatments to which the POM from secondary treated sewage was added. Each microcosm was treated as a single replicate (to avoid pseudoreplication). The experiment was run for 38 days. The results showed that the food sources (from the sediment) and the diet of the foraminifera did not significantly differ in the controls or the treatments, but quantities of fatty acids decreased in both the sediment system and the foraminifera over the duration of the experiment. It is concluded that sewage-POM (secondary treatment) does not have a direct effect on the food sources of the foraminifera or their diet. The foraminifera did not feed directly on the sewage-derived POM, nor did the addition of sewage stimulate growth of micro-organisms associated with the sediment system. However, recent field data collected by the authors provides evidence that season plays an important role in foraminiferal response to organic pollution (OP), and microcosm sediment might have been unknowingly collected at a time when foraminifera are now known not to respond to OP, i.e. in summer.last_img read more

USS Santa Fe Arrives at Changi Naval Base

first_img View post tag: USS USS Santa Fe Arrives at Changi Naval Base Back to overview,Home naval-today USS Santa Fe Arrives at Changi Naval Base View post tag: Navy View post tag: Base View post tag: News by topic October 24, 2013 View post tag: Changi View post tag: Defense View post tag: Defence Share this article View post tag: Arrives Training & Education View post tag: SANTA View post tag: Naval The Los Angeles-class, fast attack submarine USS Santa Fe (SSN 763) arrived at Changi Naval Base, Singapore, Oct. 23, for a visit as part of her deployment to the Western Pacific.With a crew of approximately 135 men, Santa Fe will conduct a multitude of missions and showcase the latest capabilities of the submarine fleet.“Santa Fe is honored to be guests of Singapore and the Republic of Singapore Navy (RSN),” said Cmdr. Timothy J. Poe, Santa Fe’s commanding officer. “The wealth of culture that my crew will experience in this great country will enhance cooperation and understanding between the U.S. Navy and our critical ally, the RSN.”Santa Fe is a preeminent weapon in the nation’s naval arsenal. Exercising dominant control of the littoral and open sea, Santa Fe prepares the battle space, promotes maritime security, and deters aggression across the globe.“This is a great opportunity for our Sailors to experience the world and get some much needed rest,” said Gonzalez. “Our motto is ‘Fight Hard, Play Hard’ – we’ve done the first part of our motto, now it’s time for the second.”This will be the first visit to Singapore for the majority of the crew and the excitement can be sensed throughout the ship.“I can’t wait to try some different food and experience the culture of another country,” said Culinary Specialist Seaman Dustin Bullock. “I’m also excited about catching up on Kentucky Wildcat football!”Santa Fe, named after the city of Santa Fe, N. M. is homeported in Pearl Harbor, Hawaii, and is assigned to Commander, Submarine Squadron 7.Measuring more than 360 feet long and weighing more than 6,800 tons when submerged, Santa Fe is among the world’s stealthiest platforms. This submarine is capable of supporting a multitude of missions including anti-submarine warfare, anti-surface ship warfare, strike, naval special warfare involving special operations forces, and intelligence, surveillance and reconnaissance.[mappress]Press Release, October 24, 2013; Image: US Navy View post tag: Felast_img read more