The chemical breakdown of marine derived reactive nitrogen transported to the land as seabird guano represents a significant source of ammonia (NH3) in areas far from other NH3 sources. Measurements made at tropical and temperate seabird colonies indicate substantial NH3 emissions, with emission rates larger than many anthropogenic point sources. However, several studies indicate that thermodynamic processes limit the amount of NH3 emitted from guano, suggesting that the percentage of guano volatilizing as NH3 may be considerably lower in colder climates. This study undertook high resolution temporal ammonia measurements in the field and coupled results with modelling to estimate NH3 emissions at a temperate puffin colony and two sub-polar penguin colonies (Signy Island, South Orkney Islands and Bird Island, South Georgia) during the breeding season. These emission rates are then compared with NH3 volatilization rates from other climates. Ammonia emissions were calculated using a Lagrangian atmospheric dispersion model, resulting in mean emissions of 5 μg m-2 s-1 at the Isle of May, 12 μg m-2 s-1 at Signy Island and 9 μg m-2 s-1 at Bird Island. The estimated percentage of total guano nitrogen volatilized was 5% on the Isle of May, 3% on Signy and 2% on Bird Island. These values are much smaller than the percentage of guano nitrogen volatilized in tropical contexts (31-65%). The study confirmed temperature, wind speed and water availability have a significant influence on the magnitude of NH3 emissions, which has implications for reactive nitrogen in both modern remote regions and pre-industrial atmospheric composition and ecosystem interactions.
Fire danger is on Dave Roberts’ mind as Dodgers head to San Francisco Dodgers hit seven home runs, sweep Colorado Rockies When Corey Seager walked in the next at-bat, the Dodgers ended their half of the first without recording an out as Widener hit his 25-pitch limit for the inning. Batting in the three hole, Justin Turner hit an infield single off the right-handed Widener’s glove to load the bases for Cody Bellinger. It took five pitches before the reigning National League MVP cleared the bases by hitting a 94 mile per hour fastball into the right field seats for a grand slam. Newsroom GuidelinesNews TipsContact UsReport an Error How Dodgers pitcher Ross Stripling topped the baseball podcast empire As the Los Angeles Dodgers prepared for Sunday’s exhibition against the Arizona Diamondbacks, Dodger manager Dave Roberts said he would use regular-season lineups to prepare for Thursday’s opener.And in the Dodgers’ 9-2 win on Sunday, the team got its first chance to see what its revamped offense looks like against an actual opponent.It all started in the bottom of the first inning. And fittingly, it began with right fielder Mookie Betts, the former American League MVP acquired in a blockbuster trade from the Red Sox in February.Betts led the frame off with a walk. Max Muncy followed with a walk of his own, the pair combining to face 14 pitches from Arizona starter Taylor Widener. Cody Bellinger homer gives Dodgers their first walkoff win of season The top of the order delivered again in the third inning on a sacrifice fly from Turner and an RBI single from Bellinger, driving in Betts and Muncy respectively.Bellinger added an RBI single in the seventh to finish the game 3-for-4 with six RBIs. All told, the Dodgers’ starting 1-5 hitters went 9-for-13 with three walks.The Dodgers enjoyed success on the mound on Sunday, too, thanks to the play of rookie Mitchell White.The former second-round pick threw five innings, allowing one earned run and one hit with two strikeouts and no walks. The one hit was a home run by Ketel Marte in the first inning, but White retired the next 14 batters he faced.The goal was for White to pitch four innings on Sunday. But he breezed through the target in 44 pitches, so Roberts called on him for the fifth inning. Help was warming up in the bullpen just in case, but White needed just 10 pitches to retire the side and qualify for the win.Related Articles Dodgers’ Max Muncy trying to work his way out of slow start The bullpen contributed four innings. Adam Kolarek and A.J. Ramos combined for a shutout sixth, while Victor Gonzalez allowed one earned run in two innings work. Closer Kenley Jansen finished the game with a perfect ninth.That type of pitching performance was more than enough given how the Dodgers hit on Sunday.