Subsurface pH and carbonate saturation state of aragonite on the Chinese side of the North Yellow Sea: seasonal variations and controls Biogeosciences DOI 10.5194/bg-11-1103-2014 26 February 2014 Based upon eight field surveys conducted between May 2011 and May 2012, we investigated seasonal variations in pH, carbonate saturation state of aragonite, and ancillary data on the Chinese side of the North Yellow Sea. Read more
Exploring local adaptation and the ocean acidification seascape – studies in the California Current Large Marine Ecosystem Biogeosciences DOI 10.5194/bg-11-1053-2014 24 February 2014 Here we present the OMEGAS strategy of co-locating sensors and oceanographic observations with biological studies on benthic marine invertebrates, specifically measurements of functional traits such as calcification-related processes and genetic variation in populations that are locally adapted to conditions in a particular region of the coast. Read more
Regional variability of acidification in the Arctic: a sea of contrasts Biogeosciences DOI 10.5194/bg-11-293-2014 23 January 2014 In this study, we use an ocean-only general circulation model, with embedded biogeochemistry and a comprehensive description of the ocean carbon cycle, to study the response of pH and saturation states of calcite and aragonite to rising atmospheric pCO2and changing climate in the Arctic Ocean. Read more
Weathering by tree-root-associating fungi diminishes under simulated Cenozoic atmospheric CO2decline Biogeosciences DOI 10.5194/bg-11-321-2014 23 January 2014 We report experimental evidence for a negative feedback across a declining Cenozoic [CO2]a range from 1500 to 200 ppm, whereby low [CO2]a curtails mineral surface alteration via trenching and etch pitting by arbuscular mycorrhizal (AM) and ectomycorrhizal (EM) fungal partners of tree roots. Read more
Seasonal variations of sea–air CO2 fluxes in the largest tropical marginal sea (South China Sea) based on multiple-year underway measurements Biogeosciences DOI 10.5194/bg-10-7775-2013 29 November 2013 Based upon 14 field surveys conducted between 2003 and 2008, this paper shows that the seasonal pattern of sea surface partial pressure of CO2 (pCO2) and sea–air CO2 fluxes differed among four different physical–biogeochemical domains in the South China Sea proper. Read more
Ratios among atmospheric trace gases together with winds imply exploitable information for bird navigation: a model elucidating experimental results Biogeosciences DOI 10.5194/bg-10-6929-2013 4 November 2013 A model of avian goal-oriented navigation is described that is based on two empirical findings building a bridge from ornithology to atmospheric chemistry. Read more
Nitrous Oxide (N2O) production in axenic Chlorella vulgaris microalgae cultures: evidence, putative pathways, and potential environmental impacts Biogeosciences DOI 10.5194/bg-10-6737-2013 25 October 2013 Using antibiotic assays and genomic analysis, this study demonstrates nitrous oxide (N2O) is generated from axenic Chlorella vulgaris cultures. In batch assays, this production is magnified under conditions favouring intracellular nitrite accumulation, but repressed when nitrate reductase (NR) activity is inhibited. Read more
Carbonate mineral saturation states in the East China Sea: present conditions and future scenarios Biogeosciences DOI 10.5194/bg-10-6453-2013 11 October 2013 To assess the impact of rising atmospheric CO2 and eutrophication on the carbonate chemistry of the East China Sea shelf waters, saturation states (Ω) for two important biologically relevant carbonate minerals were calculated throughout the water column. Read more
A novel salinity proxy based on Na incorporation into foraminiferal calcite Biogeosciences DOI 10.5194/bg-10-6375-2013 9 October 2013 This study investigates the impact of salinity on foraminiferal Na/Ca values by laser ablation ICP-MS analyses of specimens of the benthic foraminifer Ammonia tepida cultured at a range of salinities (30.0–38.6). Read more
Remote sensing of LAI, chlorophyll and leaf nitrogen pools of crop- and grasslands in five European landscapes Biogeosciences DOI 10.5194/bg-10-6279-2013 7 October 2013 The purpose of this study is to use field-based and satellite remote-sensing-based methods to assess leaf nitrogen pools in five diverse European agricultural landscapes located in Denmark, Scotland (United Kingdom), Poland, the Netherlands and Italy. LAI, chlorophyll and leaf nitrogen pools of crop- and grasslands in five European landscapes">Read more
