The low-productivity South Pacific Gyre (SPG) is Earth's largest oceanic province. Its sediment accumulates extraordinarily slowly (0.1-1 m per million years). This sediment contains a living community that is characterized by very low biomass and very low metabolic activity. At every depth in cored SPG sediment, mean cell abundances are 3 to 4 orders of magnitude lower than at the same depths ...

We tested the ability of sporophytes of a small kelp, Ecklonia radiata (C. Agardh) J. Agardh, to adjust their photosynthesis, respiration, and cellular processes to increasingly warm ocean climates along a latitudinal gradient in ocean temperature (∼4°C). Tissue concentrations of pigment and nutrients decreased with increasing ocean temperature. Concurrently, a number of gradual changes in the ...

Microbiopsies of human skeletal muscle are increasingly adopted by physiologists for a variety of experimental assays given the reduced invasiveness of this procedure compared to the classic Bergstrom percutaneous biopsy technique. However, a recent report demonstrated lower mitochondrial respiration in saponin-permeabilized muscle fiber bundles (PmFB) prepared from microbiopsies vs. Bergstrom ...

Alveolar partial pressure of carbon dioxide (PACO2) and alveolar partial pressure of oxygen (PAO2) oscillate at the frequency of respiration and the oscillations persist into the arterial blood as oscillations of arterial partial pressure of carbon dioxide (PaCO2) and arterial partial pressure of oxygen (PaO2). Arterial chemoreceptors respond quickly enough to changes in PaCO2 and PaO2 for the ...

INCLÁN, R., GRAU, J. M., DANIEL DE LA TORRE , LOPEZ, M.: Soil CO2 efflux and its spatial and temporal variations in a Mediterranean Pinus sylvestris L. forest in central Spain. Lesn. Čas. – Forestry Journal, 52(1–2): 3–7, 2006, 1 fig., tab. 1, ref. 11. Original paper. ISSN 0323–1046 The main factors influencing spatial and temporal variations in soil respiration were investigated in 5 sampling ...

This lecture reviews the past (since 1964 when the International Biological Program began) and the future of our understanding of terrestrial carbon fluxes with focus on pho-tosynthesis, respiration, primary-, ecosystem-, and biome-productivity. Photosynthetic capacity is related to the nitrogen concentration of leaves, but the capacity is only rarely reached under field conditions. Average rat...

Measurement depth effects on the apparent temperature sensitivity of soil respiration in field studies A. Graf, L. Weihermüller, J. A. Huisman, M. Herbst, J. Bauer, and H. Vereecken Forschungszentrum Jülich, Agrosphere Institute (ICG-4), Institute for Chemistry and Dynamics of the Geosphere, 52425 Jülich, Germany Received: 7 April 2008 – Accepted: 7 April 2008 – Published: 6 May 2008 Correspond...

In the next few decades, climate of the Amazon basin is expected to change, as a result of deforestation and rising temperatures, which may lead to feedback mechanisms in carbon (C) cycling that are presently unknown. Here, we report how a throughfall exclusion (TFE) experiment affected soil carbon dioxide (CO2) production in a deeply weathered sandy Oxisol of Caxiuanã (Eastern Amazon). Over th...

The thinning of loblolly pine plantations has a great potential to influence the fluxes and storage of carbon within managed stands. This study looked at the effects of thinning on aboveground carbon and mineral soil carbon storage, 14-years after the thinning of an 8-year-old loblolly pine plantation on the piedmont of Virginia. The study also examined soil respiration for one year following t...