Studies on the Biology and Chemistry of the Gulf of Maine

Gran, H. H.

doi:10.2307/1537227

Cited by 49 publications

(14 citation statements)

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“…Apparently, they were confirming the same working hypothesis of GRAN (1933) and later on BRAND, SUNDA and GUILLARD (1983), SUNDA et al ( 1991 ) as well as BRAND ( 1991 ). In the same time MENZEL and SPAETH(1962a) reported soluble and particulateFeconcentrations at ~ 1 gg L l in the Sargasso Sea, in another paper contemplated vitamin B-12 (i.e.…”

Section: Iron In the Marinesupporting

confidence: 74%

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von Liebig's law of the minimum and plankton ecology (1899–1991)

Baar

1994

Progress in Oceanography

237

132

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-The Law of the Minimum was originally formulated by Justus yon Liebig, as one of the 50 interlinked laws concerned with agriculture. The original writings ofJ. von Liebig often were misinterpreted by his successors. BRAt, rOT (1899) took this one law out of its context and proposed that limitation by nitrogen is a dominant factor in plankton ecology, far beyond its original application to agriculture. This was opposed by NAmANSOrn~ (1908) who suggested instead a dynamic balance of growth and loss terms. Towards validating, or eventually falsifying Brandt's hypothesis, Atkins, Harvey, Cooper and others developed the chemical methods necessary for re-defining ocean nutrient cycling and growth limitation. The major exception to these modem perspectives was the Antarctic Paradox of higla nutrients and low chlorophyll which inspired Gran, Atkins, Harvey and Cooper to pioneer the concept of iron limitation. An exhaustive overview is given of efforts to define Fe in seawater and its controlling effect on in situ plankton growth, for the 1920-1984 period. Somewhat parallel work in the laboratory on single species of algae in chelation-controlled mediahas provided much insight, but is sketched only briefly. Martin and contemporaries developed the chemical methods necessary for defming the ocean chemistry of Fe and its role for in situ growth. These developments are sketched for the 1982-1991 period. Once again the Law of the Minimum and associated bold hypotheses served, albeit briefly, to bring a nutrient element in the forefront of research. This, and the recent awareness of CO 2 as rate limiting factor, underline the conclusion that advances in sciences often hinge on advances in technology, confirming Kta-~ (1962). In this case the new analytical techniques developed by Atkins, Harvey, Cooper, Martin and their associates have proven revolutionary for plankton ecology. Some observations in plankton ecology may be reminiscent of the agricultural Law of the Minimum, but this would not warrant its direct application, beyond its original context and agriculture, to plankton ecology. Rather the net rate of increase ofphytoplankton is the dynamic balance of multiple growth and loss terms, together also determining the biomass at given time and space. 347

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Section: Iron In the Marinesupporting

confidence: 74%

“…Meanwhile GRAN (1933) was working in the Gul fofMaine on boardAtlantis, the elegant vessel of the Woods Hole Oceanographic Institution. Upon advice of Waksman, the effect of synthetic ferri-ligno-protein (as proxy of natural humates) was studied, also with additional MnC12 added.…”

Section: The Antarctic Paradox (Ruud and Gran)mentioning

confidence: 99%

von Liebig's law of the minimum and plankton ecology (1899–1991)

Baar

1994

Progress in Oceanography

237

132

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“…However, the bacterial counts showed that a greater development of bacteria took place in the presence of the diatoms than in their absence. This confirms the previous observations of Gran (1933) that there is a certain parallelism between the development of diatoms and bacteria in sea . water.…”

Section: Methodssupporting

confidence: 93%

Relation of Bacteria to Diatoms In Sea Water

Waksman

Butler

1937

J. Mar. Biol. Ass.

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The functions of the two major constituent groups of the phytoplankton, namely, the diatoms and the bacteria, are supplementary to one another in the cycle of life in the sea: the diatoms synthesize organic matter from the simple chemical substances produced in the decomposition or mineralization of organic matter in the sea by the bacteria. Although the general aspects of the activities of these two groups of organisms are fairly well known, their mutual interrelationships still remain to be determined. The following studies were carried out in an attempt to elucidate this important problem. METHODSFour methods were used in these investigations: (I) Oxygen consumption in sea water enriched with diatom material; the oxygen being determined by a modification of the Winkler method. (2) Nitrogen transformation in the water, as a result of bacterial activities; the nitrogen being determined either directly as ammonia or indirectly, namely by an increase in oxygen consumption as a result of addition of glucose to the water; it had been previously found (Waksman & Carey, I935) that the rate of glucose decomposition in sea water is controlled by the available nitrogen in the water. (3) Regeneration of the phosphorus, the latter being determined by the Atkins-Deniges method. (4) Increase in bacterial numbers, as measured by the plate method.In most of the previous experiments on decomposition of organic matter in sea water (Waksman, Carey & Reuszer, I933), excessive amounts of plankton material were added to the water. This resulted in appreciable changes in the aqueous medium, particularly the rapid consumption of the oxygen, whereby the system became changed from a purely aerobic to a distinctly anaerobic one. In the following experiments, mixed and pure plankton were added in concentrations not greatly in excess of those frequently found in natural sea water. Studies were also made of the transformation of marine plankton in the same vessel in which it had been synthesized.

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“…Internal nitrate pools up to 100 mM have been documented (Villareal & Lipschultz 1995), and deep populations with seasonal descent and ascent are noted in the Mediterranean Sea (Wiebe et al 1974). Abundance ranges from ~10 -3 cells m -3 (Wiebe et al 1974) to 340 cells L -1 (Gran 1933). Halosphaera is representative of a number of species that reproduce by phycoma and swarmer formation, including members of the genus Pterosperma. )…”

Section: Other Vertically Migrating Phytoplankton Taxa: Life History mentioning

confidence: 99%

Upward nitrate transport by phytoplankton in oceanic waters: balancing nutrient budgets in oligotrophic seas

Villareal

Pilskaln

Montoya

et al. 2014

Preprint

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In oceanic gyres, primary producers are numerically dominated by small (1-5 µm diameter) pro-and eukaryotic cells that primarily utilize recycled nutrients produced by rapid grazing turnover in a highly efficient microbial loop. Continuous losses of nitrogen to depth by sinking, either as single cells, aggregates or fecal pellets, are balanced by both nitrate inputs at the base of the euphotic zone and nitrogen-fixation. This input of N (new nitrogen) to balance export losses (the biological pump) is a fundamental aspect of nitrogen cycling and central to understanding carbon fluxes in the ocean. In the Pacific Ocean, detailed nitrogen budgets at the time-series station HOT require upward transport of nitrate from the nutricline (80-100 m) into the surface layer (~0-40 m) to balance productivity and export needs. However, concentration gradients are negligible and cannot support the fluxes. Physical processes can inject nitrate into the base of the euphotic zone, but the mechanisms for transporting this nitrate into the surface layer across many 10s of m in highly stratified systems are unknown.In these seas, vertical migration by the very largest 10 2 -10 3 µm diameter) phytoplankton is common as a survival strategy to obtain nitrogen from sub-euphotic zone depths. This vertical migration is driven by buoyancy changes rather than by flagellated movement and can provide upward nitrogen transport as nitrate (mM concentrations) in the cells. However, the contribution of vertical migration to nitrate transport has been difficult to quantify over the required basin scales. In this study, we use towed optical systems and isotopic tracers to PrePrintsIntroduction Nitrogen in the euphotic zone of the open sea has long been recognized to partition into two distinct pools of availability (Dugdale & Goering 1967). New nitrogen represents introduction of N from outside the euphotic zone, either in the form of deep NO 3 -or nitrogenfixation, while regenerated N results from consumption and remineralization of dissolved or particulate N (Dugdale & Goering 1967). While regenerated N dominates the total phytoplankton uptake, new N is critical to balance losses due to vertical fluxes and is linked to total system productivity (Eppley & Peterson 1979). This has been expressed as the f ratio where 'f' = new/total N uptake and ranges from 0-1. On longer time scales, new N input must balance sedimentary losses or the system will experience net losses of nitrogen (Eppley & Peterson 1979). The surface waters of the open ocean are considered low 'f' ratio environments: N and P often occur at nM concentrations, and ammonium is the dominant form taken up by phytoplankton (Lipschultz et al. 1996;Raimbault et al. 2008;Wu et al. 2000). The f ratio increases in the light-limited lower depths of the euphotic zone due to the increased availability of nitrate at the nutricline, thus creating what has been recognized as a two-layered structure (Goldman 1988). This general pattern can be modified in regions of low iron input, where iron ava...

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Studies on the Biology and Chemistry of the Gulf of Maine

Cited by 49 publications

References 0 publications

von Liebig's law of the minimum and plankton ecology (1899–1991)

von Liebig's law of the minimum and plankton ecology (1899–1991)

Relation of Bacteria to Diatoms In Sea Water

Upward nitrate transport by phytoplankton in oceanic waters: balancing nutrient budgets in oligotrophic seas

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