Marine Ecosystem Analysis of Gouldsboro and Dyer Bays, Maine

<p>In the early 1980s, the National Oceanic and Atmospheric Administration (NOAA) initiated an ecosystem analysis of Gouldsboro Bay in eastern Maine as part of a planned marine sanctuary. The original report to NOAA by Walter H. Adey was not published after the sanctuary concept for Maine was abandoned. Because significant human-related climatic and ecosystem changes are underway in the Gulf of Maine, that report provides valuable baseline data and is included as the Appendix to this volume. After qualitatively describing the geological, physical, chemical, and biogeographical features of Gouldsboro Bay and adjacent Dyer Bay, we quantitatively describe the principal bay ecological communities with data collected during the 1981–1983 ecosystem assessment as well as additional measurements taken within the past decade. We then undertake a comparison of the primary productivity of these bays with the Google Earth Pro polygon tool to determine component areas.</p><p><br></p><p>Benthic taxa are the dominant primary producers in both bays: rockweeds (primarily <i>Ascophyllum nodosum</i>, with <i>Fucus vesiculosus </i>secondary) in the intertidal; Irish moss (<i>Chondrus crispus</i>,<i> </i>with<i> Fucus distichus </i>secondary) as a near monoculture in the lowest intertidal (infralittoral); kelps (primarily <i>Saccharina latissima</i>,<i> Laminaria digitata</i>, and <i>Agarum clathratum</i>) in the rocky subtidal; and the angiosperm <i>Zostera marina</i> (seagrass) in soft bottom substrate. The rocky intertidal, dominated by <i>Ascophyllum</i> with a specific productivity of 10.6 kg/m²/year, provides nearly one-third of all bay productivity. Because of the proportionally greater shore length relative to area of Dyer Bay, it has 45% greater productivity for its surface area than Gouldsboro Bay. Kelp has a specific productivity value of 7.2 kg/m²/year, and <i>Zostera</i> of 1.2 kg/m²/year. The kelps provide approximately 20% of Gouldsboro Bay’s primary productivity and 35% of that of Dyer Bay. <i>Zostera</i> provides roughly 20% of total primary productivity in Gouldsboro Bay and 12% in Dyer Bay. With a primary productivity of 1.73 kg/m²/year, salt marshes provide only 3.7% (Gouldsboro) and 2.6% (Dyer) of total primary productivity. With a primary productivity of 0.06 kg/m²/year, plankton account for 23.8% of Gouldsboro Bay and 16% of Dyer Bay primary productivity.</p>

Marine Ecosystem Analysis of Gouldsboro and Dyer Bays, Maine

In the early 1980s, the National Oceanic and Atmospheric Administration (NOAA) initiated an ecosystem analysis of Gouldsboro Bay in eastern Maine as part of a planned marine sanctuary. The original report to NOAA by Walter H. Adey was not published after the sanctuary concept for Maine was abandoned. Because significant human-related climatic and ecosystem changes are underway in the Gulf of Maine, that report provides valuable baseline data and is included as the Appendix to this volume. After qualitatively describing the geological, physical, chemical, and biogeographical features of Gouldsboro Bay and adjacent Dyer Bay, we quantitatively describe the principal bay ecological communities with data collected during the 1981–1983 ecosystem assessment as well as additional measurements taken within the past decade. We then undertake a comparison of the primary productivity of these bays with the Google Earth Pro polygon tool to determine component areas. Benthic taxa are the dominant primary producers in both bays: rockweeds (primarily Ascophyllum nodosum, with Fucus vesiculosus secondary) in the intertidal; Irish moss (Chondrus crispus, with Fucus distichus secondary) as a near monoculture in the lowest intertidal (infralittoral); kelps (primarily Saccharina latissima, Laminaria digitata, and Agarum clathratum) in the rocky subtidal; and the angiosperm Zostera marina (seagrass) in soft bottom substrate. The rocky intertidal, dominated by Ascophyllum with a specific productivity of 10.6 kg/m2/year, provides nearly one-third of all bay productivity. Because of the proportionally greater shore length relative to area of Dyer Bay, it has 45% greater productivity for its surface area than Gouldsboro Bay. Kelp has a specific productivity value of 7.2 kg/m2/year, and Zostera of 1.2 kg/m2/year. The kelps provide approximately 20% of Gouldsboro Bay’s primary productivity and 35% of that of Dyer Bay. Zostera provides roughly 20% of total primary productivity in Gouldsboro Bay and 12% in Dyer Bay. With a primary productivity of 1.73 kg/m2/year, salt marshes provide only 3.7% (Gouldsboro) and 2.6% (Dyer) of total primary productivity. With a primary productivity of 0.06 kg/m2/year, plankton account for 23.8% of Gouldsboro Bay and 16% of Dyer Bay primary productivity.

Anoxygenic Photosynthesis Controls Oxygenic Photosynthesis in a Cyanobacterium from a Sulfidic Spring

ABSTRACTBefore the Earth's complete oxygenation (0.58 to 0.55 billion years [Ga] ago), the photic zone of the Proterozoic oceans was probably redox stratified, with a slightly aerobic, nutrient-limited upper layer above a light-limited layer that tended toward euxinia. In such oceans, cyanobacteria capable of both oxygenic and sulfide-driven anoxygenic photosynthesis played a fundamental role in the global carbon, oxygen, and sulfur cycle. We have isolated a cyanobacterium,Pseudanabaenastrain FS39, in which this versatility is still conserved, and we show that the transition between the two photosynthetic modes follows a surprisingly simple kinetic regulation controlled by this organism's affinity for H2S. Specifically, oxygenic photosynthesis is performed in addition to anoxygenic photosynthesis only when H2S becomes limiting and its concentration decreases below a threshold that increases predictably with the available ambient light. The carbon-based growth rates during oxygenic and anoxygenic photosynthesis were similar. However,PseudanabaenaFS39 additionally assimilated NO3−during anoxygenic photosynthesis. Thus, the transition between anoxygenic and oxygenic photosynthesis was accompanied by a shift of the C/N ratio of the total bulk biomass. These mechanisms offer new insights into the way in which, despite nutrient limitation in the oxic photic zone in the mid-Proterozoic oceans, versatile cyanobacteria might have promoted oxygenic photosynthesis and total primary productivity, a key step that enabled the complete oxygenation of our planet and the subsequent diversification of life.

The Primary Productivity of Algae Plant of Ebinur Lake - Based on CBERS-2 Image Remote Sensing Research

This paper use the technology to process satellite image, combined with sampling and analysis, to establish the mathematical relationship model between the algal primary productivity of Ebinur Lake with the spectral information of satellite imagery, inversion of algae plant primary productivity, then get the conclusion: Based on satellite image processing technology to study the algae plant primary productivity, measured during the growth of algae plant in the total primary productivity of 99.5 t; CBERS-2 was been found that is fit for measure the primary productivity of algae plant Ebinur Lake, the characteristic of the Green band is the accuracy band; the optimal inversion model is B = 3.945-0.033G-0.005 (GR) +0.128 (G / B).

Levels of Production in the Pelagic Environment of the Strait of Georgia, British Columbia: A Review

Data have been accumulated on seasonal levels of nutrients, primary production, and zooplankton. The occurrence and abundance of larval fish in the surface layers have been reported together with an approximate estimate of the standing stock of commercially exploited fish. The results indicate that beyond local effects, the Strait of Georgia is comparable in productivity to other nearshore waters at the same latitude. The total primary productivity of the waters was found to be approximately 120 g C/m2 per year, but a high degree of areal patchiness in all production data emphasizes the necessity of basing predictions about particular subareas on knowledge specific to the subareas in question.

Extracellular products of phytoplankton photosynthesis

Following exposure in situ for periods of 3 to 24 h of samples of lake or sea waters to which 14 C-bicarbonate had been added, radioactivity was found in dissolved organic matter in the water as well as in the cells of phytoplankton. The amount in the water was between 7 and 50% of the total carbon fixed in the photic zone of the water column. This production of extracellular 14 C-labelled organic matter was found under a wide variety of conditions and with many different types of phytoplankton community. It thus seems likely that the widely used method, in which fixation of 14 C in particulate matter only is determined, under­estimates total primary productivity. The labelled organic substances in the water are probably liberated by intact photosynthesizing cells rather than by breakage of cells during filtration. Glycollic acid is likely to be one of the principal substances concerned. Over a wide range of light intensities liberation of extracellular products by a given phytoplankton population was proportional to the amount of carbon fixed in the cells, except that it tended to be relatively greater at low light intensities (< 1 kilolux) and at light intensities high enough to inhibit photosynthesis ( > 50 kilolux), when as much as 95% of the total organic 14 C might be extracellular. Population density, period of exposure to 14 C-bicarbonate and species differences also affect the extent of excretion. The implications of extensive liberation by phytoplankton of extracellular products of photosynthesis for our understanding of the trophic relationships in aquatic habitats seem to be considerable.