Chlorophyll biomass

The ratio of 530 450 is strongly correlated with the chlorophyll biomass in the world s oceans (i). 

However, there are interannual variations caused by the depth and rate of winter mixing. During the exceptionally cold winter of 1991/92 the 3000 m water column at the core of the Rhodes Gyre was vertically mixed from top to bottom, with homogeneous temperature and salinity profiles. At this time, there was relatively low chlorophyll biomass ( 44 mg/m2) and phytoplankton activity (Table 4.2 Edigar Yilmaz, 1996). This cannot be due to nutrient or light limitation since nutrients are present and there are phytoplankton blooms... 

The advent of easy access to the satellite-based global positioning system (GPS) and availability of off-the-shelf portable probes and rapid analyzers for a number of water quality determinants have enabled the development of systems that can be carried on small survey vessels to map water quality conditions. Rapid data acquisition is now practical using probes and sondes for measuring temperature, conductivity, turbidity, pH, and dissolved oxygen fluorometric technologies for chlorophyll biomass and phytoplankton composition flow injection and loop flow analysis for some nutrient species and acoustic Doppler-based devices for current profiling. 

Hoge, F.E., Lyon, E., Wright, P.E., Wayne, C., Swift, R.N., and Yungel, J.K. (2005). Chlorophyll biomass in the global oceans Airborne lidar retrieval using fluorescence of both chlorophyll and chromophoric dissolved organic matter. Appl. Optics, 44, 2857-2862. 

In this way, the near-linear chlorophyll-phosphorus relationship in lakes depends upon the outcome of a large number of interactive processes occurring in each one of the component systems in the model. One of the most intriguing aspects of those components is that the chlorophyll models do not need to take account of the species composition of the phytoplankton in which chlorophyll is a constituent. The development of blooms of potentially toxic cyanobacteria is associated with eutrophication and phosphorus concentration, yet it is not apparent that the yield of cyanobacterial biomass requires any more mass-specific contribution from phosphorus. The explanation for this paradox is not well understood, but it is extremely important to understand that it is a matter of dynamics. The bloom-forming cyanobacteria are among the slowest-growing and most light-sensitive members of the phytoplankton. ... 

Recently, the ocean-basin distribution of marine biomass and productivity has been estimated by satellite remote sensing. Ocean color at different wavelengths is determined and used to estimate near-surface phytoplankton chlorophyll concentration. Production is then estimated from chlorophyll using either in situ calibration relationships or from empirical functional algorithms (e.g., Platt and Sathyendranth, 1988 Field et al., 1998). Such studies reveal a tremendous amount of temporal and spatial variability in ocean biological production. 

Because of the role these algae play in the oceans biological productivity and their impacts on climate due to the removal of carbon dioxide, satellite sensors have been employed to measure the chlorophyll a contents in oceans, lakes, and seas to indicate the distribution and abundance of biomass production in these water bodies. Detection is set at the specific reflectance and absorption wavelengths of the light from the upper layer of the ocean where photosynthesis occurs. 

In a similar way, microalgal biomass on the sediment surface can be estimated by measuring the chlorophyll contents in benthic microalgae, which are single-celled microscopic plants that inhabit the top 0 to 3 cm of a sediment surface and are sometimes referred to as microphytobenthos. These organisms are the primary food resources of benthic grazers such as shellfish and numerous finfish species. 

The automated EXAMS model consists of a set of FORTRAN programs which calculates the fate, exposure and dissipation of the chemical from input environmental data such as 1) Global parameters (rainfall, irradiance, latitude), 2) Biological parameters (biomass, bacterial counts, chlorophyll), 3) Depths and in-lows, 4) Sediment characteristics, 5) Wind, 6) Evaporation, 7) Aeration, 8) Advective and turbulent interconnections, 9) Water flow, 10) Sediment flow, 11) pH and pOH, and 12) Temperature. Also characteristics of the chemical are taken into account such as hydrolysis photolysis, oxidation, biolysis, and volatility. 

Exposed for 35 days to 30, 250, or 3000 pg atrazine/L 100 pg/L, 3-4 weeks 1000 pg/L, 3-4 weeks The high concentration significantly enhanced peroxidase activity but did not affect growth or chlorophyll production (Lytle and Lytle 1998) Biomass reduction of 34% (Stevenson etal. 1982) Biomass reduction of 46% (Stevenson etal. 1982)... 

Chlorophyll a (Chi a) functions as the primary light harvesting pigment in marine oxygenic phototrophs. Even though the C Chl a ratio of photoautotrophic cells varies considerably as a function of environmental conditions and growth rate (Laws et al., 1983), measurements of Chi a have been used extensively to estimate the biomass of photoautotrophic microorganisms in the sea. 

The photoreductive synthetic process that promotes the assimilation of carbon dioxide into carbohydrates, other reduced metabolites, as well as ATP (synthesis of the latter is termed photophosphorylation). Photosynthesis is the primary mechanism for transducing solar energy into biomass, and green plants utilize chlorophyll a to capture a broad spectrum of solar radiant energy reaching the Earth s surface. Photosynthetic bacteria typically produce NADPH, the reductive energy of which is converted to ATP. 

The high concentration significantly enhanced peroxidase activity but did not affect growth or chlorophyll production (Lytle and Lytle 1998) Biomass reduction of 34% (Stevenson etal. 1982)... 

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