Photosynthesis aquatic

Tsuzuki M, Miyachi S. 1989. The functions of carbonic anhydrase in aquatic photosynthesis. Aquatic Botany 34 85-104. 

Precipitation Reactions. A change in the pH of a natural water may result in the precipitation from solution of those species that are at or near saturation if one of the precipitating species enters into acid-base reactions. The classical example is the photosynthetic precipitation of calcium carbonate. During photosynthesis, aquatic plants may remove sufficient C02 to raise the pH to the value at which the concentration of carbonate times that of calcium exceeds the solubility product for calcium carbonate. If nucleation occurs, calcium carbonate will be precipitated. 

Rysgaard, S., Risgaard-Petersen, N., and Sloth, N. P. (1996). Nitrification, denitrification, and nitrate ammonification in sediments of two coastal lagoons in Southern France. Hydrobiol. 329, 133—141. Sand-Jensen, K. (1977). Effects of epiphytes on eelgrass photosynthesis. Aquat. Bot. 3, 55—63. Sand-Jensen, K., and Borum, J. (1991). Interactions among phytoplankton, periphyton, and macrophytes in temperate freshwaters and estuaries. Aquat. Bot. 41, 137—175. 

On Earth, carbon dioxide was removed from the atmosphere over long periods of time, primarily as the result of the formation of carbonate rocks in the Earth s crust, a process catalyzed by water. As living organisms appeared and evolved on Earth s surface, they contributed to the removal of carbon dioxide—plants through the process of photosynthesis, aquatic animals by incorporating it into their shells. In addition, Earth s average annual temperature was sufficient to allow water vapor to condense into liquid water,... 

A relatively small number of studies have reported on the effects of cumene on plants, fish, and other organisms. Studies of the effects of cumene on fresh and saltwater fish indicate the lowest reported toxic concentration (LC q) for fishes was 20 to 30 mg/L (18). The solubiUty of cumene is about 50 mg/L (19). Among invertebrates, the lowest reported concentration that was toxic to test organisms was 0.012 mg/L after 18 hours (20). The only available data on the effect of cumene on aquatic plants indicate that the photosynthesis of several species was inhibited at concentrations from 9 to 21 mg/L (19). 

Rate constants for a large number of atmospheric reactions have been tabulated by Baulch et al. (1982, 1984) and Atkinson and Lloyd (1984). Reactions for the atmosphere as a whole and for cases involving aquatic systems, soils, and surface systems are often parameterized by the methods of Chapter 4. That is, the rate is taken to be a linear function or a power of some limiting reactant - often the compound of interest. As an example, the global uptake of CO2 by photosynthesis is often represented in the empirical form d[C02]/df = —fc[C02] ". Rates of reactions on solid surfaces tend to be much more complicated than gas phase reactions, but have been examined in selected cases for solids suspended in air, water, or in sediments. 

These high levels were sporadic and transitory. However, some of them were high enough to have caused phytotoxicity, and more work needs to be done to establish whether herbicides are having adverse effects upon populations of aquatic plants in areas highlighted in this study. It should also be borne in mind that there may have been additive or synergistic effects caused by the combinations of herbicides found in these samples. For example, urea herbicides such as diuron and chlortoluron act upon photosynthesis by a common mechanism, so it seems likely that any effects upon aquatic plants will be additive. Similarly, simazine and atrazine share a common mechanism of action. 

Nonpolar gases are only slightly soluble in water. For example, water in contact with the Earth s atmosphere contains O2 at a concentration of only about 2.5 x 10 M and CO2 at about 1 x 10 M. Nevertheless, these small concentrations are essential for aquatic life. Fish and other aquatic animals use their gills to extract O2 dissolved in water, and unless that oxygen is replenished, these species die. Submerged green plants carry out photosynthesis using dissolved carbon dioxide, which also must be replenished for these plants to survive. 

Three processes that take place in living organisms - respiration in animals and plants, photosynthesis only in plants, and the precipitation of solids by some aquatic animals - have altered the primeval composition of the outer solid, liquid, and gaseous layers of the earth. Respiration consumes oxygen from the atmosphere and creates carbon dioxide. Photosynthesis, which does the opposite (consumes carbon dioxide and releases oxygen), has... 

Sensitive terrestrial plants die when soil zinc levels exceed 100 mg/kg (oak and maple seedlings), and photosynthesis is inhibited in lichens at >178 mg Zn/kg DW whole plant. Sensitive terrestrial invertebrates have reduced survival when soil levels exceed 470 mg Zn/kg (earthworms), reduced growth at >300 mg Zn/kg diet (slugs), and inhibited reproduction at >1600 mg Zn/kg soil (woodlouse). The most sensitive aquatic species were adversely affected at nominal water concentrations between 10 and 25 pg Zn/L, including representative species of plants, protozoans, sponges,... 

KEYWORDS atmospheric CO2 Sink, carbonate dissolution, global water cycle, aquatic photosynthesis, organic matter storage/burial... 

Ultraviolet radiation (UVR) is a natural fraction of the solar radiation, and therefore has always influenced life in aquatic ecosystems. The development of oxygenic photosynthesis 2.5-2 J billion years ago (Holland 1984) led to drastic chemical changes in the Earth s oceans and atmosphere. The gradual increase in photosyn-thetically produced oxygen over millions of years was accompanied by a strong enrichment of it in the atmosphere, which ultimately acted as precursor for the ozone (03) layer in the stratosphere. 

Villafane VE, Sundback K, Figueroa FL, Helbing EW (2003) Photosynthesis in the aquatic environment as affected by UVR. In Helbing EW, Zagarese HE (eds) UV effects in aquatic... 

The pH of the water on the surface of a submerged soil often depends on the activity of photosynthetic organisms. Photosynthesis by aquatic plants and algae removes dissolved CO2 during the day, but at night the net respiratory activity of the organisms returns CO2 to the water and the concentration of dissolved CO2 and acidity increase ... 

Photosynthesis in phytoplankton and higher plants Chlorophyll for aquatic monitoring Marine science 61, 62... 

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