Microalgae surfaces

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. 

A few words should be said about the existence of PMT-based instruments that are developed to solve specific problems in chemi- or bioluminescence. For instance, marine laboratories have developed and improved over time a range of so-called bathyphotometers for hydrobiophysical measurements (microalgae, zooplankton in the surface waters of the sea) [7]. 

The activity of extracts against microalgae has led to the isolation of a large group of simple phenylethyl amides and various indolylethyl amides (e.g., 27, 28). We have obtained some of these compounds also from limnic bacteria, and, although their activity is low, it seems plausible that they play a role in the competition of bacteria with microalgae for free surfaces, perhaps on seaweed or other sessile organisms. 

As discussed earlier, not only does deposition of POM to the sediment surface typically vary over time in estuaries, but there are also issues of POM actively growing at the sediment-water interface, such as benthic microalgae. This is an important issue because the rate of supply of POM is assumed to be equal to the depositional flux from the water column (Berner, 1980). More details on diagenetic models addressing the surface boundary condition constraints as well as POM lability can be found in Aller (1982) and Rice and Rhoads (1989). When examining biological mixing as a one-dimensional... 

Our previous study, on the other hand, has shown that cell bodies of this microalga are of use as the partial substitute of a wood pulp paper [1], In the present study, whole kenaf pulp paper including algae obtained by the above cultivation was made and its properties were examined. It was indicated that they also could be used as an agent for surface improvement of kenaf pulp paper in addition to a partial substitute for the pulp as in the case of a paper made from wood pulp. 

Figure 3 shows the mixture of the microalgae and kenaf pulps, which indicates that the size of this microalga is extremely smaller than that of kenaf pulp fiber. The surface of microalgae-added paper looks to be smoother than that of pure kenaf-pulp paper, as shown in Fig.4. 

Figure 4. Electron micrographs of the surface of pure kenaf-pulp paper (A) and microalgae-added paper (B).The content of alga, Tetraselmis was 15%.

N. ramosissima (Bacillariophyta) (Fig. 7). The macrocolonies used the surface of C. fracta and V. cf. dichotoma as habitat, where the microalgae formed branched polymeric tubes ( curly scrub effect). Polymeric tubes of N. ramosissima were made of mucilage excreted by the diatoms [53]. As a result, we observed on top of the clay layer, a brown fur habitus covering 100% of the washed clay surface. The same brown fur spots growing directly on sediment substratum were observed... 

In November 2002, we found a large number of living microalgae species on silty sediment surfaces covering the lake bottom to depths of more than 20 m, independent of dissolved hydrogen sulphide concentration at the sediment—water... 

By June 2008 sediment surface distribution in the Western basin had strongly changed. The friable crystalline pulp covering the bottom in a layer tens of centimetres thick ( an amorphous bottom ) was observed for the first time by us in August 2004, at a depth of 38 m. In June 2008, the top of this layer began already hardly deeper than 10 m. As a result conditions of habitation for microalgae at depths of 13-15 m had been changed irreversibly. Some species disappeared or their number decreased to a level where they are not representative. The latter statement is fair for taxa, specified in the column disappeared . 

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