scholarly journals Life History of Lepidostoma hirtum in an Iberian Stream and its Role in Organic Matter Processing

Hydrobiologia ◽  
2006 ◽  
Vol 559 (1) ◽  
pp. 183-192 ◽  
Author(s):  
H. V. S. Azevedo-Pereira ◽  
M. A. S. Graça ◽  
J. M. González
1925 ◽  
Vol 44 ◽  
pp. 153-167
Author(s):  
David Ellis

The sulphur bacteria are found in shallow waters, both marine and fresh, and play an active part in the decomposition of animal and vegetable matter. They require for their full development an abundant supply of oxygen and of sulphuretted hydrogen. They do not thrive unless the water is periodically renewed, or else is so shallow that oxygen is obtainable to a fairly large extent from the atmosphere. When the oxygen is used up their development rapidly comes to an end, and in some cases, as is described below, the organisms disappear completely. They derive their supply of sulphuretted hydrogen from the decomposition of the protein molecule of vegetable and animal matter. Usually a growth of sulphur bacteria is visible to the naked eye as a greyish or reddish mantle covering the surface of a mass of decomposing organic matter. If, for some reason or other, the supply of oxygen is not plentiful at the bottom of the pool, the mass of growth leaves the surface of the decomposing matter and moves nearer the surface of the water.


1977 ◽  
Vol 55 (1) ◽  
pp. 161-168 ◽  
Author(s):  
Graham R. Daborn

The life history of B. mackini was studied in a large argillotrophic lake during 1970–1972. Hatching began immediately after spring thaw and was terminated by rising salinity 10 days to 2 weeks later. Growth rates reached maxima of 1 mm/day at 4 weeks of age and then declined as mean size approached 22–23 mm at 7–8 weeks. Clutch sizes varied as a function of female length. Maximum biomass of 580 mg dry weight/m2 (2700 cal/m2) was reached in late May, of which 3.9% per day was consumed by B. gigas. Source of the energy is presumed to be a bacteria – organic matter complex associated with suspended particles. Life cycle details are compared with other fairy shrimp species and the role of B. mackini in the community is discussed.


2013 ◽  
Vol 24 (1) ◽  
pp. 29-34 ◽  
Author(s):  
Bo Tiziano ◽  
Manuel Jesús López-Rodríguez ◽  
Alessandro Mogni ◽  
Josè Manuel Tierno de Figueroa ◽  
Stefano Fenoglio

The biology of stoneflies from Apennine mountain system is little known. In the present study, we provide information on the life cycle, secondary production, nymphal feeding and flight period of <i>Capnia bifrons</i> (Newman, 1838) in the Albedosa creek (NW Italy). At this study site, the species has a univoltine life cy- cle, with a relatively short and fast nymphal development period and high annual secondary production. Nymphs feed mainly on detritus but incorporate also other food items in their diet, such as coarse particulate organic matter and fungi. Ontogenetic shift from collector-gatherer to shredder habits is detected. Emer- gence is in February–April, slightly late compared to northern populations.


2008 ◽  
Vol 19 (4) ◽  
pp. 228-231 ◽  
Author(s):  
Stefano Fenoglio ◽  
Tiziano Bo ◽  
Jesus López-Rodríguez ◽  
José Tierno de Figueroa

Some aspects of the life history of a population of Brachyptera risi were investigated in a North Apennine stream and compared with previously studied European populations. In our study area, this species showed a univoltine fast seasonal life cycle. Nymphs were present from January to the beginning of May, probably spending the rest of the year mainly in egg diapause. Fine particulate organic matter was the principal component of the diet, while diatoms and other algae were also found in the guts. This finding suggests the existence of greater trophic plasticity of the species. Individuals of this population act as gatherer-collectors but not as scrapers as usually pointed out for other European populations. We also detected considerable amounts of animal matter in the gut contents. The density of B. risi nymphs in the study area was very variable during the study period, ranging from 0 to 2,348 ind/m2.


1990 ◽  
Vol 28 (1) ◽  
pp. 39 ◽  
Author(s):  
S H Lee ◽  
J Y Chai ◽  
S T Hong ◽  
W M Sohn
Keyword(s):  

Derrida Today ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 72-94
Author(s):  
Bernard Stiegler

These lectures outline the project of a general organology, which is to say an account of life when it is no longer just biological but technical, or when it involves not just organic matter but organized inorganic matter. This organology is also shown to require a modified Simondonian account of the shift from vital individuation to a three-stranded process of psychic, collective and technical individuation. Furthermore, such an approach involves extending the Derridean reading of Socrates's discussion of writing as a pharmakon, so that it becomes a more general account of the pharmacological character of retention and protention. By going back to Leroi-Gourhan, we can recognize that this also means pursuing the history of retentional modifications unfolding in the course of the history of what, with Lotka, can also be called exosomatization. It is thus a question of how exteriorization can, today, in an epoch when it becomes digital, and in an epoch that produces vast amounts of entropy at the thermodynamic, biological and noetic levels, still possibly produce new forms of interiorization, that is, new forms of thought, care and desire, amounting to so many chances to struggle against the planetary-scale pharmacological crisis with which we are currently afflicted.


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