APPLICATION OF INFILTRATION THEORY FOR THE DETERMINATION OF EXCESS RAINFALL HYETOGRAPH1

ABSTRACT: The purpose of this paper is to show through the use of numerical examples that modern infiltration theory can be used in everyday hydrologic practice. The actual use of four methods of calculation of infiltration rates and of excess rainfall rates is demonstrated for the case when simultaneous data of rainfall and stream flow are available for a watershed. The four methods are: (1) the well known Π-index method, (2) the traditional Horton's infiltration capacity formula, (3) the less traditional Green and Ampt infiltration capacity formula, and (4) a ponding time approach. It is recommended that hydrologists become at least familiar with the numerical procedures involved in the ponding time and postponding infiltration approach. This approach, though not flawless, should be preferred to the other three methods if use of the other three is at all considered.     

Identification of Four Distinct Subunit Types in the Unique 6×6 Hemocyanin of the Centipede Scutigera coleoptrata

 We isolated 6×6 hemocyanin, dissociated it into subunits, and examined it by electron microscopy. The subunits were separated by native polyacrylamide gel electrophoresis (PAGE), sodium dodecyl sulfate PAGE, and crossed immunoelectrophoresis. Single subunits were isolated by gel cutting from native PAGE and identified as hemocyanin by measuring their ultraviolet spectrum. A total of four distinct hemocyanin subunits were identified, and the subunit pattern of the three electrophoresis systems assigned to each other. The relative proportion of subunits a:b:c:d were 2 : 2 :>: 1 as determined by densitometry. Presumably, c and d act as linkers between hexamers. Received: 9 November 1998 / Accepted in revised form: 14 April 1999     

The role of two distinct subunit types in the architecture of keyhole limpet hemocyanin (KLH)

The Science of Nature -     

Hochwasser 2002

In August 2002, highly contaminated areas in the region of Bitterfeld, e.g. the floodplain of the creek Spittelwasser, as well as the adjacent regions of Jeßnitz and Raguhn, were submerged by the river Mulde. An input of mobilized contaminated sediments in residential areas was the matter of concern. The objective of the present study was to estimate the pollutants load on the basis of chemical and biological data and identify the sources of pollutants. Deposited sludge and flood water samples were assessed on the basis of biological and chemical analyses and in comparison with administrative reference values. The pollution of the investigated sites was rather heterogeneous. At several sites, tolerance limits of the German Klärschlammverordnung or the Bundesbodenschutzverordnung were clearly exceeded, e.g. for Pb, As and HCH. Organic extracts exhibited significant effects in several biotests. This may be relevant with respect to direct particle uptake via ingestion or respiration. Pollution patterns for heavy metals as well as for organic pollutants differed significantly from the pattern found in the Spittelwasser flood plain before the inundation, which is in contrast to the initial hypothesis of a possible transport of contaminated Spittelwasser sediments into residential areas. Interestingly, a correlation of chemical load and the overall biological effect could be shown. From the viewpoint of the precautionary principle, the identification of the compounds exerting toxic effects and of the respective pollutant sources would be desirable.     

Yolk testosterone organizes behavior and male plumage coloration in house sparrows (<Emphasis Type="Italic">Passer domesticus</Emphasis>)

Vertebrate eggs contain maternal steroid hormones in their yolks; and in avian species the concentration of these steroids vary within and among clutches. The organizational actions of these variable doses of maternal steroids in the avian egg, analogous to those regulating the development of sexually dimorphic traits, are little explored. In this study, we examined the organizational effects of yolk testosterone in the house sparrow, Passer domesticus, a sexually dichromatic passerine bird in which males are characterized by the presence of a throat patch or badge of black feathers that varies in size among males. We injected a physiological dose of testosterone or vehicle into eggs in the field, removed nestlings, and hand-raised them in the laboratory. At 5 months of age, we investigated treatment effects on plumage and behavior. Males that hatched from testosterone-injected eggs developed a larger badge than males that hatched from vehicle-injected (control) eggs. However, testosterone did not induce the expression of a badge in females. In staged dyadic encounters, both males and females hatched from testosterone-injected eggs were more successful at obtaining and defending a food source than individuals of the same sex hatched from control eggs. The results suggest that variable concentrations of maternal testosterone in the eggs of the house sparrow organize the expression of a plumage trait in males and behavior in both sexes.Communicated by J. Graves     

Experimental study of a positive surge. Part 1: basic flow patterns and wave attenuation

A positive surge results from a sudden change in flow that increases the depth. It is the unsteady flow analogy of the stationary hydraulic jump and a geophysical application is the tidal bore. Positive surges are commonly studied using the method of characteristics and the Saint-Venant equations. The article presents the results from new experimental investigations conducted in a large rectangular channel. Detailed unsteady velocity measurements were performed with a high temporal resolution using acoustic Doppler velocimetry and non-intrusive free-surface measurement devices. Several experiments were conducted with the same initial discharge (Q = 0.060 m³/s) and six different gate openings after closure resulting in both non-breaking undular and breaking bores. The analysis of undular surges revealed wave amplitude attenuation with increasing distance of surge propagation were in agreement with Ippen and Kulin theory. Also, undular wave period and wave length data were relatively close to the values predicted by the wave dispersion theory for gravity waves in intermediate water depths.