The aim of this study was to assess the invasion risk of freshwater habitats and determine the environmental variables that are most favorable for the establishment of alien amphipods, isopods, gastropods, and bivalves. A total of 981 sites located in streams and rivers in Germany. Therefore we analyzed presence-absence data of alien and indigenous amphipods, isopods, gastropods, and bivalves f...

a large number of authors have studied to find out how to control scouring around a pier along direct stream. the objective of this research is then to study a scour pattern around such piers on curves rivers due to the fact that there may be a difference between a flow pattern on a direct line and the meander. thus, this study tries to check whether the use of cable and collar alone and in a c...

We analysed stable carbon and nitrogen isotopic ratios of dissolved inorganic carbon (DIC), plants, detritus and fishes to estimate the relative importance of dominant production sources supporting food webs of four Venezuelan rivers with divergent geochemical and watershed characteristics. Based on samples taken during the dry season at each site, fishes from two nutrient-poor, blackwater rive...

the fish assemblage and diversity in relation to water quality of three coastal rivers sita, swarna and varahi of udupi district, karnataka, india was studied. 71 species representing 7 orders, 20 families and 41 genera were recorded from 21 sites along the three rivers. species composition varied longitudinally in relation to the environmental factors of the habitat. the downstream change in t...

The chemical and microbiological properties of Lebanese perennial coastal rivers were studied during the dry season extending from July to September 2004. The results indicate significant levels of pollution in all eight rivers. Although many physical and chemical variables were within WHO guidelines for drinking water, coliform levels were unacceptably high indicating pollution from untreated ...

Euclidean distance matrix completion problem aims at reconstructing the low dimensional geometry structure of nodes given only a few pairwise distances between nodes [1]. This problem arises in many applications including networks and machine learning where much information of points is laking. For instance, in sensor networks, due to the constraints of energy and communication radius, sensor n...

For slowly varying fields the vacuum functional of a quantum field theory may be expanded in terms of local functionals. This expansion satisfies its own form of the Schrödinger equation from which the expansion coefficents can be found. For scalar field theory in 1+1 dimensions we show that this approach correctly reproduces the short-distance properties as contained in the counter-terms. We a...

The fast-start (acceleration) performance of seven groups of rainbow trout from 9-6 to 38-7 cm total length was measured in response to d.c. electric shock stimuli. Two fast-start kinematic patterns, L- and S-start were observed. In L-starts the body was bent into an L or U shape and a recoil turn normally accompanied acceleration. Free manoeuvre was not possible in L-starts without loss of spe...

Arid zones have been affected during the quaternary by a large hydrological and climate variability. This change of processes has shaped the landscape leaving the signature of former paleodrainage and sedimentological features. Using the radar SAR images matched with the detailed topography, obtained from the SRTM (Shuttle Radar Topography Mission) data and ERS interferometry, it is possible to...