The paper represents a comparative cytogenetic analysis of three populations of Hypostomus regani in Brazil.Two populations belong to the Upper Paraná River Basin and the third one, the karyotype of which is described for the first time, was probably introduced into the São Francisco River Basin through transposition from the Piumhi River. Karyotype features of populations of Hypostomus regani ...

Transtensional basins have formed along the Pacific-North America plate boundary in the Gulf of California and Salton Trough region during Late Cenozoic time. Axial basins occupy a 50–60 kmwide belt along themainplate boundary, and change from sedimentstarved oceanic spreading centers in the south that are oriented perpendicular to long NW-striking transform faults, to oblique N-trending pull-a...

Fish species of the Zungaro genus (Siluriformes, Pimelodidae) are amongst the largest migratory fish in Latin America and have considerable economic importance for commercial fishing in Brazil. However, natural populations of this large catfish are experiencing a severe decline. There are significant taxonomical inconsistencies for this fish. Two geographically separated species of the fi...

The new model ArcEGMO-URBAN aims at deterministic and spatiotemporal modelling of water, nitrogen and phosphorus fluxes from all urbanised areas of a river basin considering all potential sources. Pollution loads are calculated for discrete urban patches and balanced on the level of hydrological subbasins. Modelling results can be defined by the user of any level of spatial and/or temporal aggr...

The hydrological response of Swiss river basins to the 2003 European summer heatwave was evaluated by a combined analysis of historical discharge records and specific applications of distributed hydrological modeling. In the summer of 2003, the discharge from headwater streams of the Swiss Central Plateau was only 40%–60% of the longterm average. For alpine basins runoff was about 60%–80% of th...

Boundaries between the various topographic, geologic, and socio-political entities that span the Earth’s continental surfaces are determined by a myriad of complexly interrelated natural and/or cultural factors. Areas of large river basins, of lithologic units on geologic maps, and of nations exhibit size frequency distributions that are closely approximated by density functions in which diamet...

To predict erosion rates throughout the Andes, we conducted a multiple regression analysis of the sediment discharge from 47 drainage basins in the Bolivian Andes and various topographic, climatologic, and geologic parameters. These mountainous basins are typically large (17–81,000 km; km), often have decades of measurement mean p 11,000 data on daily water and sediment discharge, and display a...

We applied multiple geochemical tracers (87Sr/86Sr, [Sr], d13C, and d18O) to waters and carbonates of the lower Colorado River system to evaluate its paleohydrology over the past 12 Ma. Modern springs in Grand Canyon reflect mixing of deeply derived (endogenic) fluids with meteoric (epigenic) recharge. Travertine (<1 Ma) and speleothems (2–4 Ma) yield 87Sr/86Sr and d13C and d18O values that ove...

malaysian mahseer, tor douronensis, locally known as “kelah” in peninsular malaysia or semah in sarawak is one of the important mahseers used for food as well as the aquarium industry and game fishing. this species is endemic to malaysian borneo river basins. the wild stocks of t. douronensis have declined substantially in recent years, due to over exploitation, pollution and illegal fishing pr...

Blastomyces dermatitidis and Blastomyces gilchristii are dimorphic fungal pathogens that cause serious pulmonary and systemic infections in humans. Although their natural habitat is in the environment, little is known about their specific ecologic niche(s). Here, we analyzed 25 microsatellite loci from 169 strains collected from various regions throughout their known endemic range in North Amer...