the present study carried out to identify neo tectonic activity of the gorgan river basin in golestan province, in north of eastern alborz range is investigated by four geomorphic indices including the stream– gradient index (sl), drainage basin asymmetry (af), reveres symmetry of topography (t) and mountain front sinuosity (smf). result from the analysis is accumulated and expressed as an in...

Controlled tile drainage (CTD) can reduce pollutant loading. The Annualized Agricultural Nonpoint Source model (AnnAGNPS version 5.2) was used to examine changes in growing season discharge, sediment, nitrogen, and phosphorus loads due to CTD for a ∼3900-km agriculturally dominated river basin in Ontario, Canada. Two tile drain depth scenarios were examined in detail to mimic tile drainage cont...

We propose, as a testable hypothesis, a basin-scale approach for interpreting the abundance of in situ produced cosmogenic isotopes, an approach which considers explicitly both the isotope and sediment flux through a drainage basin. Unlike most existing models, which are appropriate for evaluating in situ produced cosmogenic isotope abundance at discrete points on Earth’s surface, our model is ...

Introduction: Valley network systems on Mars remain the most unequivocal evidence that water carved the surface of the planet in the distant past and the climate was different than today. Most of these systems date from the Noachian [1], the p eriod of heavy bombardment which is >3.7 Ga [2], although local or regional formation seems to have continued to more recent times [3]. The discovery of ...

Alburnoides manyasensis, sp. n., is described from the Koca Stream (Lake Manyas drainage, Marmara Sea basin) in Anatolia. It is distinguished from all species of Alburnoides in Turkey and adjacent regions, Alburnoides tzanevi (Rezovska [Rezve], Istranca and Terkos streams in the western Black Sea drainage), Alburnoides cf. smyrnae (Banaz Stream, a drainage of Büyük Menderes River, Aegean Sea ba...

We present ‘bAd Calculator’, a new software developed in Visual Basic programme which can be applied for analyses of various drainage basin parameters, directional aspects, etc. The graphical user interface of bAd Calculator can be used for several applications such as determination of bearing and azimuth of linear features and their representation in rose diagram. Various drainage basin parame...

Both environmental heterogeneity and mode of dispersal may affect species co-occurrence in metacommunities. Aquatic invertebrates were sampled in 20-30 streams in each of three drainage basins, differing considerably in environmental heterogeneity. Each drainage basin was further divided into two equally sized sets of sites, again differing profoundly in environmental heterogeneity. Benthic inv...

the present study reports range extansion of moenkhausia oligolepis to the pindaré river drainage, of the mearim river basin, and itapecuru river basin, maranhão state, northeastern brazil. this species was previously known only from venezuela, guianas, and the amazon river basins. in addition, we present some meristic and morphometric data of the specimens herein examined and discuss on its di...

there is a need to analyze and map rainfall erosivity to assess soil erosion at the regional scale. the objectives of this study were to develop a regional model to estimate seasonal erosivity from seasonal rainfall data and to study temporal and spatial distribution of rainfall erosivity for the gorganrood drainage basin in the northeast of iran. six gauging stations with a high temporal resol...

there is a need to analyze and map rainfall erosivity to assess soil erosion at the regional scale. the objectives of this study were to develop a regional model to estimate seasonal erosivity from seasonal rainfall data and to study temporal and spatial distribution of rainfall erosivity for the gorganrood drainage basin in the northeast of iran. six gauging stations with a high temporal reso...