This research conducted to evaluate spatial pattern of some biological variables (mean diameter, density, richness index and biodiversity index) of forest by linear regression models using terrain analysis in the Kheiroud-Kenar forest located at the Nowshahr, north of Iran. To obtain these parameters, sampling was performed on a systematic grid (250× 400 m) in 193 plots with one ha area. Densit...

1. Land-use studies are challenging because of the difficulty of finding catchments that can be used as replicates and because land-use effects may be obscured by sources of variance acting over spatial scales smaller than the catchment. To determine the extent to which land-use effects on stream ecosystems are scale dependent, we designed a wholecatchment study of six matched pairs (pasture ve...

the objective of this study was to diagnose integrative ecological health of an urban stream,which is located in the asian temperate region. the research approach was primarily based on the index ofbiological integrity (ibi) using fish assemblage and a qualitative habitat evaluation index (qhei). and these indexes were compared with long-term conventional chemical dataset during 1996-2005. for ...

In this study, the momentum and energy equations of laminar flow of a non-Newtonian fluid are solved in an axisymmetric porous channel using the least square and Galerkin methods. The bottom plate is heated by an external hot gas, and a coolant fluid is injected into the channel from the upper plate. The arising nonlinear coupled partial differential equations are reduced to a set of coupled no...

Digital Elevation Models (DEMs) are used to estimate different morphologies, analysis of river profile, delineating drainage basin and drainage pattern associated with lithological and structural changes. The study area is Maroon River located in Khuzestan Province, Iran. In this study geomorphometric analysis based on DEM carried out to understand Maroon river uplift rate and tectonic- erosion...

study area is located in the central kopehdagh north of bojnurd and shirvan cities, between kakli and raz villages. aim of this research is separating high activity area from low activity. in this study, in order to evaluate rate of tectonic activity, stream length-gradient index (sl), ratio of valley floor width to valley height (vf), transverse topographic system (t), hypsometric integral (hi...

1. introduction floods are among earth's most common and most destructive natural hazards. floods create geomorphic hazards via changes in sediment transport and channel configuration (e.g. channel width, lateral migration, planform changes, etc). in this context, floodplain zoning and its application in spatial planning is important in non- structural measures in order to reducing flood damage...

Cave levels, passages found at similar elevations and formed during the same constant stream base level event, reveal information about paleoclimates and karst geomorphology. The investigation presented here examines how Stream Power Index (SPI) relates to cave levels. The study area, Carter Caves State Resort Park (CCSRP), is a fluviokarst system in northeastern Kentucky containing multiple ca...