the effect of environmental factors on plant vegetation is different. therefore, it is necessary to evaluate role of these factors in medicinal plants growth, development and essential oil. this study was performed to investigate the effect of factors on qualitative and quantitative variations of the essential oil of verbascum songaricum in its habitats in central zagros mountains, iran in 2012...

relationships between soil factors and vegetation types in playa of damghan was investigated. six vegetationtypes including artemisia.sieberi, arundo. sp, artemisia.sieberi-peganum.harmala, alhagi.cammelerom,artemisia.sieberi-petropyron.sp, tamarix.passerinoides-halocnemum strobilaceum. one bare land was recognized inthe study area and the research was conducted within mentioned types. canopy p...

As a result of the warming observed at high latitudes, there is significant potential for the balance of ecosystem processes to change, i.e., the balance between carbon sequestration and respiration may be altered, giving rise to the release of soil carbon through elevated ecosystem respiration. Gross ecosystem productivity and ecosystem respiration vary in relation to the pattern of vegetation...

relationships between soil factors and vegetation types in playa of damghan was investigated. six vegetationtypes including artemisia.sieberi, arundo. sp, artemisia.sieberi-peganum.harmala, alhagi.cammelerom,artemisia.sieberi-petropyron.sp, tamarix.passerinoides-halocnemum strobilaceum. one bare land was recognized inthe study area and the research was conducted within mentioned types. canopy p...

Canonical community ordination comprises a collection of methods that relate species assemblages to their environment, in both observational studies and designed experiments. Canonical ordination differs from ordination sensu stricto in that species and environment data are analyzed simultaneously. Part I reviews the theory in a non-mathematical way with emphasis on new insights for the interpr...

Agglomerative clustering, Two Way Indicator Species Analysis (WINSPAN), and Detrended Correspondence Analysis (DCA) were used for the plant community analysis. Remotely sensed data was used as a surrogate in identifying and locating field sites from where floristic composition, environmental and spatial data were collected. Characteristic plant species of each community type are presented toget...

Constrained ordination methods include constrained (or canonical) correspondence analysis (CCA), redundancy analysis (RDA) and distancebased redundancy analysis (db-RDA). Constraining means that ordination only shows the community variation that can be explained by external environmental variables or constraints. This document describes the following basic concepts (1) usage of constrained ordi...

Intersite relationships among nematode communities of 18 Indiana mixed hardwood stands of varying composition, soils, physiography and past management practices were determined by community ordination techniques. All sites were sampled in April, July and October of 1968 and 1969, and ordinations were based on the number of individuals of each nematode species at each site at each sampling perio...

In this paper we report on the investigation, description and analysis of communication and co-ordination practices in software engineering projects. We argue that existing models of the software process do not adequately address the situated, day-to-day practices in which software engineers collectively engage, yet it is through these practices that effective co-ordination is achieved. Drawing...

Co-ordination is one of the central research issues in Distributed Artificial Intelligence. Most of the efforts in designing co-ordination mechanisms set out from an agent-centred point of view: they see the individual actor with its local beliefs and reasoning capabilities as the foundation of all system properties. Our thesis is that co-ordination is best modelled from an environment-centred,...