This research was conducted to investigate the relationships between soil(organic matter, potassium, phosphorous, sodium, fine gravel, soil texture, EC, lime,gypsum, nitrogen) and environmental (elevation, slope) factors with distribution ofvegetation types in rangelands of Sabzdasht, located in Bafgh, Yazd province at 2012. Forthis purpose, four vegetation types were selected as follows: Artem...

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...

We examined whether nitrogen (N) and carbohydrates reserves allow Veratrum album, an alpine forb, to start spring growth earlier than the neighbouring vegetation and to survive unpredictable disturbances resulting in loss of above-ground biomass. * Seasonal dynamics of plant reserves, soil N availability and vegetation growth were monitored. Veratrum album shoots were experimentally removed whe...

Practices within the Conservation Reserve Program promote planting native grasses and forbs to improve habitat for northern bobwhite (Colinus virginianus) and other wildlife. However, native grasses often become dense and stands can be invaded by undesirable plant species that reduce habitat quality. We investigated three herbicides (clethodim, glyphosate, and imazapyr) at two rates to reduce n...

Landsat 8, the most recently launched satellite of the series, promises to maintain the continuity of Landsat 7. However, in addition to subtle differences in sensor characteristics and vegetation index (VI) generation algorithms, VIs respond differently to the seasonality of the various types of vegetation cover. The purpose of this study was to elucidate the effects of these variations on VIs...

A simple matrix is a (0,1)-matrix with no repeated columns. For a (0,1)-matrix F , we say a (0,1)-matrix A avoids F (as a configuration) if there is no submatrix of A which is a row and column permutation of F . Let ‖A‖ denote the number of columns of A. We define forb(m,F ) = max{‖A‖ : A is an m-rowed simple matrix that avoids F}. Define an extremal matrix as an m-rowed simple matrix A with th...

Abstract Background Canby’s dropwort ( Oxypolis canbyi (J.M. Coult. & Rose) Fernald) was listed as federally endangered in 1986, yet the species has continued to decline and is no longer found 11 counties throughout its former range. The seasonal wetlands which this forb occurs are disappearing from landscape, often closing transitioning wet forest or drained converted agriculture. We docum...

Species-rich grasslands that become enriched with nitrogen often suffer decreases in species richness, increases in plant biomass, and invasion by weedy exotic species. Suitable techniques to restore enriched grasslands and reestablish native communities are increasingly needed. Here we report results of a 5-yr experiment in enriched coastal prairie grasslands (Bodega Marine Reserve, Bodega Bay...