We investigated the use of stable C and N isotopic ratios as indicators of shifts in nutrient limitation of aquatic macrophytes in native Typha (Typha domingensis Pers.) and Cladium (Cladium jamaicense Crantz) communities growing along the well-established phosphorus enrichment gradient of Water Conservation Area 2A of the Florida Everglades. Both Typha and Cladium had significantly different d...

It is frequently presumed that heterotrophic bacteria from aquatic environments have low carbon (C) content, high phosphorus (P) content, and maintain homeostasis at low C:P in their biomass. Dissolved and particulate organic matter from primary producers in terrestrial and aquatic environments typically has high C:P ratios, suggesting that heterotrophic bacteria consuming this resource experie...

Article Type: Full Length Research Article This study assessed the effect of soil Arsenic (As) on growth height, leaf area, biomass, relative growth rate (RGR), photosynthetic activities [net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs), inter-cellular CO2 concentration (Ci)] and selected antioxidant parameters [superoxide dismutase (SOD), catalase (CAT) and pero...

A toxic shock syndrome isolate of Staphylococcus aureus was grown in a chemostat, in a defined synthetic medium of six amino acids, glucose, two vitamins and salts. Steady states were achieved under limiting and replete Mg2+ conditions and at a range of relative specific growth rates. The biomass and toxic shock syndrome toxin-1 (TSST-1) were estimated at each condition. Under Mg2+ limitation t...

Carnivore (top-down) and resource (bottom-up) influences in food webs are strong and pervasive, but few studies have investigated their interactive effects in speciesrich terrestrial ecosystems. This study focused on arthropods associated with the dominant tree species, Metrosideros polymorpha (Myrtaceae), in Hawaiian forests. Severe soil nutrient limitation on a 120-yr-old lava flow was remove...

this study was carried out to evaluate the changes in some important cell parameters under water limitation in sorghum genotypes. a factorial experiment was conducted based on randomized completely design in greenhouse, in university of mohaghegh ardabili in 2014. treatments were water stress at levels of 85, 65, 45 and 25 percent field capacity in and three genotypes of forage sorghum (kfs2, k...

The combustion in biomass boilers is classified as a non-homogeneous combustion process. This phenomenon is known as difficulty controllable by common control algorithms due to its inappropriate properties e.g. non-linear static characteristics, limitation of control variable quantity, transitions with a time delay or even behavior similar to non-minimal phase systems. Due to these properties t...

A model was developed and calibrated to experimental data, to formulate a theoretical description of nitrification in bead filters. The model results were consistent with the literature, indicating that the inverse relationship between solids accumulation and nitrification is mediated by an oxygen limitation. This result was central to an explanation of why differing optimal backwash intervals ...

Global climate change is expected to increase annual temperatures and decrease summer precipitation in Central Europe. Little is known of how forests respond to the interaction of these climate factors and if their responses depend on soil conditions. In a 3-year lysimeter experiment, we investigated the growth response of young mixed oak stands, on either acidic or calcareous soil, to soil wat...