abstract study on photosynthetic and enzym activity changes in lettuce under cadmium stress has been done in greenhouse. of zhejang university in chine the experimental design was a crd factorial design organized in hydroponic system with 7 replications. cadmium was added to nutrient solution in cdcl2 in three concentrations (0, 2, 4 mg/l). stomatal photosynthetic factors (transpiration, stomat...

The effects of salinity and supplied calcium chloride on growth and leaf ions concentration of tomato (Lycopersicon esculentum L.) were investigated in Gorgan, Iran. A factorial experiment was conducted based on RCBD with four NaCl levels (0, 50, 100, and 150 mM) and four CaCl2 levels (0, 100, 200 and 300 mg L-1). Data of growth, yield and leaf’s Ca, K, and Na content were subjected to analyze ...

Allocation of limited nutrients, such as nitrogen (N) and phosphorus (P), among plant organs reflects the influences of evolutionary and ecological processes on functional traits of plants, and thus is related to functional groups and environmental conditions. In this study, we tested this hypothesis by exploring the stoichiometric scaling of N and P concentrations between twig stems and leaves...

In fertilizer-drawn forward osmosis (FDFO) desalination, the final nutrient concentration (nitrogen, phosphorus, potassium (NPK)) in the product water is essential for direct fertigation and to avoid over fertilization. Our study with 11 selected fertilizers indicate that blending of two or more single fertilizers as draw solution (DS) can achieve significantly lower nutrient concentration in t...

We evaluated differences in the rates and correlates of decomposition among 32 fern and angiosperm litter types collected in Hawai’i. Leptosporangiate ferns were separated into groups based on phylogeny: ‘polypod’ ferns, a monophyletic clade of ferns that diversified in the Cretaceous, and all other (‘non-polypod’) ferns that diversified earlier. We measured initial litter chemistry (nutrients ...

Many microorganisms rely on binding-protein (BP) assisted, active transport systems for scavenging of scarce nutrients. Several hypotheses have been raised to explain the advantage of such uptake systems; attempting to rationalise the benefits of the relatively high BP concentrations in the periplasm and the coupling of transport to free energy transduction. Despite the appeal of these hypothes...

Reducing phosphorus (P) loading to rivers is seen as a key mitigation measure to improve aquatic ecology and control excessive algal growth, as P is widely assumed to be the limiting nutrient in most rivers. Nutrient enrichment experiments using within-river flume mesocosms were conducted in the oligotrophic River Rede, to determine how periphyton accrual was affected by increasing P concentrat...

We study chemotaxis of a single E. coli bacterium in a medium where the nutrient chemical is also undergoing diffusion and its concentration has the form of a Gaussian whose width increases with time. We measure the average first passage time of the bacterium at a region of high nutrient concentration. In the limit of very slow nutrient diffusion, the bacterium effectively experiences a Gaussia...