Nutrient limitation and resource competition in bacterial and phytoplankton communities may appear different when considering different levels of taxonomic resolution. Nutrient amendment experiments conducted in a boreal lake on three occasions during one open water season revealed complex responses in overall bacterioplankton and phytoplankton abundance and biovolume. In general, bacteria were...

OBJECTIVE Because the percentage of missing portion sizes was large in the Aerobics Center Longitudinal Study (ACLS), careful consideration of the accuracy of standard portion sizes was necessary. The purpose of the present study was to investigate the consequences of using standard portion sizes instead of reported portion sizes on subjects' nutrient intake. METHODS In 2307 men and 411 women...

Changes in land use may lead to increased soil nutrient levels in many ecosystems (e.g. due to intensification of agricultural fertilizer use). Plant species differ widely in their response to differences in soil nutrients, and for savannas it is uncertain how this nutrient enrichment will affect plant community dynamics. We set up a large controlled short-term experiment in a semi-arid savanna...

Most previous studies have ascribed variations in the resorption of a certain plant nutrient to its corresponding environmental availability or level in tissues, regardless of the other nutrients' status. However, given that plant growth relies on both sufficient and balanced nutrient supply, the nutrient resorption process should not only be related to the absolute nutrient status, but also be...

Annual variations in biogeochemical and physical processes can lead to nutrient variability and seasonal patterns in phytoplankton productivity and assemblage structure. In many coastal systems river inflow and water exchange with the ocean varies seasonally, and alternating periods can arise where the nutrient most limiting to phytoplankton growth switches. Transitions between these alternatin...

abstract pistachio ( pistacia vera l.) is an important crop in our country and has a unique position in export goods. in respect to better nut quality this research was conducted during 2005-2006. macro and micronutrients were used as foliar application to surmount soil limitations in nutrient uptake and alternate bearing control with “owhadi” cultivar in rcbd with 3 replications. the treatment...

We used a fully factorial experimental design to examine the simultaneous effects of light availability, absolute nutrient (nitrogen and phosphorus) availability, relative N : P availability, and trophic structure on zooplankton community composition and the abundance and stoichiometry of algal producers. During May–June 2000, we created gradients of light and nutrient supply and predation risk...

Background and Objectives: An association between socioeconomic status (SES) and poor health has been recognized. Inequalities in nutrition have been associated with inequalities in health. This study aimed to identify the social variability in the food and nutrient intake of Iranian households. Materials and Methods: This study was conducted in the framework of the Comprehensive Study on Hous...

the use of fertilizers in agriculture is a potential source of environmental pollution especially in ‎water quality and soil resources. the study of effective factors on water and nutrient transport ‎through soil profile is helpful for nutrient management to minimize adverse impacts on environment ‎and nitrate leaching below root zone. in this study, for assessing the nitrate transportation bel...