Human-caused alterations of the carbon and nutrient cycles are expected to impact tropical ecosystems in the near future. Here we evaluated how a combined change in carbon (C), nitrogen (N) and phosphorus (P) availability affects soil and litter microbial respiration and litter decomposition in an undisturbed Amazonian rainforest in French Guiana. In a fully factorial C (as cellulose), N (as ur...

Climate warming could increase rates of soil organic matter turnover and nutrient mineralization, particularly in northern high-latitude ecosystems. However, the effects of increasing nutrient availability on microbial processes in these ecosystems are poorly understood. To determine how soil microbes respond to nutrient enrichment, we measured microbial biomass, extracellular enzyme activities...

The changes in agricultural policy and the increased concern about the effects of intensive production systems on the natural environment may lead to a reduction in the levels of nitrogen Ž . N fertilization on grassland. The aim of this review is to quantify the consequences of lowering N fertilization on dairy cow nutrition. For grass species harvested at the same age of regrowth, a Ž . reduc...

We report an ion channel in the plasma membrane of unfertilized oocytes of the ascidian Ciona intestinalis that is directly gated by the second messenger ADP-ribose. The ion channel is permeable to Ca2+ and Na+ and is characterized by a reversal potential between 0 and +20 mV and a unitary conductance of 140 pS. Preinjection of the Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane- N, N, N', N'-tetra...

To evaluate plant and herbivore responses to nitrogen we conducted a fertilization study at a low and high pollution site in the mixed conifer forests surrounding Los Angeles, California. Contrary to expectations, discriminant function analysis of oak herbivore communities showed significant response to N fertilization when atmospheric deposition was high, but not when atmospheric deposition wa...

Background: To evaluate whether success of fertilization and embryo quality are more probable when follicular fluid Anti-mullerian hormone levels are higher . Materials and Methods: 62 women who underwent IVF cycle were divided into fertilized oocytes group (n=42) and non- fertilized oocytes group (n=20) . Follicular fluid Anti-mullerian hormone levels were measured in both groups. Results: Ant...

Nitrogen fertilizer is one of the largest input costs for growing corn. Across the Corn Belt, N is typically the most yield-limiting nutrient. Facing record high N fertilizer prices and potential supply problems, producers are concerned about N fertilization rates. Soil fertility researchers and extension specialists from seven states across the Corn Belt (see list in acknowledgements section) ...

not result in higher color ratings in the spring and resulted in inefMany turfgrass managers apply a portion of the total yearly N to cool-season turfgrasses in the late fall (November). The purpose of this field study was to compare fertilization programs with and without N applications in November using both slow-release and soluble N sources. Turfs of two different cultivars of Kentucky blue...

Climate warming could increase rates of soil organic matter turnover and nutrient mineralization, particularly in northern high-latitude ecosystems. However, the effects of increasing nutrient availability on microbial processes in these ecosystems are poorly understood. To determine how soil microbes respond to nutrient enrichment, we measured microbial biomass, extracellular enzyme activities...