In woodland streams, the decomposition of allochthonous organic matter constitutes a fundamental ecosystem process, where aquatic hyphomycetes play a pivotal role. It is therefore greatly affected by water temperature and nutrient concentrations. The individual effects of these factors on the decomposition of litter have been studied previously. However, in the climate warming scenario predicte...

Concentrations of the macronutrients (K, Ca, Mg, Na, P and S) and micronutrients (Fe, B, Zn, Mn and Cu) in whole fruit, pulp, rind and albedo of fruit from young and mature 'Bellamy' navel orange trees were measured at fortnightly intervals during fruit development. The general order of abundance of the macronutrients were K > Ca > Mg ˆ P > S > Na and the abundance of the micronutrients followe...

Competition of three bloom-forming marine phytoplankton (diatom Skeletonema costatum, and dinoflagellates Prorocentrum minimum and Alexandrium tamarense) was studied through a series of multispecies cultures with different nitrate (NaNO3) and phosphate (NaH2PO4) levels and excess silicate to interpret red tide algae succession. S. costatum outgrew the other two dinoflagellates in nitrate and ph...

Nutrient uptake by roots often involves substrate-dependent regulated nutrient transporters. For robust uptake, the system requires a regulatory circuit within cells and a collective, coordinated behaviour across the tissue. A paradigm for such systems is boron uptake, known for its directional transport and homeostasis, as boron is essential for plant growth but toxic at high concentrations. I...

Little information is currently available concerning temporal changes in nutrient transport following the addition of manure to cropland areas. This study was conducted to measure nutrient transport in runoff as affected by tillage and time following the application of beef cattle or swine manure to a site on which corn (Zea mays L.) was grown. Rainfall simulation tests were initiated 4, 32, 62...

1. General hypotheses have related nutrient stoichiometry to physiology and structure for tracheophytes across global resource gradients. These hypotheses have not been tested on bryophytes despite their importance in numerous ecosystem processes. 2. Twelve bryophyte species were sampled across an elevation · soil age matrix representing a dramatic range of climates onMauna Loa, Hawaii. 3. We t...

The aim of this study was to compare how conventional stem harvesting (CH) and whole-tree harvesting (WTH) in the first, and in some cases also in the second, thinning affect the needle nutrient status of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) stands in Finland. A series of 12 long-term field experiments was studied. The experiments were established during ...

We study chemostat models in which multiple species compete for two or more limiting nutrients. First we consider the case where the nutrient flow and species removal rates and input nutrient concentrations are all given positive constants. In that case, we use Brouwer degree theory to give conditions guaranteeing that the models admit globally asymptotically stable componentwise positive equil...

fifteen kinds of local wetland plants in taihu lake region of china were investigated on their respective growth conditions, biomass allocations and nutrient uptake capacities. the test plants were cultured in 3 l nutrient solutions for 28 days with nh4 +-n, no3 --n and p concentrations of 38.5, 132.8 and 10 mg/l, respectively. mean species total biomass ranged from 1.2-21.6 g/plant with above/...

Quality of measurements is an important factor affecting the reliability of analyses in environmental sciences. In this paper we combine foliar measurement data from Finland and results of multiple measurement quality tests from different sources in order to study the effect of measurement quality on the reliability of foliar nutrient analysis. In particular, we study the use of weighted linear...