scholarly journals Temperature‐dependence of minimum resource requirements alters competitive hierarchies in phytoplankton

Oikos ◽  
2019 ◽  
Vol 128 (8) ◽  
pp. 1194-1205 ◽  
Author(s):  
Leah Lewington‐Pearce ◽  
Anita Narwani ◽  
Mridul K. Thomas ◽  
Colin T. Kremer ◽  
Helena Vogler ◽  
...  
Keyword(s):  
Temperature Dependence ◽  
Resource Requirements ◽  
Competitive Hierarchies

scholarly journals An Empiricist’s Guide to Modern Coexistence Theory for Competitive Communities

2019 ◽  
Author(s):  
Casey M. Godwin ◽  
Feng-Hsun Chang ◽  
Bradley Cardinale
Keyword(s):  
Species Coexistence ◽  
Empirical Studies ◽  
Empirical Work ◽  
Relative Fitness ◽  
Empirical Methods ◽  
Coexistence Theory ◽  
Niche Differences ◽  
Rate Versus ◽  
Resource Requirements ◽  
Competitive Hierarchies

AbstractWhile most ecological theories have historically invoked niche differences as the primary mechanism allowing species coexistence, we now know that species coexistence in competitive communities actually depends on the balance of two opposing forces: niche differences (ND) that determine how species limit their own growth rate versus that of their competitor, and relative fitness differences (RFD) that establish competitive hierarchies among species. Several different empirical methods have been proposed for measuring ND and RFD in order to make predictions about coexistence of species, yet it remains unclear which method(s) are appropriate for a given empirical study and whether or not those methods actually yield the same information. Here we summarize and compare five different empirical methods, with the aim of providing a practical guide for empiricists who want to predict coexistence among species. These include two phenomenological methods that estimate ND and RFD based on observing competitive interactions among species; two mechanistic methods that estimate ND and RFD based solely on information about species’ resource requirements; and a fifth method that does not yield ND and RFD but describes the impacts of those forces within communities. Based on the specific requirements, limitations, and assumptions of each approach, we offer a series of decision steps that can be used to determine which method(s) are best for a given study system. In particular, we show there are important tradeoffs between mechanistic methods, which require detailed understanding of species niches and physiology but are more tractable experimentally, and phenomenological methods which do not require this detailed information but can be impractical for some study designs. Importantly, we show that although each method can be used to estimate ND and RFD, the methods do not always yield the same values. Therefore we caution against future syntheses that compile these estimates from different empirical studies. Finally, we highlight several areas where modern coexistence theory could benefit from additional empirical work.

Temperature Dependence of the Critical Electron Dose for Fatty Acid Monolayers

1982 ◽  
Vol 40 ◽  
pp. 78-79
Author(s):  
Kenneth H. Downing ◽  
Robert M. Glaeser
Keyword(s):  
Electron Beam ◽  
Fatty Acid ◽  
Inelastic Scattering ◽  
Temperature Dependence ◽  
Structural Damage ◽  
Direct Result ◽  
Second Step ◽  
Strong Temperature Dependence ◽  
Electron Dose ◽  
Covalent Bonds

The structural damage of molecules irradiated by electrons is generally considered to occur in two steps. The direct result of inelastic scattering events is the disruption of covalent bonds. Following changes in bond structure, movement of the constituent atoms produces permanent distortions of the molecules. Since at least the second step should show a strong temperature dependence, it was to be expected that cooling a specimen should extend its lifetime in the electron beam. This result has been found in a large number of experiments, but the degree to which cooling the specimen enhances its resistance to radiation damage has been found to vary widely with specimen types.

Temperature Dependence of Magnetic Domains and Wall Structures

1972 ◽  
Vol 30 ◽  
pp. 496-497
Author(s):  
Sonoko Tsukahara ◽  
Tadami Taoka ◽  
Hisao Nishizawa
Keyword(s):  
Temperature Dependence ◽  
Domain Walls ◽  
Magnetic Domain ◽  
Iron Film ◽  
Objective Lens ◽  
Lorentz Microscopy ◽  
Domain Structures ◽  
Wall Structures ◽  
Crystal Films ◽  
Metallurgical Structure

The high voltage Lorentz microscopy was successfully used to observe changes with temperature; of domain structures and metallurgical structures in an iron film set on the hot stage combined with a goniometer. The microscope used was the JEM-1000 EM which was operated with the objective lens current cut off to eliminate the magnetic field in the specimen position. Single crystal films with an (001) plane were prepared by the epitaxial growth of evaporated iron on a cleaved (001) plane of a rocksalt substrate. They had a uniform thickness from 1000 to 7000 Å.The figure shows the temperature dependence of magnetic domain structure with its corresponding deflection pattern and metallurgical structure observed in a 4500 Å iron film. In general, with increase of temperature, the straight domain walls decrease in their width (at 400°C), curve in an iregular shape (600°C) and then vanish (790°C). The ripple structures with cross-tie walls are observed below the Curie temperature.

Temperature dependence of generation-recombination noise in p-n junctions

2002 ◽  
Vol 12 (3) ◽  
pp. 71-74
Author(s):  
J. A. Jiménez Tejada ◽  
A. Godoy ◽  
A. Palma ◽  
P. Cartujo
Keyword(s):  
Temperature Dependence

Temperature dependence of spin fluctuation scattering of neutrons on pyrrhotite

1964 ◽  
Vol 25 (5) ◽  
pp. 634-641 ◽  
Author(s):  
Sz. Kraśnicki ◽  
A. Wanic ◽  
Ž. Dimitrijević ◽  
R. Maglić ◽  
V. Marković ◽  
...  
Keyword(s):  
Temperature Dependence ◽  
Spin Fluctuation

TEMPERATURE DEPENDENCE OF PHOTOCONDUCTIVITY IN CdCr2Se4

1971 ◽  
Vol 32 (C1) ◽  
pp. C1-934-C1-936 ◽  
Author(s):  
S. B. BERGER ◽  
A. AMITH
Keyword(s):  
Temperature Dependence
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