Pollen productivity, dispersal, and correction factors for major tree taxa in the Swiss Alps based on pollen-trap results

2008 ◽  
Vol 152 (3-4) ◽  
pp. 200-210 ◽  
Author(s):  
Per Sjögren ◽  
W.O. van der Knaap ◽  
Antti Huusko ◽  
Jacqueline F.N. van Leeuwen
Keyword(s):  
Swiss Alps ◽  
Correction Factors ◽  
Pollen Trap ◽  
Pollen Productivity

scholarly journals The Relative Pollen Productivity and Pollen Representation of North European Trees, and Correction Factors for Tree Pollen Spectra. Determined by Surface Pollen Analyses from Forests

1970 ◽  
Vol 96 ◽  
pp. 1-99
Author(s):  
Svend Th. Andersen
Keyword(s):  
Tree Species ◽  
Small Sample ◽  
Forest Composition ◽  
Pollen Deposition ◽  
Correction Factors ◽  
Tree Crown ◽  
Tree Pollen ◽  
Surface Samples ◽  
Pollen Productivity ◽  
Pollen Analyses

The present work deals primarily with a determination of the relative pollen productivity of various trees from North Europe by means of their representation in pollen analyses of surface samples from forests, with the aim to calculate correction factors for pollen diagrams.Surface samples from 2 forests in Denmark were examined. The forest composition was determined by tree crown areas and tree basal areas in small sample plots. The relation of the tree crown areas to the tree basal areas was determined for the various tree species, and the data for crown area composition, basal area composition and tree frequency were compared.The pollen preservation in the various surface samples was examined.Data on wind conditions are mentioned in the chapter about pollen dispersal in the forest, and the various modes of pollen transfer are discussed. The amount of exotic pollen in the samples is used as a calculation basis for the tree pollen frequencies, and the occurrence and composition of the exotic pollen is discussed.The relationship of the forest composition to the tree pollen deposition is discussed. Pollen deposition and pollen productivity is expressed by a regression equation. The relative pollen productivity of the tree species is expressed in relation to a reference species, in the present case Fagus silvatica. Pollen representation and relative pollen representation are determined by a comparison of pollen percentages with percentages for areal frequency.Pollen productivity factors, pollen representation and correction factors were determined for Danish species of Quercus, Betula, Alnus, Carpinus, Ulmus, Fagus, Tilia and Fraxinus by means of the pollen frequencies in the surface samples. Corrected pollen percentages were compared with the tree areal percentages in the sample plots. Data for the pollen frequencies of forest plants other than the trees are presented. The data on trees from Denmark are compared with other data from Northern Europe, and correction factors were calculated for species of Pinus, Picea and Abies.Tree pollen spectra from outside the forest are discussed and the relative pollen representation is calculated. The present calculations of the relative pollen productivity of the trees are compared with previous estimates, and the application of the correction factors to pollen diagrams is discussed.

The development of composite dispersal functions for estimating absolute pollen productivity in the Swiss Alps

2010 ◽  
Vol 19 (4) ◽  
pp. 341-349 ◽  
Author(s):  
Per Sjögren ◽  
Simon E. Connor ◽  
Willem O. van der Knaap
Keyword(s):  
Swiss Alps ◽  
Pollen Productivity

Weaning Weight Correction Factors from Angus Field Data

1978 ◽  
Vol 47 (1) ◽  
pp. 124-130 ◽  
Author(s):  
J. H. Anderson ◽  
R. L. Wilham
Keyword(s):  
Field Data ◽  
Correction Factors ◽  
Weaning Weight ◽  
Weight Correction

Поправочные коэффициенты в формулах для расчета содержания примесей: сущность, способы определения и их ограничения

2019 ◽  
Vol 53 (5) ◽  
pp. 55-60 ◽  
Author(s):  
Наум Аронович Эпштейн
Keyword(s):  
Correction Factors ◽  
Response Factors ◽  
Relative Response

Представлены формулы для расчета коэффициентов относительной чувствительности RRF (relative response factors) и поправочных коэффициентов F (correction factors) примесей, а также формулы, необходимые для понимания сущности коэффициентов RRF и F. Рассмотрены основные способы определения поправочных коэффициентов и их ограничения (условия, выполнение которых необходимо для корректного определения RRF и F). Эти ограничения не отражены в Европейской фармакопее и в Фармакопее США, но от их учета зависит правильность определения значений поправочных коэффициентов. Приведены примеры и даны рекомендации для надежного определения и правильного использования поправочных коэффициентов.

Essai d'application de modèles météorologiques au calcul du moment d'apparition de deux phases phénologiques | Application of Meteorological Models for the Calculation of the Beginning of Two Phenological Phases

2000 ◽  
Vol 151 (10) ◽  
pp. 385-397
Author(s):  
Bernard Primault
Keyword(s):  
Sunshine Duration ◽  
Fruit Trees ◽  
Swiss Alps ◽  
Winter Solstice ◽  
Phenological Data ◽  
Thermal Thresholds ◽  
The Mean ◽  
Two Parameters ◽  
Meteorological Models ◽  
Phenological Phases

Many years ago, a model was elaborated to calculate the«beginning of the vegetation's period», based on temperatures only (7 days with +5 °C temperature or more). The results were correlated with phenological data: the beginning of shoots with regard to spruce and larch. The results were not satisfying, therefore, the value of the two parameters of the first model were modified without changing the second one. The result, however, was again not satisfying. Research then focused on the influence of cumulated temperatures over thermal thresholds. Nevertheless, the results were still not satisfying. The blossoming of fruit trees is influenced by the mean temperature of a given period before the winter solstice. Based on this knowledge, the study evaluated whether forest trees could also be influenced by temperature or sunshine duration of a given period in the rear autumn. The investigation was carried through from the first of January on as well as from the date of snow melt of the following year. In agricultural meteorology, the temperature sums are often interrelated with the sunshine duration, precipitation or both. However,the results were disappointing. All these calculations were made for three stations situated between 570 and 1560 m above sea-level. This allowed to draw curves of variation of the two first parameters (number of days and temperature) separately for each species observed. It was finally possible to specify the thus determined curves with data of three other stations situated between the first ones. This allows to calculate the flushing of the two tree species, if direct phenological observation is lacking. This method, however, is only applicable for the northern part of the Swiss Alps.

Preventing Accidental Spills: Risk Analysis and the Discharge Permitting Process

1994 ◽  
Vol 29 (3) ◽  
pp. 189-197 ◽  
Author(s):  
Frans A. N. van Baardwijk
Keyword(s):  
Risk Analysis ◽  
Surface Waters ◽  
Legal Framework ◽  
Sewage Water ◽  
Correction Factors ◽  
Analysis Method ◽  
Sewage Water Treatment ◽  
Accident Scenarios ◽  
Contaminating Substances ◽  
Permitting Process

The contribution of accidental discharges to the total emission of contaminating substances in surface waters is relatively increasing, as regular discharges are reduced. In The Netherlands a program has been started to develop a quantitative risk analysis method to be used within the discharge permitting process. The methodology takes into account the type of activities and related accident scenarios in terms of failure frequencies and source sizes, correction factors according to specific circumstances, as well as the nature of the receiving system (types of surface waters, but also public sewage water treatment plants). The methodology will provide an indication of the risk reduction needed in terms of reducing the frequency and/or the volume of possible spills. The method itself, the use of it within the legal framework and the relation with the EC-Directives are discussed.

Near-field correction factors for elliptical fibres

1980 ◽  
Vol 16 (15) ◽  
pp. 580 ◽  
Author(s):  
Hansen J.J. Ramskov ◽  
M.J. Adams ◽  
A. Ankiewicz ◽  
F.M.E. Sladen
Keyword(s):  
Near Field ◽  
Correction Factors
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