Reform, Standards and Teacher Identity: Challenges of Sustaining Commitment

Teacher commitment has been found to be a critical predictor of teachers�� work performance, absenteeism, retention, burnout and turnover, as well as having an important influence on students�� motivation, achievement, attitudes towards learning and being at school (Firestone (1996). Educational Administration Quarterly, 32(2), 209���235; Graham (1996). Journal of Physical Education, Recreation and Dance, 67(1), 45–47; Louis (1998). School Effectiveness and School Improvement, 9(1), 1��27; Tsui & Cheng (1999). Educational Research and Evaluation, 5(3), 249���268). It is also a necessary ingredient to the successful implementation, adaptation or resistance reform agendas. Surprisingly, however, the relationship between teachers�� motivation, efficacy, job satisfaction and commitment, and between commitment and the quality of their work has not been the subject of extensive research. Some literature presents commitment as a feature of being and behaving as a professional (Helsby, Knight, McCulloch, Saunders, & Warburton (1997). A report to participants on the professional cultures of Teachers Research Project, Lancaster University, January). Others suggest that it fluctuates according to personal, institutional and policy contexts (Louis (1998). School Effectiveness and School Improvement, 9(1), 1��27) and identify different dimensions of commitment which interact and fluctuate (Tyree (1996). Journal of Educational Research, 89(5), 295��304). Others claim that teachers’ commitment tends to decrease progressively over the course of the teaching career (Fraser, Draper, & Taylor (1998). Evaluation and Research in Education, 12 (2), 61���71; Huberman (1993). The lives of teachers. London: Cassell). In this research, experienced teachers in England and Australia were interviewed about their understandings of commitment. The data suggest that commitment may be better understood as a nested phenomena at the centre of which is a set of core, relatively permanent values based upon personal beliefs, images of self, role and identity which are subject to challenge by change which is socio-politically constructed.

Pollen Sources

This chapter reviews what is known about abundance and distribution of the 12 most important aeroallergenic pollens in Europe: Ambrosia, Alnus, Artemisia, Betula, Chenopodiaceae, Corylus, Cupressaceae/Taxaceae, Olea, Platanus, Poaceae, Quercus and Urtica/Parietaria. Abundance is based on 10 years of pollen records from 521 stations of the European Aeroallergen Network that were interpolated into 12 distribution maps covering most of Europe. The chapter compares the distribution maps with other types of distribution maps that are available for selected tree species and discuss two methods for making harmonized pollen source inventories: ���bottom-up��� and ��top-down”. Both methods have advantages and disadvantages, and both need to be explored and further developed. Remote sensing has shown to be a valuable method to improve the inventories, especially the use of satellites. The full potential as well as limitations of remote sensing in relation to pollen sources remains to be explored. The review suggests that the most probable way of obtaining inventories of all 12 pollen species is to use top-down methods that use an ecosystem-based approach that for each particular species connects ecological preference, pollen counts and remote sensing.

Lessons Learnt From Ragweed and Birch Studies

Here we review some of the most important aspects of recent work on Ragweed (Ambrosia) and birch (Betula) concerning: 1) sources, 2) trends & phenology and 3) dispersion and transformation. Sources: At Northern latitudes the birch fraction in forests usually exceeds 50% of all broadleaved trees and the abundance of birch decreases with latitude from 5%-20% in many mid-latitude regions and down to 0%-2% in more southern areas. Birches are also commonly found in small woodlands or planted as ornamental trees in urban areas. Ragweeds are herbaceous weed species that are associated with areas of disturbance. Ragweed is native to North America, but considered an invasive species in Europe, Australia and China. In Europe, the four main centres are: The Pannonian Plain, Ukraine, The Po Valley (Italy) and the Rhone Valley (France). Trends & Phenology: Birch pollen seasons have started earlier during the last decades. This trend appears have decreased during recent years despite increasing spring temperatures. Ragweed tends to experience less change in flowering date as ragweed flowering depends on photoperiod. Ragweed is increasing its distribution in Europe, but airborne concentrations of ragweed pollen are not universally increasing, e.g. due to control measures or pest attacks. Dispersion & transformation: The beginning of the birch pollen season is often heralded by episodes of Long Distance Transport (LDT) from the south. Similar LDT episodes are intermittently seen for ragweed, which can reach as far north as Scandinavia. Humidity and air pollution can modify pollen grains during atmospheric transport. This can cause a change in allergenic potential of the pollen grain and is a direction for future research including the effect of co-exposure of air pollution and the transformation of aeroallergens.

Ragweed (Ambrosia) Pollen Source Inventory for Austria

This study improves the spatial coverage of top-down Ambrosia pollen source inventories for Europe by expanding the methodology to Austria, a country that is challenging in terms of topography and the distribution of ragweed plants. The inventory combines annual ragweed pollen counts from 19 pollen-monitoring stations in Austria (2004–2013), 657 geographical observations of Ambrosia plants, a Digital Elevation Model (DEM), local knowledge of ragweed ecology and CORINE land cover information from the source area. The highest mean annual ragweed pollen concentrations were generally recorded in the East of Austria where the highest densities of possible growth habitats for Ambrosia were situated. Approximately 99% of all observations of Ambrosia populations were below 745 m. The European infection level varies from 0.1% at Freistadt in Northern Austria to 12.8% at Rosalia in Eastern Austria. More top-down Ambrosia pollen source inventories are required for other parts of Europe.