297 research outputs found
Structure and dynamics of Allantospermum borneense Form. (Simaroubaceae) in 52-ha plots at Lambir Hills National Park, Miri, Sarawak.
EXAMINING COMPETENCE IN ACTION RESEARCH OF BASIC EDUCATION TEACHERS IN CEBU CITY, PHILIPPINES
Background and Purpose: This study examined the self-perceived competence in action research components of basic education teachers in Cebu City as one form of identifying their challenges in doing AR. The results aimed to provide baseline information for the planned professional development program.
Methodology: It employed a sequential explanatory design (QUAN→qual). It is characterized by collecting and analyzing quantitative data in the primary phase and then by collecting and analyzing qualitative data. There were 166 teachers who participated in the online survey. These teachers previously underwent professional development programs in designing AR projects, and two-thirds did an AR. Using their responses, they were grouped through a hierarchical clustering technique to create distinct groups of teachers sharing the similarity of competence or needs in the AR components. The cluster analysis yields four groups. Eventually, eight teachers were interviewed regarding their responses, which means two teachers represented each cluster.
Findings: For very few teachers in cluster one (n=4), they regard selecting AR topic, planning the project, analyzing and presenting data, and integrating ethics as areas of non-difficulty while integrating technology, reflecting on AR, and communicating results as areas of difficulty. For the majority of the teachers belonging in cluster 2 (n=76), cluster 3 (n=37), and cluster 4 (n=49), all AR components are regarded as difficult, indicating all are critical areas for professional development.
Contributions: A conventional way of conducting needs assessment of teachers’ competence in AR as a basis for professional development program is done through calculating the mean and standard deviation per AR competence or skills of all teachers participating in a survey. However, this method disregards the individual professional needs of teachers as it presents the general level of competence in each skill set. The professional needs may vary from one teacher to another. Thus, this study presents a novel way of examining teachers’ needs in AR by using cluster analysis to homogenously group participants according to the similarity of their responses or professional needs. This gives key reference points on which AR skills need to be improved for teachers belonging to the same group when planning a teacher development program in AR.
Keywords: Action research, competence, in-service teacher, professional development, teacher research.
Cite as: Cortes, S. T., Pineda, H. A., & Geverola, I. J. R. (2021). Examining competence in action research of basic education teachers in Cebu city, Philippines. Journal of Nusantara Studies, 6(2), 202-230. http://dx.doi.org/10.24200/jonus.vol6iss2pp202-23
Nitrogen uptake strategies of edaphically specialized Bornean tree species
The association of tree species with particular soil types contributes to high b diversity in forests, but the mechanisms producing such distributions are still debated. Soil nitrogen (N) often limits growth and occurs in differentially available chemical forms. In a Bornean forest where tree species composition changes dramatically along a soil gradient varying in supplies of different N-forms, we investigated whether tree species’ N-uptake and soil specialization strategies covaried. We analyzed foliar 15N natural abundance for a total of 216 tree species on clay or sandy loam (the soils at the gradient’s extremes) and conducted a 15N-tracer experiment with nine specialist and generalist species to test whether species displayed flexible or differential uptake of ammonium and nitrate. Despite variation in ammonium and nitrate supplies and nearly 4 % difference in foliar δ15N between most soil specialists and populations of generalists on these soils, our 15N tracer experiment showed little support for the hypothesis that soil specialists vary in N-form use or the ratios in which they use these forms. Instead, our results indicate that these species possess flexible capacities to take up different inorganic N forms. Variation between soil specialists in uptake of different N forms is thus unlikely to cause the soil associations of tree species and high b diversity characteristic of this Bornean rain forest. Flexible uptake strategies would facilitate N-acquisition when supply rates of N-forms exhibit spatiotemporal variation and suggest that these species may be functionally redundant in their responses to N gradients and influences on ecosystem N-cycles
Correlated changes of wood stick decomposition with local environmental factors in a forest dynamics plot at Lambir Hills National Park, Sarawak
Ecology of Kapur (Dryobalanops) - A synthesis of findings from a 15-year population study at Lambir -
Modification and preservation of environmental signals in speleothems
Speleothems are primarily studied in order to generate archives of climatic change and results have led to significant advances in identifying and dating major shifts in the climate system. However, the climatological meaning of many speleothem records cannot be interpreted unequivocally; this is particularly so for more subtle shifts and shorter time periods, but the use of multiple proxies and improving understanding of formation mechanisms offers a clear way forward. An explicit description of speleothem records as time series draws attention to the nature and importance of the signal filtering processes by which the weather, the seasons and longer-term climatic and other environmental fluctuations become encoded in speleothems. We distinguish five sources of variation that influence speleothem geochemistry: atmospheric, vegetation/soil, karstic aquifer, primary speleothem crystal growth and secondary alteration and give specific examples of their influence. The direct role of climate diminishes progressively through these five factors. \ud
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We identify and review a number of processes identified in recent and current work that bear significantly on the conventional interpretation of speleothem records, for example: \ud
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1) speleothem geochemistry can vary seasonally and hence a research need is to establish the proportion of growth attributable to different seasons and whether this varies over time. \ud
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2) whereas there has traditionally been a focus on monthly mean �´18O data of atmospheric moisture, current work emphasizes the importance of understanding the synoptic processes that lead to characteristic isotope signals, since changing relative abundance of different weather types might 1Corresponding author, fax +44(0)1214145528, E-mail: [email protected] control their variation on the longer-term. \ud
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3) the ecosystem and soil zone overlying the cave fundamentally imprint the carbon and trace element signals and can show characteristic variations with time. \ud
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4) new modelling on aquifer plumbing allows quantification of the effects of aquifer mixing. \ud
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5) recent work has emphasized the importance and seasonal variability of CO2-degassing leading to calcite precipitation upflow of a depositional site on carbon isotope and trace element composition of speleothems. \ud
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6) Although much is known about the chemical partitioning between water and stalagmites, variability in relation to crystal growth mechanisms and kinetics is a research frontier. \ud
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7) Aragonite is susceptible to conversion to calcite with major loss of chemical information, but the controls on the rate of this process are obscure. \ud
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Analytical factors are critical to generate high-resolution speleothem records. A variety of methods of trace element analysis are available, but standardization is a common problem with the most rapid methods. New stable isotope data on Irish stalagmite CC3 compares rapid laser-ablation techniques with the conventional analysis of micromilled powders and ion microprobe methods. A high degree of comparability between techniques for �´18O is found on the mm-cm scale, but a previously described high-amplitude oxygen isotope excursion around 8.3 ka is identified as an analytical artefact related to fractionation of the laser-analysis associated with sample cracking. High-frequency variability of not less than 0.5o/oo may be an inherent feature of speleothem �´18O records
Nonrandom processes maintain diversity in tropical forests
An ecological community\u27s species diversity tends to erode through time as a result of stochastic extinction, competitive exclusion, and unstable host-enemy dynamics. This erosion of diversity can be prevented over the short term if recruits are highly diverse as a result of preferential recruitment of rare species or, alternatively, if rare species survive preferentially, which increases diversity as the ages of the individuals increase. Here, we present census data from seven New and Old World tropical forest dynamics plots that all show the latter pattern. Within local areas, the trees that survived were as a group more diverse than those that were recruited or those that died. The larger (and therefore on average older) survivors were more diverse within local areas than the smaller survivors. When species were rare in a local area, they had a higher survival rate than when they were common, resulting in enrichment for rare species and increasing diversity with age and size class in these complex ecosystems
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