Classification of plant communities and fuzzy diversity of vegetation systems

After stressing the need to keep separated the concept of variability and/or inequality and dissimilarity from that of diversity, it is suggested that diversity of a system should be measured primarily by the number of different classes (K) we can define in it (richness) by classification or identification processes. An index d, ranging between 0 and 1, that summarizes the similarity pattern within the system, can be used if necessary to transform K to a “fuzzy” diversity number, according to the idea that the higher is the similarity within the system the lower should be its diversity. Another index, r, is proposed to measure the “loss” of diversity due to similarity within the system, an index that fits the concept of “redundancy”. Since every diversity vector may be interpreted as a crisp symmetric similarity matrix, of which the Gini-Simpson’s index is the average dissimilarity, while the index of Shannon is the entropy of its eigenvalues, the index d can be chosen to quantify one among the following similarities: a) the overall average similarity of the classes considering the within classes similarity equal to 1 and the between classes similarity equal to 0 (crisp similarity pattern): this is coincident with the evenness of the proportion of importance of the classes, b) the average similarity between the classes without considering evenness, or c) the combination of the two similarities (similarity between the classes and evenness). In these last two cases, the similarity between the classes is characterizing the similarity pattern of a system in a fuzzy way (fuzzy diversity). It is stressed that the diversity of vegetation systems may be of two complementary types: plant individual-based diversity and plant community-based diversity. If we assume that each plant community type corresponds to one habitat then habitat diversity (or niche width) can be calculated for each class of plant individuals according to the number of classes of plant communities in which we can find it. Habitat diversity can be used to measure the indicator value of species or other classes of plant individuals and of plant communities. In this last case, we have to consider the distribution of plant communities in classes defined by environmental factors. It is suggested that the terminology alpha, beta, gamma diversity can be useful only if used to distinguish types of diversity in vegetation systems: alpha diversity = plant individual based diversity, gamma diversity = the union of alpha diversities, beta diversity = plant community based diversity. Thanks to the availability of mathematical tools, it is concluded that rather than being worried about measuring diversity it would be more fruitful to worry about why we are willing to measure it

What Is Most Desirable for Nature? An Analysis of Azorean Pupils’ Biodiversity Perspectives When Deciding on Ecological Scenarios

Understanding pupils’ biodiversity perspectives is essential to developing educators’ sensitivity to students’ multi-faceted views of the world, thus increasing teaching effectiveness. In this study, we asked 1528 school pupils in the Azores to choose between alternative schemes in three ecological scenarios and to justify their decisions. The study’s objectives were to understand biodiversity perspectives underlying pupils’ choice of the most desirable schemes for nature and to examine whether gender and school level (middle school/high school) influenced their choices. Quantitative (frequency analysis and Chi-square statistics) and qualitative (thematic analysis) methods were applied for data analysis. The majority of pupils made appropriate choices, arguing from different biodiversity perspectives, which were classified in 10 categories and 24 subcategories. High school pupils did not exhibit significant differences among the main arguments employed, and mostly referred to ecological concepts, while middle school pupils exhibited different choices according to gender, emphasizing richness over the threats posed by introduced species. Biodiversity education should thus be strengthened, especially at the middle school level, where different complex issues would benefit from classroom discussion and systematization. The chosen methodological strategy proved to be effective in assessing pupils’ biodiversity perspectives, which may be useful to deal with other ill-structured problems.The research was financially supported by THE PORTUGUESE FOUNDATION FOR SCIENCE AND TECHNOLOGY (FUNDAÇÃO PARA A CIÊNCIA E A TECNOLOGIA-FCT) through the projects PTDC/CED-EDG/31182/2017, PTDC/BIA-BEC-104571/2008; IRA was funded by Portuguese funds through FCT under the Norma Transitória-DL57/2016/CP1375/CT0003.info:eu-repo/semantics/publishedVersio

Composition and change of maritime hammock flora in east-central Florida after 20 years

The vegetation of eight east-central Florida maritime hammocks studied in 1997 were compared to similar data collected over 20 years ago. Study sites are located in the northern half of the Indian River Lagoon system mostly within Canaveral National Seashore and Merritt Island National Wildlife Refuge. The upland hammock vegetation throughout the state generally has an oak-palm association, but here these species dominate. Results show that sabal palm, live oak, laurel oak, and pignut hickory, the four dominant tree species in 1976-77, are still dominant in 1997; however, there has been a loss in tree species richness. Most shrub species found during both studies increased in dominance over the 20 years and there was almost a complete turnover in the composition of herbs. Variability in winter freeze events has caused a unique mixture of plant species to occur here. Many of the maritime hammock’s tropical plants are in the northern limit of their range, giving these hammocks a unique ecotonal character. Tropical invasive exotics have increased in frequency, density, and basal area and pose a threat to this diverse floral complex

Evaluation: from Precision, Recall and F-measure to ROC, Informedness, Markedness and Correlation

Commonly used evaluation measures including Recall, Precision, F-Measure and Rand Accuracy are biased and should not be used without clear understanding of the biases, and corresponding identification of chance or base case levels of the statistic. Using these measures a system that performs worse in the objective sense of Informedness, can appear to perform better under any of these commonly used measures. We discuss several concepts and measures that reflect the probability that prediction is informed versus chance. Informedness and introduce Markedness as a dual measure for the probability that prediction is marked versus chance. Finally we demonstrate elegant connections between the concepts of Informedness, Markedness, Correlation and Significance as well as their intuitive relationships with Recall and Precision, and outline the extension from the dichotomous case to the general multi-class case

An Introduction to Zooarchaeology

zooarchaeology is a self-reproducing field taught in many university departments of anthropology or archaeology. As archaeologists have literally taken faunal analysis into their own hands, they have debated how best to use animal remains to study everything from early hominin hunting or scavenging to animal production in ancient market economies. Animal remains from archaeological sites have been used to infer three kinds of information: the age of deposits (chronology); paleoenvironment and paleoecological relations among humans and other species; human choices and actions related to use of animals as food and raw materials. Methods for reconstructing human diet and behavior have undergone the greatest growth over the last four decades, and most of this book addresses the second and third areas. This book deals with what I know best: vertebrate zooarchaeology, and within that, analysis of mammalian bones and teeth

The use of contemporary and historic diatom assemblages in the derivation of reference state communities for rivers in KwaZulu-Natal, South Africa

Reference state conditions of minimally disturbed headwaters were identified from present-day and historic diatom data of key rivers within the selected study area, with the main purpose of establishing diatom reference state communities

Human behavioural ecology, anthropogenic impact and subsistence change at the teouma lapita site, central Vanuatu, 3000-2500 BP

This thesis investigates early human palaeoecological interaction at the Teouma Lapita site on Efate Island, central Vanuatu, and how it changed during a period of cultural transition between 3000-2500 BP. Here I take a quantified approach through an evolutionary ecological theoretical framework using optimal foraging models (Prey Choice, Patch Choice and Central Place Foraging) to generate predictions of optimal economic behaviour in response to temporal variation in prey abundances. These optimal foraging models (OFM) which typically focus on foraging cultures had to be adjusted to the broad spectrum Lapita mixed economy which combined foraging within marine and terrestrial resource patches and horticulture, incorporating pig husbandry and plant cultivation. To this end mammal, bird and reptile vertebrate taxa were divided into three broad resource patches, coastal, terrestrial and the domestic patch. Alternative social theoretical perspectives were also built into the models such as costly signalling theory. OFM predictions were then tested using multiple zooarchaeological datasets to demonstrate changes in foraging efficiency and mobility between resource patches as a result of human induced resource depression. Datasets used include measures of prey diversity, relative abundance, demography, skeletal element representation, and butchery intensity. The results indicate that Lapita foragers focused initially on high ranked fruit bat and large bodied sea turtle resources in concentrated and predictable proximal locations which yielded high post encounter return rates. Giant tortoise exploitation in distant resource patches gained in importance over time as these proximal resource patches became depleted. Domestic patch resources were established and pig abundances increased very quickly but had initially high infant mortality rates due to nutritional deficiency and/or selective culling to reduce associated labour costs. Pigs were closely managed and regulated for a range of purposes which included daily household meat consumption as well as ritualistic feasting events. Faunal abundances peaked during the later post-cemetery period as Lapita settlement and foraging intensified which had a huge impact on the terrestrial and coastal resources due in part to direct foraging, forest clearance. An ecological tipping point followed which saw the disappearance of crocodile and a number of fruit bat and bird species from the record. As encounter rates of high ranked taxa declined so did foraging efficiency and the transition from Lapita to post-Lapita culture saw a dramatic change in subsistence patterns. Tortoise and sea turtle nesting populations were devastated as giant tortoises became extinct around the transition between Lapita to early Erueti, rat demography and the large New Guinea Spiny rat declined likely as a result of human predation as settlement intensity appears to have peaked by the end of the Lapita period. Pig production also declined likely in response to ecological and social developments, and a switch to hunting feral pigs may have occurred. These subsistence changes and declines in foraging efficiency appear to have been associated with changes in settlement patterns which conform to the ideal free distribution model as well as declines in social stratification

Teaching Musical Meter to School-Age Students Through The Ski-Hill Graph

This thesis, Teaching Musical Meter to School-Age Students Through the Ski-Hill Graph, aims to demonstrate the “pedagogability” of modern meter theory, that is, that new scholarship on meter can translate into a coherent and practically implementable instructional curriculum, with various advantages for school-age students. The curriculum model developed in the thesis is derived from Richard Cohn’s work on and approaches to meter theory, which focuses on “sound rather than notation” and graphic representations of meter through mathematical music theory. The materials set out in the thesis demonstrate ways students might be taught to articulate their experience of meter. A unified approach, it incorporates Cohn’s ski-hill graph and other instruments of mathematical music theory such as the SkiHill app, numbering for counting meter, cyclic graphs, and beat-class theory. Among the outcomes it anticipates is a deeper engagement with music in classroom settings. Through this new foundation, where meter studies fits more compatibly with studies of tonality, students should logically be able to perform, compose, and analyse music both aurally and visually with increased confidence and understanding

Putting ecological theories to the test : individual-based simulations of synthetic microbial community dynamics

Microbial communities are critical for the proper functioning of each and every ecosystem on Earth. The ability to understand the structure and functioning of these complex communities is crucial to manage and protect natural communities, as well as to rationally design engineered microbial communities for important applications ranging from medical and pharmaceutical uses to various bioindustrial processes. In recent years, synthetic microbial communities have gained increasing interest from microbiologists due to their reduced complexity and increased controllability, which favours them over more complex natural systems for examining ecological theories. In this thesis, the in silico counterpart of this approach was used to test ecological theories relating to biodiversity and functionality through the use of mathematical models. Models are abstractions of reality which allow for the testing of hypotheses in a controlled way. In this thesis, individual-based models of synthetic microbial communities were developed and used in simulation studies to answer research questions relating to community diversity, stability, productivity and functionality. The models are spatially explicit and track through time the characteristics, interactions and activities of every individual in the community. The modelling framework is flexible and thus also extendable to other avenues of research