Bayesian hierarchical models for analysing the spatial distribution of bioclimatic indices

A methodological approach for modelling the spatial distribution of bioclimatic indices is proposed in this paper. The value of the bioclimatic index is modelled with a hierarchical Bayesian model that incorporates both structured and unstructured random effects. Selection of prior distributions is also discussed in order to better incorporate any possible prior knowledge about the parameters that could refer to the particular characteristics of bioclimatic indices. MCMC methods and distributed programming are used to obtain an approximation of the posterior distribution of the parameters and also the posterior predictive distribution of the indices. One main outcome of the proposal is the spatial bioclimatic probability distribution of each bioclimatic index, which allows researchers to obtain the probability of each location belonging to different bioclimates. The methodology is evaluated on two indices in the Island of Cyprus.Peer Reviewe

Physical performance and durability evaluation of rubberized concrete

The main objective of this research is to develop rubberized concrete with achievable structural strength using simple mix design. Simple mix design is a description by using the crumb rubber, used as in condition just received from the plant without any washing or pre-treating procedure. Then, three types of durability test were conducted namely, 1) Chloride ion diffusion test, 2) Abrasion wear resistance test, and 3) Freezing and thawing test. Up-to-date, many successful achievements were reported by researchers around the world. However, in Asian cases, very rare information on the use of wasted as a mixture component is gathered. By conducting this study, it could provide useful and valuable knowledge for construction technology especially for Asian industry. This dissertation consists mainly of the seven chapters. In Chapter 1, the background, problem statement, significance, research contribution and novelty of this study are listed out. In Chapter 2, research review on previous researchers work on the application of waste tire rubber in mortar/concrete and durability are described. Several important properties related to this study were viewed and discussed. High reduction in strength properties was observed by previous researchers and many suggestions were proposed either by washing the rubber or the use of suitable treatment on the rubber surface in order to enhance the bonding of the matrix. However, in my research, by using conventional mixing method, it was proposed that to use the rubber without any treatment (use directly as received) with maximum 20% sand replacement in volume is a method to use crumb rubber effectively. As a result, each rubberized mixture showed an acceptable structural strength value. In Chapter 3, three step-by-step stages of mix design were conducted and discussed. The first stage was the preliminary study to determine the suitable waste tire rubber size and percentage replacement that can be used in rubberized mortar. Three rubber size group were received from the industry plant which where combination of 1mm-3mm, combination of 0.71mm-1.7mm and 0.425mm. Size of 1mm – 3mm with 10% of sand replacement was chosen in terms of acceptable fresh and hardened mortar properties. In second stage, suitable water-to-cement ratio (w/c) and required additional binder was determined before proceeding to concrete mix. Results shows that w/c = 0.35 gave reliable mortar physical properties. Finally, rubberized concrete with w/c =0.35 was carried out and specimens were prepared for mechanical test and durability test. Along these three stages, air content was carefully studied and controlled. In Chapter 4, experimental work and discussion on chloride ion diffusion in rubberized concrete tested by migration test and by immersion in salt water was described. Effective diffusion coefficient, De test was conducted according to JSCE-G571-2003. Meanwhile, immersion test in salt water was conducted according to JSCE-G572-2003. Additional concrete specimen with w/c = 0.50 was prepared to study the effectiveness of CR in high w/c in comparison with w/c = 0.35. Results showed that chloride transport characteristics were improved by increasing the amount of CR due to the fact that CR has the ability to repel water. Meanwhile, rubberized concrete with w/c = 0.35 gave better resistance against chloride ion compared to w/c = 0.50. In Chapter 5, discussion on the effectiveness of crumb rubber to improve wear resistance tested by surface abrasion test was described. An experimental study on abrasion wear resistance was conducted on mortar (w/c = 0.35, 0.30 and 0.25) and concrete (w/c = 0.35) specimen containing CR with and without silica fume. From test results, it was clearly seen that 10% crumb rubber addition as sand replacement provide good resistance against abrasion. Meanwhile, compressive strength was the most important factor affecting the abrasion resistance, where abrasion resistance was increased with an increase in compressive strength. However, abrasion resistance was found to be slightly decreased when compressive strength exceeds 50N/mm2. In Chapter 6, the role of crumb rubber as air void under freezing and thawing was studied. Specimen was prepared in three groups; first group was the specimen without silica fume with air content ranging between 4% to 5%, second group was the specimen without silica fume with air content ranging between 0% to 1.5% and third group was the specimen with silica fume with air content ranging between 4% to 5%. These rubberized concrete were tested on freezing and thawing resistance to understand this behavior. The temperature for freezing and thawing was set to 15oC ±5oC for thawing temperature and -18oC ±5oC for freezing. This test was continued until 300 cycles according to ASTM C666. Results show that up to 300 freeze-thaw cycle, there was no minus effect observed for all specimen. In Chapter 7, conclusions are drawn based on Chapter 4 to Chapter 6 and recommendations for future works is presented

Invasion success of a global avian invader is explained by within-taxon niche structure and association with humans in the native range

Aim To mitigate the threat invasive species pose to ecosystem functioning, reli- able risk assessment is paramount. Spatially explicit predictions of invasion risk obtained through bioclimatic envelope models calibrated with native species distribution data can play a critical role in invasive species management. Fore- casts of invasion risk to novel environments, however, remain controversial. Here, we assess how species’ association with human-modified habitats in the native range and within-taxon niche structure shape the distribution of invasive populations at biogeographical scales and influence the reliability of predictions of invasion risk. Location Africa, Asia and Europe. Methods We use ~1200 native and invasive ring-necked parakeet (Psittacula krameri) occurrences and associated data on establishment success in combi- nation with mtDNA-based phylogeographic structure to assess niche dynam- ics during biological invasion and to generate predictions of invasion risk. Niche dynamics were quantified in a gridded environmental space while bioclimatic models were created using the biomod2 ensemble modelling framework. Results Ring-necked parakeets show considerable niche expansion into climates colder than their native range. Only when incorporating a measure of human modification of habitats within the native range do bioclimatic envelope mod- els yield credible predictions of invasion risk for parakeets across Europe. Inva- sion risk derived from models that account for differing niche requirements of phylogeographic lineages and those that do not achieve similar statistical accu- racy, but there are pronounced differences in areas predicted to be susceptible for invasion. Main conclusions Information on within-taxon niche structure and especially association with humans in the native range can substantially improve predic- tive models of invasion risk. To provide policymakers with robust predictions of invasion risk, including these factors into bioclimatic envelope models is recommended

Potential future climatic conditions on tourists : a case study focusing on Malta and Venice

The main purpose of this study is to quantify important climatic shifts that took place over Malta and Venice that could be considered as a determining factor on their choice as two prime tourist destinations. Rather than making use of traditional tourist climate indices, this study identifi es long-term trends in weather variables and their derived bioclimatic indices. These climate derivatives are based on a set of high temporal observations (some of which are collected every 30 minutes) and are thus able to capture valuable information that traditional monthly distribution cannot provide. The derivatives obtained from the elementary meteorological observations showed that the level of comfort experienced by visiting tourists over the long term is deteriorating due to increased heat stress. Nonetheless, the increased occurrence of optimal wind speed conditions, as well as a reduced occurrence of gale storms and wind chill events is making these destinations more attractive. A careful study of the output of IPCC climate model projections sheds light on a critical future bioclimate condition during current peak visiting months (July and August) at both destinations. This may imply a required shift, as a form of adaptation, of the visiting periods at these two destinations. This study should allow tourist planners to determine which weather element is a likely future obstacle to the overall bioclimatic suitability of outdoor tourism activities.peer-reviewe

Evolution of microgastropods (Ellobioidea, Carychiidae): integrating taxonomic, phylogenetic and evolutionary hypotheses

BACKGROUND: Current biodiversity patterns are considered largely the result of past climatic and tectonic changes. In an integrative approach, we combine taxonomic and phylogenetic hypotheses to analyze temporal and geographic diversification of epigean (Carychium) and subterranean (Zospeum) evolutionary lineages in Carychiidae (Eupulmonata, Ellobioidea). We explicitly test three hypotheses: 1) morphospecies encompass unrecognized evolutionary lineages, 2) limited dispersal results in a close genetic relationship of geographical proximally distributed taxa and 3) major climatic and tectonic events had an impact on lineage diversification within Carychiidae. RESULTS: Initial morphospecies assignments were investigated by different molecular delimitation approaches (threshold, ABGD, GMYC and SP). Despite a conservative delimitation strategy, carychiid morphospecies comprise a great number of unrecognized evolutionary lineages. We attribute this phenomenon to historic underestimation of morphological stasis and phenotypic variability amongst lineages. The first molecular phylogenetic hypothesis for the Carychiidae (based on COI, 16S and H3) reveals Carychium and Zospeum to be reciprocally monophyletic. Geographical proximally distributed lineages are often closely related. The temporal diversification of Carychiidae is best described by a constant rate model of diversification. The evolution of Carychiidae is characterized by relatively few (long distance) colonization events. We find support for an Asian origin of Carychium. Zospeum may have arrived in Europe before extant members of Carychium. Distantly related Carychium clades inhabit a wide spectrum of the available bioclimatic niche and demonstrate considerable niche overlap. CONCLUSIONS: Carychiid taxonomy is in dire need of revision. An inferred wide distribution and variable phenotype suggest underestimated diversity in Zospeum. Several Carychium morphospecies are results of past taxonomic lumping. By collecting populations at their type locality, molecular investigations are able to link historic morphospecies assignments to their respective evolutionary lineage. We propose that rare founder populations initially colonized a continent or cave system. Subsequent passive dispersal into adjacent areas led to in situ pan-continental or mountain range diversifications. Major environmental changes did not influence carychiid diversification. However, certain molecular delimitation methods indicated a recent decrease in diversification rate. We attribute this decrease to protracted speciation

Comparación de técnicas de clasificación deductivas para estimar la distribución potencial de insectos cuarentenarios

El objetivo de este trabajo fue comparar el desempeño de los criterios de clasificación nítidos y difusos en la construcción de modelos deductivos de la distribución potencial de insectos exóticos. Considerando criterios de clasificación binaria nítida y difusa, de capas ráster de temperatura máxima, media y mínima diaria, se generó un índice de riesgo bioclimático relativo, considerando el número de días con condiciones óptimas para el desarrollo de Bactrocera oleae (Gmelin) (Diptera: Tephritidae) y Cerotoma arcuatus (Olivier) (Coleoptera: Chrysomelidae). Se realizaron análisis de sensibilidad de los modelos. Los modelos deductivos de distribución potencial de especies realizados mediante clasificación difusa, serían más robustos y menos restrictivos en la determinación de áreas de riesgo fitosanitario potencial que aquellos realizados con criterios de clasificación nítidos. Estos últimos serían más sensibles y tendrían mayor capacidad de discriminar áreas con diferentes perfiles de riesgo ambiental.The objective of this paper was to evaluate the performance of crisp and fuzzy classification criteria in the construction of deductive potential distribution models of exotic insects. As case studies, Bactrocera oleae (Gmelin) (Diptera: Tephritidae) and Cerotoma arcuatus (Olivier) (Coleoptera: Chrysomelidae) were selected. Considering crisp and fuzzy classification for raster layers of maximum, average and minimum daily temperature, a relative bioclimatic risk index was generated. The number of days with optimal conditions for pests’ development was considered. Sensitivity analyses of both models were performed. Considering each case evaluated and the variables used, deductive pest distribution models made by fuzzy classification was more robust and less conservative in the determination of potential phytosanitary risk areas than those made with crisp classification criteria. This last case was more sensitive and would have a greater capacity to discriminate areas with different environmental risk profiles.Fil: Heit, Guillermo Eugenio. Universidad de Buenos Aires. Facultad de Agronomia. Departamento de Producción Vegetal. Cátedra de Zoología Agrícola; ArgentinaFil: Sione, Walter Fabian. Universidad Autónoma de Entre Rí­os. Facultad de Ciencia y Tecnología. Centro Regional de Geomática; Argentina. Universidad Nacional de Luján; ArgentinaFil: Claps, Lucia Elena. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto Superior de Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aceñolaza, Pablo Gilberto. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentin