Impact of Extreme Precipitation Events on the Water Table and Groundwater Recharge

Extreme precipitation events (EPEs) play a crucial role in influencing soil water storage and groundwater recharge worldwide. With climate change, extreme precipitation events are expected to increase in intensity, creating an urgent need to examine their effects on water resources. On the land surface, the wide-ranging impacts of EPEs are visible. These impacts can be described as destructive, causing mass flooding, property damage and putting lives at risk. Below the surface however, the impacts of EPEs on subsurface processes are less clear and warrant urgent study. In this dissertation, I examine the impacts of extreme precipitation events on water table mechanics and groundwater recharge. I begin my study locally, by investigating the role of an extreme precipitation event that occurred along the Colorado Front Range in September 2013. The event quickly caused widespread flooding, but flood waters diminished just as quickly. For many years, it remained unclear whether that EPE-water had infiltrated the soil and if so, for how long the EPE-water may have impacted local soil water storage and water tables. My first goal was thus to examine the subsurface hydrologic response to the 2013 Colorado EPE using an unsaturated-flow model and field data from a site that had experienced the event. I find that after the EPE, the water table at a field site remained elevated relative to average water levels, for at least 18 months after the event, while the soil water storage was higher than average for two water years after the event. Thus, infiltration from EPEs is present for much longer than flood waters, and may aid recharge. Having investigated the subsurface response to an EPE at a site, the next step was to expand the study to examine whether similar responses occurred across varying soil texture classes and EPEs for other sites in the United States. I find that greater EPE amounts generally lead to higher water-table displacements, but that soil properties are also a strong control of displacement and determine the length of time needed for the water-table to recede after an EPE. Finally, I conduct a comprehensive, model-based study in which I investigate the response of twelve different soil texture classes to EPEs of varying amounts and durations. Water-table response times are shorter with increasing EPE amount, and that water-table response occurs much faster in coarser-grained soils (i.e., sand), while taking upwards of hundreds of days to respond in finer-grained soils. Water-table displacement is positively correlated with increasing EPE amount and poorly correlated with longer EPE duration. Soil properties appear to be the greater control in water-table recession time, despite EPE amounts. Finally, I calculated first-order recharge rates and found average recharge equaled 70% of the total, with the amount of total recharge primarily controlled by the amount of the EPE and the soil properties. In summary, EPEs replenish subsurface water storage, but water-table displacement and prolonged recession could be detrimental for ground stability.</p

Desafíos y tendencias del México actual

Conjunto de once ensayos cuyo propósito es suscitar la reflexión sobre las tendencias más importantes que marcan el inicio del siglo XXI en México y Jalisco, sin obviar las direcciones que a escala mundial toman la vida social, política y económica.ITESO, A.C

Celulosa y microcelulosa de residuos del cultivo de caña de azúcar (Saccharum spp.)

Objective: To characterize the structure, texture and thermal properties of cellulose and cellulose microfibers (MFC) of three sugarcane crops and the development of a biocomposite. Design / methodology / approach: The celluloses were extracted by the Kraft method and the MFCs of the cultures MEX-69-290, CP-72-2086 and MEX-68-P23, using oxidative and mechanical processes; for its characterization spectroscopic, microscopic and thermal techniques were used; and were analyzed with a completely randomized design, where the treatments were cellulose and CFM extracted from the three cultivars of sugarcane; In addition to the fusion processing of a biocomposite from polylactic acid and CMF. Results: Cellulose and CFM were obtained from the straw of the three crops, the similar quality, the percentage of moisture in the straw and the cellulose having the same behavior, the chemical composition of the cellulose is of high purity. The results of XRD and FTIR have characteristic bands and similar amounts of cellulose in the crystalline phase. TGA indicates that cellulose decomposes at higher temperatures of polylactic acid (PLA), which supports melt mixing processes. Limitations of the study / implications: The varieties of sugarcane pajamas have different characteristics in the cellulose phase and in the CFM phase; but similar between cultivars. Findings / conclusions: The crystallinity by XRD and the identification of functional groups by FTIR show us characteristic bands of the cell in the crystalline phase and how the amorphous part of the straw is lost without treatment, becoming more crystalline when it becomes cellulose and mostly in microcellulose; as well as the similarity that exists in the three cultivars of said components and in similar quantities. The resistance properties of the biocomposite will be affected when the CFMs are added to the polylactic acid.Objetivo: Caracterizar la estructura, textura y propiedades térmicas de celulosas y microfibras de celulosa (MFC) de tres cultivares de caña de azúcar y la elaboración de un biocompuesto. Diseño/metodología/aproximación: Las celulosas fueron extraídas por el método Kraft y las MFC de los cultivares MEX-69-290, CP-72-2086 y MEX-68-P23, utilizando procesos oxidativos y mecánicos; para su caracterización se emplearon técnicas espectroscópicas, microscópicas y térmicas; y fueron analizadas con un diseño completamente al azar, donde los tratamientos fueron la celulosa y MFC extraídas de los tres cultivares de caña de azúcar; además de la elaboración por fusión de un biocompuesto a partir de ácido poliláctico y las MCF. Resultados: Se obtuvieron celulosa y MFC de la paja de los tres cultivares, la cual presentó similitud, teniendo el mismo comportamiento el porcentaje de humedad en la paja y la celulosa, la composición química de la celulosa es de alta pureza. Los resultados de XRD y FTIR presentan bandas características y cantidades similares de celulosa en fase cristalina. TGA indica que la celulosa se descompone a temperaturas más altas de ácido poliláctico (PLA), lo que apoya los procesos de mezcla en fusión. Limitaciones del estudio/implicaciones: Las variedades de paja de caña de azúcar presentan características diferentes en la fase de celulosa y en fase de MFC; pero similar entre cultivares. Hallazgos/conclusiones: La cristalinidad mediante XRD y la identificación de grupos funcionales por FTIR nos muestran bandas características de celulosa en fase cristalina y cómo se va perdiendo la parte amorfa de la paja sin tratamiento, volviéndose más cristalina al convertirse en celulosa y mayormente en microcelulosa; así como también la similitud que existe en las tres cultivares de dichos componentes y en cantidades semejantes. Las propiedades de resistencia del biocompuesto se vieron afectadas cuando las MFC´s se agregaron al ácido poliláctico

Mapping and assessment of forest ecosystems and their services - Applications and guidance for decision making in the framework of MAES

The aim of this report is to illustrate by means of a series of case studies the implementation of mapping and assessment of forest ecosystem services in different contexts and geographical levels. Methodological aspects, data issues, approaches, limitations, gaps and further steps for improvement are analysed for providing good practices and decision making guidance. The EU initiative on Mapping and Assessment of the state of Ecosystems and their Services (MAES), with the support of all Member States, contributes to improve the knowledge on ecosystem services. MAES is one of the building-block initiatives supporting the EU Biodiversity Strategy to 2020.JRC.H.3-Forest Resources and Climat

TRY plant trait database – enhanced coverage and open access

Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

How culturally unique are pandemic effects? Evaluating cultural similarities and differences in effects of age, biological sex, and political beliefs on COVID impacts

Despite being bio-epidemiological phenomena, the causes and effects of pandemics are culturally influenced in ways that go beyond national boundaries. However, they are often studied in isolated pockets, and this fact makes it difficult to parse the unique influence of specific cultural psychologies. To help fill in this gap, the present study applies existing cultural theories via linear mixed modeling to test the influence of unique cultural factors in a multi-national sample (that moves beyond Western nations) on the effects of age, biological sex, and political beliefs on pandemic outcomes that include adverse financial impacts, adverse resource impacts, adverse psychological impacts, and the health impacts of COVID. Our study spanned 19 nations (participant N = 14,133) and involved translations into 9 languages. Linear mixed models revealed similarities across cultures, with both young persons and women reporting worse outcomes from COVID across the multi-national sample. However, these effects were generally qualified by culture-specific variance, and overall more evidence emerged for effects unique to each culture than effects similar across cultures. Follow-up analyses suggested this cultural variability was consistent with models of pre-existing inequalities and socioecological stressors exacerbating the effects of the pandemic. Collectively, this evidence highlights the importance of developing culturally flexible models for understanding the cross-cultural nature of pandemic psychology beyond typical WEIRD approaches

Investigation of hospital discharge cases and SARS-CoV-2 introduction into Lothian care homes

Background The first epidemic wave of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in Scotland resulted in high case numbers and mortality in care homes. In Lothian, over one-third of care homes reported an outbreak, while there was limited testing of hospital patients discharged to care homes. Aim To investigate patients discharged from hospitals as a source of SARS-CoV-2 introduction into care homes during the first epidemic wave. Methods A clinical review was performed for all patients discharges from hospitals to care homes from 1st March 2020 to 31st May 2020. Episodes were ruled out based on coronavirus disease 2019 (COVID-19) test history, clinical assessment at discharge, whole-genome sequencing (WGS) data and an infectious period of 14 days. Clinical samples were processed for WGS, and consensus genomes generated were used for analysis using Cluster Investigation and Virus Epidemiological Tool software. Patient timelines were obtained using electronic hospital records. Findings In total, 787 patients discharged from hospitals to care homes were identified. Of these, 776 (99%) were ruled out for subsequent introduction of SARS-CoV-2 into care homes. However, for 10 episodes, the results were inconclusive as there was low genomic diversity in consensus genomes or no sequencing data were available. Only one discharge episode had a genomic, time and location link to positive cases during hospital admission, leading to 10 positive cases in their care home. Conclusion The majority of patients discharged from hospitals were ruled out for introduction of SARS-CoV-2 into care homes, highlighting the importance of screening all new admissions when faced with a novel emerging virus and no available vaccine

SARS-CoV-2 Omicron is an immune escape variant with an altered cell entry pathway

Vaccines based on the spike protein of SARS-CoV-2 are a cornerstone of the public health response to COVID-19. The emergence of hypermutated, increasingly transmissible variants of concern (VOCs) threaten this strategy. Omicron (B.1.1.529), the fifth VOC to be described, harbours multiple amino acid mutations in spike, half of which lie within the receptor-binding domain. Here we demonstrate substantial evasion of neutralization by Omicron BA.1 and BA.2 variants in vitro using sera from individuals vaccinated with ChAdOx1, BNT162b2 and mRNA-1273. These data were mirrored by a substantial reduction in real-world vaccine effectiveness that was partially restored by booster vaccination. The Omicron variants BA.1 and BA.2 did not induce cell syncytia in vitro and favoured a TMPRSS2-independent endosomal entry pathway, these phenotypes mapping to distinct regions of the spike protein. Impaired cell fusion was determined by the receptor-binding domain, while endosomal entry mapped to the S2 domain. Such marked changes in antigenicity and replicative biology may underlie the rapid global spread and altered pathogenicity of the Omicron variant