This article addresses the question: What is expected from frazil ice activity in rivers, taking into account the changing climate? It begins with an overview of what frazil ice is and what is required for the occurrence of frazil ice events, namely a supercooled water column. Methodologies to anticipate frazil ice events in the short term are based on air temperature and water discharge, underlining the significance of these two parameters for any predictive methods. Longer-term approaches, calibrated against past events (hindcasting), are used to anticipate frazil ice activity into the future, with indicators such as frazil ice risk, water temperature and frazil volume. Any of these approaches could conceivably be applied to frazil-prone river stretches. To assess climate impact, each location should be treated separately. River ice dynamics can lead to the formation of a hanging dam, a frequent outcome of frazil ice generation in the early winter, causing flow restriction. Flood modeling and forecasting capabilities have been developed and implemented for operational use. More frequent mid-winter breakups are expected to extend the occurrence of frazil ice events into the winter months – the prediction of these will require climate model output to adequately capture month-to-month variability.
HIGHLIGHTS
Previous modeling endeavors aimed at foreseeing frazil ice generation in rivers are summarized.;
Frazil ice risk, water temperature and frazil ice volume are model outputs.;
Each frazil-prone location should be the subject of its own climate impact study.;
Mid-winter breakups (MWBs) will likely be more frequent in the future, which implies that clogging risks at water intakes will extend well into the winter months.;
River, lake, and water-supply engineering (General), Physical geography
Como en otras regiones americanas, en Colombia la tecnología lítica ha ocupado un lugar central a la hora de documentar y caracterizar las ocupaciones humanas antes de la aparición de la alfarería. El objetivo del presente artículo es hacer una revisión de dos temas de la arqueología temprana colombiana mirados desde la tecnología lítica. El primero, el poblamiento pleistoceno de Colombia. En este apartado se analiza la relación de la tecnología lítica con las estrategias de subsistencia, y con potenciales movimientos démicos en el Noroccidente de Suramérica durante el Tardiglacial. El segundo, los cambios adaptativos relacionados con la llegada del Holoceno. En esta segunda parte, se analizan cambios en las estrategias de subsistencia, a partir del análisis de las azadas, uno de los artefactos más representativos de la geografía colombiana, vinculado al uso temprano de plantas y a los orígenes de su cultivo.
Romulus Costache, Hazem Ghassan Abdo, Arun Pratap Mishra
et al.
AbstractIn this work, the vulnerability to flooding in the Prahova River basin was calculated and analyzed using advanced methods and techniques. Thus, 2 hybrid models represented by Iterative Classifier Optimizer – Multiclass Alternating Decision Tree – Certainty Factor (ICO-LADT-CF) and Fuzzy-Analytical Hierarchy Process – Certainty Factor (FAHP-CF) were generated, which had as input data the values of 10 flood predictors and a number of 158 points where historical floods occurred. In the first step, the Certainty Factor values were calculated, which were then used in the Fuzzy-Analytical Hierarchy Process and Multiclass Alternating Decision Tree models. It should be mentioned that the Multiclass Alternating Decision Tree model was optimized with the help of the Iterative Classifier Optimizer. In the case of both ensemble models the slope angle was the most important flood conditioning factor. Moreover, according to Certainty Factor modelling the 8 classes/categories achieved the maximum value of 1. Next, the susceptibility to floods on the surface of the study area was derived. On average, about 20% of the study area has areas with high and medium susceptibility to flash floods. After evaluating the quality of the models through Receiver Operating Characteristics (ROC) Curve, the following results emerged: Success Rate for Flood Potential Index (FPI) Iterative Classifier Optimizer – Multiclass Alternating Decision Tree – Certainty Factor (ICO-LADT-CF) (Area Under Curve = 0.985) and Flood Potential Index (FPI) Fuzzy-Analytical Hierarchy Process – Certainty Factor (FAHP-CF) (Area Under Curve = 0.967); Prediction Rate for Flood Potential Index (FPI) Iterative Classifier Optimizer – Multiclass Alternating Decision Tree – Certainty Factor (ICO-LADT-CF) (Area Under Curve = 0.952) and Flood Potential Index Fuzzy-Analytical Hierarchy Process – Certainty Factor (FAHP-CF) (Area Under Curve = 0.913). At the same time, the accuracies of the models were: Training dataset − 0.943 (Iterative Classifier Optimizer – Multiclass Alternating Decision Tree – Certainty Factor) and 0.931 (Fuzzy-Analytical Hierarchy Process – Certainty Factor); Validating dataset − 0.935 (Iterative Classifier Optimizer – Multiclass Alternating Decision Tree – Certainty Factor) and 0.926 (Fuzzy-Analytical Hierarchy Process – Certainty Factor). As main conclusion, it can be mentioned that the 2 ensemble models outperform the previous machine learning models applied on the same study area before.
Attention is increasingly being paid to the influence of hinterland cities on port competitiveness, but in-depth research is lacking on the formation conditions and mechanism of hinterland cities’ influence on port competitiveness. Based on the technology–organization–environment (TOE) framework and the characteristics of Chinese government organizational behavior, in this study, we used fuzzy-set qualitative comparative analysis (fsQCA) to conduct a condition configuration analysis of 21 coastal ports and their hinterland cities in China. The findings showed the following: (1) The technology, organization, and environment conditions of hinterland cities cannot provide the necessary conditions for high or low port competitiveness alone: different combinations of these conditions have produced three high and four low port competitiveness configurations. (2) The three configurations of high port competitiveness are the organization–environment, economy–balance, and finance–balance types. Adequate government financial supply, high tertiary industry proportion, good economic development, and market openness are the core conditions required for achieving high port competitiveness. (3) The four configurations of low port competitiveness are finance–facilities–environment, capability–finance–environment, technology–finance–economy, and capability–industry–economy restrictions. Here, low-level innovation capability, inadequate government financial supply, and low tertiary industry proportion are the core conditions leading to low port competitiveness. We revealed the concurrent synergistic effect of the three conditions of technology, organization, and environment in hinterland cities and demonstrated the causal complexity and asymmetry of the impact of hinterland cities on port competitiveness. Our conclusions provide empirical evidence that will aid hinterland cities in formulating differentiated port competitiveness promotion policies according to their own conditions and endowments.
Abstract Terrestrial records of the last geomagnetic reversal often have few age constraints. Chronostratigraphy using suborbital-scale paleoceanic events during marine isotope stage 19 may contribute to solving this problem. We applied the method to an 8 m long, high-resolution paleomagnetic record from a loess sequence in China and revealed millennial-to-sub-centennial scale features of the Matuyama–Brunhes (MB) transition. All samples were subjected to progressive thermal demagnetization with 14–15 steps up to 650–680 °C. As a result, 96% of the samples yielded a high-quality remanent magnetization. The MB transition terminated with a 75 cm thick zone with nine polarity flips. The polarity flip zone, dated at about 779–777 ka, began between the warm events “I” and “J” and terminated at the end of the cooling event coincident with the lowest axial-dipole strength interval. Most polarity flips occurred within 70 years. The virtual geomagnetic poles (VGPs) in the upper polarity flip zone clustered in the SW Pacific region, where the MB transitional VGPs from lavas of the Hawaiian and Canary Islands and lacustrine deposits of Java also clustered. These sites were probably dominated by dipolar fields. The absence of transitional fields across polarity flips implies a short time span for averaging fields due to a thin loess-magnetization lock-in zone. The reverse-to-normal polarity reversal dated at about 778 ka in Lingtai occurred at the end of the SW Pacific VGP zone, an important key bed for MB transition stratigraphy. The reversal is a good candidate for the main MB boundary. We found an excursion at about 766 ka spanning about 1 ka.
Marleen C. deRuiter, Anaïs Couasnon, Marc J. C. van denHomberg
et al.
Abstract In recent decades, a striking number of countries have suffered from consecutive disasters: events whose impacts overlap both spatially and temporally, while recovery is still under way. The risk of consecutive disasters will increase due to growing exposure, the interconnectedness of human society, and the increased frequency and intensity of nontectonic hazard. This paper provides an overview of the different types of consecutive disasters, their causes, and impacts. The impacts can be distinctly different from disasters occurring in isolation (both spatially and temporally) from other disasters, noting that full isolation never occurs. We use existing empirical disaster databases to show the global probabilistic occurrence for selected hazard types. Current state‐of‐the art risk assessment models and their outputs do not allow for a thorough representation and analysis of consecutive disasters. This is mainly due to the many challenges that are introduced by addressing and combining hazards of different nature, and accounting for their interactions and dynamics. Disaster risk management needs to be more holistic and codesigned between researchers, policy makers, first responders, and companies.
Die Frage, ob und wenn ja wie mit Rechten zu reden wäre, ist gegenwärtig einigermaßen prominent. Dass der Versuch, rechte Akteure argumentativ umzustimmen oder zu überzeugen, wenig erfolgversprechend ist, hat sich zudem herumgesprochen. Doch was heißt das für die Forschung? Der Beitrag diskutiert kritisch die Möglichkeiten und Grenzen empirischer Sozialforschung an und mit Rechten. Einerseits zeigt sich, dass die Forschung möglicherweise nur Wissensbestände aktualisiert, die schon bekannt sind. Und andererseits könnte es aufgrund der sich rasant verändernden technischen, sozialen und kulturellen Rahmenbedingungen wichtig sein, der Theorie mehr Gehör zu schenken und den Versuch zu starten, die überlieferten theoretischen Kategorien zu überdenken.
Cities. Urban geography, Urban groups. The city. Urban sociology
Equitable provision of health care services and full coverage of health accessibility are the major challenge for developing countries to achieve the sustainable development goal (SDG 3 and 10). A geographical information system (GIS) is an effective platform for knowing how much area and population are covered by the existing MCH (maternal child health) services network for better health care planning. The aim of this study is to assess the geographical accessibility of MCH services and how they give impact on infant mortality and fertility in Sagar District. To uncover the answer, this study used buffer zone analysis, service area analysis, and multiple regression analysis.
The findings highlight lower accessibility has prevailed in the study area in which 41 percent village was underserved by the buffer zone analysis while 62 percent was underserved by the service area analysis out of 2075 village. It is diversified from higher accessibility in north western Khurai plain region to lower in the central upland exclude the Sagar community development Block. We also find that health accessibility can explain 53 percent of the infant mortality of the district and IMR may control 33 percent of the children ever born in the district.
The service area and buffer mapped output may have policy implication for the future establishment of the health center and road network. This policy can be helpful for reducing infant mortality and fertility through this they achieved SDG target.
.أن للاتزان في دراسة حركة الاجسام اثناء الاداء الرياضي حيث ان الاتزان الثابت والمتحرك يدخل ضمن الكثير من الفعاليات وتتأثر بالقوة الخارجية خلال ذلك الاداء وتختلف حسب نوع الفعالية لذلك ان التدريب وفق عبئ مسلط على عضلات معينة لم يتم الاهتمام بتدريبها بشكل خاص اثناء التمرينات التقليدية وفعالية 110م حواجز من اهم الفعاليات التي تتطلب اهتماما بجانب القدرات البدنية الخاصة المتمثلة بعضلات تعمل حسب خصوصية الاداء والمتغيرات البايوميكانيكية لكل خطوة اجتياز كما ان دراسة العزوم والزخوم من المتغيرات التي لم يتطرق لها الكثير من الباحثين في فعاليات الحواجز، لذلك ارتأت الباحثة استخدام تدريبات الاتزان بأدوات تدخل ضمن تمرينات لعدائي 110م حواجز وتأثير هذه التدريبات في العزوم والزخوم اللحظية لخطوة اجتاز الحاجز لمراحل مختلفة للحواجز 1-5-10 والانجاز وتم تطبيق هذه التدريبات على عينة من (8) عدائين من النخبة وقد لاحظت الباحثة ان تطور متغيرات البحث البايوميكانيكية من عزم لحظي في الاقتراب والدفع لحظة الارتكاز قبل الحاجز وزخم لحظي في الاقتراب والدفع وفرق الزخوم قد تأثرت بشكل كبير في الاختبار البعدي عما كانت عليه النتائج في الاختبار القبلي ولقد اثرت هذه المتغيرات في زمن اجتياز الحاجز 1-5-10 وبالتالي زمن انجاز110م حواجز للشباب.
The increased frequency and intensity of droughts is a challenging phenomenon for humankind, its impact on developing nations has increased significantly. Marathwada region is chronically prone to drought and has been impacted severely between the years 2012 to2016. The paper attempts to make a spatio-temporal analysis of drought events in the Marathwada region. Three drought indices, namely Rainfall Anomaly Index (RAI), Standardized Water level Index (SWI) and NDVI Anomaly Index (NAI) were used for meteorological, hydrological and agricultural drought analysis. This study is mainly based on the secondary data sources along with field-based observation. The analysis revealed that eteorological drought events are not new for the Marathwada region. The Marathwadaregion has witnessed the worst hydrological drought in the year 2015. The correlation analysis shows that meteorological drought is directly followed by hydrological drought without any lag. The NDVI Anomaly Index of the year 2015 revealed a prevalence of agricultural drought while the results of crop Yield Anomaly Index of principal crops of region validates the outcomes of NDVI Anomaly Index.
Danny A. Villegas, César O. Acosta, Manuel E. Mi E Milla
El presente trabajo tiene como objetivo evaluar el crecimiento de plantas de pimentón (<em>Capsicum annuum</em> L.) en condiciones controladas bajo el efecto de <em>Trichoderma</em> <em>harzianum</em> Rifai. Para lo cual se consideraron modelos no lineales, entre ellos: logístico y gompertz. El ensayo se realizó en Casas de Cultivos bajo condiciones controladas aplicando un diseño de tratamiento (dos tratamientos y tres (3) repeticiones). Tratamiento T1: Aplicación de una dosis del hongo <em>Trichoderma</em> de 100 gr. antes de la siembra. Tratamiento T2: Aplicación de una dosis del hongo <em>Trichoderma</em> de 100 gr. después de la siembra. Se midieron las siguientes variables: longitud de la planta (cm), diámetro del tallo (cm) y área foliar (cm<sup>2</sup>) cada 15 días a partir del momento del trasplante. Los resultados arrojaron que el modelo logístico debe ser considerado únicamente para ajustar datos de altura de plantas de pimentón a las que se les aplicó una dosis del hongo <em>Trichoderma</em> antes de la siembra, mientras que para el resto de las variables y demás condiciones experimentales se aconseja utilizar el modelo gompertz. Así mismo, cuando se aplicó una dosis del hongo <em>Trichoderma</em> a las plantas de pimentón antes de la siembra se evidenció una mayor tasa intrínseca de crecimiento, un menor crecimiento máximo y las plantas tardaron más tiempo en desacelerar el crecimiento en altura pero menos tiempo en desacelerar el desarrollo del área foliar. Mientras que cuando se aplicó una dosis del hongo <em>Trichoderma</em> después de la siembra las plantas reportaron una mayor tasa intrínseca de crecimiento, un menor crecimiento máximo tardaron menos tiempo en desacelerar el crecimiento en diámetro
David E. Reed, Hilary A. Dugan, Amelia L. Flannery
et al.
Abstract Recent research has shown lakes play an outsized role in carbon cycling, but long‐term continuous observations and analysis of carbon dynamics are rare, limiting our understanding of interannual variation, important timescales of variability, and drivers of efflux. Therefore, we examined lake‐atmosphere carbon fluxes with the goal of quantifying annual trends and patterns in lake carbon efflux and identifying important timescales. To do so, this study integrated 6 yr of eddy‐covariance flux tower observations of lake‐atmosphere fluxes with high‐frequency observations of in‐lake temperature, dissolved oxygen, and partial pressure of CO2, for a eutrophic lake in Wisconsin, U.S.A. While growing season fluxes are variable and switch between source and sink, annual net carbon fluxes show the lake acts as an annual sink of carbon, with the magnitude depending on climate, along with the timing and strength of fall turnover, with half of the total annual carbon uptake happening in October and November.