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To investigate long-term relationships between climate, vegetation, landscape geochemistry and fires in the boreal forest zone of Western Siberia, a sediment core of 345 cm was collected from Shchuchye Lake (located in south taiga zone of southeast part of West Siberian plain) and investigated by spore-pollen, radiocarbon, LOI and charcoal analyses. Quantitative palaeoclimate was reconstructed based on pollen data. Investigation revealed 13.2 cal ka history of vegetation, climate, landscapes and fires. In the dry climate of Late Glacial, the landscape was treeless. Continuous permafrost existed in the soil. In the middle of the YD cooling 12.4–12.2 cal ka BP, our data showed warming that caused degradation of permafrost in soils and settlement of spruce in moist places. Later, thawing and accumulation of moisture in a local lowering in relief increased and a lake was formed. With the beginning of the Holocene, the climate sharply changed to warmer and wetter. Intensified surface flow caused accumulation of mineral and carbonate fraction in the lake. Dense birch forests spread on drylands. As a result, the leaching regime initiated the formation of podzols in the soil. At about 10.0 cal ka BP, Scots pine (Pinus sylvestris) quickly spread in the area of investigation. Fires became more frequent and more intense during the dry Late Glacial time, sharply decreasing with increased precipitation in the Early Holocene, and again moderately increasing with spread of pine forests in the mid Holocene. With the transition to Late Holocene (after 6.0 cal ka BP), the intensity of regional background fires and number of local fires decreased.
Starting from the respective onomastic landscapes of Dionysos and Poseidon, this chapter draws portraits of each god before comparing them. Indeed, as far as divine onomastics, and especially cult epithets, are concerned, points of convergence can be investigated, such as fishing or plant-growing. On the other hand, oppositions are even more representative of the situation of each god in structuring axes of ancient Greek Weltanschauung: Poseidon seems to be very ‘male’ while Dionysos is definitely more mobile between genders; and while the former is deeply rooted in stability and ‘holding together’, the latter makes waves and ‘loosens’. As other deities in a polytheistic system, what distinguishes these two gods is not so much a space (the sea, for example or a domain (such as that of vegetation) as the way in which they invest it. In other words, gods and goddesses of ancient polytheisms can be better understood when looking at their relations with and situations vis-à-vis each other.
Edited by
Alik Ismail-Zadeh, Karlsruhe Institute of Technology, Germany,Fabio Castelli, Università degli Studi, Florence,Dylan Jones, University of Toronto,Sabrina Sanchez, Max Planck Institute for Solar System Research, Germany
Abstract: Hydrological sciences cover a wide variety of water-driven processes at the Earth’s surface, above, and below it. Data assimilation techniques in hydrology have developed over the years along many quite independent paths, following not only different data availabilities but also a plethora of problem-specific model structures. Most hydrologic problems that are addressed through data assimilation, however, share some distinct peculiarities: scarce or indirect observation of most important state variables (soil moisture, river discharge, groundwater level, to name a few), incomplete or conceptual modelling, extreme spatial heterogeneity, and uncertainty of controlling physical parameters. On the other side, adoption of simplified and scale-specific models allows for substantial problem reduction that partially compensates these difficulties, opening the path to the assimilation of very indirect observations (e.g. from satellite remote sensing) and efficient model inversion for parameter estimation. This chapter illustrates the peculiarities of data assimilation for state estimation and model inversion in hydrology, with reference to a number of representative applications. Sequential ensemble filters and variational methods are recognised to be the most common choices in hydrologic data assimilation, and the motivations for these choices are also discussed, with several examples.
Examining the ecological consequences of the late Quaternary megafaunal extinctions within biodiversity hotspots is crucial for our understanding of the potential consequences of contemporary extinctions. We present the first multi-species record of spores of coprophilous fungi (SCF) from Monquentiva and the high-Andean forests of Colombia to reconstruct Late Pleistocene and Holocene megafaunal abundance. Fossilised pollen and charcoal are used to examine the consequences of megafaunal declines on the surrounding vegetation and fire activity. Our SCF record indicates the presence of Pleistocene megafauna at least since 30,290 BP, with two waves of megafaunal decline at ca. 22,900 BP and 10,990 BP. At Monquentiva, megafaunal decline in the Early Holocene resulted in transitional non-analogue vegetation, loss of some herbivore-dispersed plant taxa, an encroachment of palatable and woody flora, and a rise in fire activity. Differences with other published South-American records suggest that ecological consequences of megafaunal declines were habitat-specific. Overall, we show that ecosystems in the eastern Colombian Cordillera were highly sensitive to the decline of megafaunal populations. Under the current biodiversity crisis, management and conservation efforts must account for the effects of local herbivore declines on plant dispersal, on fire activity, and the potential loss of ecosystem services.
Whether cattle grazing in nature reserves in temperate summers ought to be provided with artificial shelter (man-made), in addition to natural shelter (vegetation), is a topic of debate. We have investigated the effect of heat-load on the use of natural versus artificial shelter (with a roof and three walls) by cattle in eight nature reserves in Belgium. GPS collars were used to monitor use of open area, natural and artificial shelter during one or two summers (per 30 min). Cattle location data were coupled to same-time values of climatic ‘heat-stress indices’ calculated from local weather stations’ measurements of air temperature, air humidity, solar radiation and wind speed. Use of open area decreased as heat-load increased. The strength of the effect, and whether the cattle sought natural or artificial shelter, were associated with the amount and spatial distribution of natural shelter in the reserve. When natural shelter was sparse, a more scattered distribution tempered the increased use of shelter with increasing heat-load. If sufficiently available, cattle preferred natural to artificial shelter. When little natural shelter was available, cattle did use the artificial shelter and especially so with increasing heat-load. Microclimatic measurements indicated that solar radiation was blocked by vegetation at least as well as by artificial shelter, and allowed more evaporative cooling. In conclusion, we found no evidence for the added value of additional artificial shelter to protect cattle from heat-load in temperate nature reserves, as long as adequate natural shelter is available.
Infective endocarditis is a rare complication of atrial septal defect closure using transcatheter procedure. We report about infective endocarditis in an 8-year-old boy 3 months after transcatheter closure using a Figulla Flex II atrial septal defect occluder. Transesophageal echocardiography showed vegetation attached to the left atrium side of the device. Device removal and atrial septal defect closure were performed. The device was less endothelialized on the left than on the right atrium side. Therefore, insufficient endothelialization may cause infective endocarditis.
This chapter describes the interactions between three-dimensional fuel metrics, intrinsic fuel properties, plant functional traits, and physical characteristics of fuels that inform a new understanding of fire and vegetation feedbacks. The integration of these themes introduces a new synthetic model of fire–vegetation feedbacks. Interrelated concepts of fire, fluid flow, functional traits, and computational fluid dynamics fire behavior models are discussed within the synthetic model framework.
Evaluating synchronies between climate and cultural changes is a prerequisite for addressing the possible effect of environmental changes on human populations. Searching for synchronies during the Middle-Upper Paleolithic transition (ca. 48–36 ka) is hampered by the limits of radiocarbon dating techniques and the large chronological uncertainties affecting the archaeological and paleoclimatic records, as well by their low temporal resolution. Here, we present a high-resolution, pollen-based vegetation record from the Bay of Biscay, sea surface temperature changes, additional 14C ages, and a new IRSL date on the fine-sediment fraction of Heinrich Stadial (HS) 6. The IRSL measurements give an age of ca. 54.0 ± 3.4 ka. The paleoclimatic results reveal a succession of rapid climatic changes during the Middle-Upper Paleolithic transition in SW France (i.e. D-O 12–8 and two distinct climatic phases during HS 4). Comparison of the new paleoclimatic record with chronologically well-constrained regional archaeological changes shows that no synchronies exist between cultural transitions and environmental changes. The disappearance of Neanderthals and the arrival of Homo sapiens in SW France encompassed a long-term forest opening, suggesting that Homo sapiens may have progressively replaced Neanderthals from D-O 10 to HS 4 through competition for the same ecological niches.
Green roof technology can partially mitigate the adverse effects of urbanization by controlling stormwater runoff, pre-filtering water, minimizing climate change outcomes and reducing heat island effects. However, improvements to current green roof systems and innovative approaches are paramount to advancing environmental benefits and consumer acceptance of this technology. Regular green roofs are hindered by high cost and mass, as well as the incorporation of large amounts of polymers. Hydroponic green roofs (HGRs) require specific setups, maintenance and frequent replacement of plant-growing substrate, with limited energy savings in the heating and cooling load of the building due to the space between the roof surface and the hydroponic setup. In this review, a comparison of regular and HGRs is provided, and research into the environmental benefits of these technologies, including stormwater control, water purification and lifecycle assessment, is summarized. Following this, the prospect of porous concrete (PC), as a combined plant-growth substrate and structural layer in a novel extensive hydroponic green roof (EHGR) design is proposed, through a compilation and analysis of recent studies reporting the feasibility of this construction material for different applications. The mechanical, hydrological and vegetative properties of PC are discussed. Finally, a new green roof system that incorporates both PC and hydroponics, termed the EHGR system, is presented. This new green roof system may help offset the effects of urbanization by providing stormwater and pollution control, runoff delay and physical and thermal benefits, while concurrently producing biomass from a reusable substrate.
Despite the critical role of plants in enabling all life on Earth, many people fail to recognize the importance of vegetal life ("plant blindness"). Further, most modern Eurowestern knowledges of plants tend to instrumentalize them, focusing on how plants are useful rather than on how they live their lives. The field of Critical Plant Studies (CPS) has recently emerged in the Humanities to challenge this situation; this chapter explores some of the central preoccupations of this body of work. Broadly speaking, CPS considers the histories and power dynamics involved in Eurowestern utilitarian relations with the vegetal world. In addition, borrowing from insights in the Natural Sciences and also from much older forms of plant knowledge, it considers plants as living organisms with their own forms of agency, being, and desire. These two threads are woven throughout the chapter, with the aim to demonstrate that plants are sophisticated and influential agents caught up in historical and ongoing forms of biopolitics, and that overcoming plant blindness means noticing not only what the plants are doing for us, but also how we are implicated in their unfolding lifeworlds.
Salt marshes are common globally in low-lying coastal environments. Their geological settings and ecosystems vary widely by latitude and climatic settings (Chapman, 1960). Allen (2000) provides a comprehensive sketch of European salt marshes, while Rogers and Woodroffe (2014) give a recent summary of the subject. Woodwell et al. (1973) suggest that there are more than 38 million hectares (380,000 km2) of salt marshes worldwide, but specific delineation of distributions is incomplete, particularly in Asia, Africa, and South America. That area is greater than the total area of coastal American states from New Jersey to South Carolina. This chapter concentrates on the east coast of North America as containing examples of well-studied environments, with a few additional examples.
Sixty-five years ago, Teal’s (1962) study showed that salt marsh primary production was greater than community respiration. To explain this result, he suggested that marshes exported excess organic matter either directly as organic matter, or as organisms, to coastal waters. This concept, that marshes were “outwelling” material to the adjacent estuary and coastal oceans, was soon expanded to nutrients as well. However, the actual importance of the marsh in supplying organic matter and nutrients to adjacent coastal systems has been controversial and reviews debating the importance of outwelling from marshes have regularly appeared over the decades (Nixon 1980, Childers et al. 2000, Odum 2000, Valiela et al. 2000, Boynton and Nixon 2013). It has also been argued that in some cases the coastal ocean can act as a source of nutrients to the marsh and estuary (“inwelling”).
Fossil charcoals from archaeological sites provide direct evidence for the relationship between environmental change and ancient peoples’ livelihoods in the past. Our identification of 5811 fossil charcoal fragments from 84 samples suggested temperate deciduous and mixed conifer-broadleaved forests as the dominant vegetation at the Erdaojingzi site in northeastern China ca. 3500 cal yr BP; the major representative taxa were Quercus, Pinus, and Ulmus. Four woody plants probably supplied humans with food resources at the Erdaojingzi site, including Quercus, Ulmus, Amygdalus/Armeniaca, and Ziziphus. The nuts of Quercus were utilized as staple foods because of their rich starch content. The leaves of Ulmus may have been used by humans because of their massive dietary fibre. Amygdalus/Armeniaca and Ziziphus probably provided fruits for humans. Based on the coexistence approach (CA) used on the fossil charcoals, we found that the MAT anomaly was 7.9 ± 5.9°C at ca. 3500 cal yr BP, which is almost the same as the modern one (7.8°C), while the MAP was halved from 772 ± 301 mm at ca. 3500 cal yr BP to 370 mm currently. The wet climate might have facilitated significant development of rain-fed agriculture, promoted the emergence of large settlements, and eventually facilitated the birth of civilization.
Reconstructions of prehistoric vegetation composition help establish natural baselines, variability, and trajectories of forest dynamics before and during the emergence of intensive anthropogenic land use. Pollen–vegetation models (PVMs) enable such reconstructions from fossil pollen assemblages using process-based representations of taxon-specific pollen production and dispersal. However, several PVMs and variants now exist, and the sensitivity of vegetation inferences to PVM selection, variant, and calibration domain is poorly understood. Here, we compare the reconstructions, parameter estimates, and structure of a Bayesian hierarchical PVM, STEPPS, both to observations and to REVEALS, a widely used PVM, for the pre–Euro-American settlement-era vegetation in the northeastern United States (NEUS). We also compare NEUS-based STEPPS parameter estimates to those for the upper midwestern United States (UMW). Both PVMs predict the observed macroscale patterns of vegetation composition in the NEUS; however, reconstructions of minor taxa are less accurate and predictions for some taxa differ between PVMs. These differences can be attributed to intermodel differences in structure and parameter estimates. Estimates of pollen productivity from STEPPS broadly agree with estimates produced for use in REVEALS, while comparison between pollen dispersal parameter estimates shows no significant relationship. STEPPS parameter estimates are similar between the UMW and NEUS, suggesting that STEPPS parameter estimates are transferable between floristically similar regions and scales.
To investigate the response of the fish community structure to a natural disturbance in their habitat, fish abundance, biomass and species composition were analysed in relation to temporal variability of environmental conditions in a seagrass Zostera marina bed. A total of 3024 fishes belonging to 46 taxa (22 families) were collected by quantitative sampling for 10 years from 2007 to 2016 in the Seto Inland Sea, south-western Japan. Seagrass shoot density decreased to less than 1/20 of its original density after disappearance of vegetation caused by heavy rain in the autumn of 2011 and the area did not recover for the next five years. In order to analyse temporal changes of fish community, the fishes were divided into three groups depending on their habitats or lifestyles: pelagic or migratory species (PM), sand or mud bottom-associated species (SM) and seagrass (Z. marina) – or substrate (rocky bottom including macrophytes) – associated species (ZS). Multiple regression analysis showed seagrass shoot density had the most significant effect on biomass of ZS among the three groups, with higher fish biomass under higher seagrass shoot density. Fish community composition changed after the disappearance of the seagrass vegetation coverage with an increase in abundance of SM during the five years of the post-disturbance period. Seagrass vegetation was concluded to affect temporal change of fish community structure through a stronger influence on fish species that are more dependent on seagrass beds as habitat.
Infective endocarditis is a microbial infection of the endothelial surface of the heart, predominantly the heart valves, that is associated with high mortality and morbidity. Few contemporary data exist regarding affected children in our context.
Aims and Objectives:
We aimed to describe the profile and treatment outcomes of infant and childhood endocarditis at our facilities.
Methods:
This is a retrospective analysis of infants and children with endocarditis at two public sector hospitals in the Western Cape Province of South Africa over a 5-year period. Patients with “definite” and “possible” endocarditis according to Modified Duke Criteria were included in the review.
Results:
Forty-nine patients were identified for inclusion; 29 had congenital heart disease as a predisposing condition; 64% of patients met “definite” and 36% “possible” criteria. The in-hospital mortality rate was 20%; 53% of patients underwent surgery with a post-operative mortality rate of 7.7%. The median interval from diagnosis to surgery was 20 days (interquartile range, 9–47 days). Valve replacement occurred in 28% and valve repair in 58%. There was a significant reduction in valvular dysfunction in patients undergoing surgery and only a marginal improvement in patients treated medically. Overall, 43% of patients had some degree of residual valvular dysfunction.
Conclusion:
Endocarditis is a serious disease with a high in-hospital mortality and presents challenges in making an accurate diagnosis. Despite a significant reduction in valvular dysfunction, a portion of patients had residual valvular dysfunction. Early surgery is associated with a lower mortality rate, but a higher rate of valve replacement compared with delayed surgery.
Deciduous tree leaf and grass samples were collected in Debrecen, the second largest city in Hungary. The aim of the study was to determine the rate of fossil fuel-derived carbon in urban vegetation. At the locations sampled, C3 and C4 plants close to roads were collected in September 2017. In total, 82 tree and grass leaf samples were gathered at 36 different sampling points all over the city of Debrecen. The radiocarbon (14C) results of the samples were compared to the local urban background atmospheric 14CO2 data to determine the percentage of the fossil fuel-derived carbon in the plants. Based on our results, the average fossil carbon content in the tree and grass leaf samples were 0.9 ± 1.2% and 2.5 ± 2.5%, respectively. The highest fossil carbon content was 9.6 ± 0.6% in a grass and 4.7 ± 0.7% in a tree leaf sample. It appears that the negative fossil carbon content results obtained at urban sampling areas reflect modern carbon emission, where radiocarbon content is higher than the corresponding local background, presumably due burning of recent wood containing bomb 14C in the suburbs as well as other possible sources such as litter decomposition or soil CO2 emission.
We present a multiproxy record using pollen, magnetic susceptibility, carbon isotopic composition, carbon/nitrogen ratio, and particle size of mid- to late Holocene environmental changes based on a sediment core from the Pomaeho lagoon on the east coast of Korea. The records indicate that climate deteriorations around 6400 cal yr BP and 4000 cal yr BP caused rapid vegetation changes in the study area, which were presumably attributable to low sunspot activity and strong El Niño–like conditions, respectively. These two cooling events were likely modulated by different climate mechanisms, as El Niño–Southern Oscillation activity began to strengthen around 5000 cal yr BP. These events may have had a substantial impact on ancient societies in the study area. Combining our results with archaeological findings indicated that climate deterioration led to drastic declines in local populations around 6400 cal yr BP, 4400 cal yr BP, and 4000 cal yr BP. Because of its high population, coastal East Asia (e.g., eastern China, Japan, and Korea) is particularly vulnerable to potential cooling events in the future. Therefore, there is a strong need for detailed paleoclimate information in this region.
Palaeoecology has been prominent in studies of environmental change during the Holocene epoch in Scotland. These studies have been dominated by palynology (pollen, spore and related bio-and litho-stratigraphic analyses) as a key approach to multi- and inter-disciplinary investigations of topics such as vegetation, climate and landscape change. This paper highlights some key dimensions of the pollen- and vegetation-based archive, with a focus upon woodland dynamics, blanket peat, human impacts, biodiversity and conservation. Following a brief discussion of chronological, climatic, faunal and landscape contexts, the migration, survival and nature of the woodland cover through time is assessed, emphasising its time-transgressiveness and altitudinal variation. While agriculture led to the demise of woodland in lowland areas of the south and east, the spread of blanket peat was especially a phenomenon of the north and west, including the Western and Northern Isles. Almost a quarter of Scotland is covered by blanket peat and the cause(s) of its spread continue(s) to evoke recourse to climatic, topographic, pedogenic, hydrological, biotic or anthropogenic influences, while we remain insufficiently knowledgeable about the timing of the formation processes. Humans have been implicated in vegetational change throughout the Holocene, with prehistoric woodland removal, woodland management, agricultural impacts arising from arable and pastoral activities, potential heathland development and afforestation. The viability of many current vegetation communities remains a concern, in that Scottish data show reductions in plant diversity over the last 400 years, which recent conservation efforts have yet to reverse. Palaeoecological evidence can be used to test whether conservation baselines and restoration targets are appropriate to longer-term ecosystem variability and can help identify when modern conditions have no past analogues.
Gemella is a genus of Gram-positive bacteria found in the digestive tract of humans. They rarely cause systemic illness but have been recently implicated in several serious infections. We report infective endocarditis caused by Gemella bergeri in a 23-year-old with a bicuspid aortic valve status post-intervention in infancy.