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51.
52.
More sustainable dietary patterns are needed to mitigate global warming. This study aims to identify data-driven healthy dietary patterns that benefit the environment. In EPIC-NL, diet was assessed using a 178-item FFQ in 36,203 participants aged 20–70 years between 1993 and 1997. The Dutch Healthy Diet index 2015 (DHD15-index) was used to score healthiness of the diet. As proxy for environmental impact, greenhouse gas (GHG) emissions were calculated using life cycle analysis. To determine patterns that are both healthy and environmentally friendly, reduced rank regression was applied. A “Plant-based Pattern” characterized by high consumption of fruits, vegetables, and legumes, and low consumption of fries, red meat, and processed meat and a “Dairy-based Pattern” characterized by high consumption of dairy, and nuts and seeds and low consumption of coffee and tea, sugar-containing sodas, low-fiber bread, and savory sauces were derived. At equal energy intake, the diet of adherents (highest quartile) to the “Plant-based Pattern” were significantly healthier (89.8 points on the DHD15-index, p?<?0.0001) and more sustainable (3.96 kg C02-eq/day, p?<?0.0001) compared to the average diet (76.2 points, 4.06 kg C02-eq/day), whereas the “Dairy-based Pattern” was somewhat healthier (77.9 points, p?<?0.0001), but less sustainable (4.43 kg C02-eq/day, p?<?0.0001). When deriving dietary patterns based on health and environmental aspects of the diets, a “Plant-based” and a “Dairy-based” pattern were observed in our study population. Of these, the plant-based diet benefits health as well as the environment.  相似文献   
53.
The classical explanation of the development of the Welsh landscape by the effects of a pulsed ‘eustatic’ uplift during the Cenozoic times is challenged by new data on the geology and geomorphology of Wales and the adjacent regions. The post-Caledonian surface developed over most of Wales in the upper Westphalian plays a major role in landform development. Since its emergence before mid-Cretaceous times, the Welsh Massif has suffered a long subaerial evolution which favoured a powerful chemical weathering. In Anglesey and St. David's Land, residual hills were formed by a process of differential weathering, and downwearing in saprolites. The Millstone Grit quartzites have been deeply weathered and dolines or flat-bottomed basins have been developed. From Cretaceous to Miocene times, a morphotectonic equilibrium has existed between uplift and denudation, so that, in the major part of Wales, the original planation surface was constantly maintained by lowering on itself and in some places it is possible to prove that no more than a few dozen metres of rock thickness disappeared during that period. Several main escarpments were produced by the warping of the planation surface along sharp flexures, during Neogene times. The Cenozoic vertical movements were controlled by the Caledonian or pre-Caledonian tectonic pattern which has divided the continental crust into major structural units. Welsh tectonic development is related to the opening of the North Atlantic, associated stresses reactivating ancient lines of weakness in the heterogeneous lower crust or upper mantle.  相似文献   
54.
Yvonne P Elsworth and Michael J Thompson examine the theory and practice of asteroseismology, the study of the oscillations of Sun-like stars.  相似文献   
55.
The southern continental margin of Australia is a cool-water carbonate sedimentary province located in a high-energy, swell-dominated oceanographic setting. A vibrocore transect of 14C-dated sediments across the centre of the Eucla Shelf is the first record of Holocene shelf deposition in the Great Australian Bight. Much of the seafloor shallower than 70 m water depth, the base of wave abrasion, is bare Cenozoic limestone, in some places encrusted by (?) Late Pleistocene, coral-rich, limestone that is cemented by high-magnesium calcite (12 mole% MgCO3). The areally extensive, 100 km-wide, hard, bored substrate supports an epibiota of coralline algae, minor bryozoans and soft algae or is covered by patches of Holocene sediment up to 1.5 m thick; generally a basal bivalve lag (< 3 ka) overlain by quartzose-bioclastic palimpsest sand. This pattern of active carbonate production but little accretion on the wave-swept mid- to inner-shelf is similar to that on other parts of the southern Australian continental margin. The term shaved shelf is proposed for this style of carbonate platform, formed by alternating periods of sediment accretion, cementation and erosion.

The palimpsest sand is typically rich in bivalves, coralline algae and locally, detrital dolomite. Outer shelf Holocene sediment, below the base of wave abrasion but inboard of the shelf edge, is a metre-thick unit of fine, microbioclastic muddy sand with minor delicate bryozoans overlying a 9–13 ka rhodolith gravel. Some of this outer shelf sediment appears to have been resedimented. The shelf edge is a sandy and rocky seafloor with active bryozoan growth and sediment production.

The Holocene sediments are enriched in coralline algal particles and conspicuous large foraminifers (cf. Marginopora) and depleted in bryozoans, as compared to coeval deposits on the Lacepede and Otway shelves off southeastern Australia. These differences are interpreted to reflect warmer waters of the Leeuwin Current and prevalent downwelling in this area as opposed to the general upwelling and colder waters in the east.  相似文献   

56.
Submarine lobes have been identified within various deep-water settings, including the basin-floor, the base of slope and the continental slope. Their dimensions and geometries are postulated to be controlled by the topographic configuration of the seabed, sediment supply system and slope gradient. Ten experiments were conducted in a three-dimensional-flume to study the depositional characteristics of submarine lobes associated with: (i) different basin floor gradients (0 to 4°); (ii) different sediment concentrations of the parent turbidity current (11 to 19% vol); and (iii) varying discharge (25 to 40 m3 h−1). Most runs produced lobate deposits that onlapped onto the lower slope. Deposit length was proportional to basin-floor angle and sediment volume concentration. A higher amount of bypass is observed in the proximal area as the basin-floor angles get steeper and sediment concentrations higher. Deposits of runs with lower discharge could be traced higher upslope while runs with higher discharge produced an area of low deposition behind the channel mouth, i.e. discharge controlled whether lobe deposits were attached or detached from their channel-levée systems. A particle-advection-length scale analysis suggests that this approach can be used as a first order estimation of lobe element length. However, the estimations strongly depend on the average grain size used for calculations (for example, silt is still actively transported after all sand has been deposited) and the method cannot be used to locate the main depocentre. Furthermore, attempted reconstructions of turbidity current velocities from natural systems suggest that the method is not appropriate for use in inversions from more complex composite bodies such as lobes.  相似文献   
57.
Sedimentary facies in the distal parts of deep‐marine lobes can diverge significantly from those predicted by classical turbidite models, and sedimentological processes in these environments are poorly understood. This gap may be bridged using outcrop studies and theoretical models. In the Skoorsteenberg Formation (South Africa), a downstream transition from thickly bedded turbidite sandstones to argillaceous, internally layered hybrid beds, is observed. The hybrid beds have a characteristic stratigraphic and spatial distribution, being associated with bed successions which generally coarsen and thicken‐upward reflecting deposition on the fringes of lobes in a dominantly progradational system. Using a detailed characterization of bed types, including grain size, grain‐fabric and mineralogical analyses, a process‐model for flow evolution is developed. This is explored using a numerical suspension capacity model for radially spreading and decelerating turbidity currents. The new model shows how decelerating sediment suspensions can reach a critical suspension capacity threshold beyond which grains are not supported by fluid turbulence. Sand and silt particles, settling together with flocculated clay, may form low yield strength cohesive flows; development of these higher concentration lower boundary layer flows inhibits transfer of turbulent kinetic energy into the upper parts of the flow ultimately resulting in catastrophic loss of turbulence and collapse of the upper part of the flow. Advection distances of the now transitional to laminar flow are relatively long (several kilometres) suggesting relatively slow dewatering (several hours) of the low yield strength flows. The catastrophic loss of turbulence accounts for the presence of such beds in other fine‐grained systems without invoking external controls or large‐scale flow partitioning and also explains the abrupt pinch‐out of all divisions of these sandstones. Estimation of the point of flow transformation is a useful tool in the prediction of heterogeneity distribution in subsurface systems.  相似文献   
58.
The Pliocene Norwest Bend Formation is a well‐preserved succession of terrestrial and shallow‐marine deposits in the Murray Basin, South Australia. Sediments in this unit consist of two discrete terrigenous clastic‐rich, decametre‐scale sequences, or informal members, which record episodes of marine incursion during the Early and Late Pliocene respectively. The base of each sequence is a transgressive lag and/or strandline deposit that is transitional upwards into a highstand, subtidal, terrigenous clastic and cool‐water carbonate sediment accumulation. The top of each sequence is incised by fluvial channels that are filled by river deposits which formed as relative sea‐level fell and terrestrial environments prograded basinward. Sedimentological data suggest that gross stratigraphic architecture was primarily determined by glacioeustasy. Differences in sedimentary style between these two sequences, however, reflect a major climatic change that took place in southern Australia during the mid‐Pliocene. The lower quartzose sand member is formed of siliciclastic sediment derived from prolonged, deep, subaerial weathering and contains a bivalve‐dominated, cool‐temperate, open‐marine mollusc assemblage. These sediments accumulated under an equitable, relatively warm, humid climate. The Murray Basin during this time, because of high fluvial discharge, was a salt‐wedge estuary with typical estuarine circulation. In contrast, the upper, oyster‐rich member is typified by large monospecific oyster buildups that grew in restricted coastal environments. Strandline deposits contain a warm‐temperate skeletal assemblage. Contemporaneous aeolian sediments accumulated under warm, semi‐arid climatic conditions. Well‐developed ferricrete, silcrete and calcrete horizons reflect cyclic conditions of rainwater infiltration and evaporation in the seasonally dry climate that typifies southern Australia today. Highly seasonal rainfall produced an estuary that fluctuated annually from being well to partially mixed. These Pliocene sediments support the notion that mollusc‐rich facies are the signature of cool‐water carbonate accumulations in inboard neritic environments. Unlike bryozoans that dominate the outer parts of Cenozoic cool‐water carbonate shelves, molluscs evolved to exploit an array of coastal ecosystems with wide salinity variations and variable sedimentation rates.  相似文献   
59.
In order to distinguish the buffering capacity associated with functional groups in the cell wall from that resulting from metabolic processes, the base or acid consumption of live and dead cells of the Gram-negative bacterium Shewanella putrefaciens was measured as a function of time in a pH stat system. Under neutral (pH 7) to basic (pH 8 and 10) conditions, base neutralization by suspensions of live bacteria beyond 1 h was clearly due to respiratory activity. At pH 4, however, proton neutralization ceased after 50 min due to cell death. Dead cells only produced or consumed protons during the very first minutes after exposure to pH 4, 8 or 10. From the time-dependent acid and base consumption curves of live cells, and the comparison of the acid–base activity of live and dead cells, the charging of ionizable groups in the cell wall was derived. From pH 4 to 10, cell wall charge increases from 0 to about − 4 × 10− 16 mol cell− 1.  相似文献   
60.
Abstract

Multi-stakeholder sustainability certification schemes have become a favorite instrument for applying good governance, though studies indicate their inefficiency at the producer level. In this study, we used a mixed-method approach to first, map the institutional context of independent oil-palm smallholders in rural Sumatra while, second, reflecting upon the impact of the Smallholder Standard proposed by the Roundtable on Sustainable Palm Oil on smallholder management practices. We hold that non-recognition of micro-scale perspectives within governance processes may partially explain noncompliance with certification principles among smallholders. The Smallholder Standard appears unable to mitigate challenges important for smallholders, who in turn cannot properly comply with it, due to problems including weather instability and high management costs. We suggest that certification schemes need to work on some overlooked but essential preconditions of good governance, namely gaining micro-level visibility and acceptance.  相似文献   
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