Evolution Of Islands Research Articles

NTM threshold island width measurements on Globus-M based on the Fitzpatrick heat transport model

We estimate the neoclassical tearing mode (NTM) threshold island width, Wc, associated with the bootstrap current contribution to the time evolution of the magnetic island. Following the original work by Fitzpatrick, we solve the heat transport equation for the electron temperature distribution with Wc being the input parameter. The obtained model temperature profile is then fitted to the Globus-M Thomson scattering (TS) data to deduce the actual Wc value. Due to the relatively low resolution of the Globus-M TS in the island region, we have also adopted ASTRA to provide the benchmarking.

Coastal landscape evolution of Corsica island (W. Mediterranean): palaeoenvironments, vegetation history and human impacts since the early Neolithic period

A multi-proxy investigation of sediment cores has enabled us to reconstruct the coastal environmental evolution of East-Central Corsica (the sites of Saint Florent, Piantarella-Bonifacio and Palo-Solenzara) for the last 8000 years. The analytical methods comprise pollen (five original pollen diagrams), weight loss-on-ignition measurements, laser granulometry, and ostracod identification. In addition, 26 radiocarbon dates are used to provide a robust chronostratigraphy for the sedimentary sequences. The assessment of coastal landscape dynamics enables us to define the major morphological changes and to evaluate the complex interplay between climatic forcing and anthropogenic activity on the vegetation history of Corsica, within an archaeological context, since the early Neolithic period (∼7.4 cal kyr BP). The major findings are that the first farmers reached Corsica by sea, and they encountered a coastal environment mainly composed of freshwater ponds located close to the shoreline. This specific paleoenvironmental feature offered a favourable location for agriculture and for the development of permanent settlements where a subsistence economy was developed. Since the Middle Holocene, postglacial sea-level rise has caused major changes in local coastal environments, often characterized by salt intrusion into freshwater bodies. At the transition between the Mid and Late Holocene (∼4.0 cal kyr BP), an increase in both salinity and aridity caused substantial landscape changes, mainly characterized by a further expansion of saline marshland, mainly occupied by Chenopodiaceae. The results also provide new insights into the role of Erica in the original Holocene vegetation of Corsica. Our data clearly indicate that an Erica arborea - Quercus ilex forest transition occurred before 6.3 cal kyr BP, significantly earlier than previously proposed. Finally, the earliest evidence of cereal cultivation is at ∼7350 cal kyr BP, and in addition we are better able to constrain the role of humans in the landscape dynamics of Corsica since the early Neolithic.

Manipulating the Edge of a Two-Dimensional MgO Nanoisland

We investigate the morphology evolution and electronic properties of MgO islands grown on the Ag(001) substrate by the reactive deposition method using low-temperature scanning tunneling microscopy...

Effects of Holocene climate changes on alpine ecosystems: Nonequilibrium dynamics drive insect species richness on alpine islands

AbstractAimTo identify the effect of multiple, temporally close, forcing events (i.e. climate‐driven habitat fragmentations/homogenizations) in shaping current patterns of biodiversity in alpine areas. Given their spatial configuration, alpine areas have been traditionally seen as islands surrounded by an “ocean” of unsuitable lands. A quantitative assessment of the effects of Holocene climate fluctuations on islands area and inter‐island connectivity is crucial to finely reconstruct past biodiversity dynamics and forecast species responses to future changes.LocationItaly.TaxaCarabidae (Ground beetles), Chrysomelidae (Leaf beetles), Elateridae (Click beetles), Orthoptera (Grasshoppers and Crickets) and Papilionoidea (Butterflies and Skippers).MethodsA total of 1,077 species for 128,093 records were analysed and a classification based on their functional traits allowed identifying groups of good and poor dispersers within each taxon. A dynamic discrete model of ecosystem evolution provided the spatio‐temporal context to test two competing (transient equilibria vs. nonequilibrium) dynamics based on different colonization capabilities. In the transient equilibria dynamic the species are able to respond to island evolution through successful dispersal and colonization events, whereas in the nonequilibrium dynamic ineffective immigration constrains the current species richness to that generated by the strongest island contraction.ResultsWith the exception of Elateridae, good dispersers (Chrysomelidae and Papilionoidea) responded to environmental changes by establishing a series of transient equilibria. In contrast, the nonequilibrium dynamic better described patterns of species richness in poor dispersers (Carabidae and Orthoptera).Main conclusionsOur approach could be used as the basis for the development of spatially and temporally explicit models of island evolution and could be a valuable tool for quantifying the sensitivity of single taxa to climate‐driven habitat changes. It also represents a further step towards the forecasting of future responses to climate change and the accompanying development of conservation strategies that more effectively respond to the detrimental impacts of climate change on biodiversity.

Seamount‐Volcanic Island Transition and Evolution From Fissural to Central Activity Inferred by the Magnetic Modeling of Salina Island (Tyrrhenian Sea)

AbstractVolcanic islands represent the later stage of an early submarine volcanic activity and show different morphologies reflecting the geometry of shallow plumbing systems, magma output rate, gravitational instability, and erosive phases. Two end‐member morphologies may be recognized: (a) rift‐like elongated edifices and ‘stellate’ volcanoes and (b) cone‐shaped, central‐type volcanoes. While the evolution from early conical shapes to stellate shapes is relatively well known, the reverse is less constrained, commonly lacking geophysical and geological data to support it. We present magnetic forward and 3‐D inverse models of the volcanic island of Salina (244‐15 ka; Aeolian Arc, Southern Tyrrhenian Sea) to characterize its shallow plumbing system. The detected magnetic sources are interpreted as the crystallized portions of dykes and vertical conduits. The dykes mainly characterize the offshore of Salina Island, whereas subcircular conduits are located onshore. The results show that the early, mainly submarine phases of Salina concentrated along dykes following weakness zones of tectonic significance. As the volcanism proceeded, the subaerial activity focused on two main cone‐shaped stratovolcanoes (Monte Fossa delle Felci and Monte dei Porri). The intersections among dykes and the progressive loading of volcanic products during the early growth of Salina are responsible for the transition from an early fissural basaltic activity to a later, basaltic to a last, more evolved central‐type volcanism. We conclude that intrusions along pre‐existing tectonic structures, dyke intersections, and loading processes related to the formation of a volcanic pile regulate the morphology and structural evolution of volcanic islands from the early, submarine phase to the later subaerial activity.

Effects of plasmoid formation on sawtooth process in a tokamak

For realistic values of the Lundquist number in tokamak plasmas, 1/1 magnetic islands lead to the formation of a secondary thin current sheet, which breaks up into a chain of small magnetic islands, called plasmoids. The role of plasmoid dynamics during the sawtooth reconnection process in fusion plasmas remains an unresolved issue. In this study, systematic simulations are performed to investigate the resistive internal kink mode using the full resistive magnetohydrodynamics equations implemented in the NIMROD code in a simplified tokamak geometry. For Lundquist number S≥1.6×107, the secondary current sheet is found to be unstable to plasmoids during the nonlinear resistive kink mode evolution with a critical aspect ratio of the current sheet of ∼70. The merging of small plasmoids leads to the formation of a monster plasmoid that can significantly affect the primary island evolution. This may provide an explanation for the partial reconnection observed in sawtooth experiments.

Geomorphic response of inlet barrier islands to storms

Inlet Barrier Islands (IBIs) are infrequently studied, and are often poorly represented in coastal lidar records. The fetch limited barrier island (FLBI) model was introduced to describe geomorphic changes of IBIs over time. The FLBI model predicts that the morphology of IBIs should remain largely static during predominate weather conditions due to sheltering from oceanic wave energy but undergo significant erosion when local and non-local waves magnify during storms, subsequently failing to recover volume and elevation losses. Using three years of high-frequency small unoccupied aircraft systems (sUAS, aka drone) surveys and existing lidar records, we document geomorphic changes on Bird Shoal (a protective IBI near the town of Beaufort, NC) resulting from storms and predominate conditions, testing the FLBI model and documenting island evolution. Our results indicate that Bird Shoal exhibits different spatial trends in erosion, accretion, and shoreline migration across its 4 km length, likely driven by varying shoreline orientation to the Beaufort Inlet and back barrier bathymetry in Back Sound. Our data indicate that the geomorphic behavior of Bird Shoal currently does not adhere to the classic FLBI model. Foreshore storm recovery and growth on Western Bird Shoal and shoreline retreat on Central Bird Shoal occurred during predominate conditions, and beach morphology was not an artifact of past storm events. The Western Bird Shoal shoreline consistently retreated landward in decades of historic imagery, but transitioned to seaward expansion sometime between 2011 and 2014. This shift is likely driven by erosion of the western end of Shackleford Banks and concurrent widening of the Beaufort Inlet, allowing increased wave energy to enter the back-barrier sound and push flood deltas onto Bird Shoal during predominate conditions. Our results suggest that open ocean inlet width and location interact with back-barrier deltas to control sediment supply and wave energy for IBIs, and that IBIs may fall into and out of conformance with the FLBI archetype over time. This study demonstrates sUAS deploying frequently over a municipal scale to fill spatial and temporal gaps in traditional coastal remote sensing datasets.

Topological bifurcation of magnetic islands in NSTX-U

Topological bifurcations of magnetic islands are observed in two M3D-C1 linear resistive magnetohydrodynamic calculations of model NSTX-U equilibria during the application of small 3D magnetic perturbation fields. In comparison to a DIII-D ELM suppression case, reconstructed from shot 147170 at time slice 3745 ms, we propose that a stronger kink response in the NSTX-U plasma may be the primary cause of the bifurcations. Island evolution and bifurcations in both the DIII-D and the two NSTX-U cases with the increase of perturbation current are analyzed. Further, a hypothesis is proposed that such magnetic island topology bears an intrinsic property to confine charged particles and cause their density inside the islands to rise, which is examined by implementing a random kick algorithm in the magnetic field line integration code TRIP3D-GPU to approximate electron collisional transport. Although full consideration of all the forces between electrons is missing, as it requires 3D large scale kinetic simulation in toroidal geometry, the positive result of this approximate transport simulation does provide a first step confirmation towards fully validating the hypothesis.

Electron acceleration in interaction of magnetic islands in large temporal-spatial turbulent magnetic reconnection

A new combined Fermi, betatron, and turbulent electron acceleration mechanism is proposed in interaction of magnetic islands during turbulent magnetic reconnection evolution in explosive astrophysical phenomena at large temporal-spatial scale (LTSTMR), the ratio of observed current sheets thickness to electron characteristic length, electron Larmor radius for low-β and electron inertial length for high-β, is on the order of 1010–1011; the ratio of observed evolution time to electron gyroperiod is on the order of 107–109). The original combined acceleration model is known to be one of greatest importance in the interaction of magnetic islands; it assumes that the continuous kinetic-dynamic temporal-spatial scale evolution occurs as two separate independent processes. In this paper, we reconsider the combined acceleration mechanism by introducing a kinetic-dynamic-hydro full-coupled model instead of the original micro-kinetic or macro-dynamic model. We investigate different acceleration mechanisms in the vicinity of neutral points in magnetic islands evolution, from the stage of shrink and breakup into smaller islands (kinetic scale), to the stage of coalescence and growth into larger islands (dynamic scale), to the stages of constant and quasi-constant (contracting-expanding) islands (hydro scale). As a result, we give for the first time the acceleration efficiencies of different types of acceleration mechanisms in magnetic islands’ interactions in solar atmosphere LTSTMR activities (pico-, 10–2–105 m; nano-, 105–106 m; micro-, 106–107 m; macro-, 107–108 m; large-, 108–109 m).

The Spatio-Temporal Evolution of River Island Based on Landsat Satellite Imagery, Hydrodynamic Numerical Simulation and Observed Data

A river island is a shaped sediment accumulation body with its top above the water’s surface in crooked or branching streams. In this paper, four river islands in Yangzhong City in the lower reaches of the Yangtze River were studied. The spatio-temporal evolution information of the islands was quantitatively extracted using the threshold value method, binarization model, and cluster analysis, based on Thematic Mapper (TM) and Enhanced Thematic Mapper+ (ETM+) images of the Landsat satellite series from 1985 to 2015. The variation mechanism and influencing factors were analyzed using an unstructured-grid, Finite-Volume Coastal Ocean Model (FVCOM) hydrodynamic numerical simulation, as well as the water-sediment data measured by hydrological stations. The annual average total area of these islands was 251,224.46 m2 during 1985–2015, and the total area first increased during 1985–2000 and decreased later during 2000–2015. Generally, the total area increased during these 30 years. Taipingzhou island had the largest area and the biggest changing rate, Xishadao island had the smallest area, and Zhongxinsha island had the smallest changing rate. The river islands’ area change was influenced by river runoff, sediment discharge, and precipitation, and sediment discharge proved to be the most significant natural factor in island evolution. River island evolution was also found to be affected by both runoff and oceanic tide. The difference in flow-field caused silting up in the Leigongdao Island and the head of Taipingzhou Island, and a serious reduction in the middle and tail of Taipingzhou Island. The method used in this paper has good applicability to river islands in other rivers around the world.

Application of Statistical Models and Satellite Imagery in the Evolution of Heat Island in Hamedan City

Application of Statistical Models and Satellite Imagery in the Evolution of Heat Island in Hamedan City

Tearing Mode Behavior in the Globus-M Spherical Tokamak Plasma

The 2/1 tearing mode instability during the plateau phase of the plasma current time evolution has been observed since the start of the Globus-M spherical tokamak operation. Because of a small amount of shots in a database, the poloidal beta dependence of the instability growth rate had been investigated with an insufficient accuracy. In this work, a more detailed analysis has been produced that proves the fact that the observed modes can be treated as neoclassical. The saturated island width as a function of poloidal beta has been obtained; a time evolution of the magnetic island has been calculated from the Mirnov magnetic coil signals and compared to the modified Rutherford theory, and the critical magnetic island width has been found for the neoclassical tearing mode (NTM) of the Globus-M tokamak.

Spatial-temporal evolution of urban heat Island in Xi'an from 2006 to 2016

During the rapid development of urbanization, the urban heat island (UHI), becomes one of the major urbanization progress problems that affects the environmental, social and ecology profoundly. Analyzing the UHI can help understanding the UHI status and the physical characteristics of cities, and is significant to provide ecosystem management plans and mitigation strategies for the UHI. By utilizing the MODIS LST products, Landsat series data and the ecological regionalization data, and applying the corresponding methods to derive the NDVI, the fractional vegetation cover (Fv) and the LST normalizations results, the study conducted the spatial-temporal evolution of the UHI in Xi'an from 2006 to 2016. The main work includes analyzing the spatial evolution characters, analyzing the temporal evolution characters and exploring the relationship between LST and vegetation cover. Spatial evolution results showed that the UHI to the north of the urban land control line in 2016 became intensified and enhanced in the form of increasing the LST and the UHI zone. As for the temporal evolution, the Low Temperature Zone and Sub-low Temperature Zone had little changes and corresponded with the urban land control line, and the Medium Temperature Zone decreased on large area while the Sub-high Temperature Zone increased on large area, when compared results of 2006 with that of 2016. The relationship between LST and vegetation cover indicated that increasing vegetation cover had a certain active role for reducing LST and mitigating the UHI. The positive intervention and guidance of the government on the ecological protection can reduce the UHI, effectively.

Peralkaline Felsic Magmatism of the Atlantic Islands

The oceanic-island magmatic systems of the Atlantic Ocean exhibit significant diversity in their respective sizes, ages, and the compositional ranges of the magmas they have produced. Nevertheless, almost all of the major Atlantic islands and island groups have produced peralkaline felsic magmas, implying that similar petrogenetic regimes may be operating throughout the Atlantic Ocean, and elsewhere. The origins of peralkaline magmas are frequently linked to low-degree partial melting of enriched mantle, followed by protracted differentiation in the shallow crust. Nevertheless, additional petrogenetic processes such as magma mixing, crustal melting, and contamination have been identified at numerous peralkaline centres. The onset of peralkalinity leads to magma viscosities lower than those typical for metaluminous felsic magmas, which has profound implications for processes such as crystal settling. A literature compilation demonstrates trends which suggest that the peralkaline magmas of the Atlantic Ocean islands are generated primarily via extended (up to ~ 95 %), open system fractional crystallisation of mantle-derived mafic magmas. Crustal assimilation is likely to become more significant as the system matures and low-solidus material accumulates in the crust. Magma mixing occurs between mafic and felsic end-members, and also between variably-evolved felsic magmas, and is often recognised via hybridised intermediate magmas. The peralkaline magmas are hydrous, and are frequently zoned in composition, temperature, and/or water content. They are typically stored in shallow crustal magma reservoirs (~ 2 to 5 km), which are maintained by mafic replenishment. Low melt viscosities (1 × 101.77 to 1 × 104.77 Pa s) facilitate two-phase flow, facilitating the formation of alkali-feldspar crystal mush. This mush may then contribute melt to an overlying melt lens via filter pressing or partial melting. We utilise a three stage model to account for the establishment, development, and termination of peralkaline magmatism in the ocean island magmatic systems of the Atlantic. We suggest that the overall control on peralkaline magmatism in the Atlantic is magma flux rate, which controls the stability of upper crustal magma reservoirs. The abundance of peralkaline magmas in the Atlantic suggests that their development must be a common, but not inevitable, stage in the evolution of ocean islands.

Sharp-interface approach for simulating solid-state dewetting in two dimensions: A Cahn–Hoffman [formula omitted]-vector formulation

By using a Cahn–Hoffman ξ-vector formulation, we propose a sharp-interface approach for solving solid-state dewetting problems in two dimensions. First, based on the thermodynamic variation and smooth vector-field perturbation method, we rigorously derive a sharp-interface model with weakly anisotropic surface energies, and this model describes the interface evolution which occurs through surface diffusion flow and contact line migration. Second, a parametric finite element method in terms of the ξ-vector formulation is proposed for numerically solving the sharp-interface model. By performing numerical simulations, we examine several specific evolution processes for solid-state dewetting of thin films, e.g., the evolution of small islands, pinch-off of large islands and power-law retraction dynamics of semi-infinite step films, and these simulation results are consistent with experimental observations. Finally, we also include the strong surface energy anisotropy into the sharp-interface model and design its corresponding numerical scheme via the ξ-vector formulation.

(Re)Development of fluvial islands along the lower Mississippi River over five decades, 1965–2015

The development and evolution of islands along the lower Mississippi River were examined over a 50 year period, between 1965 and 2015. Fluvial islands were historically a fundamental component of the riparian corridor, serving as important ecological habitat for aquatic and terrestrial species. Their degradation was associated with channel engineering, leading to a pronounced single thread channel. Continued channel engineering in the latter twentieth century, however, is associated with a rapid increase in channel islands along the lower Mississippi River.The study utilizes a GIS framework to examine and analyze a range of geospatial data sets, including (i) lidar DEMs, (ii) historic aerial photos, (iii) historic and recent satellite imagery, (iv) historic topographic maps, and (vi) hydrologic data from gauging stations along the lower Mississippi River. Islands were digitized in Google Earth Pro and ArcGIS by identification of vegetation lines. Spatial data (polygons) were used to extract (clip) the LiDAR DEM data for subsequent analysis. The island data was statistically analyzed using a MANOVA and two-way t-test to examine the association of dikes with the morphologic characteristics of islands.The number of islands (>1 ha) significantly increased over the five decade study period, from 105 in 1965, 206 in 1995, to 295 in 2015. The average size of islands decreased from 101 ha (hectare) to 63 ha, because so many new (small) islands formed within the dike fields. The total area of islands (within the river channel) increased from 103 km2 in 1965, 169 km2 in 1995, to 206 km2 in 2015. The total sediment storage within fluvial islands above the average low water surface is 1.81 billion m3.The lower Mississippi has sufficient coarse sediment to construct new riparian lands, despite the large historic decline in sediment load and overall channel bed degradation that occurred in response to large-scale engineering projects over much of the twentieth century. The new rapid growth and development of fluvial lands within the riparian corridor of the lower Mississippi is a positive outcome of an unintended geomorphic consequence, but one that requires additional management considerations.

Estimation of magnetic island width by the fluctuations of electron cyclotron emission radiometer on J-TEXT

The width of a magnetic island is an important parameter for the quantitative analysis of magnetohydrodynamic-related physics. An electron cyclotron emission radiometer (ECE) is a powerful tool that can be used to obtain this width, which can usually be determined from the flat temperature distribution at the O-point phase or the maxima temperature perturbation. An improved method to estimate the width of a magnetic island is proposed in this paper, and it is independent of calibration. With this method and the existing 24-channel ECE system, the width of a rotation magnetic island can be estimated. Additionally, by filtering the fluctuation ECE signal, the evolution of the magnetic island can be obtained. The results of this method are consistent with those of the integrated magnetic probe signals, which represent the relative change of the magnetic island.

Drift kinetic response of ions to magnetic island perturbation and effects on NTM threshold

Controlling neoclassical tearing modes (NTMs) is vital for future tokamaks, such as ITER. An NTM control system relies on the magnetic island threshold physics. In this paper, new results for the ion response to the island perturbation and its influence on the island evolution are presented. Considering a small island, w ≪ r, where r is the minor radius, but crucially retaining the ordering ρbi ∼ w (relevant for threshold) to capture the finite orbit width effect, we determine the ion response using the drift kinetic equation. Momentum conservation and quasineutrality are taken into account, which are crucial for determining the current perturbations. The results show that the finite particle orbit effects are significant even for a moderately small ratio of ρθi/w (ρθi is the ion poloidal Larmor radius; ρbi ∼ ϵ1/2ρθi). When w ∼ ρθi, the flattening of the pressure gradient across the island is substantially restored, implying that the bootstrap current drive for the island growth is suppressed. Moreover, we find that for a sufficiently small island, w ≪ ρθi, the contribution can be negative, meaning that it can stabilize small seed islands, providing a threshold. This will have significant impact on our understanding of the NTM threshold physics.

Influences of Domestication and Island Evolution on Dental Growth in Sheep

Domestication and island evolution can lead to changes of life history along the slow-fast gradient. Shifts of life history patterns, in turn, are potentially related to alterations of patterns and timing of tooth eruption. Schultz’s rule predicts an earlier eruption of molars relative to premolars as fecundity increases during the domestication process. On the other hand, evolution on a predator-free, resource limited island might lead to a generally slow life history and delayed tooth eruption, as in the Plio-Pleistocene Balearic caprine Myotragus. In this study, we investigate tooth eruption and its relation to life history in a unique sheep population that is an example of both domestication and island evolution: the ancient and feral Soay sheep (Ovis aries) of the St. Kilda archipelago, Scotland. Tooth eruption timing and sequence is investigated in a comparative framework featuring new data on other domestic sheep (O. aries), including European mouflon (O. a. musimon), as well as wild sheep (O. vignei, O. cycloceros, O. arkal, O. orientalis, O. ammon). These data indicate that the order of eruption is similar in wild and domestic sheep, despite the fundamental life history changes that came about with domestication. However, in contrast to other domestic sheep breeds, Soay sheep erupt their teeth at an absolute older age and also tend to grow more slowly, which resembles the evolutionary trend in island-adapted Myotragus. Despite these similarities, Soay sheep do not share the slow life history pattern inferred for Myotragus, highlighting the distinctive nature of tooth eruption in Soay sheep.

Understanding processes of island development on an island braided river over timescales from days to decades

AbstractBar colonization by vegetation and subsequent island formation is a key bio‐geomorphological process in fluvial landscape evolution. Here we investigate morphological and ecological evolution of river islands over timescales from single floods to decades, focusing on islands initiated by deposited trees that sprout to form vegetated patches.On a braided reach of the high‐energy Tagliamento River, Italy, we monitored 30 pioneer islands of 1 to 17 years age in comparison with unvegetated bar surfaces, open areas between islands, and established island surfaces. We integrated morphological, surface sediment and vegetation properties of islands initiated by different flood events, combining evidence from remotely‐sensed and ground observations, flow and climate time series.At a decadal timescale, pioneer islands aggrade rapidly to the elevation of the mean annual flood, showing a steady increase in vegetation canopy height, fining of surface sediments from predominantly gravel to silty‐sand with a notable clay and organic fraction. The standing vegetation included over 130 species, with the largest number on island surfaces of intermediate elevation and flood disturbance. As islands age, standing vegetation becomes comprised mainly of competitor species with transient seed banks and typical of woodland, scrub, pasture and wetland habitats, whereas the winter seedbank is dominated on all surfaces by ruderal species with persistent seedbanks, mainly associated with aquatic, wetland, pasture, arable and wasteland habitats. At shorter timescales, the biogeomorphological trajectory of pioneer islands is initiated by large flood events that control the elevation of deposited trees, and subsequent flows that control tree survival and establishment. Island morphological evolution depends on the frequency‐magnitude of sediment and seed delivery and redistribution by flood and possibly wind events, whereas island ability to retain sediments reflects the degree of vegetation establishment, which in the short‐term may vary with seasonal to annual moisture supply, substrate characteristics and climatic growth conditions. © 2018 John Wiley & Sons, Ltd.