bluuebunny/crossref_metadata_2025_split huggingface dataset:
Key variables controlling the vegetation of a cool‐temperate mire in northern Japan
Authors: Yabe Kazuo , Onimaru Kazuyuki 
Published: May 2006

Abstract. In the cool‐temperate Bibi Mire, Hokkaido, Japan, valley fens and flood‐plain fens have quite different vegetation. The main variables controlling the vegetation were all hydrological: mean water level, water level fluctuation and surface water flow. Chemical factors such as electrical conductivity, dissolved oxygen and related peat decomposition were less important. The pH was about neutral and has little effect. The flood‐plain fen developed under fluctuating water table conditions. The dominant species are Calamagrostis langsdotffii and Carex pseudocuraica. When temporal inundation occurs in the rainy or typhoon seasons, the submergence stimulates bud germination of the stoloniferous C. pseudocuraica, which can rapidly elongate its stolons upward. Some large floating peat mats occurred in the flood‐plain fen zone. On these mats some Alnus japonica saplings establish and patches of alder forest can arise. Here the water level was higher than in the peripheral alder forest zone.The valley fen is dominated by Carex lasiocarpa var. occultans and/or C. limosa. It is formed under stable water table conditions in the inundated parts of the mire ‐where the non‐inundated wet areas are dominated by alder trees. In the area where the surface water is flowing, these two fen sedges grow in deeper water since the high oxygen content is considered to compensate the flooding stress.
Effects of small‐scale animal disturbances on plant assemblages of set‐aside land in Central Germany
Authors: Milton S.J. , Dean W.R.J. , Klotz S. 
Published: May 2006

Abstract.The distribution, density and cover of small‐scale natural disturbances was surveyed in semi‐natural and set‐aside vegetation in a hilly landscape in Central Germany in the spring of 1995. More of the landscape was disturbed on set‐aside agricultural land in valley s (1.02 %) and on warm south‐facing slopes(1.33 %) than on rocky hilltops (0.3 %) and cool north‐facing slopes (0.56 %). The major agents of disturbance on set‐aside fields were moles, rodents (and their predators) and wild boars. In surrounding semi‐natural grasslands, rabbit warrens were common on south‐facing slopes and mound‐building ants on north‐facing slopes. Disturbances were significantly clustered and frequently superimposed.In order to investigate the effects of disturbance quality on plant assemblages in set‐aside fields, two common types of disturbances were compared. These were grazing lawns (0.4–1.0 m2) maintained throughout the summer by common voles (Microtus arvalis), and excavations, 0.7–1.6 m2in area, where wild boars (Sus scrofd) grubbing for food had removed vegetation and top soil in early spring. Both types of disturbances increased plant species richness on the local scale. Wind‐dispersed annual and pauciennial forbs of ruderal habitats (e.g.Carduus acanthoides, Cirsium vulgare, Matricaria maritima, Senecio vernalis) were most abundant on the superficial disturbances made by voles, whereas small, ephemeral field weeds (e.g.Polygonum aviculare, Anagallis arvensis, Chenopodium album, Fallopia convolvulus) predominated on patches grubbed by boars.This study confirms that small‐scale disturbances by animals provide a variety of regeneration niches for field weeds and ruderals. The rate of decline in plant species richness on set‐aside land is likely to be reduced where land is utilized by a variety of herbivorous and soil‐moving mammals.
Biomass and chemical composition of common forest plants in response to fire in western Norway
Authors: Skre Oddvar , Wielgolaski Frans Emil , Moe Bjørn 
Published: May 2006

Abstract. The biomass and chemical composition in six dominant field and bottom layer species was followed during four years after a fire in a Pinus sylvestris forest in western Norway. Three fire intensity levels were distinguished: low, medium and high. The overall biomass in the different species was estimated from the biomass per shoot, the shoot densities in pure stands of the investigated species and the percentage cover at medium burned sites. Corresponding measurements were made at control plots outside the burned area.A strong post‐fire increase in the overall biomass of Calluna vulgaris, Polytrichum spp., Deschampsia flexuosa and Pteridium aquilinum was found, against a much slower regrowth of Vaccinium myrtillus and V. vitis‐idaea. The Vaccinium species and Calluna were the dominant species at the control plot. Accumulation of carbohydrates seemed to take place in green and non‐green tissue of Pteridium and Deschampsia. A corresponding accumulation of nitrogen was found in green and non‐green Calluna and in non‐green Vaccinium myrtillus tissue, and of phosphorus in green and non‐green tissue of both Vaccinium species and Calluna as a result of fire. The regrowth of Calluna was mainly from seeds that appeared to be present in the soil before the fire. The regeneration of Pteridium and the two Vaccinium species took place almost exclusively vegetatively from below‐ground rhizomes that had survived the fire.Three years after the fire the overall biomass at the burned site was higher than at the control site, due to improved light and nutrient conditions. However, the biomass is expected to decrease in the future and the species composition will probably change as nutrients are leached out of the soil and Pinus and deciduous trees (Betula pubescens and Salix caprea) regenerate from seeds and roots, leading to increased competition in the field and shrub layer.
Maintaining and restoring biodiversity in European boreal forests by developing natural disturbance regimes
Authors: Angelstam Per K. 
Published: May 2006

Abstract. A conceptual model is presented as a guide to the maintenance and restoration of ecologically sustainable boreal forest. The model is based on the hypothesis that self‐sustained forest ecosystems can be (re‐)created, and their biodiversity developed, if forest management can simulate the composition and structure of boreal forest landscapes by introducing and maintaining disturbances leading to naturally dynamic spatial and temporal patterns of forest regeneration.The major explanatory variable in the model is the effect of wildfire on sites with different fuel characteristics and climates found in the European boreal forest. Four levels of fire intensity are distinguished, based on mean fire frequencies. These range from extremely low in some wet tall‐herb sites or sites at high altitudes or latitudes with a humid climate, where fire is absent or rare, to dry lichen‐rich sites where fire occurs often. The model is called ASIO, after the words Absent, Seldom, Infrequent and Often, indicating the four levels.Three main disturbance regimes are distinguished in the European boreal forest, based on the complex interactions between probabilistic (e.g. mean fire intervals at different site types) and random events (e.g. where and when a fire occurs): (1) gap‐phase Picea abies dynamics; (2) succession from young to old‐growth mixed deciduous/coniferous forest; and (3) multi‐cohort Pinus sylvestris dynamics. The model stems mainly from studies in Fennoscandia, but some studies from outside this region are reviewed to provide support for a more general application of the model.The model has been implemented in planning systems on the landscape level of several large Swedish forest enterprises, and is also used as an educational tool to help private land owners with the location and realization of forest management regimes. Finally, the model can be used to develop an administrative system for the monitoring of biodiversity in boreal forest.
Does selective defoliation mediate competitive interactions in a semiarid savanna? A demographic evaluation
Authors: Briske D.D. , Hendrickson J.R. 
Published: May 2006

Abstract. Three patterns of target‐neighbor plant defoliation were imposed on a late‐seral, perennial, C4‐grass, Bouteloua curtipendula, in three long‐term grazing regimes to determine the influence of selective defoliation on competitive interactions and species replacement in a semiarid savanna on the Edwards Plateau, Texas, USA. Short‐term (3‐yr) target plant defoliation did not significantly affect either tiller or plant responses in any of the three grazing regimes. Neighbor plant defoliation, either alone or in combination with target plants, produced a significant defoliation interaction with time for tiller number and basal area per plant, but not for tiller recruitment or mortality. The minimal effect of selective defoliation on the intensity of competitive interactions in this semiarid community indicates that selective grazing has a less definitive role in mediating herbivore‐induced species replacement than it does in mesic grasslands and savannas. This interpretation is discussed within the context of long‐term (45‐yr) change in herbaceous vegetation associated with grazing in this community.Cumulative tiller recruitment in the intensively grazed regime was only 44% of that in the ungrazed regime because of greater plant mortality and fewer surviving plants that recruited tillers. Target plant mortality (50%) only occurred in the intensively grazed regime and the proportion of target plants that initiated tillers decreased by 70, 48 and 32% in the ungrazed, moderately and intensively grazed regimes, respectively, during the final two years of the investigation. The decrease in cumulative tiller recruitment in all grazing regimes was probably mediated by a drought‐induced increase in median tiller age the second year of the study. However, tiller per tiller recruitment rate among plants that recruited at least one tiller remained relatively constant among grazing regimes and years. Intensive, long‐term grazing has modified the population structure of this late‐seral perennial grass to the extent that population responses to both herbivory and periodic drought have been altered in comparison with those of ungrazed and moderately grazed populations. Ecological consequences of a herbivore‐induced transition in population structure may be to minimize the effect of selective herbivory on competitive interactions and to function as an avoidance mechanism to reduce the probability of localized population extinction in response to intensive long‐term herbivory.
The response of native species to removal of invasive exotic grasses in a seasonally dry Hawaiian woodland
Authors: D'Antonio Carla M. , Hughes R. Flint , Mack Michelle , Hitchcock Derek , Vitousek Peter M. 
Published: May 2006

Abstract. Non‐native perennial grasses form 30% of the live understory biomass in seasonally dry, submontane forests in Hawaii Volcanoes National Park, yet their effects on native species are unknown. We removed these grasses from plots of 20 m × 20 m in 1991 and maintained removal and control areas over the next three years. Two fast growing shrub species, Dodonaea viscosa and Osteomeles anthylidifolia, increased in size significantly more in removal areas than in controls. Individuals of the most abundant shrub species, Styphelia tameiameia showed no net growth response to grass removal. They did, however, change their architecture: many branches along the mid and upper sections of the main trunk died and a proliferation of new leaves and shoots occurred in the lower 40 cm of trunk. Basal diameter increase was very small in Metrosideros polymorpha, the dominant tree species in these sites.All species except Styphelia had significantly increased leaf tissue nitrogen in removal plots by 18 months after removal when compared to shrubs in control areas suggesting that removal plot shrubs had greater access to soil nitrogen. Available soil‐N pools, which were generally higher in the removal plots, support this interpretation. Light levels near the soil surface were also higher where grasses were removed than where they were present which may have contributed to increased shrub growth. By contrast, soil moisture was consistently lower where grasses were removed than where they were still present. Shrub tissue carbon isotope values were consistent with the interpretation that shrubs in removal plots had less rather than more water available to them. Hence, the increased growth observed in removal plot shrubs could not be due to release from moisture competition.Lastly, our results showed that seedlings of all woody species except Metrosideros were significantly more abundant in removal plots at both one and three years after removal and initially high sapling mortality was balanced by high recruitment into the sapling class. We believe that over time this will result in increased densities of native shrubs if grasses are kept out. With the presence of grasses, shrub growth in these woodlands is reduced and biomass is shifting towards grasses.
Rates of small‐scale species mobility in alvar limestone grassland
Authors: van der Maarel Eddy , Sykes Martin T. 
Published: May 2006

Abstract. Small‐scale species frequency and cumulative species frequency were studied in four plots in limestone grassland of the Veronica spicata‐Avenula pratensis association on Stora Alvaret on the Baltic island of Öland, Sweden. Species mobility was expressed as increase in cumulative species frequency in 20 subplots of 100 cm2. Observed cumulative frequencies from 1985–1989 in all four plots, and from 1985–1995 in one plot were compared with values following from two null models, a ‘minimal mobility’ model and a random mobility model. In ca. 50 % of the cases the observed cumulative frequency was not significantly different from the random expectation. However, in many such cases the mean annual frequency was either very high or very low.Three ways of calculating the mobility rate are presented though only one is used: (observed cumulative frequency ‐lowest annual frequency) / expected cumulative frequency. Values × 100 range from 0 to 100. There were slight differences between the four plots which were interpreted in terms of differences in grazing intensity and soil depth.It is stressed that the idea of the Carousel model has never been meant to suggest that all species would show random mobility, which we now quantify, but that species differ in their mobility rate and that the mean rate is much higher than generally realized.
Euthymos of Locri: a case study in heroization in the Classical period
Authors: Currie Bruno 
Published: May 2006

AbstractEuthymos was a real person, an Olympic victor from Locri Epizephyrii in the first half of the fifth century BC. Various sources attribute to him extraordinary achievements: he received cult in his own lifetime; he fought with and overcame the ‘Hero of Temesa’, adaimonwho in ritual deflowered a virgin in the Italian city of Temesa every year; and he vanished into a local river instead of dying (extant iconography from Locri shows him as a river god receiving cult a century after his death). By taking an integrative approach to Euthymos' legend and cult iconography, this article proposes a new interpretation of the complex. It is argued that Euthymos received cult already in his lifetime in consequence of his victory over the Hero and that he took over, in a modified form, the Hero's cult. Various considerations, including the role of river gods as the recipients of brides' virginity in prenuptial rites, point to an identification of the Hero as a river deity. In this light it is suggested that the contest between Euthymos and the Hero was conceived as a deliberate emulation of Herakles' fight with Acheloos. The case of Euthymos at Locri, for all its peculiarities, draws our attention to some important aspects of the heroization of historical persons in the Classical period. First, the earliest attested cult of a living person in Greece is to be placed around the middle of the fifth century. Second, heroized persons in the Classical period were not always passive in the process of their heroization, but could actively promote it. And third, a common pattern in the heroization of contemporaries in the Classical period was to accommodate them into existing cults.
A note on the Berber head in London
Authors: Roller Duane W. 
Published: May 2006

AbstractThe well-known ‘Berber Head’ in the British Museum, found at Kyrene in 1861, has long defied exact stylistic analysis. Its findspot provides no precise date, and ever since the excavators suggested that it was a piece from the fourth century BC, this dating has been sustained, generally through inertia. Yet recent scholars have become increasingly aware of the weakness of this date without offering specific alternatives other than a gradual down-dating. Its North African features indicate that it is a portrait of an indigenous ruler, and thus attribution must be based on the likelihood of such a person being honoured in Kyrene. It is herein suggested that it is a portrait of the Numidian prince Mastanabal, son of Massinissa, and that it dates to the time that Massinissa was a close associate of the king of Kyrene, the future Ptolemaios VIII of Egypt, or 163–148 BC. Mastanabal was a noted athlete and thus the piece may be a commemoration of one of his victories. Its commissioning would fit into his father's vigorous hellenization policy. Although the style remains difficult of analysis, certain features, especially the beard under the chin, support a second-century BC date.
Cut Elimination in the Presence of Axioms
Authors: Negri Sara , von Plato Jan 
Published: May 2006

AbstractA way is found to add axioms to sequent calculi that maintains the eliminability of cut, through the representation of axioms as rules of inference of a suitable form. By this method, the structural analysis of proofs is extended from pure logic to free-variable theories, covering all classical theories, and a wide class of constructive theories. All results are proved for systems in which also the rules of weakening and contraction can be eliminated. Applications include a system of predicate logic with equality in which also cuts on the equality axioms are eliminated.
From Stability to Simplicity
Authors: Kim Byunghan , Pillay Anand 
Published: May 2006

§1. Introduction. In this report we wish to describe recent work on a class of first order theories first introduced by Shelah in [32], the simple theories. Major progress was made in the first author's doctoral thesis [17]. We will give a survey of this, as well as further works by the authors and others.The class of simple theories includes stable theories, but also many more, such as the theory of the random graph. Moreover, many of the theories of particular algebraic structures which have been studied recently (pseudofinite fields, algebraically closed fields with a generic automorphism, smoothly approximable structures) turn out to be simple. The interest is basically that a large amount of the machinery of stability theory, invented by Shelah, is valid in the broader class of simple theories. Stable theories will be defined formally in the next section. An exhaustive study of them is carried out in [33]. Without trying to read Shelah's mind, we feel comfortable in saying that the importance of stability for Shelah lay partly in the fact that an unstable theory T has 2λ many models in any cardinal λ ≥ ω1 + |T| (proved by Shelah). (Note that for λ ≥ |T| 2λ is the maximum possible number of models of cardinality λ.)
Towards a Re-Evaluation of Julius König's Contribution to Logic
Authors: Franchella Miriam 
Published: May 2006

AbstractJulius König is famous for his mistaken attempt to demonstrate that the continuum hypothesis was false. It is also known that the only positive result that could have survived from his proof is the paradox which bears his name. Less famous is his 1914 bookNeue Grundlagen der Logik, Arithmetik und Mengenlehre. Still, it contains original contributions to logic, like the concept of metatheory and the solution of paradoxes based on the refusal of the law of bivalence. We are going to discover them by analysing the content of the book.
Between Russell and Hilbert: Behmann on the Foundations of Mathematics
Authors: Mancosu Paolo 
Published: May 2006

AbstractAfter giving a brief overview of the renewal of interest in logic and the foundations of mathematics in Göttingen in the period 1914-1921, I give a detailed presentation of the approach to the foundations of mathematics found in Behmann's doctoral dissertation of 1918, Die Antinomie der transfiniten Zahl und ihre Auflösung durch die Theorie von Russell und Whitehead. The dissertation was written under the guidance of David Hilbert and was primarily intended to give a clear exposition of the solution to the antinomies as found in Principia Mathematica. In the process of explaining the theory of Principia, Behmann also presented an original approach to the foundations of mathematics which saw in sense perception of concrete individuals the Archimedean point for a secure foundation of mathematical knowledge. The last part of the paper points out an important numbers of connections between Behmann's work and Hilbert's foundational thought.
Metropolitanus Campus
Authors: Ramsay W. M. 
Published: May 2006

It may not be unsuitable to the purpose of this Journal to depart for once from the strictly scientific method, and describe shortly the problem of a ‘Lost Phrygian City,’ as it presents itself to the explorer both in its relation to ancient literature and in its actual modern features. I take the example of a city which played no part in ancient history, which is mentioned only twice or thrice incidentally in classical literature, where no known event took place and no person known to fame was born, which, in short, is about as insignificant as a city could well be, and I hope to show that the discovery even of such a little city may have interest and value for classical scholars.The passage in which Livy describes the march of the consul Manlius on his piratical raid through Asia Minor is one of peculiar interest on many grounds, apart from its value for students of geography. There is no passage in the whole of Livy which is more obviously translated from a Greek original: it is therefore of great importance in the question of his relation to his authorities and of his trustworthiness in using them. Beyond the mere resolution of the true scholar to understand his author, there is the further incentive to study this particular passage that the author's historical character is to some extent dependent on it. Now the third recorded stage beyond Sagalassos in Manlius's march is the Metropolitanus Campus. Where in wide Phrygia was the Metropolitanus Campus?