bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inaccurate, Exceptional, One-Sided or Irrelevant? The Debate about the Alleged Decline of Social Capital and Civic Engagement in Western Societies
Authors: STOLLE DIETLIND , HOOGHE MARC 
Published: December 2004

In his 1790 address to the Académie Française in Paris, Condorcet noted that every new generation has a tendency to accuse itself of being less civic-minded than previous cohorts. Two centuries later, this argument has once again regained front-page status. The debate is currently focused on the question of whether or not social capital and civic engagement are declining in Western societies. In his academic best-seller Bowling Alone, Robert Putnam argues that younger age cohorts, socialized in the prosperous economic conditions of the 1960s and onwards, are less inclined to engage in community life and in politics, and also less likely to trust their fellow citizens. By contrast, the ‘long civic generation’, born roughly between 1910 and 1940, is portrayed as much more motivated in these respects. They readily volunteer in community projects, read newspapers and take on more social responsibilities. In this view, a process of generational replacement is responsible for a steady decline of social capital and civic engagement in American society. As the long civic generation is replaced by younger age cohorts, the social capital stock of American communities slowly diminishes. The indicators used to substantiate this claim are numerous and diverse: measures for voter turnout, attendance of club meetings, generalized trust, the number of common family dinners, the number of card games played together, and even respect for traffic rules. All of these attitudes and behaviours, it is argued, depict a significant downward trend.Although Putnam is by far the most vocal of all scholars in the ‘decline of social capital’ choir, he certainly is not the only author describing an erosion of traditional societal relations.
To Adopt or Not to Adopt Proportional Representation: The Politics of Institutional Choice
Authors: BLAIS ANDRÉ , DOBRZYNSKA AGNIESKA , INDRIDASON INDRIDI H. 
Published: December 2004

In September 1864, the Association Internationale pour le Progrès des Sciences Sociales met in Amsterdam to examine the system of proportional representation (PR) which had just been proposed by Thomas Hare. The meeting signalled a growing interest in systems of PR across the more democratic nations of the world – some of which had already begun experimenting with it. Sixty years later, the majority of existing democracies, including Austria, Denmark, Finland, France, Germany, Ireland, Italy, Luxemburg, Malta, Netherlands, Norway, Sweden and Switzerland, had adopted PR for the election of their national legislatures.Why did so many countries decide to shift to PR? Why did the shift occur at a given point in time, not earlier or later? Why did some countries never move to PR? These are the questions that we address in this Note.We are interested in exploring the factors that influenced the decision to adopt PR at the turn of the twentieth century. We argue that two factors of considerable theoretical relevance were particularly important in facilitating the shift to PR: the spread of democratic ideas and the presence of a majority (usually two-round) system and, as a consequence, a multi-party system.Carstairs's classic history of electoral systems shows that at the turn of the twentieth century there was a strong demand for PR, which was linked to a more general demand for democratization. As Carstairs notes,there was a general movement in the direction of more democratic political institutions which took several different forms … There was a movement for the establishment or strengthening of parliamentary institutions … Extensions of the franchise for parliamentary elections enabled an increasingly large proportion of the population to gain representation in parliament … With these developments it became a matter of increasing concern that the elected members of parliament and the parties they supported should fairly represent the various interests and opinions of the electorate.
Tropical forest tree mortality, recruitment and turnover rates: calculation, interpretation and comparison when census intervals vary
Authors: LEWIS SIMON L. , PHILLIPS OLIVER L. , SHEIL DOUGLAS , VINCETI BARBARA , BAKER TIMOTHY R. , BROWN SANDRA , GRAHAM ANDREW W. , HIGUCHI NIRO , HILBERT DAVID W. , LAURANCE WILLIAM F. , LEJOLY JEAN , MALHI YADVINDER , MONTEAGUDO ABEL , NÚÑEZ VARGAS PERCY , SONKÉ BONAVENTURE ,   NUR SUPARDI, M.N.  , TERBORGH JOHN W. , VÁSQUEZ MARTÍNEZ RODOLFO 
Published: December 2004

Summary

Mathematical proofs show that rate estimates, for example of mortality and recruitment, will decrease with increasing census interval when obtained from censuses of non‐homogeneous populations. This census interval effect could be confounding or perhaps even driving conclusions from comparative studies involving such rate estimates.
We quantify this artefact for tropical forest trees, develop correction methods and re‐assess some previously published conclusions about forest dynamics.
Mortality rates of > 50 species at each of seven sites in Africa, Latin America, Asia and Australia were used as subpopulations to simulate stand‐level mortality rates in a heterogeneous population when census intervals varied: all sites showed decreasing stand mortality rates with increasing census interval length.
Stand‐level mortality rates from 14 multicensus long‐term forest plots from Africa, Latin America, Asia and Australia also showed that, on average, mortality rates decreased with increasing census interval length.
Mortality, recruitment or turnover rates with differing census interval lengths can be compared using the mean rate of decline from the 14 long‐term plots to standardize estimates to a common census length using λcorr = λ × t0.08, where λ is the rate and t is time between censuses in years. This simple general correction should reduce the bias associated with census interval variation, where it is unavoidable.
Re‐analysis of published results shows that the pan‐tropical increase in stem turnover rates over the late 20th century cannot be attributed to combining data with differing census intervals. In addition, after correction, Old World tropical forests do not have significantly lower turnover rates than New World sites, as previously reported. Our pan‐tropical best estimate adjusted stem turnover rate is 1.81 ± 0.16% a−1 (mean ± 95% CI, n = 65).
As differing census intervals affect comparisons of mortality, recruitment and turnover rates, and can lead to erroneous conclusions, standardized field methods, the calculation of local correction factors at sites where adequate data are available, or the use of our general standardizing formula to take account of sample intervals, are to be recommended.
Nutrient limitation of plant growth and forage quality in Arctic coastal marshes
Authors: NGAI JACQUELINE T. , JEFFERIES ROBERT L. 
Published: December 2004

SummaryForaging by geese has led to vegetation loss in salt marshes along the Hudson Bay coast and lesser snow geese are increasingly grazing inland freshwater marshes. We determined whether different nutrients limit the growth of forage plants in the two habitats, and whether these differences affect the nutritional quality of vegetation available to geese at La Pérouse Bay, Manitoba.Results from fertilization experiments indicate that primary productivity in the salt marsh is both nitrogen and phosphorus limited, whereas the freshwater marsh is phosphorus limited. Total amounts of calcium, magnesium and potassium in above‐ground biomass per unit area showed similar differences in limitation.Leaves of preferred forage species have higher nutrient concentrations (nitrogen, phosphorus, calcium, potassium, magnesium, sodium) and lower C : N and C : P ratios than alternative forage. The main forage species in the salt marsh (Puccinellia phryganodes) has higher nutrient content per unit mass, for nitrogen, magnesium, calcium and sodium, than the major freshwater marsh species(Carex aquatilis). The difference in nutritional quality of forage between the marshes is likely to have had consequences for goose fitness, and may have contributed to the reported declines in gosling survivorship and size.At moderate grazing intensities, seasonal growth of salt‐marsh forage is maintained by addition of nitrogen and, to a lesser extent, phosphorus from high numbers of goose faeces to swards. In contrast, the low densities and low phosphorus content of goose faeces in the phosphorus‐limited freshwater marsh mean that plants are unlikely to recover rapidly from the effects of grazing. As a consequence, the freshwater marsh is likely to become increasingly less productive as foraging intensifies.Nutrient gradients in vegetation across an ecotone and changes in foraging behaviour have resulted in adverse effects on both the growth rates of individuals and the population structure of a herbivore.
Regulation of anti‐herbivore defence by Fucus vesiculosus in response to various cues
Authors: ROHDE SVEN , MOLIS MARKUS , WAHL MARTIN 
Published: December 2004

Summary

We examined whether the marine macroalga Fucus vesiculosus induces defences against herbivory and, if so, which factors trigger this induction. In addition, we assessed whether induced defences are reduced after consumption stops.
Induced effects were measured as changes in palatability rather than changes in the chemistry of the algae. We also tested for reductions in growth rate to determine whether induced defence incurs metabolic costs.
We tested whether direct grazing, feeding on neighbouring plants, clipping and presence of a non‐grazing herbivore could trigger induction. The isopod Idotea baltica and the gastropod Littorina littorea were used as herbivores.
Both direct feeding of I. baltica and feeding on neighbouring plants induced chemical defence in F. vesiculosus, whereas the snail L. littorea only induced defence by direct grazing. Simulated herbivory (clipping), or the presence of herbivores without grazing, did not lead to defence induction. All induced defences were reversed within 2 weeks of consumption ending.
Thus, F. vesiculosus differentiates between physical damage and natural herbivory. Furthermore, feeding by I. baltica on F. vesiculosus releases signals that trigger neighbouring Fucus individuals to induce defence.
We found no evidence that metabolic costs incurred as a consequence of induced defence were sufficient to lead to growth reduction.
This algal species demonstrates defence plasticity (i.e. induction and reduction of anti‐herbivore defences ‘on demand’), with the response depending on both grazer identity and grazing pattern matter.
Leaf area and growth of juvenile temperate evergreens in low light: species of contrasting shade tolerance change rank during ontogeny
Authors: LUSK C. H. 
Published: December 2004

Summary

Interspecific variation in leaf life span of woody plants should have important consequences for ontogenetic variation in biomass distribution, and hence carbon balance, in low light. This proposal was examined by measuring foliage turnover, growth, biomass allocation and biomass distribution of juveniles (25–1180 mm tall) of four evergreens differing in shade tolerance, growing in low light (2–5% canopy openness) in temperate rainforest understoreys in south‐central Chile.
As predicted, ontogenetic trends in leaf area ratio (LAR) of two very shade‐tolerant species with long‐lived leaves (Aextoxicon punctatum and Myrceugenia planipes) contrasted strongly with those of mid‐tolerant Eucryphia cordifolia and intolerant Aristotelia chilensis. Low‐light LAR fell rapidly with increasing plant size in Eucryphia and Aristotelia, but was size‐invariant in the two shade‐tolerant taxa. As a result, although small seedlings of Eucryphia and Aristotelia displayed more leaf area than shade‐tolerant seedlings of similar size (largely because of differences in specific leaf area), this relationship was reversed for plants over ≈500 mm tall.
Although the slower foliage turnover of the shade‐tolerant species at least partly explains this reversal, allocational differences may also be involved. Root mass fraction of both shade‐tolerant species was significantly negatively correlated with size, possibly reflecting declining allocation to roots in larger plants. In contrast, root mass fraction was not correlated with size in Eucryphia or Aristotelia.
Above‐ground relative growth rate in low light followed similar ontogenetic trends to LAR, declining more quickly in light‐demanding species than in shade‐tolerant associates. As a result, large seedlings (>400 mm tall) of shade‐tolerant Myrceugenia and Aextoxicon grew more quickly than their light‐demanding associates at the same height. The steeply declining LAR and growth of Eucryphia and Aristotelia suggest that these taxa will eventually die of energy starvation in low light.
Results are consistent with the idea that accumulation of an extensive leaf area eventually gives juvenile shade‐tolerant evergreens a net carbon gain advantage over their light‐demanding associates in low light. Awareness of long‐term ontogenetic trends will enhance understanding of relationships of shade‐tolerance variation with morphology and growth of woody evergreens.
Sprouting by plants: the effects of modular organization
Authors: VESK P. A. , WESTOBY M. 
Published: December 2004

Summary

Plant survival following disturbance was modelled simply as the probability that at least one of n stems sprouts, each stem having an independent probability of sprouting, s. This first‐order model with any stem on any plant in any species having probability s = 0·18 of sprouting after clipping (s = 0·09 after burning) explained nearly half of the deviance associated with species’ mortality in a field experiment on 43 species from a range of growth forms.
Allowing species to take either a low or high per‐stem sprouting probability (SSP) improved statistical explanation substantially. Fitting growth form SSP was less effective, showing that much of the apparent among‐species variation in SSP was within growth forms.
Allowing each species to have a different SSP essentially provided a saturated model. The estimated species‐specific probabilities were positively related to the depth from which sprouts could emerge after disturbance. Predicting species’ bud depth from some simply measured morphological trait would be a considerable advance. Limited evidence suggested that sprout depth was associated with thick or dense leaves (low specific leaf area and leaf water content).
Depicting plants as a collection of independent stems with equal probability of sprouting appears a reasonable first‐order model for whole‐plant sprouting, despite being morphologically simplified.
Leaf digestibility and litter decomposability are related in a wide range of subarctic plant species and types
Authors: CORNELISSEN J. H. C. , QUESTED H. M. , GWYNN‐JONES D. , VAN LOGTESTIJN R. S. P. , DE BEUS M. A. H. , KONDRATCHUK A. , CALLAGHAN T. V. , AERTS R. 
Published: December 2004

SummaryHerbivory and litter decomposition are key controllers of ecosystem carbon and nutrient cycling. We hypothesized that foliar defences of plant species against vertebrate herbivores would reduce leaf digestibility and would subsequently, through ‘afterlife effects’, reduce litter decomposability.We tested this hypothesis by screening 32 subarctic plant species, belonging to eight types in terms of life form and nutrient economy strategy, for (1) leaf digestibility in cow rumen juice; (2) biochemical and structural traits that might explain variation in digestibility; and (3) litter mass loss during simultaneous incubation in an outdoor subarctic litter bed.Interspecific variation in green‐leaf digestibility corresponded significantly with that in litter decomposability; this relationship was strongly driven by overall variation among the eight plant types (r = 0·92). The same relationship was not detectable within plant types in taxonomic relatedness tests.Several biochemical and structural parameters (phenol‐to‐N ratio, lignin‐to‐N ratio) explained a significant part of the variation in leaf digestibility, but again only between and not within plant types.Our results provide further support for the role played by foliar defence in the link between plant and soil via the decomposition pathway. They are also a new example of the potential control of plant functional types over carbon and nutrient dynamics in ecosystems.
Environmental severity and variation in the reproductive traits of Impatiens glandulifera
Authors: WILLIS S. G. , HULME P. E. 
Published: December 2004

Summary

Seed mass is widely regarded as a key plant trait, yet is notoriously variable within an individual species. This study reports the first field experiments to disentangle the relative importance of four major correlates of seed mass variation: resource limitation; plant height; seed number; and seasonality.
Variation in reproductive traits in Impatiens glandulifera Royle was partitioned among six populations established across an elevation gradient, among plants at each elevation and within individual plants.
Seed mass was the least variable trait both at the individual and population levels, while the number of pods per plant varied most. Seed mass variation was greatest among individual plants (42%) and was least among populations (28%).
Taller plants produced proportionally more seed pods and more seeds per pod. Seed mass was not related to the number of pods per plant, or the number of seeds per pod. Thus with increasing resources, I. glandulifera allocated resources to produce more seeds rather than larger seeds.
Seed mass was negatively correlated with the heat sum over the period of seed maturation, explaining increased seed mass at higher elevations and increasing seed mass over time at most elevations. This may indicate that environmental condition pre‐ and post‐fertilization determines the relationship between seed mass and elevation, thereby limiting the potential for evolutionary selection for seed‐size optima.
The study warns against correlative studies of seed mass variation that select arbitrary populations or ignore the temporal dynamics in seed mass, as these may generate spurious correlations among life‐history traits.
The success of I. glandulifera as an invasive species may reflect the extended period of seed release, considerable seed mass variation and large seed size under conditions of environmental severity. These traits will facilitate the exploitation of spatially and temporally heterogeneous natural environments commonly found in riparian ecosystems.
Body size and mating strategies in the simultaneous hermaphroditeOxynoe olivacea(Mollusca, Opisthobranchia, Sacoglossa)
Authors: GIANGUZZA P. , BADALAMENTI F. , JENSEN K. R. , CHEMELLO R. , CANNICCI S. , RIGGIO S. 
Published: December 2004

SummaryTo better understand the role and importance of body size in hermaphroditic mating system theory, the mating behaviour of the shelled sacoglossanOxynoe olivaceawas studied. This simultaneous hermaphrodite exhibits bilateral and unilateral sperm transfer and thus it is particularly suitable for studies on hermaphrodite sexual conflict.In this study three hypotheses on body size were tested: thatO. olivaceapartner size has an effect on (i) mating mode choice, (ii) duration of mating modes, and (iii) choice of sexual role. Furthermore, we tested Charnov's hypothesis that inO. olivacea, like many simultaneous hermaphrodites, a sexual conflict exists and the male role is preferred.A laboratory experiment was done to test the aforementioned hypothesis and to observe the general mating behaviour ofO. olivacea. Pairs of similar (S) and different (D) sizes were considered for a total of five different treatments (S1, S2, S3, D1, D2).During the five copulatory treatmentsO. olivaceamated up to 93 times. Specifically, pairs of the same size mated with bilateral sperm transfer while unilateral copulation was common in pairs of slightly differing size. Contrary to predictions, animals of small body size started mating in the female role.O. olivaceashowed an active alternation of sexual roles and thus did not specialize in one particular sexual role.This study produced evidence of a relationship between mating mode and body size inO. olivaceaand highlighted the need for new studies on this simultaneously hermaphroditic species.
Aerodynamics of wind pollination in a zoophilous flower, Brassica napus
Authors: CRESSWELL J. E. , DAVIES T. W. , PATRICK M. A. , RUSSELL F. , PENNEL C. , VICOT M. , LAHOUBI M. 
Published: December 2004

Summary

The flower of Brassica napus L. appears to be typically zoophilous (suited to animal pollination) because of its visually attractive petals, robust stigma and nectaries. Pollination by wind is feasible, however, and its likely effectiveness is not immediately foreseeable because of the complexity of interactions between objects and windborne particles.
Computational fluid dynamics (CFD) and wind‐tunnel experiments were used to investigate the aerodynamic interactions between the flower and a windborne suspension of its pollen.
The flower's petals handicapped wind pollination by reducing the target efficiency of the upwind‐facing stigma. For downwind‐facing flowers, pollen reception was negligible.
Several aspects of the plant's architecture (floral structure, pollen cohesiveness, inflorescence structure) are uncompromisingly zoophilous. Estimates of the amount of wind pollination suggest that it is unlikely to be important for the long‐distance dispersal of B. napus genes such as those from genetically modified varieties.
This study illustrates how CFD may become a powerful tool in future analyses of wind pollination.
Respiration and thermogenesis by cones of the Australian cycad Macrozamia machinii
Authors: SEYMOUR R. S. , TERRY I. , ROEMER R. B. 
Published: December 2004

Summary

While cycads are often considered to be wind‐pollinated, it is now clear that insects are pollen vectors in many species. This study addresses the role of thermogenesis in pollination biology of the dioecious cycad Macrozamia machinii P.I. Forster & D.L. Jones.
The patterns of thermogenesis in intact male and female cones were assessed with thermometry and respirometry throughout the pollination period in the field.
Thermogenic episodes in male cones occurred from about 17.00–00.00 h on successive evenings, in association with dehiscence of sporangia and presence of their pollinating weevils (Tranes sp.).
Temperatures of the 167 g male cones rose ≈6 °C above ambient, and mean rate of oxygen consumption peaked at 7·7 µmol s−1 (3·6 W). Regulation of male cone temperature was not evident, and thermogenesis of female cones was insignificant.
Male cones probably heat to augment scent production and enhance weevil activity, including mating and egg‐laying, but female cones may benefit from reduced visitation and freedom from damage by weevil larvae. Male cones may be sacrificial in providing the reward to the pollinators while the female cones are safeguarded.