bluuebunny/crossref_metadata_2025 huggingface dataset:
A Simulation Model for Life Cycle Project Management
Authors: Jaafari Ali , Kumar Doloi Hemanta
Published: December 2004

This paper puts forward a simulation model specifically designed for holistic evaluation of project functionality within a life cycle project management framework. The authors describe a methodology for development of the aforementioned tool, referred to as a dynamic simulation modeling system (DSMS). The DSMS is geared toward modeling of service and manufacturing processes with hierarchical and modular modeling methodology; however, the underlying philosophy can be adopted for modeling any generic system. The enhanced modeling features and logical division of large systems into small process components and their internal linkage are the key contributions of this work. The aim of this development is to apply the simulation technique in order to evaluate the overall project functionalities from the dynamic business perspective. A set of business objective functions (i.e., life cycle objective function [LCOF]) has been employed as a basis for decision making throughout the project’s life. Object‐oriented programming language with the object‐oriented database technology facilitates the necessary model capability. A brief case study has been used to demonstrate and discuss the model capability.
Optimal Strategies for Highway Pavement Management in Developing Countries
Authors: Tsunokawa Koji , Riaz‐ul‐Islam  , Changyu Guan
Published: December 2004

Highway pavement design in developing countries is usually based on standards borrowed from industrialized countries. However, it may not be economically feasible to use these high design standards in developing countries, because of significant differences in socioeconomic conditions. Using the World Bank’s highway design and maintenance standards model (HDM‐III), this paper investigates optimal pavement design and its relationship with the developmental stage of a country. Optimal pavement design can be defined as that which minimizes total transport costs to society, which comprise the sum of agency costs and road user costs. Basic data for the analysis were derived from Chinese conditions, and appropriate adjustments were made to model five classes of hypothetical countries in different developmental stages. It is shown that the optimal trade‐off between initial expenditure on construction and subsequent maintenance depends on the developmental stage of an economy. The same high design standards that are suitable for industrialized countries may not be economically justified in developing countries. Developing countries should start with modest pavements and then spend more on maintenance afterwards, which is an overdue, neglected priority today.
Quantitative Method for Evaluation and Analysis of Canals
Authors: Yan Li , Sato Seiji
Published: December 2004

Previous methods for the evaluation of urban spaces use a qualitative analysis of visual and intuitive sensations. In this paper, a quantitative method for the analysis, evaluation, and adjustment of canal spaces by means of fluctuation theory is proposed. The proposed method consists of two sections, (1) quantitative analysis for evaluation of the canal, and (2) application of quantitative guidelines for the redevelopment of existing canals such that the characteristics of a 1/f fluctuation are maintained. The results of the application of the technique on a canal in China verify the applicability of the method and demonstrate its usefulness in urban planning.
Multicriteria Planning of Post‐Earthquake Sustainable Reconstruction
Authors: Opricovic Serafim , Tzeng Gwo‐Hshiung
Published: December 2004

A multicriteria model is developed for analyzing the planning strategies for reducing the future social and economic costs in the area with potential natural hazard. The developed multicriteria decision‐making procedure consists of generating alternatives, establishing criteria, assessment of criteria weights, and application of the compromise ranking method (VIKOR). The alternatives are the scenarios of sustainable hazard effects mitigation, generated in the form of comprehensive reconstruction plans, including the redevelopment of urban areas and infrastructures, multipurpose land use, and restrictions on building in hazardous areas. The plans have to be evaluated according to the criteria representing public safety, sustainability, social environment, natural environment, economy, culture, and politics. The multicriteria model can treat all relevant conflicting effects and impacts in their representative units. The evaluation of alternatives is implicated with imprecision (or uncertainty) of established criteria, and the fuzzy multicriteria model is developed to deal with “qualitative” (unquantifiable or linguistic) or incomplete information. The application of this model is illustrated with the post‐earthquake reconstruction problem in Central Taiwan, including the restoration concerning the safe and serviceable operation of “lifeline” systems, such as electricity, water, and transportation networks, immediately after a severe earthquake.
A Dynamic Model for the Cross‐sectional Distribution of Unemployment Rates
Authors: Hashemi Fariba
Published: December 2004

This paper proposes a model to describe the continuous time‐evolution of density of the cross‐sectional distribution of unemployment rates. The model is founded on the theory of analytical diffusion processes. The steady‐state distribution as well as the dynamic behaviour of the model are analytically derived. Parameters in the resulting analytical expressions are then fitted to US regional data. The empirical portion of the paper illustrates the usefulness of modeling the temporal evolution of the cross‐sectional distribution of unemployment rate, rather than simply attending to equilibrium implications of the process.
Profit Sharing in Portugal: Why Higher Productivity?
Authors: Moura Ramos Luis
Published: December 2004

The paper studies some characteristics of Portuguese profit‐sharing (PS) firms based on a sample of 192 manufacturing firms. Some issues are examined that could help explain observed productivity differences such as the performance contingency of PS payments and the complementary or substitution nature of these payments regarding wages. The higher productivity found for PS firms seems to be more related to higher total remuneration in these firms than to the specific PS pay formula. The issues of why, how and by whom PS payments are determined could clarify the exact nature of our findings.
An Econometric Analysis of Strike Activity in the Brazilian Industrial Sector
Authors: Picchetti Paulo
Published: December 2004

A data set on strike activity for Brazil during the period between 1983 and 1993 is used to produce results based on statistical methods of frequency and duration analysis. The obtained results of frequency and duration of strikes, including their relationships with some macroeconomic variables, are compared with ones from similar studies using data from the USA and Canada. The comparison shows that there seems to be a common pattern of results in these countries. An explanation for the observed features of these patterns is then sought in the context of game‐theoretic models of bargaining, and suggestions for future research in the area are given.
Financing Constraints and Investment Decline in Mexico
Authors: İşan Talan B.
Published: December 2004

To what extent can financing constraints, which have been so central to foreign‐debt‐related explanations of investment decline in heavily indebted economies, account for low investment rates in Mexico after 1982? In order to investigate the implications of the financing constraints hypothesis on investment decisions, this study employs a cost‐of‐adjustment model of investment and annual panel data of Mexican manufacturing industries covering the period 1970–90. It is found that some of the debt crisis effects on investment, identified in the earlier literature, may be due to binding financing constraints in Mexico.
‘The Women Can Be Moved to Fill in the Gaps’: New Production Concepts, Gender and Suppliers
Authors: Newsome Kirsty
Published: December 2004

This article wishes to extend our understanding of New Production Concepts (hereafter NPC) induced restructuring in two areas. Firstly, it wishes to further explore the gender distinctions to be made when considering the impact of NPC on the labour process. In turn, this calls for a consideration of the extent to which NPC restructuring perpetuates, recasts and fortifies gendered divisions of labour within organizations. It will indicate how the introduction of NPC within a buyer and two supply organizations intensified prevailing gendered divisions of labour and disproportionately impacted upon women workers. It will also stress that women workers appeared to be more exposed to the implementation of policies designed to secure responsiveness to the satisfaction of customer requirements. However, while the evidence will reveal the importance of exploring distinctions within labour as part of a process of restructuring, it also highlights the linkages between these organizations. Secondly, therefore it aims to extend the territory of existing debates by highlighting a gender distinction across and between organizations. It will conclude by highlighting the importance of constructing an analysis of NPC‐induced restructuring which not only embraces a gendered analysis of change but simultaneously does not privilege research attention to particular ‘hermetically sealed’ workplaces, dislocated from a wider process of inter‐firm restructuring.
Gender‐Related Opportunities and Turnover: The Case of Medical Sector Employees
Authors: Mano‐Negrin Rita
Published: December 2004

This study examined the relationships between gender, objective and perceived work‐related opportunities, and turnover behavior. This was achieved using an interdisciplinary approach that combined the macro‐level perspective on opportunities in internal and external labor markets, with the micro‐level perspective of individual perceptions of opportunities. The results revealed that the opportunities–turnover linkage is gender‐specific rather than gender‐neutral. Women's turnover behavior was affected by their ‘perception’ of employment opportunities in the organizational and local labor markets. By contrast, men's turnover behavior was affected by ‘objective’, organizational and local labor market conditions. These findings indicate that the objective opportunities of the work market may be compatible with men’s, but not women’s, work needs and hence question existing assumptions of a ‘gender‐neutral’ effect of opportunities on turnover decisions.
Prospects for Change? Structural, Cultural and Action Dimensions of the Careers of Pioneer Women Priests in the Church of England
Authors: Bagilhole Barbara
Published: December 2004

Like other organizations the Church of England has adapted to the greater and increasing involvement of women in paid work and other parts of the public domain. However, this has been a gradual, strongly contested and painful process for the Church. In 1986, it allowed women to enter the lowest rank of the clerical profession as deacons, and after many years of hard and bitter struggle the vote was won in the General Synod to ordain women to the priesthood.1 The first women priests were ordained in 1994. This article reports a study of 31 of the most senior and experienced Church of England women priests from dioceses across the whole of England.

Women entering previously male‐dominated, or male exclusive occupations as in the case of the priesthood, are necessarily engaged in a process of change. The women priests in this study were active agents for change, they wanted to change the organization, both structurally and culturally. This article examines the question of whether these women ‘pioneers’ in the Church of England stand any chance of changing the organization and the occupation, or whether and to what extent they are changed themselves by needing to ‘fit in’. It will look at the structural and cultural factors, which may inhibit their agency or support it.
Sex Discrimination in UK Academia
Authors: Knights David , Richards Wendy
Published: December 2004

This article examines the gendered nature of employment in UK universities, showing women's experience of discrimination through differences in contract status and in access to academic hierarchies. It argues that the typical academic career path is structured according to a male perception of success: research‐active, participating in the Research Assessment Exercise, an uninterrupted career history. The system of meritocracy upon which appointment and promotion within academic are based, the article argues, reinforces such a masculine approach to career success. These meritocratic systems of inequality reflect and reproduce the discursive practices of masculinity that present disadvantages to a majority of women and some men.
Swedish Bureaucracy in an Era of Change
Authors: Ehn Peter , Isberg Magnus , Linde Claes , Wallin Gunnar
Published: December 2004

Swedish bureaucracy combines some structural peculiarities founded on constitutional traits from the 17th century with a clear formal division of labor between the national and local levels from the late 19th century. These structures have mainly remained unchanged during periods of strong expansion in the first post‐WWII decades and preconditions for shrinking during the 1980s and 1990s. In this article, we highlight how these changes have put stress on the bureaucracy and the public sector in general, and how demands for reform and adapting have been managed and viewed by the administrative and political camps, respectively. Social, educational, and political changes among Swedish bureaucrats and their roles are presented and analyzed. The national bureaucracy has “muddled through” and has not been subjected to radical reforms. Its working is still approved—though by no means regarded as sacred—by its administrative agents and its political principals.
Creating attractive services which citizens want to attend
Authors: Weeks Wendy
Published: December 2004

This paper reviews the available literature on the importance of the physical environment in service delivery, and then develops a framework of nine elements for creating user‐friendly human services.
Identity and everyday experiences of homelessness: Some implications for social work
Authors: Zufferey Carole , Kerr Lorraine
Published: December 2004

It is important for the complexities of homelessness to be considered when constructing policy or practice relating to people who are without safe and stable accommodation. These complexities can be loosely categorised around the definitions, causes and experiences of homelessness. While definitions and causes are topics of current debates, study of the lived‐experiences of homelessness remains an area that is largely under‐researched. This paper explores some of the implications for social work and social workers when the individual's understanding and experience of her/his identity as a ‘homeless person’ and consequent relationships with service providers are not factored into policy and practice. This article draws on the findings of a study of homeless adults in inner city Adelaide to illustrate the author's arguments. It outlines the importance of listening to service users' perspectives in order to assess whether dominant constructions of social work, homelessness and ‘homeless people’ are meeting the needs of and improving outcomes for individual clients. More broadly, it is hoped that making these perspectives visible will assist in the development of ‘client‐focused’ practice and policy.
Untreatable families? Suggestions from literature
Authors: Brydon Kerry
Published: December 2004

The purpose of this paper is to highlight insights from literature, which suggest that some families are unable to respond to intervention and treatment. Discussion of this aspect of family functioning is notably missing from the discourse on family preservation. There will be an outline offered of the factors that may be contributing to this reality, one consequence being that children wait indefinite periods of time for lasting arrangements to be formulated for their future. Suggestion will be offered as to how concurrent planing approaches may help to achieve timely decision‐making and lasting outcomes for children.
What's Special About Banks?
Authors: Benston George J.
Published: December 2004

I delineate six aspects of how banks have been “special” (although not unique) and then consider whether and to what extent these attributes are still relevant. These include efficiently produced products, importance for the development and growth of economies, international scope, role in economic instability and the conduct of monetary policy, early regulation by governments, and source of data for academic researchers and institutions. Despite changes in the environment and in the ways in which financial services are provided, banks still are special. However, their specialness for public policy concerns is now limited to frauds and deposit insurance. I suggest ways in which these concerns can be dealt with efficiently.
When Are Commercial Loans Secured?
Authors: Gonas John S. , Highfield Michael J. , Mullineaux Donald J.
Published: December 2004

We analyze the factors that influence the decision to secure a commercial loan. We find evidence that variables reflecting adverse selection, moral hazard, and the prospects for default all affect the likelihood a loan will be collateralized. We find no evidence in favor of the predictions of certain theoretical models that high‐quality firms signal by providing collateral. Our results also show that lenders with less risk protection in the form of equity capital are more likely to require collateral, but that banks themselves are less likely to secure loans than nonbanks. Certain loan characteristics also influence the collateralization decision.
Stem cell transplantation for chronic lymphocytic leukaemia
Authors: Paneesha S. , Milligan D. W.
Published: December 2004

Early results of autologous stem cell transplantation (ASCT) in chronic lymphocytic leukaemia (CLL) suggested a significant proportion of patients remained disease‐free for years, raising the possibility of cure. More recent studies have shown no evidence of a plateau in the survival curves indicating that, at best, ASCT may only prolong disease‐free survival. Problems remain over progenitor cell mobilization and one study has raised anxieties about post‐transplant myelodysplasia. The impact of ASCT in CLL will only be properly ascertained in a randomized clinical trial and this in underway in Europe. Initial results of conventional allogeneic transplantation (allo‐SCT) were very disappointing, with an unacceptably high mortality, but did show that cure was possible in some patients. The introduction of reduced intensity conditioning has limited the early transplant‐related mortality but it remains too early to determine what proportion of patients will be cured. In view of these uncertainties, is important that reduced intensity allo‐SCT for CLL is conducted in the context of a clinical trial. Finally, CLL is very heterogeneous condition and great deal more is becoming understood about the prognostic factors. These will become important in allowing patients and their physicians a choice in balancing the risks of various treatment options.
Sensitivity of adult T‐cell leukaemia lymphoma cells to tumour necrosis factor‐related apoptosis‐inducing ligand
Authors: Hasegawa H. , Yamada Y. , Harasawa H. , Tsuji T. , Murata K. , Sugahara K. , Tsuruda K. , Ikeda S. , Imaizumi Y. , Tomonaga M. , Masuda M. , Takasu N. , Kamihira S.
Published: December 2004

Tumour necrosis factor (TNF)‐related apoptosis‐inducing ligand (TRAIL) induces apoptosis in many transformed cells, but not in normal cells, and hence TRAIL has recently emerged as a novel anti‐cancer agent. Adult T‐cell leukaemia lymphoma (ATLL) is a neoplasm of T‐lymphocyte origin aetiologically associated with human T‐lymphotropic virus type 1 (HTLV‐I), and is resistant to standard anti‐cancer therapy. We thus characterized the sensitivity of ATLL cells to TRAIL in this study. Although most primary ATLL cells and cell lines expressed TRAIL death receptors on their surface, they showed only restricted sensitivity to TRAIL. Among the 10 ATLL cell lines examined, one was sensitive, but two had insufficient death‐receptor expression, two had an unknown resistant mechanism with abrogation of the death signal upstream of caspase‐8, and the remaining five showed attenuation of the signal in both extrinsic and intrinsic pathways by X‐linked inhibitor of apoptosis and Bcl‐2/Bcl‐xL respectively. Furthermore, the level of HTLV‐I tax expression was significantly correlated to TRAIL resistance. Interestingly, ATLL cells themselves expressed TRAIL on the cell surface. Constitutive production of TRAIL may offer resistance, thus allowing the development of TRAIL‐resistant ATLL cells. Consequently, the resistant mechanism in ATLL cells against TRAIL was assigned to multiple factors and was not explained by a definitive single agent.
Increased AF1q gene expression in high‐risk myelodysplastic syndrome
Authors: Tse William , Joachim Deeg H. , Stirewalt Derek , Appelbaum Frederick R. , Radich Jerald , Gooley Theodore
Published: December 2004

The AF1q gene is expressed in normal haematopoietic progenitors, but less so in differentiated blood cells. In 47 patients with myelodysplastic syndrome (MDS), AF1q copy numbers were 0–6·8 × 106/μg RNA compared with 1·5–2·4 × 105/μg RNA in normal marrow. AF1q levels correlated with international prognostic scoring system (IPSS) scores (P = 0·004) and the risk of post‐transplant relapse (P = 0·05). Among IPSS high‐risk patients, survival correlated inversely with AF1q levels (P = 0·04). Thus, AF1q levels correlate with high‐risk MDS and may provide a marker for risk stratification.
The influence of Mimulus ringens floral display size on pollinator visitation patterns
Authors: Mitchell R. J. , Karron J. D. , Holmquist K. G. , Bell J. M.
Published: December 2004

Pollinators visiting large floral displays may probe several flowers in sequence, leading to geitonogamous (among‐flower) self‐pollination. To investigate the relationship between floral display size and patterns of pollinator movement, we studied foraging by several pollinator species in four replicate arrays of Mimulus ringens (Scrophulariaceae). In each array displays were trimmed to two, four, eight and 16 flowers per plant.

Bees preferred large displays, and probed more flowers in sequence on large than on small displays. However, the proportion of available flowers probed decreased with display, resulting in nearly equal floral visitation rates across treatments.

Because pollinators probed more flowers in sequence on large displays, plants with numerous flowers should experience more geitonogamous self‐pollination than plants with small displays.

In all four treatments, pollinators frequently visited only one flower before leaving the plant. As the first flower probed on a plant cannot receive geitonogamous pollen, this potentially reduces selfing rates for those flowers, compared to flowers probed late in a long visitation sequence on a plant. Such differences among flowers in pollination history should increase variation in geitonogamous self‐pollination among fruits within plants.

The three most abundant pollinator species differed significantly in behaviours that could influence plant mating patterns, including number of flowers probed per plant; interplant movement distances; and grooming. Variation in foraging patterns was also evident among individuals within species. These subtle differences in response should affect the pollination services provided to plants.
Integrated plant temperature measurement using heat‐sensitive paint and colour image analysis
Authors: Smith W. K. , Brodersen C. R. , Hancock T. E. , Johnson D. M.
Published: December 2004

Despite the fundamental importance of temperature to a variety of physiological processes, such as photosynthesis and transpiration in plants, accurately quantifying and integrating differences in surface temperatures is often difficult, if not impossible.

An inexpensive, user‐friendly technique is now available whereby plants and animals can be air‐brushed with a non‐toxic, heat‐sensitive paint that will generate six or more distinguishable colours across a temperature range of ≈5 °C and a resolution of <1 °C. These temperature‐indicating colours can then be photographed and evaluated quantitatively using image analysis software.

Compared to a more traditional temperature measurement technique (thermocouples), this method resulted in a mean surface temperature of up 5·1 °C warmer than the mean thermocouple temperature, as well as a computed 45% difference in transpirational water loss for a single leaf, multiple leaves on a shoot, and leaves within a crown.
Variation in rate of nectar production depends on floral display size: a pollinator manipulation hypothesis
Authors: Biernaskie J. M. , Cartar R. V.
Published: December 2004

Pollinators typically visit more flowers on plants with larger floral displays, which should present such attractive plants with significant pollen transport losses.

Many‐flowered plants with hermaphrodite flowers might reduce the costs of attractiveness by encouraging fewer sequential flower visits by pollinators. One mechanism that accomplishes this is to produce variable nectar rewards, which will cause risk‐averse foragers to leave the plant after visiting fewer flowers.

We test the prediction that within‐plant variability in nectar production rate increases with the relative number of open flowers on a plant. A field survey of nine herbaceous angiosperm species native to Alberta, Canada revealed a significant positive correlation between nectar variability (measured as standard deviation) and the size of the floral display within species. This relationship existed over and above the null expectation of a positive correlation between mean and SD.

Our results suggest that multiflowered plants might maximize the male fitness returns associated with a plant's attraction status (determined by relative display size), by taking advantage of risk‐averse foraging by their pollinators.
Sub‐basalt decoupled walkaway VSP imaging
Authors: Droujinine Alexander
Published: December 2004

Walkaway vertical seismic profile (VSP) data acquired in basalt‐covered areas can be used to improve knowledge of the sub‐basalt structure. A synthetic example and a case study from the North Atlantic (UK) show that elastic two‐way downward‐continuation migration combined with the stationary‐phase principle is well suited to the processing of VSP data. Vector data are processed using decoupled elastic migration algorithms in both isotropic and anisotropic media. To illustrate the value of decoupled imaging equations, conventional PP imaging is carried out on the enhanced VSP data and compared with the decoupled scheme. Decoupled vector migration operates directly on the displacement vector, and uses various wave modes. Downgoing waves are migrated to image basalt lava flows and measure their anisotropy. Upgoing waves are used for high‐resolution sub‐basalt imaging.
Residual dip moveout in VTI media
Authors: Alkhalifah Tariq , De Hoop Maarten V.
Published: December 2004

Dip‐moveout (DMO) correction is often applied to common‐offset sections of seismic data using a homogeneous isotropic medium assumption, which results in a fast execution. Velocity‐residual DMO is developed to correct for the medium‐treatment limitation of the fast DMO. For reasonable‐sized velocity perturbations, the residual DMO operator is small, and thus is an efficient means of applying a conventional Kirchhoff approach. However, the shape of the residual DMO operator is complicated and may form caustics. We use the Fourier domain for the operator development part of the residual DMO, while performing the convolution with common‐offset data in the space–time domain. Since the application is based on an integral (Kirchhoff) method, this residual DMO preserves all the flexibility features of an integral DMO. An application to synthetic and real data demonstrates effectiveness of the velocity‐residual DMO in data processing and velocity analysis.
Climate change and cereal aphids: the relative effects of increasing CO2 and temperature on aphid population dynamics
Authors: Newman Jonathan A.
Published: December 2004

Experimental evidence regarding the responses of cereal aphids to rising atmospheric CO2 has been ambiguous. Some studies suggest increased population sizes under future CO2 levels, others suggest decreased population sizes, and still others suggest little or no difference. Recently, Newman et al. (2003) constructed a general mathematical model of the aphid–grass interaction to investigate whether or not we should, in fact, expect a general aphid response to rising CO2. They concluded that aphid populations are likely to be larger under future CO2 concentrations if soil N levels are high, the aphid species' nitrogen requirement is low and the aphid species' density‐dependent response in winged morph production is weak. In that model, and in field experiments, CO2 concentration influences aphid population dynamics through the effect it has on plant quality. However, future CO2 concentrations are also likely to be accompanied by higher ambient temperatures, a combination that has received little focus to date. In the present paper, the Newman et al. model is used to consider the combined effects of increased CO2 concentrations and temperature on aphid population sizes. It is concluded that, when both factors are elevated, aphid population dynamics will be more similar to current ambient conditions than expected from the results of experiments studying either factor alone. This result has important implications for future experimentation.
Common birds facing global changes: what makes a species at risk?
Authors: Julliard Romain , Jiguet Frédéric , Couvet Denis
Published: December 2004

Climate change, habitat degradation, and direct exploitation are thought to threaten biodiversity. But what makes some species more sensitive to global change than others? Approaches to this question have relied on comparing the fate of contrasting groups of species. However, if some ecological parameter affects the fate of species faced with global change, species response should vary smoothly along the parameter gradient. Thus, grouping species into few, often two, discrete classes weakens the approach. Using data from the common breeding bird survey in France – a large set of species with much variability with respect to the variables considered – we show that a quantitative measure of habitat specialization and of latitudinal distribution both predict recent 13 year trends of population abundance among 77 terrestrial species: the more northerly distributed and the more specialized a species is, the sharper its decline. On the other hand, neither hunting status, migrating strategy nor body mass predicted population growth rate variation among common bird species. Overall, these results are qualitatively very similar to the equivalent relationships found among the British butterfly populations. This constitutes additional evidence that biodiversity in Western Europe is under the double negative influence of climate change and land use change.
Differential effects of elevated CO2 on acorn density, weight, germination, and predation among three oak species in a scrub‐oak forest
Authors: Stiling Peter , Moon Daniel , Hymus Graham , Drake Bert
Published: December 2004

Much research on the effects of elevated CO2 on forest trees has focused on quantitative changes in photosynthesis, secondary chemistry, and plant biomass. However, plant fitness responses to rising CO2 should also include quantitative measures of reproduction, since most forest systems are recruitment limited. Until now, it has proved very difficult to grow forest trees to sexual maturity in a CO2‐enriched environment. This paper is the first of its kind to address the effects of elevated CO2 on the reproduction of hardwood trees in a natural forest. Beginning in 1996, scrub‐oak vegetation, predominantly three species of scrub‐oaks, Quercus myrtifolia, Q. chapmanii, and Q. geminata, were grown inside eight chambers with elevated CO2 (704 parts per million (ppm)) and eight with ambient CO2 (379 ppm) at Kennedy Space Center, Florida. In elevated CO2, acorn production increased significantly for the dominant species Q. myrtifolia and for Q. chapmanii, but it did not increase for the subdominant, Q. geminata. Acorn weight, germination rate, and predation by weevils were unaffected by CO2. Thus, recruitment of some forest tree species into the Florida scrub‐oak community is likely to be accelerated in an atmosphere of increased CO2. However, because the acceleration of recruitment differs among species, over the long term, Q. myrtifolia and Q. chapmanii will be favored over Q. geminata and this is likely to change patterns of species diversity.
Simulated chronic NO3− deposition reduces soil respiration in northern hardwood forests
Authors: Burton Andrew J. , Pregitzer Kurt S. , Crawford Jeffrey N. , Zogg Gregory P. , Zak Donald R.
Published: December 2004

Chronic N additions to forest ecosystems can enhance soil N availability, potentially leading to reduced C allocation to root systems. This in turn could decrease soil CO2 efflux. We measured soil respiration during the first, fifth, sixth and eighth years of simulated atmospheric NO3− deposition (3 g N m−2 yr−1) to four sugar maple‐dominated northern hardwood forests in Michigan to assess these possibilities. During the first year, soil respiration rates were slightly, but not significantly, higher in the NO3−‐amended plots. In all subsequent measurement years, soil respiration rates from NO3−‐amended soils were significantly depressed. Soil temperature and soil matric potential were measured concurrently with soil respiration and used to develop regression relationships for predicting soil respiration rates. Estimates of growing season and annual soil CO2 efflux made using these relationships indicate that these C fluxes were depressed by 15% in the eighth year of chronic NO3− additions. The decrease in soil respiration was not due to reduced C allocation to roots, as root respiration rates, root biomass, and root turnover were not significantly affected by N additions. Aboveground litter also was unchanged by the 8 years of treatment. Of the remaining potential causes for the decline in soil CO2 efflux, reduced microbial respiration appears to be the most likely possibility. Documented reductions in microbial biomass and the activities of extracellular enzymes used for litter degradation on the NO3−‐amended plots are consistent with this explanation.
Uncertainty analysis of soil organic carbon stock change in Canadian cropland from 1991 to 2001
Authors: VandenBygaart A. J. , Gregorich E. G. , Angers D. A. , Stoklas U. F.
Published: December 2004

National estimates of changes in the amount of soil organic carbon (SOC) in cropland requires an assessment of uncertainty for accounting and reporting under the United Nations Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol. Canada has data sets on SOC stocks in croplands, historical changes in SOC levels due to management practices, and historical changes in the area of land devoted to certain soil management practices. We conducted an analysis of uncertainty of the change in SOC levels due to management practices in Canada from 1991 to 2001 using Monte Carlo analysis and a simple model. Probability distribution functions were determined for each of the inputs of the model, enabling us to assess the uncertainty for the output. The storage rate of SOC in cropland soils of Canada for the 10‐year period ranged from 3.2 to 8.3 Mt C yr−1 at 95% confidence, with a mean of 5.7 Mt C yr−1. Approximately 67% (about 3.8 Mt C yr−1) of the increase in SOC storage in Canada occurred in Saskatchewan where the cropland area under no‐till increased from 10% to 35%, and the area of summer‐fallow declined from 43% to 20% during the study period. The large uncertainty in the effect of no‐till on SOC stock changes in the Gray‐Brown Luvisols of Ontario contributed most to the variance in the model output. If trends in agricultural management continue for the next 10‐year census period, the estimated SOC storage would comprise between 7% and 19% of the gap required to achieve the 6% reduction in 1990 greenhouse gas emission levels for Canada under the Kyoto Protocol.
Intermittent low temperatures constrain spring recovery of photosynthesis in boreal Scots pine forests
Authors: Ensminger Ingo , Sveshnikov Dmitry , Campbell Douglas A. , Funk Christiane , Jansson Stefan , Lloyd Jon , Shibistova Olga , Öquist Gunnar
Published: December 2004

During winter and early spring, evergreen boreal conifers are severely stressed because light energy cannot be used when photosynthesis is pre‐empted by low ambient temperatures. To study photosynthetic performance dynamics in a severe boreal climate, seasonal changes in photosynthetic pigments, chloroplast proteins and photochemical efficiency were studied in a Scots pine forest near Zotino, Central Siberia. In winter, downregulation of photosynthesis involved loss of chlorophylls, a twofold increase in xanthophyll cycle pigments and sustained high levels of the light stress‐induced zeaxanthin pigment. The highest levels of xanthophylls and zeaxanthin did not occur during the coldest winter period, but rather in April when light was increasing, indicating an increased capacity for thermal dissipation of excitation energy at that time. Concomitantly, in early spring the D1 protein of the photosystem II (PSII) reaction centre and the light‐harvesting complex of PSII dropped to their lowest annual levels. In April and May, recovery of PSII activity, chloroplast protein synthesis and rearrangements of pigments were observed as air temperatures increased above 0°C. Nevertheless, severe intermittent low‐temperature episodes during this period not only halted but actually reversed the physiological recovery. During these spring low‐temperature episodes, protective processes involved a complementary function of the PsbS and early light‐induced protein thylakoid proteins. Full recovery of photosynthesis did not occur until the end of May. Our results show that even after winter cold hardening, photosynthetic activity in evergreens responds opportunistically to environmental change throughout the cold season. Therefore, climate change effects potentially improve the sink capacity of boreal forests for atmospheric carbon. However, earlier photosynthesis in spring in response to warmer temperatures is strongly constrained by environmental variation, counteracting the positive effects of an early recovery process.
Groundwater use and salinization with grassland afforestation
Authors: Jobbágy Esteban G. , Jackson Robert B.
Published: December 2004

Vegetation changes, particularly transitions between tree‐ and grass‐dominated states, can alter ecosystem water balances and soluble salt fluxes. Here we outline a general predictive framework for understanding salinization of afforested grasslands based on biophysical, hydrologic, and edaphic factors. We tested this framework in 20 paired grassland and adjacent afforested plots across ten sites in the Argentine Pampas. Rapid salinization of groundwater and soils in afforested plots was associated with increased evapotranspiration and groundwater consumption by trees, with maximum salinization occurring on intermediately textured soils. Afforested plots (10–100 ha in size) showed 4–19‐fold increases in groundwater salinity on silty upland soils but <twofold increases on clay loess soils and sand dunes. Two years of salinity and groundwater measurements at a 40 haEucalyptus camaldulensisplantation revealed that the plantation reduced groundwater recharge, underwent groundwater discharge on >50% of the days, and depressed the water table 38 cm on average compared to the adjacent grassland. Soil cores and vertical electrical soundings indicated that ≈6 kg m−2of salts accumulated close to the water table and suggested that salinization resulted from the exclusion of fresh groundwater solutes by tree roots. Groundwater use with afforestation in the Pampas and in other regions around the world can enhance primary production and provide a tool for flood control. However, our framework and experimental data also suggest that afforestation can compromise the quality of soils and water resources in predictable ways based on water use, climate, and soil texture.
Elevated CO2 alters birch resistance to Lagomorpha herbivores
Authors: Mattson William J. , Kuokkanen Kari , Niemelä Pekka , Julkunen‐Tiitto Riitta , Kellomäki Seppo , Tahvanainen Jorma
Published: December 2004

We studied the three‐way interaction of elevated CO2, nitrogen (N), and temperature (T), and the two‐way interaction of elevated CO2 and early‐season defoliation on the secondary chemistry and resistance of Eurasian silver birch (Betula pendula) and North American paper birch (B. papyrifera) against the Eurasian hare (Lepus timidus) and the North American eastern cottontail rabbit (Sylvilagus floridanus), respectively. Elevated CO2 decreased the palatability of winter‐dormant silver and paper birch stems to both hares and rabbits, respectively. But the effect on hares was only apparent at intermediate levels of N fertilization. Elevated T had no effect on palatability. The effects of elevated CO2, N, and T on levels of silver birch bark phenolics and terpenoids were dominated by two‐way interactions between N and CO2, and N and T. Generally, however, N amendments elicited a parabolic response in carbon partitioning to most biosynthetic classes of silver birch phenolics (i.e. highest concentrations occurring at intermediate N). CO2 elevation was most enhancing at highest levels of N. On the other hand, T increases, more often than not, elicited reductions in phenolics, but especially so at the highest N level. In the case of B. papyrifera, elevated CO2 increased carbon partitioning to Folin‐Denis stem and branch phenolics and condensed tannins. Early‐season defoliation, on the other hand, had no effect on phenolics and tannins but lowered both N and energy levels of branches. Elevated CO2 substantially ameliorated the negative effects of severe defoliation on tree growth. These results support the hypothesis that continuing anthropogenic alterations of the atmosphere may trigger significant changes in plant phenotypic resistance to mammalian herbivores owing to an increasing net carbon balance between the highly vagile supply and demand capacities of plant carbon sources and sinks.
Phytogeography, range size and richness of Australian endemic Sauropus (Euphorbiaceae)
Authors: Hunter John T.
Published: December 2004

Aim  To investigate the distribution of Australian species of Sauropus. The information obtained is used to (1) identify areas of highest richness and centres of endemism, (2) investigate latitudinal gradients of richness and range size, (3) determine the types of rarity shown, and (4) provide hypotheses on historical biogeography of the genus within Australia.

Location  Australia.

Methods  Specimens from 17 herbaria and field searches were examined and label and field information collated on distribution, habit and habitat. Distribution information was used to map all species within 784 grid cells of 1° × 1° and within the 97 Australian ‘ecological regions’. Morphometric cluster analysis of species was conducted using Kulczynski association and flexible UPGMA on 23 character states. Simple regression was used to correlate species richness, density and range size to changes in latitude. CLIMEX is used to match the climate of the region of highest richness in Australia with other areas of the world.

Results  Species richness was highest within the tropical north of Australia, and most species were associated with tropical savanna woodlands. Two areas were identified as centres of endemism and these corresponded closely to areas of high species richness. Four morphological groups were identified. One species (Sauropus trachyspermus) was found to be widespread, however all other species had small geographical ranges. Species richness and range size were significantly correlated with changes in latitude. Ten species were found to be of the rarest type, warranting conservation initiatives.

Main conclusions  Two regions of high richness and endemism of Sauropus occur, Thailand and Australia. Within Australia, the Kakadu‐Alligator River and the Cairns‐Townsville areas were identified as centres of endemism and high species richness for Sauropus. Australian Sauropus in general occur in similar communities and climates as other members of the genus elsewhere. Ten of the 27 species of Australian endemic Sauropus are extremely rare and warrant conservation initiatives. Correlations of latitude to species richness are potentially due to Sauropus radiating from the climatically stable top end of Australia. Increasing range size in more southern latitudes may also be due to stability of climates in the top end or because there is more available land area at these latitudes. Sauropus micranthus, the only non‐endemic species, is probably a more recent invader from the Tertiary period when tropical rain forests where more extensive and congruent with those of New Guinea.
Desert vines: a comparison of Australia with other areas
Authors: Parsons R. F.
Published: December 2004

Aim  To characterize the Australian desert vine flora and to compare it with that of deserts in other continents.

Location  The Stony Deserts, the Simpson Desert and the four main deserts of Western Australia.

Methods  The Western Australian Herbarium data base and published papers were used to develop vine checklists for each Australian desert studied. A literature search was used to classify the families and genera into phytogeographical elements and to provide data for intercontinental comparisons.

Results  Thirty‐seven vine species are listed for the six Australian deserts studied. They constitute from 0.8 to 2.7% of the vascular flora, which is within the normal range for arid zone floras. Comparing Australian data with those from the Sonoran and Chihuahuan deserts (North America), for non‐vine taxa, very different phylogenetic lines are present. However, for vines, three of the four most important families are the same in each case, viz. Convolvulaceae, Fabaceae and Asclepiadaceae. This reflects large pantropical and cosmopolitan families shared between all three data sets. At the generic level, in Australia pantropical taxa and taxa from the Old World tropics far outnumber endemic ones, as do pantropical and neotropical genera in North America. Herbaceous vines predominate in Australian deserts as they do in North American ones, but nevertheless, the percentage of woody vines is higher in Australia (32%) than in North America (highest value of 24%). Earlier views that Australian deserts are rich in annual vines are not supported.

Main conclusions  For many life‐forms, the Australian flora is composed of very different phylogenetic lines to the floras of other continents. However, for desert vines, at the level of family and even of genus, there are surprising similarities between Australia and even a continent as distant as North America, because of shared pantropical and cosmopolitan taxa.