Length-mass allometries in amphibians

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"It Takes Two To Tango", A Research About The Risks And Control Measures For The Management Of A Performance Contract For Regular Maintenance Of Rail Infrastructure.

A research about the risks and the administrative measures during the management of a performance contract for the regular maintenance of rail infrastructure. In the sector of rail infrastructure output-contracts, in which the contractor is judged on achieved performances, are getting more in use. The assumption is that this will lead to a more efficient and innovative execution of the maintenance, because the parties involved in the contract have less contact and thus need to take more responsibilities for their proper tasks. Unknown however is how to manage such a contract: What are the risks a contracting partner is confronted with during the term of the contract and how could these risks be managed? This article will discuss a method that will provide answers to these questions. The method consists of a matrix of the possible risks and control measures that the management level of both the sourcing partner and the contractor should discuss. These are cooperation risks and not the safety and availability risks. Within HTM, the bus and tram company of The Hague, this method is used to give direction for a new maintenance contract. It was concluded that management based on performances not always means that contracting partner and contractor have less contact but that it resulted in another behavior and cooperation both for the contracting partner as the contracting party.Institute of Transport and Logistics Studies. Faculty of Economics and Business. The University of Sydne

"Never Regard Yourself As Already So Thoroughly Informed": The Withdrawal of its Invitation to Rodney Syme to Address its 2015 Congress by the Royal Australasian College of Physicians

In 1628, William Harvey presented his revolutionary theory of the circulation to ears at the Royal College of Physicians that had been deafened by the unquestionable authority of Galen’s teachings, from one and a half millennia in the past. Harvey’s theory was initially rejected, despite his faith in his colleagues being eager for truth and knowledge, and never regarding themselves as so well informed that they would not welcome “further information”. Recently Rodney Syme, the retired Melbourne urologist who for a long time has agitated for the legalisation of assisted dying, and also challenged the authorities to apply the current law in response to his admitted assistance to a number of individuals, was invited to address the 2015 Congress of the Royal Australasian College of Physicians. At the eleventh hour, the invitation to speak was withdrawn. In this column, we trace the course of events leading to this withdrawal of the invitation, and describe some of the correspondence to and from the College in response to the withdrawal. We draw parallels between the experiences of Harvey and Syme, and point to lessons to be learnt from the recent episode of apparent unwillingness, on the part of an institution that seeks to present itself as outward-looking, progressive and socially aware, to fulfil this promise in the increasingly important area of the end-of-life

FutureStreams, a global dataset of future streamflow and water temperature

There is growing evidence that climate change impacts ecosystems and socio-economic activities in freshwater environments. Consistent global data of projected streamflow and water temperature are key to global impact assessments, but such a dataset is currently lacking. Here we present FutureStreams, the first global dataset of projected future streamflow and water temperature for multiple climate scenarios (up to 2099) gridded at a 5 arcminute spatial resolution (similar to 10 km at the equator), including recent past data (1976-2005) for comparison. We generated the data using global hydrological and water temperature models (PCR-GLOBWB, DynWat) forced with climate data from five general circulation models. We included four representative concentration pathways to cover multiple future greenhouse gas emission trajectories and associated changes in climate. Our dataset includes weekly streamflow and water temperature for each year as well as a set of derived indicators that are particularly relevant from an ecological perspective. FutureStreams provides a crucial starting point for large-scale assessments of the implications of changes in streamflow and water temperature for society and freshwater ecosystems.Industrial Ecolog

Global implications of crop-based bioenergy with carbon capture and storage for terrestrial vertebrate biodiversity

Bioenergy with carbon capture and storage (BECCS) based on purpose-grown lignocellulosic crops can provide negative CO 2 emissions to mitigate climate change, but its land requirements present a threat to biodiversity. Here, we analyse the implications of crop-based BECCS for global terrestrial vertebrate species richness, considering both the land-use change (LUC) required for BECCS and the climate change prevented by BECCS. LUC impacts are determined using global-equivalent, species–area relationship-based loss factors. We find that sequestering 0.5–5 Gtonne of CO 2 per year with lignocellulosic crop-based BECCS would require hundreds of Mha of land, and commit tens of terrestrial vertebrate species to extinction. Species loss per unit of negative emissions decreases with: (i) longer lifetimes of BECCS systems, (ii) less overall deployment of crop-based BECCS and (iii) optimal land allocation, that is prioritizing locations with the lowest species loss per negative emission potential, rather than minimizing overall land use or prioritizing locations with the lowest biodiversity. The consequences of prevented climate change for biodiversity are based on existing climate response relationships. Our tentative comparison shows that for crop-based BECCS considered over 30 years, LUC impacts on vertebrate species richness may outweigh the positive effects of prevented climate change. Conversely, for BECCS considered over 80 years, the positive effects of climate change mitigation on biodiversity may outweigh the negative effects of LUC. However, both effects and their interaction are highly uncertain and require further understanding, along with the analysis of additional species groups and biodiversity metrics. We conclude that factoring in biodiversity means lignocellulosic crop-based BECCS should be used early to achieve the required mitigation over longer time periods, on optimal biomass cultivation locations, and most importantly, as little as possible where conversion of natural land is involved, looking instead to sustainably grown or residual biomass-based feedstocks and alternative strategies for carbon dioxide removal

What are sources of carbon lock-in in energy-intensive industry? A case study into Dutch chemicals production

Keeping global mean temperature rise well below 2 °C requires deep emission reductions in all industrial sectors, but several barriers inhibit such transitions. A special type of barrier is carbon lock-in, defined as a process whereby various forms of increasing returns to adoption inhibit innovation and the competitiveness of low-carbon alternatives, resulting in further path dependency. Here, we explore potential carbon lock-in in the Dutch chemical industry via semi-structured interviews with eleven key actors. We find that carbon lock-in may be the result of (i) technological incompatibility between deep emission reduction options over time, (ii) system integration in chemical clusters, (iii) increasing sunk costs as firms continue to invest in incremental improvements in incumbent installations, (iv) governmental policy inconsistency between targets for energy efficiency and deep emission reductions, and (v) existing safety routines and standards. We also identify barriers that do not have the self-reinforcing character of lock-in, but do inhibit deep emission reductions. Examples include high operating costs of low-carbon options and low risk acceptance by capital providers and shareholders. Rooted in the Dutch policy setting, we discuss policy responses for avoiding carbon lock-in and overcoming barriers based on the interviews, such as transition plans for individual industries and infrastructure subsidies

Biomass residues as twenty-first century bioenergy feedstock—a comparison of eight integrated assessment models

In the twenty-first century, modern bioenergy could become one of the largest sources of energy, partially replacing fossil fuels and contributing to climate change mitigation. Agricultural and forestry biomass residues form an inexpensive bioenergy feedstock with low greenhouse gas (GHG) emissions, if harvested sustainably. We analysed quantities of biomass residues supplied for energy and their sensitivities in harmonised bioenergy demand scenarios across eight integrated assessment models (IAMs) and compared them with literature-estimated residue availability. IAM results vary substantially, at both global and regional scales, but suggest that residues could meet 7–50% of bioenergy demand towards 2050, and 2–30% towards 2100, in a scenario with 300 EJ/year of exogenous bioenergy demand towards 2100. When considering mean literature-estimated availability, residues could provide around 55 EJ/year by 2050. Inter-model differences primarily arise from model structure, assumptions, and the representation of agriculture and forestry. Despite these differences, drivers of residues supplied and underlying cost dynamics are largely similar across models. Higher bioenergy demand or biomass prices increase the quantity of residues supplied for energy, though their effects level off as residues become depleted. GHG emission pricing and land protection can increase the costs of using land for lignocellulosic bioenergy crop cultivation, which increases residue use at the expense of lignocellulosic bioenergy crops. In most IAMs and scenarios, supplied residues in 2050 are within literature-estimated residue availability, but outliers and sustainability concerns warrant further exploration. We conclude that residues can cost-competitively play an important role in the twenty-first century bioenergy supply, though uncertainties remain concerning (regional) forestry and agricultural production and resulting residue supply potentials

The challenges of applying planetary boundaries as a basis for strategic decision-making in companies with global supply chains

The Planetary Boundaries (PB) framework represents a significant advance in specifying the ecological constraints on human development. However, to enable decision-makers in business and public policy to respect these constraints in strategic planning, the PB framework needs to be developed to generate practical tools. With this objective in mind, we analyse the recent literature and highlight three major scientific and technical challenges in operationalizing the PB approach in decision-making: first, identification of thresholds or boundaries with associated metrics for different geographical scales; second, the need to frame approaches to allocate fair shares in the 'safe operating space' bounded by the PBs across the value chain and; third, the need for international bodies to co-ordinate the implementation of the measures needed to respect the Planetary Boundaries. For the first two of these challenges, we consider how they might be addressed for four PBs: climate change, freshwater use, biosphere integrity and chemical pollution and other novel entities. Four key opportunities are identified: (1) development of a common system of metrics that can be applied consistently at and across different scales; (2) setting 'distance from boundary' measures that can be applied at different scales; (3) development of global, preferably open-source, databases and models; and (4) advancing understanding of the interactions between the different PBs. Addressing the scientific and technical challenges in operationalizing the planetary boundaries needs be complemented with progress in addressing the equity and ethical issues in allocating the safe operating space between companies and sectors