Allocation solutions for secondary material production and end of life recovery: Proposals for product policy initiatives

This paper aims at analysing how secondary materials production and end of life recovery processes are modelled in life cycle-based environmental assessment methods in order to discuss their suitability in product policy-support contexts, with a focus on Sustainable Consumption and Production (SCP) policies. The equations prescribed in three published, widely recognised standards are evaluated. In addition, more recent modelling approaches that have been adopted in the context of two EU product policy initiatives (the Product Environmental Footprint (PEF) and the Resource Efficiency Assessment of Products (REAPro)) are similarly analysed. All of the methods are scrutinised against eight criteria which we deem to be important in product policy-support contexts, including comprehensiveness, accommodation of open-loop and closed-loop product systems, and consideration of recyclability/recoverability rates, to name a few. Based on this analysis, it is suggested that the PEF and REAPro modelling approaches appear to be better suited for use in product policy-support contexts than do the currently widely endorsed methods that we considered.     

Irrigation water management policies: Allocation and pricing principles and implementation experience

Food security and sustainable development require efficient use of water resources, especially in irrigation. Economic pricing can be an effective tool to achieve more efficient water use, provided it is supported by other policies in implementation. Applying various water pricing and cost recovery arrangements is suggested for efficient allocation. Any adverse impact on farmers’ incomes must be addressed and more reliable service must accompany higher prices. Experience from several countries suggests a variety of implementation issues. Essential complements to water pricing are water distribution rules and technological choices at critical nodes in the delivery system that allow farmers flexibility in conserving water in response to higher prices. Among supporting institutions, water users associations seem a higher priority than water markets.     

An environmental evaluation of geopolymer based concrete production: reviewing current research trends

In this study we carry out a detailed environmental evaluation of geopolymer concrete production using the Life Cycle Assessment methodology. The literature shows that the production of most standard types of geopolymer concrete has a slightly lower impact on global warming than standard Ordinary Portland Cement (OPC) concrete. Whilst our results confirm this they also show that the production of geopolymer concrete has a higher environmental impact regarding other impact categories than global warming. This is due to the heavy effects of the production of the sodium silicate solution. Geopolymer concrete made from fly ashes or granulated blast furnace slags based require less of the sodium silicate solution in order to be activated. They therefore have a lower environmental impact than geopolymer concrete made from pure metakaolin. However, when the production of fly ashes and granulated blast furnace slags is taken into account during the life cycle assessment (using either an economic or a mass allocation procedure), it appears that geopolymer concrete has a similar impact on global warming than standard concrete. This study highlights that future research and development in the field of geopolymer concrete technology should focus on two potential solutions. First of all the use of industrial waste that is not recyclable within other industries and secondly on the production of geopolymer concrete using a mix of blast furnace slag and activated clays. Furthermore geopolymer concrete production would gain from using waste material with a suitable Si/Al molar ratio in order to minimise the amount of sodium silicate solution used. Finally, by taking into account mix-design technology, which has already been developed for OPC concrete, the amount of binder required to produce a geopolymer concrete could be reduced.     

Incentives and prices in an emissions trading scheme with updating

Emissions trading schemes where allocations are based on updated baseline emissions give firms less incentive to reduce emissions for a given quota (or allowance) price. Nevertheless, according to Böhringer and Lange [On the design of optimal grandfathering schemes for emission allowances, Europ. Econ. Rev. 49 (2005) 2041–2055], such allocation schemes are cost-effective if the system is closed and allocation rules are identical across firms. In this paper, we show that the cost-effective solution may be infeasible if marginal abatement costs grow too fast. Moreover, if a price cap or banking/borrowing is introduced, the abatement profile is no longer the same as in the case with an auction (or lump-sum allocation). In addition, we show that with allocation based on updated emissions, the quota price will always exceed marginal abatement costs, possibly misguiding policy makers and investors about abatement costs. Numerical simulations indicate that the quota price most likely will be several times higher than marginal abatement costs, unless a significant share of allowances is auctioned.     

Dynamics of grass–clover mixtures—An analysis of the response to management with the PROductive GRASsland Simulator (PROGRASS)

A dynamic plot-scale model PROGRASS was developed to simulate the seasonal and inter-annual dynamics of productive, cut grass/clover mixtures in response to management, and specifically to examine the role of root development on grass/clover interactions. The model was parameterized by virtue of data for dry matter yield, leaf area index, root mass, soil mineral N uptake and biological N fixation from a long-term field trial in north-eastern Switzerland. It was tested using 5 years of independent data for yield and clover fraction from a field experiment with two management regimes carried out on the Swiss Central Plateau. The results of transient simulations indicated that under intensive fertilization grass dominance was initiated by preferential allocation of assimilates to the roots. The rapid growth of the grass root system lowered the substrate C:N ratio, favouring carbon allocation to the shoot, which eventually provided competitive advantages with respect to light interception. Under extensive management, limited N acquisition capacity of the grass root system maintained preferential allocation to the roots, limiting shoot development in the grass and leading to clover dominance. Co-existence regimes with dominance by one of the components were also found in equilibrium experiments, with a transition regime from clover to grass dominance for annual N applications in the range 100–200 kg N ha⁻¹ y⁻¹ that reflected adjustments of the root system to fertilization. It is concluded that the dynamics of grass/clover mixtures is driven by negative and positive feedbacks in the soil–plant system that are strongly controlled by root development and therefore by the allocation patterns of the grass component.     

水资源持续利用的价值评价与配置问题

综述了水资源价值评价与配置的基本问题。水价值阐释了四方面内容 :( 1 )权属 ,( 2 )评价者 ,( 3)多元性及相应的评价方法 ,( 4 )地域性。就三方面分析了水配置 :( 1 )制度配置 ,( 2 )市场配置 ,( 3)保障基本需求。并就水资源持续利用提出了一些建议。     

Total Organic Carbon,an Important Tool in an Holistic Approach to Hydrocarbon Source Fingerprinting

The identification and allocation of multiple hydrocarbon sources in marine sediments is best achieved using an holistic approach. Total organic carbon (TOC) is one important tool that can constrain the contributions of specific sources and rule out incorrect source allocations in cases where inputs are dominated by fossil organic carbon. In a study of the benthic sediments from Prince William Sound (PWS) and the Gulf of Alaska (GOA), we find excellent agreement between measured TOC and TOC calculated from hydrocarbon fingerprint matches of polycyclic aromatic hydrocarbons (PAH) and chemical biomarkers. Confirmation by two such independent source indicators (TOC and fingerprint matches) provides evidence that source allocations determined by the fingerprint matches are robust and that the major TOC sources have been correctly identified. Fingerprint matches quantify the hydrocarbon contributions of various sources to the benthic sediments and the degree of hydrocarbon winnowing by waves and currents. TOC contents are then calculated using source allocation results from fingerprint matches and the TOCs of contributing sources. Comparisons of the actual sediment TOC values and those calculated from source allocation support our earlier published findings (Boehm et al ., 2001) that the natural petrogenic hydrocarbon background in sediments in this area comes from eroding Tertiary shales and associated oil seeps along the northern GOA coast and exclude thermally mature area coals from being important contributors to the PWS background due to their high TOC content.     

A method to assess the allocation suitability of recreational activities: An economic approach

Most existing methods of planning focus on development of a recreational area; less consideration is placed on the allocation of recreational activities within a recreational area. Most existing research emphasizes the economic benefits of developing a recreational area; few authors assessed the allocation suitability of recreational activities from an economic point of view. The purpose of this work was to develop a model to assess the allocation suitability of recreational activities according to the application of a concept of analysis of cost and benefit under a premise of ecological concern. The model was verified with a case study of Taiwan. We suggest that the proposed model should form a critical part of recreational planning.     

Cities vs. agriculture: A review of intersectoral water re-allocation

Water demand management, or making better use of the water we have — as opposed to augmenting supply — is increasingly proposed as a way of mitigating water-scarcity problems. Moving water away from agriculture to uses with higher economic value is one of the main measures widely seen as desirable. Sectoral "allocation stress" is seen as resulting from the disproportionate share, and inefficient use of water in the agricultural sector. This apparent misallocation is often attributed to the failure of government to allocate water rationally.
This paper revisits this commonly-accepted wisdom and examines the nature of urban water scarcity, showing the importance of economic and political factors, shaped by incentives to decision-makers, and sometimes compounded by climatic conditions. It shows that cities' growth is not generally constrained by competition with agriculture. In general, rather than using a narrow financial criterion, cities select options that go along the "path of least resistance," whereby economic, social and political costs are considered in conjunction. The question of allocation stress is thus reframed into an inquiry of how transfers effectively occur and can be made more effective.     

基于数据挖掘的化工生产事故致因主题抽取

为充分挖掘化工生产事故数据中的有效信息和潜在规律,提高对化工事故认知水平,针对某化工集团2010—2016年共1 578起事故数据,利用社会网络分析等方法揭示事故要素间的关联关系;运用潜在狄利克雷分配（LDA）模型进行事故聚类,并抽取到5个事故致因主题。研究结果表明:LDA主题模型等数据挖掘技术能有效挖掘大量事故数据中的潜在信息;5个事故致因主题中,4个涉及到人因或组织层面的缺陷;员工注意力不集中和现场风险管理不足这2个致因主题间具有较强相关性;员工注意力不集中、现场风险管理不足以及设备问题是导致事故发生的主要原因。