Fruit fate,frugivory, and fruit characteristics: a study of the hawthorn,Crataegus monogyna (Rosaceae)

Summary The fate of fruits from a population of European hawthorn (Crataegus monogyna) in western Oregon, USA, was examined over a two-year period. Only one frugivore, the American robin (Turdus migratorius) foraged on the C. monogyna fruits, making this an unusually straightforward fruit-frugivore system. Dispersal efficiency was low, with an average 21% of seeds being dispersed (carried away from parent plants) each year; the most common fate of fruits was to simply fall. Robins dropped 20% of the fruits that they picked, and defecated/regurgitated 40% of the fruits (seeds) that they swallowed, beneath parent plants. One trait, gruit abundance, strongly affected the probability of bush visitation by robins, bushes with larger fruit displays being preferred. Both absolute dispersal success (number of seeds) and dispersal efficiency (proportion of seeds; success per propagule) were also found to be correlated most strongly with initial fruit abundance. Individual plant fecundity and fruit quality were found to vary little between years; as a result, dispersal efficiencies for individual plants were also annully consistent. Larger (older) plants produced more fruits and therefore had higher fitness. These results suggest that the optimal fruiting strategy for C. monogyna is therefore to get as big as possible as quickly as possible by delaying fruiting until later in life.     

Copper removal from an industrial waste by bioleaching

Summary Copper contained in a solid industrial waste produced in a silicone manufacturing process was leached with spent iron medium from aThiobacillus ferrooxidans culture. Most effective leaching was observed in a continuously fed, dual reactor system. Spent iron medium was generated by growingT. ferrooxidans in 0.9 K iron medium at pH 1.5 in the first reactor, and was transferred to a second reactor in which it leached the copper from the waste. Leaching was effective at a pulp density of the waste material as high as 20%. In experiments run at a pulp density of 2.5%, the spent iron medium was most efficient in leaching copper when it was first diluted 100-fold with a mineral salts solution at pH 1.5. Removal of the copper from the waste appeared to involve its displacement by acid, dissolved mineral salts, and ferric iron. Potentials for practical application of this process are discussed.     

Effects of acid wastes from titanium dioxide production on biomass and species richness of benthic algae

Titanium dioxide wastes are suspected to be toxic to rocky shore communities in an estuary in southeast Norway. An experimental project lasting two years examined whether titanium dioxide wastes affected recolonization by rocky shore organisms. The experiments were performed in situ in six tanks (each with 9 m³ brackish water) at two different levels of salinity. Three different concentrations of industrial waste water were used. The growth season in 1986 was dry and sunny compared to 1987, causing reduction of growth on exposed granite chips compared to controls. At the two highest waste concentrations in the tanks, Fucus serratus was observed with necrotic tissue both years, and in 1986 benthic diatoms were scarce.     

Chemical composition of fresh and composted urban waste

Chemical, spectroscopic (IR and NMR), and molecular characteristics of humus extracted from urban waste before and after compositing are reported. The main differences are in the contents of acidic groups and straight aliphatic chains which diminish in the composted material. In comparing humus characteristics of composted urban waste and soils, the only real difference was found in the elution curves on Sephadex G-100, where the ratio of 100,000 and 1,300 peaks was higher in the compost than in the soil curve. The finding suggests that this ratio is a parameter that could enable us, even if in a semiquantitative manner, to follow the humification process of the compost when its addition to the soil is not less than the autochthonous organic matter content.Research work supported by CNR, Italy, Special grant I.P.R.A.-Sub-project 1. Paper N. 1531.     

中欧组织间合作研究项目MIX-UP助力实现“碳中和”

随着全球塑料循环体系的变革升级,提高塑料的回收利用不仅可以减少塑料在生命周期中的碳排放,还可以解决废塑料潜在的生态环境危害。文中介绍了2019年国家自然科学基金组织间国际 (地区) 合作研究项目“废塑料资源高效生物降解转化的关键科学问题与技术 (MIXed plastics biodegradation and UPcycling using microbial communities,MIX-UP)”。该项目聚焦“塑料污染”这一全球化的问题,围绕中欧双方确定的“塑料生物降解菌群”研究领域,联合中欧双方14家优势科研单位,开展实质性的重大前沿合作研究。针对废塑料生物降解中存在的解聚与重塑两个难题,项目以难降解石油基塑料 (PP、PE、PUR、PET和PS) 以及生物可降解塑料 (PLA和PHA) 的混合废塑料作为研究对象,从塑料微生物降解途径解析及关键元件的挖掘与改造、塑料高效降解混菌/多酶体系的构建与功能调控、塑料降解物的高值化炼制途径设计与利用策略3个方面展开研究。本项目将突破废塑料生物降解转化中高效降解元件挖掘、塑料降解物高值化利用的关键科学问题与技术,探索一条废塑料资源化、高值化、循环化、低碳化的新塑料循环路线,建立以“降塑再造”为核心理念的废塑料生物炼制体系,丰富我国固废资源化生物技术利用平台。项目的实施不仅有助于提升我国塑料 (生物) 循环经济的理论基础和关键技术水平,还可以推动我国与国际科研院所的多边交流与合作,促进我国在生物技术领域的创新发展,助力我国碳中和目标的实现。     

Extended Producer Responsibility in the United States

Extended producer responsibility (EPR) is a policy approach that requires manufacturers to finance the costs of recycling or safely disposing of products consumers no longer want. This article describes the evolution of EPR policies in the United States, focusing on the role of states as policy actors. For their part, federal lawmakers have not embraced EPR policies except to remove some barriers to state‐level initiatives. In the two‐decade period from 1991 to 2011, U.S. states enacted more than 70 EPR laws. In addition, manufacturers have implemented voluntary programs to collect and recycle products, but those efforts have proven largely ineffective in capturing significant quantities of waste products. With the help of new coalitions of diverse interest groups, recently states have renewed efforts to establish effective EPR programs, enacting 40 laws in the period 2008–2011. Several state initiatives suggest a more promising future for EPR.     

Implementing Extended Producer Responsibility Legislation

The goal of this article is to contribute to the understanding of how the multiple, and sometimes conflicting, stakeholder perspectives and prevailing conditions (economic, geographic, etc.) in the implementation locality shape extended producer responsibility (EPR) “on the ground.” We provide an in‐depth examination of the implementation dimension of EPR in a specific case study by examining concrete activities at the operational front of the collection and recycling system, and probing the varying stakeholder preferences that have driven a specific system to its status quo. To this end, we conduct a detailed case study of the Washington State EPR implementation for electronic waste. We provide an overview of various stakeholder perspectives and their implications for the attainment of EPR policy objectives in practice. These findings shed light on the intrinsic complexity of EPR implementation. We conclude with recommendations on how to achieve effective and efficient EPR implementation, including improving design incentives, incorporating reuse and refurbishing, expanding product scope, managing downstream material flows, and promoting operational efficiency via fair cost allocation design.     

Business‐to‐Business Information Technology User Practices at End of Life in the United Kingdom,Germany, and France

Business‐to‐business (B2B) electronics account for a significant volume of the electrical and electronic equipment (EEE) put on the market. Very little B2B waste electrical and electronic equipment (WEEE) is reported as collected in the European Union (EU) in compliance with the WEEE Directive, which uses the policy principle of extended producer responsibility (EPR) to ensure that WEEE is managed correctly. This presents a barrier to parties looking for access to the waste. Company practice dictates the channels into which B2B WEEE flows following primary use. This article presents a study that engaged with company actors directly to get a better understanding of business information technology (IT) EEE asset management. Data were collected to determine the barriers current practice could present to the collection of B2B IT EEE at end of life and the implications of these for the development of policies and strategies for EPR. A questionnaire was developed and data were gathered from organizations in three EU countries—the United Kingdom, Germany, and France—stratified by size. Some notable findings were that there are several routes by which end‐of‐life B2B WEEE can flow. The recycling and refurbishment of B2B IT units at end of use was shown to be commonplace, but it is likely that these units enter streams where they are not reported. The actors disposing of their units did not have information on the management or disposition of these streams. It is concluded that to achieve the goals of EPR for B2B IT WEEE, the networks and the operational practices of these streams need to be better understood when developing strategies and policies.     

Linking Material Flow Analysis with Environmental Impact Potential

Technology transition can have significant implications on the evolution of environmental impact potential of disposed electronics over time. Considering technology transition, we quantify the temporal behavior of ecological and human health impact potential from select heavy metals in electronic waste (e‐waste). The case study analyzes product substitution effects in two electronic cohorts from the U.S. market: (1) computers (laptops substituting for desktops) and (2) televisions (flat‐panel liquid crystal displays [LCDs] and plasma displays substituting for cathode‐ray tubes [CRTs]). Quantities of end‐of‐life (EoL) units to year 2030 are forecasted by the unique combination of dynamic material flow analysis, logistic trend analysis, and product lifespan calibration methods. Metal content from EoL units are assessed via a pathway and effect model using USETox? characterization factors to determine the toxicity potential attributed to heavy metal releases into different media (e.g., air, water, and soil) as an indicator of environmental burden. Results show high impact materials such as lead, nickel, and zinc cause changes in human health toxicity potential and copper causes changes in ecological toxicity potential. Effects of dematerialization, such as reduced metal content in laptops over desktops, provide some positive benefits in toxicity potential per product. However, from a market perspective, emerging e‐waste quantities created by increasing per capita penetration rates of electronics and increasing population will offset gains in environmental performance at the product level. The resulting analysis provides guidance on the timing expected for emerging EoL units and an indication of high impact potential materials requiring pollution prevention as product substitution occurs.     

From Legal Transplants to Sustainable Transition

Extended producer responsibility (EPR), which assigns significant responsibility to producers to take back their end‐of‐life products to create incentives for redesign of products with lower life cycle environmental impacts, has come to a crossroad facing a trade‐off between the original innovation‐oriented regime design and the cost‐efficiency challenges in practice. This is particularly true in its implementation in non‐Organization for Economic Co‐operation and Development (OECD) countries as they are trying to transplant the “best practices” from OECD countries, for there is increasing skepticism as to whether EPR is suitable for developing countries at all. As an important producer of electronic products and destination of electronic waste (e‐waste) flows in the world, China has been expected to play a vital role in the evolution of global governance based on the idea of EPR, either to create new ways for producers to perform their end‐of‐life strategies, or to reshape the mode of production and consumption with its fast‐growing market. However, the establishment of EPR in China has been long and full of difficulties. This article reviews the status and trends in the establishment of an EPR system for waste electrical and electronic equipment (WEEE) management in China. We use the framework of a multilevel perspective of transition theory in our analysis to characterize the complex interactions among various agents in the evolution of the Chinese system from initial innovation‐oriented design to the current efficiency‐oriented version. An ongoing research framework for evaluation of the EPR program in China is outlined as the research agenda in coming years.