Sources, fate, and toxic hazards of oxygenated polycyclic aromatic hydrocarbons (PAHs) at PAH-contaminated sites

In this paper we show that oxygenated polycyclic aromatic hydrocarbons (oxy-PAHs) are important cocontaminants that should be taken into account during risk assessment and remediation of sites with high levels of PAHs. The presented data, which have been collected both from our own research and the published literature, demonstrate that oxy-PAHs are abundant but neglected contaminants at these sites. The oxy-PAHs show relatively high persistency and because they are formed through transformation of PAHs, their concentrations in the environment may even increase as the sites are remediated by methods that promote PAH degradation. Furthermore, we show that oxy-PAHs are toxic to both humans and the environment, although the toxicity seems to be manifested through other effects than those known to be important for polycyclic aromatic compounds in general, that is, mutagenicity and carcinogenicity. Finally, we present data that support the hypothesis that oxy-PAHs are more mobile in the environment than PAHs, due to their polarity, and thus have a higher tendency to spread from contaminated sites via surface water and groundwater. We believe that oxy-PAHs should be included in monitoring programs at PAH-contaminated sites, even if a number of other toxicologically relevant compounds that may also be present, such as nitro-PAHs and azaarenes, are not monitored. This is because oxy-PAH levels are difficult to predict from the PAH levels, because their environmental behavior differs substantially from that of PAHs, and oxy-PAHs may be formed as PAHs are degraded.     

中国生态保护政策的县域经济效应——来自国家重点生态功能区的证据

为保障生态产品供给，中国设立了限制开发的国家重点生态功能区，建立了生态保护转移支付制度.本文首次在县域层面构建2002~2017年县级面板数据，运用倾向得分匹配法构造政策组的“反事实”情形，基于双重差分法评估重点生态功能区政策的县域经济效应.结果表明，该政策提高了县域财力、长期来看一定程度改善了产业结构；以标准财政缺口为主的资金分配机制弱化了县域经济发展激励，资金补助不能完全抵消限制开发对县域经济带来的负向影响；固定资产投资和内资企业受影响较大.随着投入资金累积、生态产品价值的转化，该负向效应随时间而减弱、经济促增效应逐渐显现.政策效应在不同生态功能和经济区位间表现出明显的异质性.建议持续增加生态转移支付资金、将生态产品供给数量和质量作为资金分配依据，考虑按生态功能类型设计差异化政策，更好激励县域生态产品高水平供给与经济价值实现的双赢，促进区域均衡发展.     

Estimating uncertainties in the life cycle assessment of composting household biowaste and urban green waste in Germany

Life cycle assessment (LCA) of waste treatment processes is often associated with considerable uncertainties. The aim of this study is to estimate the total uncertainty in the modelled composting system and the influence of material and process parameters on the uncertainty. Four composting combinations with fresh (FC) and mature substrate compost (MSC) from partially enclosed (PEC) and open composting (OC) were investigated. Perturbation analysis was used to determine the effect of parameters on the result and Monte Carlo simulation was used to estimate the total uncertainty. This study showed that the production of MSC using PEC had the lowest overall impacts across all impact categories except ozone depletion. Results of the Monte Carlo simulation showed that comparing composting options was challenging. The sensitivity ratios obtained from the perturbation analysis showed that the process parameter percentage of carbon fraction degraded was the most influential for FC. In MSC, the moisture content in the input material and the substitution factor used for peat were the most influential. Monte Carlo simulations demonstrated the overall uncertainty of the model and its relevance when comparing results between combinations. The perturbation analysis identified the parameters that required more accurate data to reduce the uncertainty in the model.

Graphical abstract

     

Pyrolysis of lemon peel waste in a fixed-bed reactor and characterization of innovative pyrolytic products

Journal of Material Cycles and Waste Management - Lemon peel waste (LPW) were pyrolysed in a laboratory fixed-bed reactor at final temperature of 300 °C, 400 °C and...     

Extraction and characterization of chitin,chitosan, and protein hydrolysate from the invasive Pacific blue crab,Portunus segnis (Forskål, 1775) having potential biological activities

Environmental Science and Pollution Research - The diversity of marine biomasses is a set of exploitable and renewable resources with application in several sectors. In this context, a co-culture...     

Exposure to microplastics leads to a defective ovarian function and change in cytoskeleton protein expression in rat

Environmental Science and Pollution Research - Microplastics (MPs) are ubiquitous environmental contaminants; through their physicochemical properties, they can have potentially negative effects on...     

Contribution of warm habitat to cold-water fisheries

A central tenet of landscape ecology is that mobile species depend on complementary habitats, which are insufficient in isolation, but combine to support animals through the full annual cycle. However, incorporating the dynamic needs of mobile species into conservation strategies remains a challenge, particularly in the context of climate adaptation planning. For cold-water fishes, it is widely assumed that maximum temperatures are limiting and that summer data alone can predict refugia and population persistence. We tested these assumptions in populations of redband rainbow trout (Oncorhynchus mykiss newberrii) in an arid basin, where the dominance of hot, hyperproductive water in summer emulates threats of climate change predicted for cold-water fish in other basins. We used telemetry to reveal seasonal patterns of movement and habitat use. Then, we compared contributions of hot and cool water to growth with empirical indicators of diet and condition (gut contents, weight–length ratios, electric phase angle, and stable isotope signatures) and a bioenergetics model. During summer, trout occurred only in cool tributaries or springs (<20 °C) and avoided Upper Klamath Lake (>25 °C). During spring and fall, ≥65% of trout migrated to the lake (5–50 km) to forage. Spring and fall growth (mean [SD] 0.58% per day [0.80%] and 0.34 per day [0.55%], respectively) compensated for a net loss of energy in cool summer refuges (–0.56% per day [0.55%]). In winter, ≥90% of trout returned to tributaries (25–150 km) to spawn. Thus, although perennially cool tributaries supported thermal refuge and spawning, foraging opportunities in the seasonally hot lake ultimately fueled these behaviors. Current approaches to climate adaptation would prioritize the tributaries for conservation but would devalue critical foraging habitat because the lake is unsuitable and unoccupied during summer. Our results empirically demonstrate that warm water can fuel cold-water fisheries and challenge the common practice of identifying refugia based only on summer conditions.     

Motivating children's cooperation to conserve forests

Forests are essential common-pool resources. Understanding children's and adolescents’ motivations for conservation is critical to improving conservation education. In 2 experiments, we investigated 1086 school-aged children and adolescents (6–16 years old) from the United States, China, and the Democratic Republic of Congo. Testing participants in groups, we assessed their motivation for conservation based on collective-risk common-pool goods games in which they were threatened with losing their endowment unless the group donation exceeded a threshold needed to maintain the forest. Extrinsic motivations, rather than intrinsic, tended to lead to successful cooperation to maintain a forest. Certainty of losing individual payoffs significantly boosted successful cooperative conservation efforts across cultures (success rates were 90.63% and 74.19% in the 2 risk-extrinsic conditions, and 43.75% in the control condition). In U.S. participants, 2 extrinsic incentives, priming discussions of the value of forests and delay of payoffs as punishment, also increased success of cooperative conservation (success rates were 97.22% and 76.92% in the 2 extrinsic-incentive conditions, and 29.19% and 30.77% in the 2 control conditions). Conservation simulations, like those we used, may allow educators to encourage forest protection by leading groups to experience successful cooperation and the extrinsic incentives needed to motivate forest conservation.