Urbanisation Alters Fatty Acids in Stream Food Webs

Fatty acids are essential to macroinvertebrate growth and reproduction and can indicate food web structure and nutritional quality of basal resources. However, broad‐scale examinations of how catchment land cover and associated stressors affect the proportions of fatty acids (FAs) in stream food webs are few. Here, we: (1) examine relationships among proportions of FAs among benthic periphyton and macroinvertebrate collector/gatherers, shredders, and predators; and (2) test if relationships between periphytic and macroinvertebrate FAs were altered due to the intensity of urban development in catchments. Proportions of the ≥20‐C eicosapentaenoic acid (EPA 20:5ω3), arachidonic acid (ARA 20:4ω6), and docosahexaenoic acid (22:6ω3) indicated collector/gatherers had a diet richer in periphyton than in shredders, which had significantly lower proportions of these FAs. Collector/gatherers were in turn likely to be high‐quality sources of ω3 and ≥ 20‐C FAs for predators, which also had significantly greater EPA and ARA proportions than those in shredders. Linoleic (18:2ω6) and α‐linolenic acid (18:3ω3) comprised the greatest proportions of FAs in shredders, which suggested a diet dominated by leaf litter and associated hyphomycetes. As catchment urbanisation increased, proportions of total ω3 FAs and EPA in periphyton were significantly greater. This pattern also was seen through macroinvertebrate consumers and predators, given that proportions of these FAs in macroinvertebrates also were significantly correlated with factors associated with catchment urbanisation. The significant increase in total ω3 FAs and EPA proportions within shredders indicated that periphyton growth, and their FAs, increased on leaf litter, probably due to greater nutrient concentrations associated with catchment urbanisation. Proportions of total ω6 FAs in biota were not significantly correlated with factors associated with urban development, which could indicate that they were of sufficient abundance for consumers regardless of urban intensity or possible changes in their sources. Our study provides an informative first step that identified notable differences in proportions of FAs among macroinvertebrates in urban streams and an increase in proportions of total ω3 FAs and EPA in periphyton, consumers, and predators as catchment urbanisation increases. Identifying how FA relationships within food webs change in response to catchment alterations and stressors could inform land use and management decisions by linking environmental changes to measures important to ecosystem outcomes

Value added utilization of by-product electric furnace ferronickel slag as construction materials: A review

This paper reviews the potential use of electric furnace ferronickel slag (FNS) as a fine aggregate and binder in Portland cement and geopolymer concretes. It has been reported that the use of FNS as a fine aggregate can improve the strength and durability properties of concrete. Use of some FNS aggregates containing reactive silica may potentially cause alkali-silica reaction (ASR) in Portland cement concrete. However, the inclusion of supplementary cementitious materials (SCM) such as fly ash and blast furnace slag as partial cement replacement can effectively mitigate the ASR expansion. When finely ground FNS is used with cement, it shows pozzolanic reaction, which is similar to that of other common SCMs such as fly ash. Furthermore, 20% FNS powder blended geopolymer showed greater strength and durability properties as compared to 100% fly ash based geopolymers. The utilization of raw FNS in pavement construction is reported as a useful alternative to natural aggregate. Therefore, the use of by-product FNS in the construction industry will be a valuable step to help conservation of natural resources and add sustainability to infrastructures development. This paper presents a comprehensive review of the available results on the effects of FNS in concrete as aggregate and binder, and provides some recommendations for future research in this field

Score a goal for climate: Assessing the carbon footprint of travel patterns of the English Premier League clubs

Football is the most popular sport, globally and in the United Kingdom. However it generates a range of negative environmental impacts, such as climate change, due to an extensive amount of travel involved. The growing contribution of football clubs to the global carbon footprint has been recognised, but never consistently assessed. This study assesses the carbon footprint of the English Premier League (EPL)clubs, using the patterns of their domestic travel in the 2016/2017 season as a proxy for analysis. The study shows that, within the 2016/17 season, the EPL clubs produced circa 1134 tonnes of CO 2- eq. as a result of their travel, where transportation accounts for 61% of the carbon footprint. To reduce this carbon footprint, a careful review of the current corporate travel and procurement practices in the EPL clubs is necessary. This is in order to optimise the travel itineraries, prioritise more climate-benign modes of transport and contract budget accommodation providers with the ‘green’ credentials