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Source segregation and treatment of urine and faeces from dairy cattlereduces GHG and NH3 emissions in covered storage

Managing dairy excreta as slurry can result in significant emissions of ammonia (NH3) and greenhouse gases (GHGs) during storage and thereafter. Additionally, slurry often has an imbalanced nitrogen (N) to phosphorus (P) ratio for crop fertilization. While various treatments exist to address emissions and nutrient imbalances, each has trade-offs that can result in pollution swapping. An integrated management system, starting with source segregation (SS) in-house to separate faeces and urine into two manageable streams followed by step-wise complementary treatments has been designed to manage nutrients and reduce emissions in the whole chain, but its effect on emissions in storage remains untested. This study investigated NH3, nitrous oxide (N2O), and methane (CH4) emissions and total N losses from integrated storage systems combining SS, mesophilic or thermophilic anaerobic digestion (AD), acidification, drying and zeolite addition and an impermeable cover. These systems were compared to two reference slurry storage systems: in-house uncovered (US) and outside covered (CS). A 30-day lab-scale experiment was conducted at 10 °C, monitoring emissions using an INNOVA1412 gas analyser, while total N losses were assessed using mass balance. Results indicated that the SS fractions treated before covered storage exhibited significantly lower emissions (NH3 or CH4 or both) compared to both reference slurry storage systems (US and CS). Source segregation combined with acidification of urine and AD of faeces at 35 °C and an impermeable cover allowed for a 99% reduction in NH3 emissions, a 45% reduction in CH4 emissions and had no effect on N2O emissions as compared to US. When AD of faeces was conducted at 55 °C instead of 35 °C, the CH4 emission was reduced by 77% compared to US. This study concludes that SS combined with urine and faeces treatment allows a more effective and simultaneous reduction of all emissions in storage as compared to slurry storage systems, while also effectively separating nutrients allowing more precise N and P fertilization with dairy excreta. Further research is necessary to assess emissions and fertilizer value of treated fractions after field application, in addition to the associated costs.

The impact of blockchain on the auditor's audit approach

The current standard in accounting practice is the double-entry approach. Basis of the double-entry approach is that every financial event brings two equal and offsetting entries. Since these financial events are not automatically confirmed by both parties, the accounting quality can be improved. The blockchain mechanism possibly offers a different take on accounting. Based on an experimentation approach, data was collected to compare the double-entry method with the blockchain-based triple-entry method. The results show that the main difference concerns determining the completeness of the financial statement items. In the situation of double-entry accounting, segregation of duties is applied to do so. In the blockchain situation, the underlying mechanism of the blockchain already ensures this.

Tourism as a tool for colonization, and segregation. The case of East Jerusalem, Palestine (Keynote speech)

Tourism as a tool for colonization, displacement and segregation. The case of Occupied East Jerusalem, Palestine

Decision-makers self-servingly navigate the equality-efficiency trade-off of free partner choice in social dilemmas among unequals

Cooperation is more likely upheld when individuals can choose their interaction partner. However, when individuals differ in their endowment or ability to cooperate, free partner choice can lead to segregation and increase inequality. To understand how decision-makers can decrease such inequality, we conducted an incentivized and preregistered experiment in which participants (n=500) differed in their endowment and cooperation productivity. First, we investigated how these individual differences impacted cooperation and inequality under free partner choice in a public goods game. Next, we calculated if and how decision-makers should restrict partner choice if their goal is to decrease inequality. Finally, we studied whether decision-makers actually did decrease inequality when asked to allocate endowment and productivity factors between individuals, and combine individuals into pairs of interaction partners for a two-player public goods game. Our results show that without interventions, free partner choice, indeed, leads to segregation and increases inequality. To mitigate such inequality, decision-makers should curb free partner choice and force individuals who were assigned different endowments and productivities to form pairs with each other. However, this comes at the cost of lower overall cooperation and earnings, showing that the restriction of partner choice results in an equality-efficiency trade-off. Participants who acted as third-parties were actually more likely to prioritize inequality reduction over efficiency maximization, by forcing individuals with unequal endowment and productivity levels to form pairs with each other. However, decision-makers who had a ‘stake in the game’ self-servingly navigated the equality-efficiency trade-off by preferring partner choice interventions that benefited themselves. These preferences were partly explained by norms on public good cooperation and redistribution, and participants’ social preferences. Results reveal potential conflicts on how to govern free partner choice stemming from diverging preferences ‘among unequals’.

Sustainable urban innovation strategies

In recent years, it has become a commonplace to argue that cities should be the focus point of sustainable development. Various authors have presented a variety of arguments why cities should be the preferred target to foster sustainable development-focused innovation; - The average consumption of resources of urban dwellers is higher. - The population of cities is growing continuously, while rural populations stabilize. - Deteriorating living conditions and segregation in cities caused by processes of gentrification of traditional neighbourhoods that drive out lower income groups to the suburbs. - Cities are ‘concentrated’ emitters of pollutants and therefore solutions and re-use might be easier to implement. https://doi.org/10.3390/su11185013 LinkedIn: https://www.linkedin.com/in/karel-mulder-163aa96/