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AbstractAfter dredged sediments have settled in a temporary upland disposal site, ripening starts, which turns waterlogged sediment into aerated soil. Aerobic biological mineralization of organic matter (OM) and chemical oxidation of reduced sulfur compounds are the major biochemical ripening processes. Quantitative data describing these processes are scarce. Therefore, aerobic oxidation and mineralization of five previously anaerobic dredged sediments were studied during a 160‐d laboratory incubation experiment at 30°C. A double exponential decay model could adequately describe sulfur oxidation and OM mineralization kinetics. During the first 7 d of incubation, 23 to 80% of the total sulfur was oxidized, after which no further sulfur oxidation was observed. Oxygen used for sulfur oxidation amounted up to 95% of the total oxygen uptake in the first 7 d and up to 45% of the oxygen uptake during the entire incubation period. Mineralization rates of the rapidly mineralizable OM fractions that degraded during the first 14 to 28 d of incubation were 102 to 103 times higher than the mineralization rates of the slowly mineralizable OM during the remaining period. First‐order mineralization rates of the slowly mineralizable OM were 0.22 × 10−3 to 0.54 × 10−3 d−1 and can be compared with those of terrestrial soils. Yields of biomass on substrate ranged from 0.08 to 0.45 g Cbiomass/g COM and appeared to be higher for rapidly mineralizing OM than for slowly mineralizing OM. The results of this study can be used to optimize conditions during temporary disposal of sediments, to estimate the potential decrease in OM, and for future studies on the possible link between OM mineralization and degradation of hydrophobic organic contaminants.

New approach proposed for defining preconditions for human development Crossing certain biophysical thresholds could have disastrous consequences for humanity Three of nine interlinked planetary boundaries have already been overstepped

Het idee van een biomassawerf (vorm van grondstoffenbank) sluit goed aan bij de rol en positie die Rova vervult in de afvalverwerkingsketen en het streven naar hoogwaardige recycling. In de regio IJssel Vecht zamelt Rova ca. 33.500 ton gft in, in de overige regio’s ca. 9.500 ton. Andere stromen die Rova op dit moment inzamelt bij gemeenten zijn grof tuinafval, bladafval, snoeihout en bermgras/slootmaaisel. In het rapport wordt ook stilgestaan bij de beschikbaarheid van agrarische residuen in de regio IJssel Vecht. Rova is als publieke dienstverlener actief voor de aangesloten gemeenten. Het bedrijf is een publieke tot semi-publieke organisatie. Dit betekent dat Rova de concurrentie met groenaannemers, fouragehandelaren of handelaren in houtsnippers zal moeten vermijden. De meeste kansen liggen dan ook op het gebied van residuen van landschapsbeheer, zoals takhout, berm- en natuurgras en riet. De volgende product markt combinaties worden als kansrijk geschouwd: Lokale houtsnippers voor lokale energie; Maaisel en loof voor energie en vezels; Riet voor energie en vezels.

Ambitious international targets are being developed to protect and restore biodiversity under the Convention on Biological Diversity's post-2020 Global Biodiversity Framework and the European Union's Green Deal. Yet, the land system consequences of meeting such targets are unclear, as multiple pathways may be able to deliver on the set targets. This paper introduces a novel scenario approach assessing the plural implementations of these targets. The Nature Futures Framework (NFF) developed by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services aims to illustrate the different, positive ways in which society can value nature. It therefore offers a lens through which the spatial implementation of sustainability targets may be envisioned. We used CLUMondo, a spatially explicit model, to simulate plural land system scenarios for Europe for 2050. The model builds on current land system representations of Europe and explores how and where sustainability targets can be implemented under projected population trends and commodity demands. We created three different scenarios in which the sustainability targets are met, each representing an alternative, normative view on nature as represented by the NFF, favoring land systems providing strong climate regulation (Nature for Society), species conservation (Nature for Nature), or agricultural heritage features (Nature as Culture). Our results show that, irrespective of the NFF view, meeting sustainability targets will require European land systems to drastically change, as natural grasslands and forests are forecast to expand while productive areas are projected to undergo a dual intensification and diversification trajectory. Despite each NFF perspective showcasing a similar direction of change, 20% of Europe's land area will differ based on the adopted NFF perspective, with hotspots of disagreement identified in eastern and western Europe. These simulations go beyond existing scenario approaches by not only depicting broad societal developments for Europe, but also by quantifying the land system synergies and trade-offs associated with alternative, archetypal, interpretations and values of how nature may be managed for sustainability. This quantification exemplifies a means towards constructive dialogue, on the one hand by acknowledging areas of contention, and bringing such issues to the fore, and on the other by highlighting points of convergence in a vision for a sustainable Europe.

Setting up strategies for a sound management of plastic packaging waste (PPW) is becoming increasingly crucial at many levels of the value chain in Europe. After the very first implementation of an extended producer responsibility scheme in Germany in 1991, many EU Countries followed. This resulted in a complex network of schemes that differ from one member state to another. This paper brings together the three latest studies describing the current flows of PPW across the waste value chain from Austria (reference year 2013), Germany and the Netherlands (reference year 2017). With this aim, the models of the three single studies have been adapted to fit into a common model, allowing to perform a comparative analysis. Although with a relatively comparable product market, the three countries have different management systems (e.g., separate collection systems, target sorting products and treatment of residual waste), reflecting different national strategies to achieve the circular economy targets. Recycling rates (in terms of washed milled goods at the output of the recycling process) for the three countries resulted in 23%, 43% and 30% of the total mass of PPW generated in, respectively, Austria, Germany and the Netherlands. The fraction of mixed recycled plastics, relevant for Germany and the Netherlands only, was determined to be one of the major determinants of the differences in recycling rates. Furthermore, the discussion revolves around new political targets that have the potential to contribute to addressing the issue of tradeoff between quantity and quality of recycled plastics placed on the market, with measures such as design-for-recycling and eco-modulation of EPR fees playing a critical role, while also pointing out the aspects that inevitably hinder closed-loop recycling.

AbstractSulfate reduction in salt‐rich wastewaters using unadapted granular sludge was investigated in 0.9 L UASB reactors (pH 7.0 ± 0.2; hydraulic retention time from 8–14 h) fed with acetate, propionate, or ethanol at organic loading rates up to 10 gCOD.L−1.day−1 and in excess sulfate (COD/SO of 0.5). High‐rate sulfate reduction rates (up to 3.7 gSO42‐.L−1.day−1) were achieved at salinities exceeding 50 gNaCl.L−1 and 1 gMgCl2.L−1. Sulfate reduction proceeded at a salinity of up to 70 gNaCl.L−1 and 1 gMgCl2.L−1 (corresponding to a conductivity of about 85–90 mS.cm−1), although at lower rates compared to a conductivity of 60–70 mS.cm−1. Ethanol as well as propionate were suitable substrates for sulfate reduction, with acetate and sulfide as the end products. The successful high‐rate treatment was due to the proliferation of a halotolerant incomplete oxidizing SRB population present in the unadapted inoculum sludge. Bioaugmentation of this sludge with the acetate oxidizing halotolerant SRB Desulfobacter halotolerans was unsuccessful, as the strain washed out from the UASB reactor without colonizing the UASB granules. © 2004 Wiley Periodicals, Inc.

The coast of The Netherlands is protected by nourishing sand. Generally, two different techniques are used, beach nourishment and shoreface nourishment. The latter technique supplies sand at a water depth of about 5-8m in the surf zone, and has been used on a regular basis since 1997 with increasing volumes since 2001. Observations on the bivalve mollusc Spisula subtruncata that was abundant before 1997 and a key food species for wintering seaduck show a decline since 2001. This coincided with a decrease in the abundance of the Common Scoter Melanitta nigra, the most numerous wintering seaduck off the Dutch coast. These observations raised concern about shoreface nourishments. This study analyses the timing and locations of shoreface nourishments in combination with S. subtruncata abundance and spatial distribution. Against the expectation, no causal relationship was found between the decline of S. subtruncata and shoreface nourishments. Other causes, such as climate change, fisheries, unsuccessful settlement or predation of spatfall are more likely behind the decline of Spisula along the Dutch coast.