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This paper presents a pragmatic framework to inform stakeholders about the sustainability of canteen meals. The framework consists of four parts: (1) an ecological scoring system, based on life cycle assessment results, to score the ecological impact of meals or their components, from which the customer can select to compose a meal; (2) a nutritional scoring of meals based on meeting nutritional criteria; (3) a scoring system to assess the efforts undertaken by the canteen suppliers with regard to sustainable production and management and (4) collected information on relevant topics in food sustainability not covered in previous parts. The framework has furthermore been customized for and applied to the canteen of Ghent University. In light of part 1, several methods to characterize the environmental impact of food products were benchmarked, pinpointing the ecological footprint, the amount of land needed for production and to sequester CO 2 , as most appropriate one. Moreover, the ecological footprint of harvested fish was newly characterized as amount of land indirectly needed for their growth in nature. This highlighted the much lower (2–15 times) ecological footprint of aquaculture than caught fish products, according to this method. The ecological scoring system was consequently based on the ecological footprint but also the carbon footprint due to its relevance, covering the discrepancy between meat, with relatively higher carbon footprint, and caught fish products, with relatively higher ecological footprint. Besides a promotion of more sustainable meals, following guidelines and conclusions were derived: (1) the ecological impact depends on more than just the main component, e.g. frying oil contributes the most to the ecological footprint of fries, and type of food, e.g. a portion ‘pangasius orientale’ (fish), has an about 30% lower ecological footprint than a portion ‘ratatouille vegetables’ (vegetarian); (2) lower salt content, which can mount up to >80% for a meal, to improve nutritional value and (3) provide a variety of portion sizes because nutritional demand varies. Although further improvement is needed, the framework is prominent because of the better characterization of environmental impact, its pragmatic coverage of various sustainability aspects through its four parts, feedback to all stakeholders and its easiness of application for a manifold of meals. [ABSTRACT FROM AUTHOR]

The main goal of a sustainability assessment is to evaluate the impact of systems (e.g., human or natural ones) on areas sought to be protected and maintained over time (e.g., human well-being, ecosystems, etc.). These are called areas of protection (AoPs). Life cycle sustainability assessment is a type of sustainability assessment that focuses on the impact of industrial production systems on AoPs. To further this field, three conceptual challenges should be tackled: (1) framing which areas should primarily be sustained and hence on which the impact should be assessed, that is, (re)defining of the AoPs; (2) accounting for the interconnectedness among AoPs (e.g., influence of ecosystems on human well-being); and (3) the assessment of both benefit and damage to the AoPs (e.g., benefit of industrial products and damage of their production). The aim of this study is to provide a first roadmap to address these three issues and to suggest potential solutions. Regarding the first issue, our conclusion is that human well-being, encompassing health and happiness, is the primary AoP. This is based on the argument that the sustainability concept is inherently anthropocentric. In this regard, other entities such as ecosystems as a whole are sustained in light of human well-being. The well-being adjusted life years, interpreted as years of perfect well-being, is pinpointed as the most promising holistic indicator. To conduct a respective sustainability assessment that tackles the remaining two issues-integrated system modeling of the earth and its support to well-being-is argued as the most suitable approach. [ABSTRACT FROM AUTHOR]

As economies in the European Union are ultimately driven by the final consumption of citizens, policy makers need proper indicators to monitor the environmental impacts associated with this consumption. These indicators can be constructed using two different approaches, each having their strengths and limitations. The top-down approach is based on environmentally extended input–output analysis and quantifies the environmental impacts of product groups and services provided by industrial sectors. The bottom-up approach is based on Life Cycle Assessment and quantifies the environmental impacts of a selection of representative products. The bottom-up approach has already been used by the European Commission's Joint Research Centre to calculate the impacts of the final consumption per capita in the European Union in 2006. In this paper, we calculated these impacts through a top-down approach, using the Exiobase database. The covered household activities are food, consumer goods, mobility, shelter and services. The goal was to calculate all the impact categories recommended by the International Reference Life Cycle Data handbook, and compare both approaches. However, the categories ionizing radiation, toxicity and abiotic resource depletion could not be included, as some relevant emissions and resources are not available in Exiobase. To study more profoundly the impact on natural resources, we added the Cumulative Exergy Extraction From the Natural Environment to the impact assessment. When comparing both approaches, it can be concluded that there is a considerable shift in the results. This means that the information obtained by a top-down approach could supplement the information base for policy support. [ABSTRACT FROM AUTHOR]

For a sustainable future, we must sustainably manage not only the human/industrial system but also ecosystems. To achieve the latter goal, we need to predict the responses of ecosystems and their provided services to management practices under changing environmental conditions via ecosystem models and use tools to compare the estimated provided services between the different scenarios. However, scientific articles have covered a limited amount of estimated ecosystem services and have used tools to aggregate services that contain a significant amount of subjective aspects and that represent the final result in a non-tangible unit such as ‘points’. To resolve these matters, this study quantifies the environmental impact (on human health, natural systems and natural resources) in physical units and uses an ecosystem service valuation based on monetary values (including ecosystem disservices with associated negative monetary values). More specifically, the paper also focuses on the assessment of ecosystem services related to pollutant removal/generation flows, accounting for the inflow of eutrophying nitrogen (N) when assessing the effect of N leached to groundwater. Regarding water use/provisioning, evapotranspiration is alternatively considered a disservice because it implies a loss of (potential) groundwater. These approaches and improvements, relevant to all ecosystems, are demonstrated using a Scots pine stand from 2010 to 2089 for a combination of three environmental change and three management scenarios. The environmental change scenarios considered interannual climate variability trends and included alterations in temperature, precipitation, nitrogen deposition, wind speed, Particulate matter (PM) concentration and CO 2 concentration. The addressed flows/ecosystem services, including disservices, are as follows: particulate matter removal, freshwater loss, CO 2 sequestration, wood production, NO x emissions, NH 3 uptake and nitrogen pollution/removal. The monetary ecosystem service valuation yields a total average estimate of 361–1242 euro ha −1 yr −1 . PM 2.5 (<2.5 μm) removal is the key service, with a projected value of 622–1172 euro ha −1 yr −1 . Concerning environmental impact assessment, with net CO 2 uptake being the most relevant contributing flow, a loss prevention of 0.014–0.029 healthy life years ha −1 yr −1 is calculated for the respective flows. Both assessment methods favor the use of the least intensive management scenario due to its resulting higher CO 2 sequestration and PM removal, which are the most important services of the considered ones. [ABSTRACT FROM AUTHOR]

Terrestrial land and its resources are finite, though, for economic and socio-cultural needs of humans, these natural resources are further exploited. It highlights the need to quantify the impact humans possibly have on the environment due to occupation and transformation of land. As a starting point of this paper (1 st objective), the land use activities, which may be mainly socio-culturally or economically oriented, are identified in addition to the natural land-based processes and stocks and funds that can be altered due to land use. To quantify the possible impact anthropogenic land use can have on the natural environment, linked to a certain product or service, life cycle assessment (LCA) is a tool commonly used. During the last decades, many indicators are developed within the LCA framework in an attempt to evaluate certain environmental impacts of land use. A second objective of this study is to briefly review these indicators and to categorize them according to whether they assess a change in the asset of natural resources for production and consumption or a disturbance of certain ecosystem processes, i.e. ecosystem health. Based on these findings, two enhanced proxy indicators are proposed (3 rd objective). Both indicators use net primary production (NPP) loss (potential NPP in the absence of humans minus remaining NPP after land use) as a relevant proxy to primarily assess the impact of land use on ecosystem health. As there are two approaches to account for the natural and productive value of the NPP remaining after land use, namely the Human Appropriation of NPP (HANPP) and hemeroby (or naturalness) concepts, two indicators are introduced and the advantages and limitations compared to state-of-the-art NPP-based land use indicators are discussed. Exergy-based spatially differentiated characterization factors (CFs) are calculated for several types of land use (e.g., pasture land, urban land). [ABSTRACT FROM AUTHOR]

The environmental impacts of biomass harvesting can be quantified through the amount of net primary production required to produce one unit of harvested biomass (SPPR-specific primary production required). This paper presents a new calculation framework that explicitly takes into account full food web complexity and shows that the resulting SPPR for toothed whales in the Icelandic marine ecosystem is 2.8 times higher than the existing approach based on food web simplification. In addition, we show that our new framework can be coupled to food web modeling to examine how uncertainty on ecological data and processes can be accounted for while estimating SPPR. This approach reveals that an increase in the degree of heterotrophy by flagellates from 0% to 100% results in a two-fold increase in SPPR estimates in the Barents Sea. It also shows that the estimated SPPR is between 3.9 (herring) and 5.0 (capelin) times higher than that estimated when adopting food chain theory. SPPR resulting from our new approach is only valid for the given time period for which the food web is modeled and cannot be used to infer changes in SPPR when the food web is altered by changes in human exploitation or environmental changes. [ABSTRACT FROM AUTHOR]

Concerns have risen regarding the environmental sustainability of favourable aquaculture-based products, including Pangasius fillets in modified atmosphere packaging (MAP). This study examines issues stemming from resource consumption in a cradle-to-factory gate life cycle analysis of MAP Pangasius, which includes aquaculture, processing living fish to frozen fillets in Vietnam, oceanic transport and processing frozen fillets to MAP in Belgium (Europe). Analysis was performed at the process level using Exergy Flow Analysis (ExFA) and from a life cycle perspective through the Cumulative Exergy Extraction from the Natural Environment (CEENE). The CEENE of MAP equals 669 GJ per tonne of dry matter (DM) of MAP Pangasius. Aquaculture, which is addressed in Huysveld et al. (2013), contains the largest share of the CEENE value (76%), and the three subsequent phases contribute 13%, 5% and 6%, respectively. Consequently, MAP production requires significant amounts of land (42%, primarily for the cultivation of crop-based feed ingredients), water (31%, primarily for pond water renewal) and fossil fuels (21%, primarily for energy demand in processing and transport). Regarding processing and transport, further attention should be paid to the consumption of electricity, water and packaging materials. Improvements should focus on lowering the fillet weight gain due to glazing and/or soaking and on the use and disposal of packaging materials, particularly those used to ship the frozen fillets. Recycling in Belgium reduces 40 GJ per tonne of DM of MAP via replacement of virgin material. MAP Pangasius creates half the resource footprint compared to fresh chicken meat locally produced in Europe despite being imported from Vietnam; this is explained by the lower Feed Conversion Ratio of Pangasius and by the utilization of Pangasius by-products for animal feed in Vietnam, whereas chicken by-products are considered wastes and are incinerated in Europe. [ABSTRACT FROM AUTHOR]

It is still not proven that treatment of sewage in a wastewater treatment plant (WWTP) is (in every case) environmentally friendly. To address this matter, we have applied a state-of-the-art life cycle assessment (LCA) to an energy self-sufficient WWTP in Strass (Austria), its supply chain and the valorization of its ‘products’: produced electricity out of biogas from sludge digestion and the associated stabilized digestate, applied as agricultural fertilizer. Prominent aspects of our study are: a holistic environmental impact assessment, measurement of greenhouse gas emissions (including N 2 O), and accounting for infrastructure, replacement of conventional fertilizers and toxicity of metals present in the stabilized digestate. Additionally, the environmental sustainability improvement by implementing one-stage partial nitritation/anammox (e.g. DEMON ® ) and co-digestion was also assessed. DEMON on the digesters reject water leads to a considerable saving of natural resources compared to nitritiation/denitritation (about 33% of the life cycle resource input), this through the lowering of sludge consumption for N-removal, and thus increasing electricity production via a higher sludge excess. However, its N 2 O emission could be restrained through further optimization as it represents a large share (30–66%) of the plants' damaging effect on human health, this through climate change. The co-substrate addition to the digester resulted in no significant improvement of the digestion process but induced net electricity generation. If respective amounts of conventional fertilizers are replaced, the land application of the stabilized digestate is environmentally friendly through prevention of natural resource consumption and diversity loss, but possibly not regarding human health impact due the presence of toxic heavy metals, mainly Zn, in the digestate. The outcomes show that the complete life cycle results in a prevention of resource extraction from nature and a potential mitigation of diversity loss (though for some impact categories no quantification of associated diversity loss is possible) but it also leads to a damaging effect on human health, mainly via climate change and heavy metal toxicity. Since it is for now impossible to aggregate the impact to these different aspects in a sound manner, it is not yet possible to consider in this case the studied system as environmentally friendly. Generally, the field of LCA needs further development to present a better and single outcome. [ABSTRACT FROM AUTHOR]

Airborne fine particulate matter (PM) is responsible for the most severe health effects induced by air pollution in Europe. Vegetation, and forests in particular, can play a role in mitigating this pollution since they have a large surface area to filter PM out of the air. Many studies have solely focused on dry deposition of PM onto the tree surface, but deposited PM can be resuspended to the air or may be washed off by precipitation dripping from the plants to the soil. It is only the latter process that represents a net-removal from the atmosphere. To quantify this removal all these processes should be accounted for, which is the case in our modeling framework. Practically, a multilayered PM removal model for forest canopies is developed. In addition, the framework has been integrated into an existing forest growth model in order to account for changes in PM removal efficiency during forest growth. A case study was performed on a Scots pine stand in Belgium (Europe), resulting for 2010 in a dry deposition of 31 kg PM2.5 (PM < 2.5 μm) ha-1 yr-1 from which 76% was resuspended and 24% washed off. For different future emission reduction scenarios from 2010 to 2030, with altering PM2.5 air concentration, the avoided health costs due to PM2.5 removal was estimated to range from 915 to 1075 euro ha-1 yr-1. The presented model could even be used to predict nutrient input via particulate matter though further research is needed to improve and better validate the model. [ABSTRACT FROM AUTHOR]

Although natural resources form the basis of our economy, they are not always used in a sustainable way. To achieve a more sustainable economic growth, resource consumption needs to be measured. Therefore, resource footprint frameworks (RFF) are being developed. To easily provide results, these RFF integrate inventory methodologies, at macro level mostly input-output (IO) models, with resource accounting methodologies, of which the Ecological Footprint is probably the best known one. The objective of this work is the development of a new RFF, in which a world IOmodel (Exiobase), providing a global perspective, is integrated with the CEENE methodology (Cumulative Exergy Extraction from the Natural Environment), offering a more complete resource range: fossil fuels, metals, minerals, nuclear resources, water resources, land resources, abiotic renewable resources, and atmospheric resources. This RFF, called IO-CEENE, allows one to calculate resource footprints for products or services consumed in different countries as the exergy extracted from nature. The way the framework is constructed makes it possible to show which resources and countries contribute to the total footprint. This was illustrated by a case study, presenting the benefits of the framework's worldwide perspective. Additionally, a software file is provided to easily calculate results. [ABSTRACT FROM AUTHOR]

Life Cycle Assessment (LCA) is a tool to assess the environmental sustainabiliry of a product; it quantifies the environmental impact of a product's life cycle. In conventional LCAs, the boundaries of a product's life cycle are limited to the human/industrial system, the technosphere. Ecosystems, which provide resources to and take up emissions from the technosphere, are not included in those boundaries. However, similar to the technosphere, ecosystems also have an impact on their (surrounding) environment through their resource usage (e.g., nutrients) and emissions (e.g., CH4). We therefore propose a LCA framework to assess the impact of integrated Techno-Ecological Systems (TES), comprising relevant ecosystems and the technosphere. In our framework, ecosystems are accounted for in the same manner as technosphere compartments. Also, the remediating effect of uptake of pollutants, an ecosystem service, is considered. A case study was performed on a TES of sawn timber production encompassing wood growth in an intensively managed torest ecosystem and further industrial processing. Results show that the managed forest accounted for almost all resource usage and biodiversity loss through land occupation but also for a remediating effect on human health, mostly via capture of airborne fine particles. These findings illustrate the potential relevance of including ecosystems in the product's life cycle of a LCA, though further research is needed to better quantify the environmental impact of TES. [ABSTRACT FROM AUTHOR]

Abstract: Depletion of marine fish stocks has become a global problem. Aquaculture is seen by many as the best way to meet the growing demand for fish products. The question then arises whether aquaculture is a truly environmentally sustainable alternative. Every type of aquaculture is different, therefore each one merits its own case study. To date, Life Cycle Assessment (LCA) studies have mainly examined Western culture systems, although Asia predominates the world aquaculture production by quantity. In this research, we focus on a vertically integrated Vietnamese top exporter of Pangasius food products in the Mekong Delta. Along with a tremendous expansion of this sector in recent decades, intensification coincided with an increased material and energy demand. Therefore, we focus on resource extraction (from cradle to farm gate), expressed as the Cumulative Exergy Extraction from the Natural Environment (CEENE). Hotspots in resource demand are identified over the life cycle stages (juvenile production, feed production and culturing to marketable-sized fish). The life cycle resource footprint includes mainly land (62%, mainly for feed production), water (31%, mainly for on-site farming of the fish) and fossil fuels (4%, mainly for energy needs throughout the feed supply chain). Main methods for reducing this resource demand should be lowering the feed and water input into the ponds and improving the efficiency of the feed supply chain. Pros and cons of closed-loop water-saving systems are discussed. The feed supply chain plays a key role in improving the resource use efficiency. Vietnamese Pangasius producers should be introduced to life cycle thinking and encouraged to pay attention to the environmental performance of their suppliers across the world. For the last goal, a new metric system to score the Feed Conversion Ratio (FCR), i.e. the CEENE FCR, is introduced here. [Copyright &y& Elsevier]

Abstract: To assess the environmental sustainability of industrial products and services, tools such as life cycle assessment (LCA) have been developed. In LCA, the total environmental impact of resource extraction and emissions during a product''s life cycle is quantified. To better quantify this impact, first the alteration of ecosystems induced by those processes needs to be accounted for. Second, the flow networks of ecosystems, responsible for the formation of the extracted resources, should be included in the product''s life cycle. To achieve these two objectives, a tool was selected which studies the flow networks of ecosystems: ecological network analysis (ENA). In ENA, total system indicators are calculated which assess an ecosystem''s functioning (e.g. cycling). Alterations of ecosystems can be represented by changes in the values of those indicators. ENA is based on the computational framework of input–output analysis (IOA). This framework is also used in LCA allowing for a possible extension of a product''s life cycle in an LCA with the ecosystem flow networks of ENA. The ENA/IOA framework itself was revised and improved in this study to better fit in an LCA framework, prior to integration and application in LCA. The major adaptation was to enable physical compartmentalization of the surrounding environment of the studied (eco)system. This allows for a specification of destinations and sources of export and import flows, respectively, which is desired in LCA to assess the impact of these flows. Next to that, the adapted framework was made applicable to non-steady-state systems by applying Finn''s concept (1976, 1977), in which increase, increment, and decrease, depletion, in stock are considered abstract export and import flows, respectively. As an example, the adapted ENA framework was applied to a forest ecosystem. However, there are no standards yet for the different choices in the ENA methodology, which can have an influence on the indicator values. Hence, defining such standards is a next important research step. [Copyright &y& Elsevier]

Oxygen-limited autotrophic nitrification/denitrification (OLAND) is a one-stage combination of partial nitritation and anammox, which can have a challenging process start-up. In this study, start-up strategies were tested for sequencing batch reactors (SBR), varying hydraulic parameters, i.e. volumetric exchange ratio (VER) and feeding regime, and salinity. Two sequential tests with two parallel SBR were performed, and stable removal rates > 0.4 g N l−1 day−1 with minimal nitrite and nitrate accumulation were considered a successful start-up. SBR A and B were operated at 50% VER with 3 g NaCl l−1 in the influent, and the influent was fed over 8% and 82% of the cycle time respectively. SBR B started up in 24 days, but SBR A achieved no start-up in 39 days. SBR C and D were fed over 65% of the cycle time at 25% VER, and salt was added only to the influent of SBR D (5 g NaCl l−1). Start-up of both SBR C and D was successful in 9 and 32 days respectively. Reactor D developed a higher proportion of small aggregates (0.10-0.25 mm), with a high nitritation to anammox rate ratio, likely the cause of the observed nitrite accumulation. The latter was overcome by temporarily including an anoxic period at the end of the reaction phase. All systems achieved granulation and similar biomass-specific nitrogen removal rates (141-220 mg N g−1 VSS day−1). FISH revealed a close juxtapositioning of aerobic and anoxic ammonium-oxidizing bacteria (AerAOB and AnAOB), also in small aggregates. DGGE showed that AerAOB communities had a lower evenness than Planctomycetes communities. A higher richness of the latter seemed to be correlated with better reactor performance. Overall, the fast start-up of SBR B, C and D suggests that stable hydraulic conditions are beneficial for OLAND while increased salinity at the tested levels is not needed for good reactor performance. [ABSTRACT FROM AUTHOR]

The urgency of tackling global environmental issues calls for radical technological and behavioral changes. New prospective (or ex ante) methods are needed to assess the impacts of these changes. Prospective life cycle assessment (LCA) can contribute by detailed analysis of environmental consequences. A new stream of research has taken up the challenge to create prospective life cycle inventory (LCI) databases, building on projections of integrated assessment models to describe future changes in technology use and their underlying environmental performance. The present work extends on this by addressing the research question on how to project life cycle impact assessment methods for water scarcity consistent with prospective LCI modeling. Water scarcity characterization factors are projected from 2010–2050 using the AWARE method, based on SSP‐RCP scenario results of the integrated assessment model IMAGE. This work is coupled with prospective LCI databases, where electricity datasets are adapted based on the energy component of IMAGE for the same scenario. Based on this, an LCA case study of water desalination for the steel industry in Spain is presented. The resulting regional characterization factors show that some regions (i.e., the Iberian Peninsula) could experience an increase in water scarcity in the future. Results of the case study show how this can lead to trade‐offs between climate change and water scarcity impacts and how disregarding such trends could lead to biased assessments. The relevance and limitations are finally discussed, highlighting further research needs, such as the temporalization of the impacts. [ABSTRACT FROM AUTHOR]

The article discusses the importance of cultural ecosystem services (CES), and notes that these should not be abandoned. Topics discussed include description of ecosystem service (ES) and CES in literature; the Millennium Ecosystem Assessment report in which ES is described as the benefits people obtain from ecosystems; and CES, which is describes as recreational, aesthetic, and spiritual benefits.

Waste electrical and electronic equipment (WEEE) constitutes one of the most problematic waste streams worldwide, and accurately estimating the scale of WEEE can assist in tackling its associated issues. However, obtaining an accurate estimation of WEEE remains a challenge because a share of the waste is difficult to calculate. This share stems from the administratively unregistered (so-called "invisible") inflow of electrical and electronic equipment (EEE) into the domestic market. As a first attempt to qualitatively and quantitatively investigate this invisible inflow, this study discusses the nature of this flow in detail and proposes a calculation pathway for quantifying its magnitude. The size of the invisible inflow to a domestic market (assumed equal to invisible sales) is calculated by subtracting the registered, also called "visible", sales from the total sales. The total sales are modeled, whereas the visible sales are derived from statistical data. The method is illustrated by a case study on televisions (TVs) in Vietnam. The results show that from 2002 to 2013, the invisible TV inflow contributed, on average, 15% to the total TV sales (coefficient of variation: 0.21). This average share would increase by approximately 1.0% when the maximum number of TVs used per household increased by 1.0%. However, it would decrease by 1.7% when the visible sales increased by 1.0%. Additionally, the average share of the invisible TV inflow would change from 15% to 27% when an unadjusted constant instead of an adjusted time-varying lifespan is employed. This first estimation of the invisible EEE inflow to the domestic market can be improved with additional knowledge and data in the future. [ABSTRACT FROM AUTHOR]

Aerobic ammonium-oxidizing bacteria (AerAOB) and anoxic ammonium-oxidizing bacteria (AnAOB) cooperate in partial nitritation/anammox systems to remove ammonium from wastewater. In this process, large granular microbial aggregates enhance the performance, but little is known about granulation so far. In this study, three suspended-growth oxygen-limited autotrophic nitrification-denitrification (OLAND) reactors with different inoculation and operation (mixing and aeration) conditions, designated reactors A, B, and C, were used. The test objectives were (i) to quantify the AerAOB and AnAOB abundance and the activity balance for the different aggregate sizes and (ii) to relate aggregate morphology, size distribution, and architecture putatively to the inoculation and operation of the three reactors. A nitrite accumulation rate ratio (NARR) was defined as the net aerobic nitrite production rate divided by the anoxic nitrite consumption rate. The smallest reactor A, B, and C aggregates were nitrite sources (NARR, >1.7). Large reactor A and C aggregates were granules capable of autonomous nitrogen removal (NARR, 0.6 to 1.1) with internal AnAOB zones surrounded by an AerAOB rim. Around 50% of the autotrophic space in these granules consisted of AerAOB- and AnAOB-specific extracellular polymeric substances. Large reactor B aggregates were thin film-like nitrite sinks (NARR, <0.5) in which AnAOB were not shielded by an AerAOB layer. Voids and channels occupied 13 to 17% of the anoxic zone of AnAOB-rich aggregates (reactors B and C). The hypothesized granulation pathways include granule replication by division and budding and are driven by growth and/or decay based on species. specific physiology and by hydrodynamic shear and mixing. [ABSTRACT FROM AUTHOR]