Resources Environment and Sustainability最新文献

In building a sustainable food system, the management of livestock production should avoid nitrogen (N) surplus and ensure animal-sourced food self-sufficiency. Reducing livestock quantities in regions producing excess of animal-sourced food and livestock manure is an effective approach for mitigating manure N surplus. In this study, we considered the eastern regions of China as a case study to quantitatively analyze whether meat self-sufficiency could be met when reducing the livestock quantity to avoid manure N surplus. In addition to considering the baseline scenario, considering the current livestock quantity (scenario C), we defined three strategies corresponding to livestock reduction scenarios: taking meat self-sufficiency as a priority regardless of the manure balance (scenario TB); taking manure N surplus avoidance as a priority regardless of the meat balance (scenario MNB); and considering the most limiting conditions between satisfying meat self-sufficiency and avoiding manure N surplus (scenario LF). A balance index was used to describe the excess (i.e., positive value) or deficiency (i.e., negative value) of meat and manure N. Concerning the whole of eastern China, in scenario LF, the meat balance index (TBI) and manure N balance index (MNBI) were 0.25 and −0.39, respectively, which could satisfy meat demand while avoid manure N surplus (for scenarios C, TB, and MNB, the TBIs were 1.95, 0, and 1.09, and the MNBIs were 0.56, −0.48, and 0, respectively). At the regional level, the regions with meat self-sufficiency accounted for more than 70% in the LF scenario, and manure N surplus could be avoided in all regions. However, southwestern China should adopt further measures, such as trading among adjacent regions and increasing manure fertilizer application, to satisfy the meat demand while avoiding surplus manure N.

The Chain of Custody (CoC) standard tracks the recycled content (RC) of products, in most cases using the Mass Balance model. This model freely allows the selection of allocation methods and timeframes for the RC evaluation. Our work opens a discussion on the potential effects of this freedom in the RC evaluation. Firstly, we defined the general model representing the viable allocation methods and timeframe, and secondly, we applied the model to a case study. The mass balance model simplifies the monitoring of RC and encourages companies to use recycled materials. However, we outline the need for actions on stricter RC calculation and reporting, for instance, by reducing the timeframe of mass balance calculation or promoting the controlled blending model, which guarantees the physical presence of RC in the product. The results provide a basis for policymakers to set requirements for RC evaluation.

Manganese is a strategic metal that has been widely applied in the steelmaking industry and the emerging energy batteries industry. China is the largest manganese importer and consumer, but the critical features of its manganese metabolisms, including its supply and demand, trade, and waste management, remain unclear. By applying dynamic material flow analysis (DMFA) method, this research investigates the evolution of China’s anthropogenic manganese flows and stocks during the period of 2000 to 2021. We found that the demand for manganese had increased almost tenfold in China from 2000 to 2021, mainly used for steelmaking, while the surging demand for manganese in energy batteries had gradually increased. However, China highly relied on importing manganese concentrates due to its limited manganese resources. The cumulative in-use manganese stocks also increased by tenfold and reached approximately 168 million tons (Mt). In addition, manganese flow from the end-of-life (EoL) final products reached 12 Mt in 2021, but few of them were recycled, implying a huge recycling potential. These findings provide valuable insights to prepare more appropriate manganese resource management policies, such as improving domestic mining technologies, enhancing manganese recycling, and diversifying the supply of manganese resources, so that the overall manganese resource efficiency can be improved.

The construction sector, due to its significant environmental impacts, is a focus area for the promotion of a shift towards the circular economy within the EU. A spotlight has been cast on the necessity to reduce construction and demolition waste and prioritise reuse and high-quality recycling. This work centres on selective demolition and design for deconstruction (DfD) as means of achieving these goals. A literature review is carried out, with the two-fold aim of assessing the state of the art in life cycle assessment studies on this topic and developing a taxonomy of applicable selective demolition and DfD solutions, framing it within the context of policy development in the EU. Available measures are identified for different building structural typologies (concrete, timber, masonry, steel), at the material and element level, providing a comprehensive overview of current and developing technologies. A taxonomy is proposed to support users in the identification of available measures and to link the effects thereof in terms of circularity. A literature-based quantitative assessment of current and potential reuse material rates is provided, together with the greenhouse gases (GHG) emission savings associated with reuse, in order to describe the present situation and highlight the potential for improvement. Reuse potential is found to vary between 0%–80%, depending on material and source; current European reuse rates are estimated <15%. In terms of C-footprint, reuse appears beneficial in most cases. The additional GHG savings from reuse relative to alternative end-of-life options span from 1.30 (gypsum) to 5464 (expanded polystyrene) kg CO_2-eq. per tonne of material managed.

The high quality of Information Technology (IT) equipment undoubtedly contributes to the seamless functioning of various industries in today’s digital era. As organizations strive to increase their IT equipment procurement, there is growing concern about its negative environmental impact. This increased environmental consciousness has made it crucial to adopt a sustainable approach to IT equipment procurement that considers factors such as carbon emissions and End-of-Life (EOL) cycle of equipment. Therefore, this research developed a prediction model for IT equipment procurement as the basis of knowledge for an Intelligent Decision Support System based on carbon emissions and EOL phase. The primary aim of this study is to develop a prediction model for IT equipment procurement that allows for the estimation of carbon emissions associated with the equipment. Several models, including K-Nearest Neighbors, Decision Tree, Polynomial Regression, Autoregressive Integrated Moving Average applied to historical procurement data, and Long Short-Term Memory, were tested to determine the most effective. The developed model has proven successful in predicting IT equipment procurement for future periods, achieving an impressive R-squared score of 0.80. This high accuracy demonstrates the model’s effectiveness in assisting organizations to make well-informed and sustainable decisions regarding IT equipment procurement based on precise predictions and estimated environmental impacts. The developed prediction model is expected to optimize the procurement process by considering environmental aspects like carbon emissions and equipment lifecycle.

Urban Green Space management requires a multi-dimensional, evidence-based approach to effectively balance social, environmental, and economic objectives. City administrators currently lack a data-driven framework for allocating resources during constraint scenarios, leading to subjective decisions. Existing literature lacks objective solutions for managing city-scale green spaces, each with its distinct characteristics. Another challenge is handling varied spatial scales required for urban applications. This study proposes a novel goal programming-based model for urban green space management wherein multiple benefit objectives, such as conserving sequestered carbon in trees and enhancing quality and accessibility of parks, as well as handling demand constraints on available resources like water and personnel, are included. The proposed method was demonstrated in two cities with diverse conditions, Berlin and Melbourne, and evaluated on various benefit metrics, such as allocated green space units, resources consumed, and goals achieved. The model was analyzed with resource allocation decisions and goals at different spatial scales. The highest benefit achievement and resource allocation were observed when resources were allocated at the sub-district scale with a city-level target. Alternatively, setting targets at the district level provided a more even resource distribution; however, at the cost of reduced overall benefits. Results show that the proposed method increased the total benefits gained while effectively balancing conflicting goals and constraints. Additionally, it allows incorporating the city’s preferences and priorities, offering a scalable solution for informed decision-making in varied urban applications. Depending on data availability, this approach can be scaled to other cities, including additional benefits and resource constraints as required.

In biological wastewater treatment, the sorption process is an important removal pathway of organic micropollutants from the aqueous phase. Beyond the conventional sorption to biomass and particulate matter, organic molecules can also partition to gas bubbles commonly present in aerated biological processes. This study investigated the partitioning behavior of 21 selected pharmaceuticals to two types of aerobic granular sludge, and the foam generated by aeration. Batch sorption experiments were performed with biologically inactive granules of controlled diameters (0.5–1, 1–2, and >2 mm). Removal during sorption tests was observed for four positively charged micropollutants (sertraline, citalopram, clarithromycin, and erythromycin), four neutral compounds (levonorgestrel, estradiol, ethinylestradiol, and ketoconazole), and one negatively charged pharmaceutical (losartan). This highlights the importance of electrostatic interactions and lipophilic affinity with the solids. For some compounds, the removal increased with time, suggesting that sorption in thick biofilm is limited by molecular diffusion into the biofilm matrix. Furthermore, partitioning of pharmaceuticals to aeration-induced foam was confirmed in separate batch tests. Clarithromycin, erythromycin, ketoconazole, losartan, levonorgestrel, and ethinylestradiol exhibited concentrations in the foam 1.0–5.3 times higher than the initial test values, indicating potential adsorption at the liquid/gas interface for these compounds.

Decarbonizing the transportation sector emerges as a pivotal step in addressing climate change. In recent years, rapid growth in China’s new energy automotive industry has significantly contributed to transportation decarbonization. However, environmental challenges in producing and recycling electric vehicles (EVs) may limit emission reduction benefits. In this study, we establish a comprehensive life cycle assessment model for vehicles to analyze the gap in air pollutant and greenhouse gas emissions between electric vehicles and internal combustion engine vehicles (ICEVs). Based on this model, the environmental benefits of further promoting electric vehicles in China are evaluated. Results reveal that, compared to ICEVs, EVs reduce life cycle emissions of CO₂ by 12%, NOx by 69%, and VOCs by 9%. Primary constraints on EVs in emission reduction are traced to raw material and component production, notably lithium batteries. By 2025, under the low carbon EVs policy scenario, widespread EV production and sales could cut lifecycle emissions by 3.55 million tons of CO₂, 3,6289 tons of NOx, and 4315 tons of VOCs. During the driving stage, these indicators contribute 495%, 124%, and 253%, respectively, to total emission reduction throughout the lifecycle. This study conducts a comprehensive lifecycle analysis of greenhouse gases and various air pollutants for Chinese EVs. It integrates the latest market trends, application progress, and policy guidelines into scenario design, identifying key sources and indicators of atmospheric pollution in the EV production chain. The findings offer valuable policy insights into China’s role in the global emission reduction process.

Date seeds contain various nutrients and bioactive compounds which can be utilized as functional food ingredients in a sustainable manner. This study optimized microwave-assisted extraction (MAE) of bioactive compounds from defatted date seed powder (DSP) and investigated the physicochemical properties of the remaining residues from seeds of three different date varieties (Khalas, Fardh, and Khenaizi). Both, the extracts and the residues were incorporated as functional ingredients in the biscuits. Under optimal conditions: power 700 W, time 6 min, temperature 45 °C, and particle size $<125\mu m$, the total phenolic content (TPC) and total flavonoid content (TFC) were 15.88 mg GAE/g DSP and 8.51 mg QE/g DSP, respectively, while the antioxidant activities were 17.93, 61.68 and 39.74 mmol TE/g DSP for 2,2${}^{{}^{\prime }}$ -azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-picrlthydrazyl (DPPH) and ferric ion reducing antioxidant power (FRAP), respectively. Bioactive properties were significantly different (P<0.05) among three DSP varieties. The main phenolic compounds identified in defatted DSP were benzoic acid, catechin, ferulic acid, caffeic acid, and vanillin. Moisture content, water holding capacity (WHC), and color of the defatted DSP were significantly affected by microwaves. DSP extract and residue fortified biscuits showed enhanced TPC, TFC, and antioxidant properties. This study indicates that date seeds can be successfully used in food products to promote more sustainable food production.

The escalating impacts of human activities on the ecological environment underscore the significance of valuing ecological resources within the paradigm of sustainable development. In this context, the ecological service value (ESV) of the Danjiangkou watershed (Hubei section) was assessed using a revised equivalent factor evaluation method. Additionally, the study determined the human activity intensity (HAI) and employed GeoDetector to delineate the spatial heterogeneity of ESV, thereby investigating the underlying causes. Results show that vegetation coverage attains a high level of 94%, with a minor 1.37% land use change between 2016 and 2020. Secondly, ESV exhibited a substantial variation, rising from 75.55 billion to 79.81 billion yuan, a growth rate of 5.64%. Lastly, the explanatory degree for the synergistic interplay of HAI and expenditure on the spatial variation of ESV surpassed 30%, and the average sensitivity coefficient of up to 0.82 further indicated the apparent impacts of land use and human interference activities on ESV. The study makes an excellent effort to clarify the complex coupling relationships between different land use types and ESV, which could serve as an example and model for other studies in the field.