Search Results (132)

Global urbanization is shifting from incremental expansion to stock optimization, and old residential communities have become important spatial units for low-carbon transition. However, in existing built environments, traditional process-based inventory methods face practical constraints, including missing original drawings, complex site conditions, and severe vegetation obstruction. As a result, systematic accounting of buildings, landscapes, and natural carbon sinks remains difficult. This study integrates life cycle assessment (LCA), BIM reverse modeling, 3D point clouds, DesignBuilder simulation, inventory-based accounting, and i-Tree Eco to construct a life cycle carbon emission accounting framework for old residential communities. The framework links current-condition data reconstruction, quantity take-off, operational energy simulation, landscape inventory accounting, and vegetation carbon sequestration assessment. It is applied to Nanyuan Xincun in Hefei to quantify the community-scale carbon source–sink structure. The results show that Nanyuan Xincun presents a clear operation-led emission pattern, with the operation and maintenance phase accounting for 82.52% of total positive emissions. Within architectural engineering, operation and maintenance accounts for 82.91%, while material production accounts for 13.28%. Landscape engineering shows a more mixed structure, with operation and maintenance accounting for 52.95% and material production accounting for 36.49%. Vegetation carbon sequestration analysis shows that mature trees and shrubs are the main ecological carbon assets. Annual sequestration reaches 16.95 t-CO₂e/a, and trees and shrubs contribute 92.85% of total vegetation carbon storage. Under current vegetation conditions, annual sequestration is equivalent to 32.99% of annual landscape operation emissions, indicating considerable ecological compensation potential. Based on these findings, this study proposes four optimization pathways: operational energy reduction, low-carbon material substitution, construction and demolition waste recycling, and mature tree protection. These pathways provide data support for refined carbon management and low-carbon renewal in existing communities. Full article

This study evaluates the potential of using Granulated Waste Tire Rubber (GWTR) as an alternative raw material in geopolymer mortars an eco-friendly, low-carbon alternative to traditional cement-based systems. The research investigates the synergistic effect of industrial by-products, such as slag (from ferrochrome plants) and fly ash (from thermal power plants), combined with varying proportions of GWTR (1/4, 1/3, and 1/2 by volume). A total of 22 mixtures were prepared using diverse binder pastes, including pure cement, slag-based, and fly ash-based geopolymer systems, alongside their cement-substituted derivatives. The mechanical and physical performances were assessed through compressive strength, flexural strength, and Ultrasonic Pulse Velocity (UPV) tests at 3, 7, 28, and 180 days, complemented by SEM microstructural analyses. The findings indicate that while GWTR significantly reduces the mechanical properties of pure cement matrices, this negative impact is substantially mitigated in geopolymer mortars supplemented with 5–10% cement. Mixtures containing 1/4 GWTR with 90–95% slag or fly ash (M6, M7, M15, M16) yielded the most successful results in terms of both strength and sustainability, specifically, mixtures M7 and M16 because the hybrid binder synergy effectively compensated for the rubber-induced porosity, ensuring a denser matrix and structural-grade compressive strength alongside high sustainability. Significant decreases in performance were observed at higher GWTR ratios, particularly at the 1/2 level. Overall, the study demonstrates that integrating GWTR into optimized geopolymer systems offers a viable pathway for the valorization of environmental waste and minimizing the ecological footprint of the construction industry. Full article

Soybean is a vital crop supporting global food, feed, and biofuel production. Soybean yields have surged, with record yields reaching 14,678 kg/ha⁻¹, though average farm yields remain stagnant at 2770–2790 kg ha⁻¹. The persistent yield gaps leave 44% of potential production unrealized due to climate change, threatening food security. To meet future caloric demands, which are projected to rise by 46.8% by 2050, soybean breeding must prioritize climate-resilient, high-yielding varieties with minimal ecological footprints. In this comprehensive and in-depth review, we synthesized existing literature and Google Patents and reviewed the multifaceted impacts of climate-change driven eCO₂ and stresses (heat, drought, flooding, salinity, and pathogens), revealing non-linear interactions where eCO₂ may not compensate yield losses under combined stresses. We then highlight key strategies for soybean breeding under climate-change scenario. To this regard, we provide a detailed trait-by-trait breeding roadmap covering seed number, seed size, seed weight, protein-oil balance and their metabolic trade-offs, above and below ground plant architecture, nitrogen fixation and nodulation dynamics, root system architecture, water use efficiency, canopy architecture, flowering time regulation, early maturity etc., in light of specific genes and validated strategies. We explicitly discuss the novel strategies including deeper understanding of traits, abiotic stress physiology, changing pathogen dynamics, phenomics, (multi-)omics, machine learning, and modern biotechnological techniques for developing future soybean varieties. We provide a future roadmap prioritizing specific actions, including engineering climate-resilient ideotypes through gene stacking, optimizing nitrogen fixation and nutrition under stresses leveraging omics data, pan-genome, wild soybean, speeding breeding hubs, and participatory farmer-network validation, while redefining the future soybean breeder would be a hybrid orchestrator of data and dirt. This review establishes a foundational framework for translating climate-adaptive morphological, biochemical, physiological, omics, agronomic, phenomics, and biotechnological insights into actionable breeding strategies, thereby guiding policy-driven investment in soybean improvement programs targeting 2050 and beyond. Full article

Promoting pesticide reduction is a key step toward green vegetable production and ecological safety. Based on survey data collected from 356 leek growers in Weifang City—the largest facility-based vegetable production base in Shandong Province—this study empirically estimates the ecological compensation standard associated with pesticide-reduction behavior. The estimation employs a contingent valuation method (CVM) using non-parametric kernel density estimation for conditional value assessment, combined with the Heckman two-step model to address potential sample selection bias. The results show that 79.3% of respondents are willing to participate in an eco-compensation program for pesticide reduction; the main reason for refusal is “the higher reduction costs and lower profits”. The expected compensation level ranges from 614.94 to 620.57 yuan per mu (1 mu is approximately 0.165 acres) per year. Gender, share of Chinese chives (Allium tuberosum) income, trust in extension agents, and government penalties for excessive spraying significantly raise the required compensation, whereas age and knowledge of eco-compensation significantly lower it. Therefore, a sustainable compensation scheme co-driven by government and market should be established, combining cash, technical and in-kind support, and adopting tiered compensation schemes that reflect different reduction intensities. Full article

In this paper, the dynamic modeling and integrated simulation of a ship microgrid system designed to enhance power quality and energy efficiency in electric propulsion vessels are proposed. The proposed system consists of a photovoltaic (PV) array, a battery energy storage system (BESS), a diesel generator, and a propulsion system, all of which are organically integrated through power conversion devices. To compensate for the intermittent nature of solar power, a control strategy featuring Maximum Power Point Tracking (MPPT) for the PV system and bidirectional DC/DC converter control for the battery was implemented. Specifically, a control logic to stabilize the system output in response to the fluctuating loads of the electric propulsion system was developed using PSCAD (v50) software. The simulation results demonstrate that the proposed control strategy maintains DC-link voltage deviation within ±1.8% and achieves a settling time of less than 0.8 s while optimizing propulsion efficiency (peak-shaving ratio 25–30%) under both constant and variable speed operating conditions. Battery SOC variation is limited to 18–88%, preventing overcharge or discharge. This research provides a foundational framework for the design of energy management systems (EMSs) and grid stability assessments for future eco-friendly electric propulsion ships. Full article

The cement industry, a major contributor to global CO₂ emissions, urgently requires sustainable solutions that maintain or enhance material performance. This study investigates the efficacy of Microbially Induced Calcite Precipitation (MICP) as a partial cement replacement strategy by incorporating two distinct microorganisms, the bacterium Bacillus subtilis (B1) and the fungus Aspergillus fumigatus (B2), into cement mortar. The experimental design involved a significant 30% reduction in total cement content compared to the control mix, with each microorganism added at a dosage of 5% by cement weight. Flexural performance was assessed via three-point bending tests at 7, 28, and 56 days. Microstructural and chemical analyses were conducted using X-ray Diffraction (XRD), X-ray Fluorescence (XRF), and Scanning Electron Microscopy (SEM) to elucidate the underlying mechanisms. The results demonstrate that the incorporation of both microorganisms effectively compensated for the reduced cement content, with the A. fumigatus mix (B2) showing a marked enhancement in flexural behavior, achieving a 4.3% increase over the full-cement control mix at 56 days. This superior flexural performance is attributed to its hyphal scaffolding and crack-bridging effect, which contributes to improved toughness. XRD and XRF analyses confirmed the formation of additional biogenic calcium carbonate (CaCO₃) and provided qualitative insights into matrix densification. This study validates the use of A. fumigatus via the MICP technique as a structurally efficient and eco-friendly pathway to produce high-performance mortars with enhanced flexural properties and a substantially reduced carbon footprint, offering a critical alternative for sustainable cementitious materials. Full article

To explore the potential of phosphogypsum for resource utilization in asphalt pavements, this study evaluated its feasibility as a warm-mix asphalt (WMA) additive and investigated its influence on the rheological properties of asphalt binder. Phosphogypsum warm-mix asphalt was prepared by incorporating varying dosages of phosphogypsum warm-mix additive (PGWA) into both base asphalt and styrene–butadiene–styrene (SBS)-modified asphalt. The high-, medium-, and low-temperature performance of phosphogypsum warm-mix asphalt was evaluated using rheological tests. The results revealed that the complex modulus of PGWA-added base asphalt was higher than that of the base asphalt, with only minor changes in phase angle. The incorporation of the SBS modifier significantly enhanced the stiffness and elasticity of the asphalt binder. Compared with the control asphalt, PGWA-added asphalt exhibited lower creep strain and accumulated strain, higher creep recovery rates, and smaller non-recoverable compliance under the same stress level, indicating an improved resistance to high-temperature permanent deformation. PGWA increased the cumulative damage capacity and extended the fatigue life of the asphalt binder. Although the PGWA slightly reduced the low-temperature performance, the SBS modifier effectively compensated for this drawback. The Burgers model accurately captured the low-temperature rheological behavior of PGWA-added asphalt. Overall, PGWA-added asphalt demonstrated excellent rheological performance and high application potential, offering a promising pathway for the resource utilization of phosphogypsum and the development of sustainable, eco-friendly pavement materials. Full article

Although blood transfusion eco-compensation—a metaphorical term in the Chinese eco-compensation literature referring to short-term direct compensation—can balance stakeholder interests in securing ecological flows (e-flows) in water-scarce rivers, it often fails to enhance the productivity of disadvantaged stakeholders or expand long-term development opportunities. To overcome this limitation, this study introduces hematopoiesis eco-compensation, a metaphorical term for capacity-building, longer-term development-oriented compensation that improves irrigation water-use efficiency and agricultural productivity through water-saving infrastructure upgrades, enhanced irrigation technologies, and technical training. Based on this distinction, we developed a hybrid eco-compensation mechanism integrating the two approaches using a cost–expenditure method and applied it to the mainstream section of the Weihe River and the Baojixia Yuanshang Irrigation District in Northwest China under typical hydrological conditions. The main findings are as follows: (1) Compensation standards for both approaches increase with higher ecological flow targets, with average values of 2762 CNY ha⁻¹ and 1386 CNY ha⁻¹, respectively. (2) The two approaches differ in terms of participants, standards, and implementation methods, yet they are complementary and indispensable under current conditions. (3) Hematopoiesis eco-compensation generates positive ecological and economic effects, increasing the annual value of riverine ecosystem services by approximately 126 million CNY and the annual economic benefits of the irrigation district by approximately 467 million CNY. This study provides a theoretical foundation and practical guidance for establishing long-term compensation mechanisms to maintain ecological flows in water-scarce regions. Full article

To address the susceptibility of traditional concrete to explosive spalling and the lack of in situ damage-monitoring methods at high temperatures, in this study, a novel self-sensing, high-temperature-resistant Engineered Cementitious Composite (ECC) was developed. The matrix contains eco-friendly glass sand reinforced with a hybrid system of polypropylene fibers (PPFs) and carbon fibers (CFs). The evolution of mechanical properties and the multimodal self-sensing characteristics of the ECC were systematically investigated following thermal treatment from 20 °C to 800 °C. The results indicate that the hybrid system exhibits a significant synergistic effect: through PFFs’ pore-forming mechanism, internal vapor pressure is effectively released to mitigate spalling, while CFs provide residual strength compensation. Mechanically, the compressive strength increased by 51.32% (0.9% CF + 1.0% PPF) at 400 °C compared to ambient temperature, attributed to high-temperature-activated secondary hydration. Regarding self-sensing, the composite containing 1.1% CF and 1.5% PPF displayed superior thermosensitivity during heating (resistivity reduction of 49.1%), indicating potential for early fire warnings. Notably, pressure sensitivity was enhanced after high-temperature exposure, with the 0.7% CF + 0.5% PPF group achieving a Fractional Change in Resistivity of 31.1% at 600 °C. Conversely, flexural sensitivity presented a “thermally induced attenuation effect” primarily attributed to high-temperature-induced interfacial weakening. This study confirms that the “pore-formation” mechanism, combined with the reconstruction of the conductive network, governs the material’s macroscopic properties, providing a theoretical basis for green, intelligent, and fire-safe infrastructure. Full article

Integrated urban–rural development is an inevitable requirement of regional development. Developing green industries based on rural ecological resources are important approaches to promoting urban–rural integration. The National Key Ecological Function Zones (NKEFZ) policy focuses on safeguarding national ecological security. However, whether the resulting ecological improvements can, through the realization of ecological value, provide momentum for urban–rural integration remains unclear in existing research. This study uses a sample of 284 prefecture-level cities in China from 2006 to 2023, treating the establishment of NKEFZ as a quasi-natural experiment. First, the study constructs a “Driving-constraining” bidirectional theoretical framework, and then uses the entropy weight method to measure the level of urban–rural integration, which is selected by 18 sub-indicators from the populational, spatial, and economic dimensions. Finally, a multi-period difference-in-differences (DID) model is constructed to test the impact of NKEFZ on urban–rural integration, and the transmission mechanisms and heterogeneity are explored. The results indicate the following: (1) Following the implementation of the NKEFZ policy, it shows an overall inhibitory trend on urban–rural integration, consequently slowing the progress of urban–rural integration. The inhibitory effects are particularly pronounced in spatial and economic integration dimensions, and these results are robust. (2) Constrained industrial upgrading and increased fiscal pressure on local governments are the main mechanisms behind the slowed urban–rural integration. (3) Due to differences in policy coverage and the heterogeneous characteristics of city locations, the negative effects of the policy are more pronounced in cities with a high proportion of key ecological function counties, as well as in prefecture-level cities in central and western regions. Based on these findings, it is suggested to promote high-quality urban–rural integration in eco-priority areas through pathways such as developing ecological industries, improving the ecological compensation system, and clarifying central–local collaborative governance. Full article

The uncoordinated water–sediment relationship, fragile eco-environment and unbalanced economic development in the Wei River Basin (WRB) pose serious challenges to its high-quality development. Most existing studies focus on static structures or single elements, making it difficult to systematically reveal the complex interrelationships among ecosystem services (ESs) supply, transmission and demand. To address this issue, this paper innovatively combines the “system perspective” with the “flow network model”. From the perspective of flood-sediment transport, eco-environmental and socio-economic (FES) subsystems, we take the WRB as its research object and systematically analyzes the supply–demand relationship of ESs, the pathways of the ESs flows and ecological compensation (EC) strategies at multiple scales. By constructing a supply–demand assessment model for six types of ESs combined with the water-related flows model, the enhanced two-step floating catchment area method and the gravity model, this paper simulates the ESs flows driven by different transmission media (water, road and atmosphere). The results showed the following: (1) a significant spatial mismatch was observed between the high-supply areas at the northern foothills of the Qinling Mountains and the high-demand areas in the Guanzhong Plains. Furthermore, the degree of this mismatch increased with decreasing scale. (2) The pathways of different ESs flows were influenced by their respective transmission media. The water-related flows passed through areas along the Wei River and the Jing River. The carbon sequestration flows were identified in the upper reaches of the Luo River and between the core urban agglomerations of the Guanzhong Plains. The crop production flows were significantly influenced by the scale of urban crop demand, radiating outward from Xi’an City. (3) At the county and watershed scales, The EC fund pools of 7.5 billion yuan and 2.6 billion yuan were formed, respectively. These EC funds covered over 90% of the areas. These findings verify the applicability of the “FES subsystems” framework for multi-scale EC and provide a theoretical basis for developing an integrated EC mechanism across the entire basin. Full article

The responses of agricultural households are the central link in China’s eco-compensation, which directly determines the efficiency and effectiveness of compensation. This article reviewed the connotation, influencing factors, and ultimate effectiveness of agricultural households’ response to eco-compensation in China. The results indicated that agricultural households’ response to eco-compensation mainly includes reducing production intensity, optimizing production methods, and changing livelihood types. On this basis, taking protected objects such as farmland, grassland, forests, and watersheds as examples, the specific connotation of the responses was explained. Subsequently, according to policy mechanisms, sustainable livelihood theory, and planned behavior theory, the factors that affect agricultural households’ responses have been sorted out, forming a systematic factor system framework. In addition, focusing on the policy objectives of eco-compensation, the research progress on the economic and ecological effects of agricultural households’ responses, and the final results were summarized. Finally, this article identifies four shortcomings in the current research, namely imbalanced research fields, incomplete contextual impact, nonspecific ecological effects, and immature improvement strategies. The future literature should strengthen research in key fields and areas, focus on the correlation between contexts and responses, integrate multiple disciplines to accurately evaluate ecological effects, and demonstrate the improvement mechanism of agricultural households’ responses. Full article

Forest carbon sinks (FCS)—referring specifically to ecosystem-based carbon sequestration provided by forest ecosystems—are being increasingly recognized as a strategic form of natural capital under China’s “dual carbon” goals. While the ecological value of FCS is being translated into economic benefits through carbon markets, eco-compensation, and green finance, the extent to which ecosystem carbon sinks can continuously drive regional economic growth—and how such effects differ across regions—remains insufficiently understood. Using panel data for 294 Chinese prefecture-level cities from 2010 to 2022, this study employs dynamic panel methods to examine the dynamic, nonlinear, and heterogeneous impacts of ecosystem-based FCS on economic growth. The results show that (1) FCS significantly promote economic growth but follow an inverted U-shaped pattern, indicating diminishing marginal returns; (2) notable regional heterogeneity exists, with the strongest effects in central and western regions, while eastern cities exhibit weaker responses due to structural and spatial constraints; and (3) clear threshold effects are present, suggesting that industrial upgrading, urbanization, and moderate government intervention can amplify the economic contribution of FCS. These findings clarify the mechanism through which FCS transitions from ecological assets to economic capital, providing theoretical and empirical support for sustainable forest management, ecological-industrial integration, and carbon market optimization in the pursuit of carbon neutrality. Full article

More than half of the world’s highly regulated rivers are currently experiencing an unsustainable balance between ecological protection and economic development. The value realization of river eco-products is considered a key pathway to addressing this challenge; however, its effectiveness remains to be empirically verified. Therefore, the objective of this study is to develop an integrated framework for evaluating the sustainability of river ecological protection and economic development through eco-product value realization. The framework integrates the classification of river eco-products, the estimation of their potential and realized values, and the analysis of value realization pathways. Taking the Baoji section of the Weihe River (BSWHR) as a case study, the framework is applied with hydrological, hydraulic, and socio-economic datasets to empirically evaluate the coordination between ecological protection and economic development. The main results showed that: (1) River eco-products are divided into three types: public, operational, and physical operational eco-products; (2) The potential ecological value of all river eco-products in the BSWHR is estimated at 549 million CNY; (3) The realized value of all river eco-products is 288.75 million CNY under current realization paths, corresponding to a sustainability index of 0.63, indicating that the BSWHR is less sustainable and represents an asset liability river; and (4) Enhancing the protection level of river ecological flow (e-flow) and establishing a multi-stakeholder compensation mechanism can improve the sustainability of ecological protection and economic development in highly regulated rivers. The proposed framework provides a practical basis for assessing river sustainability and guiding the effective allocation of ecological protection funds. Full article

This study investigates the combined use of recycled concrete aggregate (RCA) and steel fibers—industrial (ISF), recycled (RSF), and hybrid ISF/RSF (HSF)—to enhance the mechanical performance, freeze–thaw durability, and environmental efficiency of roller-compacted concrete pavement (RCCP). Twenty mixtures incorporating two RCA levels (0% and 25%) and different fiber systems were tested. The results showed that, although RCA slightly reduced strength, hybrid fibers effectively compensated for this loss, improving toughness, tensile capacity, and resistance to freeze–thaw degradation. A life-cycle assessment demonstrated that substituting natural aggregates and industrial fibers with RCA and RSF lowers the embodied carbon and energy demand. A multi-criteria decision analysis identified mixtures with 25% RCA and hybrid fibers (0.9% HSF) as the most balanced solutions, combining an improved performance with a reduced environmental burden. The findings highlight hybrid fiber-reinforced, RCA-based RCCP as a practical and eco-efficient option for sustainable pavement infrastructure. Full article