Environmental Resources Research Articles

Modelling Soil Moisture Balance for Okra Cultivars in Makurdi Agro Climate Using Decision Support System for Agro Technology Transfer (DSSAT)

Abstract: Soil moisture balance from okra (abelmoschus esculentus) field was performed on experimental plot of the Department of Agricultural and Environmental Engineering, Joseph Sanwuan Tarka University Makurdi -Nigeria. Field and laboratory experiments were conducted on four okra cultivars planted and irrigated by drip system at different levels (80% (I1), 60% (I2), 45% (I3), and 15% (I4)) according to the agronomic practices of okra. Decision Support System for agro technology Transfer (DSSAT) model for the Crop Environment Resource Synthesis (CERES) was used to model soil moisture balance by linear regression (multivariate analysis of variance, (MANOVA)) and validated. The soil was sandy loam with high field capacity (FC) at I4 and nearly uniform drainage (D) except for I4.. Runoff (R) decreases from 35.71 for I1 to 0.07 for I4 implying that R, D and change in water storage (∆S) are functions of the amount and duration of irrigation. The models reported an acceptable deviation from the ideal line of the R and ∆S at higher values confirming degree of the correlation between the observed and predicted dataset but experienced difficulties with estimating lower values due to lower magnitudes in irrigation. From the foregoing it is concluded that decreasing water application results in an increase in irrigation and the reverse is also true.

Alzheimer's Disease Mortality Rate: Correlation with Socio-Economic and Environmental Factors.

The progressive increase in the number of deaths caused by Alzheimer's disease (AD) in Brazil and around the world between 2010 and 2020 raises questions in scientific society. At the same time, there is also an increase in life expectancy at birth (LEB). Thus, the aim of this study was, for the first time, to compare the increase in AD mortality rate (ADMR) in Brazilian regions over the years 2010 to 2020 with the increase in LEB, and investigate the possible correlation between these demographic transition phenomena and pesticide sales and exposure during this period. Data were extracted from the Brazilian Institute of Geography and Statistics (IBGE), from the Department of Informatics and Technology of the Brazilian Ministry of Health (DATASUS) and from the Brazilian Institute of the Environment and Renewable Natural Resources (IBAMA). There was a significant increase in life expectancy at birth and in ADMR over the years between 2010 and 2020 in all Brazilian regions, with the female population in the South region being the most affected. In conclusion, there is a strong positive correlation between the increase in ADMR and LEB; ADMR and Human Development Index (HDI) and ADMR and pesticide sales and exposure in Brazil over the years studied.

Psychometric properties of the newly developed self-report environmental determinants of health questionnaire (EDH-Q): development and validation

BackgroundThe environmental determinants of health (EDH) have a significant impact on people’s physical, mental, and social wellbeing. Everyone needs access to environmental resources of all types, including food, materials, and energy, to survive. Currently, no valid and reliable instrument exists for evaluating individuals’ perceived levels of EDH. Hence, the purpose of this study was to develop and validate the environmental determinants of health questionnaire (EDH-Q) among undergraduate students in Nigeria.MethodWe conducted a cross-sectional survey among undergraduate students in Nigeria to assess the psychometric properties of the newly developed Environmental Determinants of Health Questionnaire (EDH-Q). Respondents were selected using a convenience sampling approach to evaluate their perceptions of environmental determinants of health. The Content Validity Index (CVI) and Face Validity Index (FVI) were calculated to ascertain the scale’s content validity and response process validity, respectively. Additionally, exploratory factor analysis (EFA), confirmatory factor analysis (CFA), composite reliability (CR), average variance extracted (AVE), Cronbach’s alpha, and intraclass correlation coefficient (ICC) were computed to assess the scale’s construct validity.ResultsThe study involved 300 respondents in the EFA (males 55.7%, females 44.3%) and 430 respondents in the CFA (males 54.0%, females 46.0%). In the EFA, two constructs were identified (the natural environment and the built environment). The EFA model was able to explain 63.57% of the total cumulative variance, and the factor correlation was 0.671. The whole scale Cronbach’s alpha value was 0.947, while the two constructs’ Cronbach’s alpha values were 0.918 (natural environment) and 0.935 (built environment). In the CFA, six pairs of error covariances were included between items within the same construct to improve the fit indices of the initial proposed measurement model. The final re-specified measurement model showed that the EDH-Q, which has two constructs and 18 items, has adequate construct validity (CFI = 0.948, TLI = 0.938, SRMR = 0.046, RMSEA = 0.052, and RMSEA p-value = 0.344). The CRs were 0.845 (natural environment) and 0.854 (built environment). The ICCs were 0.976 (natural environment) and 0.970 (built environment).ConclusionThe results show that the newly created EDH-Q has sufficient construct validity and may be utilized to assess participants’ perceptions of their level of EDH. Researchers should examine this instrument in populations with different age ranges and other demographic characteristics, as the present study only applied it to undergraduate students who may share similar characteristics.

Changes in land use dynamics following the Fundão dam collapse in the Doce River Basin, Brazil

Although regarded as “unexpected,” the collapse of the Fundão tailings dam in 2015 resulted from the synergistic interplay between the capitalist logic of environmental resource exploitation and environmental degradation in the Doce River Basin (DRB). Our objective was to assess whether this disaster altered land-use dynamics in the DRB. To achieve this, we characterized land-use transitions by comparing changes over three years before (2012–2015) and after (2016–2019) the disaster. We differentiated municipalities adjoining the affected rivers from the remaining municipalities. We evaluated anthropogenic and natural driving forces as explanatory variables: farmland to natural vegetation (land abandonment) or natural vegetation to farmland (farmland expansion). We detected two main driving forces of land abandonment, precipitation and temperature, both before and after the dam collapse. Still, there was a shift between periods: before the dam collapse, the drivers of land abandonment differed between municipalities adjoining and those not adjoining the affected rivers. After the disaster, all municipalities shared the same drivers for land abandonment. For farmland expansion, we detected five drivers for the period before (temperature, precipitation, natural vegetation area, roads, and municipality area) and five drivers after (urban area, slope, natural vegetation area, roads, and municipality area) the dam collapse. Thus, we detected a change in the drivers but no distinction between municipalities adjoining and not adjoining the affected rivers. Our results evidenced a direct effect of the disaster on land abandonment but not farmland expansion, where the observed temporal changes may be related to temporal changes independent of the disaster. Our work shows that the collapse of the Fundão mining dam changed the drivers of “land abandonment,” which may be due to anthropic avoidance of using Doce River’s water for farmland or to a change in socio-economic drivers, such as those related to the monthly financial compensation of affected farmers.

Application of Artificial Intelligence in Glacier Studies: A State-of-the-Art Review

Assessing glaciers using recent and historical data and predicting the future impacts on them due to climate change are crucial for understanding global glacier mass balance, regional water resources, and downstream hydrology. Computational methods are crucial for analyzing current conditions and forecasting glacier changes using remote sensing and other data sources. Due to the complexity and large data volumes, there is a strong demand for accelerated computing. AI-based approaches are increasingly being adopted for their efficiency and accuracy in these tasks. Thus, in the current state-of-the-art review work, available research results on the application of AI methods for glacier studies are addressed. Using selected search terms, AI-based publications are collected from research databases. They are further classified in terms of their geographical locations and glacier-related research purposes. It was found that the majority of AI-based glacier studies focused on inventorying and mapping glaciers worldwide. AI techniques like U-Net, Random forest, CNN, and DeepLab are mostly utilized in glacier mapping, demonstrating their adaptability and scalability. Other AI-based glacier studies such as glacier evolution, snow/ice differentiation, and ice dynamic modeling are reviewed and classified, Overall, AI methods are predominantly based on supervised learning and deep learning approaches, and these methods have been used almost evenly in glacier publications over the years since the beginning of this research area. Thus, the integration of AI in glacier research is advancing, promising to enhance our comprehension of glaciers amid climate change and aiding environmental conservation and resource management.

Sozology instead of ecology, other direction for ecosystem services and environmental protection-on the example of the Silesian–Kraków region, Southern Poland

Known mostly in Poland, formulated by prof. Goetel, science—sozology, perfectly corresponds to today’s developing pro-environmental activities. Sozology combines both concerns for the precious values of primaeval nature and the management of man transformed areas. It includes civilisation changes, climate change, and access to natural resources. The article discusses five main research directions: (1) Protection of the natural environment and mineral resources, (2) Rational spatial management, (3) Post-exploitation management of industrial areas, (4) Analysis and prevention of environmental changes and (5) Sozology and Eco-geosystem services. The authors of the article point to the need to integrate specialists from various fields who can jointly solve environmental problems. The world constantly needs new motivations to develop while preserving non-renewable resources (space and minerals). In Poland, science has gained popularity only among a narrow group of scientists who do not try to solve difficult problems on their own that require interdisciplinary action. The frequent dead ends of today’s environmental trends indicate that the word ecological is often not enough. If we use a sozological approach, it will turn out to be much more adequate for our current stage of development. Sozology may be the next direction and philosophy of life on Earth. Its goal is to protect resources so that they can be used for as long as possible.

Optimized wastewater management utilizing multivariate statistical analysis: a case study of the Mascara wastewater treatment plant, Algeria.

Effective wastewater management is crucial in regions experiencing water scarcity and environmental stressors, such as pollution and climate change. Optimizing treatment processes is essential for achieving environmental sustainability. This study aims to highlight the importance of effective wastewater management strategies, particularly in regions facing water scarcity. Our objective was to identify key factors influencing the treatment process. Therefore, we evaluated associations between physicochemical parameters using multivariate statistical methods, including Principal Component Analysis (PCA) and Hierarchical Ascendant Classification (HAC). Our findings categorize the monthly water samples into three distinct groups based on levels of organic pollution: the first group (July, August, and September) is characterized by high oxygenation levels and significantly low organic pollution, indicating optimal system operation. The second group (April, October, November, and December) exhibits low oxygenation and low organic pollution, promoting sludge settling and pollutant reduction. The third group (January, February, March, May, and June) shows significantly high organic pollution and low oxygenation, which corresponds to unfavorable environmental conditions. Our study demonstrates the effectiveness of multivariate statistical methods in optimizing wastewater treatment processes, providing crucial insights for environmental sustainability and water resource management.

Spatiotemporal Evolution of Urban Land Green Utilization Efficiency and Driving Factors: An Empirical Study Based on Spatial Econometrics

Green development is an inevitable choice for sustainable development under the constraints of environmental resources. This paper attempts to explore the connotation of urban land green utilization efficiency (LGUE) and reveal its spatial differentiation characteristics. This study adopts the super-SBM model to measure LGUE from 2009 to 2022 and analyzes the spatiotemporal variation rules. Then, the study reveals the spatial influencing factors of LGUE, drawing the following conclusions: (1) the average efficiency value of LGUE at the national level is still at a low level, but it is on an upward trend. There are significant differences in LGUE among the eastern, central, and western regions, with the highest LGUE in the eastern region and the lowest in the western region. (2) The spatial distribution of LGUE in various cities across the country is not entirely random but shows significant spatial autocorrelation characteristics. The improvement in LGUE in a region can improve the surrounding region's LGUE. (3) Economic development level promotes the improvement of local city LGUE, but its impact on LGUE of surrounding neighboring cities is not significant; local city industrial structure upgrading can improve LGUE in both local and neighboring cities; foreign investment in local cities can promote LGUE in both local and neighboring cities; the increase in population density will hinder LGUE in local cities but improve surrounding cities LGUE. The intervention degree of local city government will suppress the improvement of LGUE in both local and neighboring cities.

Synthesis of biobased Phosphorus-Nitrogen-Silicon ceramizable flame retardant and its flame retardancy effects on EPS

The rising interest in eco-friendly flame retardants marks a notable trend in the industry. However, the challenge remains that most flame retardants, while achieving high flame retardant properties, struggle to balance environmental sustainability and resource utilization. This work delves into the green synthesis and mechanism of action of ceramizable flame retardants. Using phytic acid (PA) and urea (U) as raw materials, ionic complexation assembly in water, employing polydopamine (PDA) as an adhesive, to develop an environmentally friendly, bio-based synergistic flame retardant (PAU) is conducted. Building upon this groundwork, the addition of the ceramic filler kaolin (KL) and the fluxing agent sodium carbonate (Na2CO3) physically modifies the PAU, resulting in a novel eco-friendly, bio-based, ceramifiable flame retardant (PAUK). Employing the prepared PAUK through an effective surface coating technique, a lightweight and scratch-resistant flame-retardant expanded polystyrene insulation board (EPS-PAUK) is created. The best EPS-PAUK composite in our study exhibits an oxygen index of 52.5, achieves a V-0 UL-94 rating, and features excellent smoke suppression and compression strength up to 67.8 kPa, while nearly maintaining the lightweight characteristics of the EPS insulation boards. This bio-based, ceramifiable flame retardant system offers a new approach for producing lightweight, highly efficient flame-retardant and high-performance polymers.

Teaching introductory biomechanics course in low resource environment

Biomechanics originates at the interface of engineering mechanics and biological science. Biomechanics is an essential course for students of various disciplines, such as sports medicine, kinesiology, exercise science, orthopedics, medical sciences, biomedical engineering, and biological sciences. An introductory biomechanics course involves concepts of biology, mathematics, and mechanics that students find difficult to understand. This results in incomplete and ineffective learning of biomechanical concepts. The professional competence of a biomechanics student significantly depends on learning outcomes. Designing and developing an effective instructional methodology for an introductory biomechanics course that can improve students’ learning outcomes is challenging. Teaching a biomechanics course in a low-resource environment lacking expensive biomechanics experiment equipment and commercial software is an additional challenge. Literature suggests that active learning instructional techniques can help overcome these challenges. The present study reviews active learning methods such as Experiential Learning, Problem-based Learning, Challenge-based Instructions, Just-in-Time Teaching, Game-based Learning, and Mobile Learning, which have the potential to enhance the learning outcomes of biomechanics students during an introductory biomechanics course. The present study also discusses the possibility and effectiveness of these pedagogical approaches while teaching an introductory biomechanics course in low-resource environments. A curriculum designed (lecture and laboratory modules) for effectively delivering biomechanics courses to students in low-resource environments has been suggested. This study also highlights open-source software packages and tools that are helpful for teaching and learning introductory biomechanics in low-resource settings.

Examining the relationship between psychosocial adversity and inhibitory control: an fMRI study of children growing up in extreme poverty.

Exposure to psychosocial adversity (PA) is associated with poor behavioral, physical, and mental health outcomes in adulthood. As these outcomes are related to alterations in developmental processes, growing evidence suggests that deficits in executive functions-inhibitory control in particular-may, in part, explain this relationship. However, literature examining the development of inhibitory control has been based on children in higher resource environments, and little is known how low resource settings might exacerbate the link between inhibitory control and health outcomes. In this context, we collected fMRI data during a Go/No-Go inhibitory control task and PA variables for 68 children 5 to 7 years of age living in Dhaka, Bangladesh, an area with a high prevalence of PA. The children's mothers completed behavioral questionnaires to assess the child's PA and their own PA. Whole-brain activation underlying inhibitory control was examined using the No-Go versus Go contrast, and associations with PA variables were assessed using whole-brain regressions. Childhood neglect was associated with weaker activation in the right posterior cingulate, whereas greater family conflict, economic stress, and maternal PA factors were associated with greater activation in the left medial frontal gyrus, right superior and middle frontal gyri, and left cingulate gyrus. These data suggest that neural networks supporting inhibitory control processes may vary as a function of exposure to different types of PA, particularly between those related to threat and deprivation. Furthermore, increased activation in children with greater PA may serve as a compensatory mechanism, allowing them to maintain similar behavioral task performance.

Efficient removal and upcycling of pollutants in wastewater: a strategy for reconciling environmental pollution and resource depletion crisis

Efficient removal and upcycling of pollutants in wastewater: a strategy for reconciling environmental pollution and resource depletion crisis

Climate drives body mass changes in a mountain ungulate: shorter winters lead to heavier Alpine ibex

Climate affects seasonality and plant phenology, which can influence seasonal body mass dynamics of herbivores in temperate environments. We investigated long‐term trends of seasonal body mass changes in male Alpine ibex Capra ibex. We used SEM to test direct and indirect relationships between body mass, mass changes and environmental and climatic variables. Individually recognizable Alpine ibex were weighed repeatedly between 2000 and 2022 in Gran Paradiso National Park (Italy). Autumn mass increased substantially over these two decades, up to 15% in some age classes. Over the same time frame, both summer mass gain and winter mass loss decreased, suggesting that heavier autumn body mass was due to the cumulative effects of reduced mass loss over several winters. The environmental factor with the strongest effects on winter mass changes was the starting date of vegetation green‐up at low altitude, where ibex gather after winter to feed on new growth vegetation. Early springs led to lower winter mass loss, likely because ibex relied on stored fat for a shorter period and had greater access to forage. High population density also increased winter mass loss. Environmental conditions and resource availability, possibly also influenced by density in winter and early spring, seem therefore to directly affect the body mass dynamics of male Alpine ibex, while the effect of summer conditions appears less relevant. By affecting seasonal body mass dynamics, climate change may have consequences for life history and population dynamics of mountain herbivores, for example via earlier access of young males to reproduction.

A cradle-to-customer life cycle assessment case study of UK vertical farming

Global population rise, increased rural to urban migration, climate change and conflict have placed strain on global trade and food supply chains. Vertical farming (VF) is a relatively novel method for cultivating many fresh fruits and vegetables, and often is claimed to have lower environmental impacts than field cultivation. However, to date there are few studies utilising primary data which have evaluated the environmental impact VF may have. This study utilised Life Cycle Assessment (LCA) to evaluate the environmental impact of lettuce production in a commercial vertical farm in the UK. This was compared with data from the literature on the impacts of lettuce in field cultivation. Scenarios were also examined to evaluate the impact of VF systems with varying electricity sources, and waste, water and nutrient management options. The VF was found to have a similar or lower Climate Change impact than field cultivation, depending on energy source used. VF had a slightly higher environmental impact than field cultivation in some other environmental impact categories such as freshwater eutrophication potential and acidification potential. Electricity demand and the medium used for ‘plugs’ in the VF were found to be the main hotspots of the system. The results of this study provide insights on the environmental impact and resource efficiency of VF, feasibility for larger scale deployment, and provide further empirical evidence to support the claims made previously in the literature.

Digital infrastructure construction and regional mineral resource dependence in China: Heterogeneous characteristics and transmission mechanisms from mining industry

The emergence of the digital economy has challenged many of the theories of traditional environmental resource economics. As an emerging production factor, data have a significant impact and substitutability with digital technology on fossil energy utilization, which also makes the impact of digital infrastructure construction (DIG) on the allocation of mineral resources easily underestimated. This study is based on China's DIG and explores its impact on regional mineral resource dependence (NRD) in 30 provinces of China. We find that, with a 1% increase in DIG, NRD declines by 7.6%, with a lag effect between the two. The analysis of heterogeneous characteristics revealed the heterogeneous effects and dissimilation roles of DIG's effect on NRD. In terms of heterogeneous effects, in regions with high levels of resource endowment and low digital-economy contributions, DIG's empowering effects were more obvious. In terms of dissimilation roles, the facility foundation has played a more prominent role than digital access. We also find that, enhancing resource allocation efficiency, innovation output efficiency, and energy utilization efficiency can mediate the effects of DIG on NRD. Our findings can offer policy insights for reducing NRD to promote high-quality DIG, achieving differentiated digital empowerment patterns, and building multichannel resource reduction paths. This work also has reference value for green transformation in other developing countries and resource-based industries under the 2030 sustainable development goals.

Shallow tillage mitigates plant competition by increasing diversity and altering plant community assembly process.

Understanding how human activities affect biodiversity is needed to inform systemic policies and targets for achieving sustainable development goals. Shallow tillage to remove Artemisia ordosica is commonly conducted in the Mu Us Desert. However, the impacts of shallow tillage on plant community species diversity, phylogenetic structure, and community assembly processes remain poorly understood. This study explores the effects of shallow tillage on species diversity including three a-diversity and two b-diversity indicators, as well as phylogenetic structure [phylogenetic diversity (PD), net relatedness index (NRI), and nearest taxon index (NTI)]. Additionally, this research analyzes the effects of shallow tillage on the community assembly process. The results showed that the a-diversity index, b-diversity index, and PD of the shallow tillage (ST) communities were significantly higher than those of the non-shallow tillage (NT) communities, and the phylogenetic structures of both the ST and NT communities tended to be differentiated, with competitive exclusion being the main mechanism of plant assembly. However, shallow tillage increased the relative importance of the stochastic processes dominated by dispersal limitation, mitigating plant competition in the communities. This conclusion was supported by the Raup-Crick difference index-based analysis. Therefore, for the ecological restoration of the Mu Us Desert, species with adaptability and low niche overlap should be selected to increase the utilization efficiency of the environmental resources. The results of this study provide a foundation for policy development for ecosystem management and restoration in the Mu Us Desert.

Mathematical analysis of a non‐convex optimal control problem for age‐structured mosquito populations

We present a rigorous mathematical analysis of a non‐convex optimal control problem for mosquito populations. The nonlinear model for the dynamics of the mosquito population takes in consideration the iterations among the immature (aquatic) subpopulation, the adult winged subpopulation, and the environment resources; the immature subpopulation is assumed to be age‐structured. Moreover, the action of certain control mechanisms on these subpopulations is also taken in account. The cost functional to be minimized is non‐convex. The proof of the existence of an optimal control is done by using fixed point arguments and a special minimizing sequence obtained with the help of Ekeland's variational principle.

Study on spatio-temporal evolution of ecosystem services, spatio-temporal pattern of tradeoff/synergy relationship and its driving factors in Shendong mining area

Objectives: The game between socio-economic development and ecological development has always been the core issue in coal areas, but the internal mechanism of tradeoff and cooperative dynamic change of ecosystem services in mining areas under long-term mineral resources development is still lacking in in-depth research.Methods: Therefore, taking Shendong mining area as an example, this study used InVEST model to evaluate the changes of four major ecosystem service functions in Shendong mining area from 1990 to 2020, namely, water yield (WY), net primary productivity (NPP), soil conservation (SC) and habitat quality (HQ). Meanwhile, correlation analysis was used to explore the trade-off and synergistic relationship among these services. On this basis, the coupling effect between the four ecosystem services is further discussed by using the constraint line method. Finally, the key drivers of ecosystem service trade-offs/synergies in the region are explored by using geodetectors and the explanations of each influence factor for RMS errors are obtained.Results: The results show that 1) from 1990 to 2020, the water yield and soil retention in the mining area decrease first and then increase, and the net primary productivity and habitat quality increase slowly, mainly in the southeast of the mining area. 2) In terms of constraint relationship, all the four ecosystem services showed hump-like constraint relationship, that is, there was obvious constraint threshold effect. 3) In the Shendong mining area, the synergistic relationship is the dominant relationship between ecosystem services, and the tradeoff effect mainly occurs between water yield and habitat quality. 4) In terms of the driving mechanism of tradeoff/synergy, land use type, temperature, and rainfall are the main factors that cause the spatial differentiation of tradeoff synergy intensity among ecosystem services in Shendong mining area.Conclusions: The results of this study provide a scientific basis for the improvement of ecological environment and sustainable utilization of mineral resources under long-term exploitation.

Challenges and way forward in the handling and disposal of battery waste: Towards sustainable practices

<p>The management and disposal of battery waste, particularly lead-acid batteries, present numerous challenges that must be addressed to ensure environmental protection, public health, and sustainable resource management. This thesis examines the multifaceted nature of these challenges and explores potential solutions for sustainable battery management. Drawing on insights from prior research, field observations, stakeholder interviews, and literature reviews, the study synthesizes existing knowledge to inform strategies for mitigating the environmental, safety, and economic impacts associated with battery waste. The current scenario on battery waste management highlights significant challenges, including environmental pollution, health risks, safety hazards, recycling challenges, regulatory compliance issues, technological limitations, infrastructure constraints, and the need for public awareness and education. Countermeasures to address these challenges encompass regulatory interventions, technological innovations, infrastructure development, capacity building, and public engagement initiatives. By integrating findings from diverse sources, this thesis aims to contribute to the existing knowledge base on battery waste management and propel strategies for sustainable resource management.<strong></strong></p>

Comprehensive recovery of valuable metals from spent LiCoO2 cathode material by a method of NH4HSO4 roasting- (NH₄)₂S leaching

With the retirement of rechargeable lithium-ion batteries (LIBs) entering peak period, the recycling of LiCoO2 has become a hot topic. The spent LiCoO2 batteries are rich in carcinogenic metal Co and high-value metal Li, so they are needed to be recovered in time before causing serious environmental pollution and resource waste. Thus, a clean and efficient process is proposed for the comprehensive recovery of Li, Co, and Mn from the spent LiCoO2 cathode material. It is an integrated pyro-hydrometallurgical process, mainly consisting of sulfation roasting with NH4HSO4 and selective sulfurizing leaching with (NH4)2S solution. Using low melting point ammonium salt as roasting auxiliary, 99.7 %, 99.1 %, and 99.8 % of Li, Co, and Mn in the spent LiCoO2 powder can be converted into sulfate when roasting under 400 ℃ for 75 min. Then 99.5 % of Li in the sulfation roasting product can be selectively leached with an aqueous (NH4)2S solution, which is also a precipitator for Co, Mn, and impurity Al. In addition, 96.4 % of Co and 96.0 % of Mn in the sulfurized precipitate can be separated with impurity elements Al and C via oxidation roasting–water leaching process. Compared to traditional recycling, this method can achieve a higher Li leaching rate at a low roasting temperature, and the recovery of Co and Mn can be realized without adding any acid/base reagents or impurity cations. More importantly, the circulation of NH3/NH4+ and S element in the recycling system has been taken into account, making it an environmental-friendly and economical process. In this study, the sulfation reduction roasting and selective sulfurizing leaching mechanisms were both revealed in details, and the behavior of the valuable elements was also elucidated.