Resources Environment and Sustainability最新文献

The industrial dynamics of vanadium was simulated using the integrated assessment model WORLD7. The vanadium market may see strongly increased demand in the near future, and a pertinent question is if the new demands can be met. The WORLD7 model was used to assess the risk for future supply shortages. The global presence of vanadium in geological deposits was found to be about 710 million ton of vanadium. The extractable part was estimated to be about 60–70 million ton of vanadium, the rest being technically or economically inaccessible. Vanadium extraction is dominated by secondary extraction from primary metal production. The simulations suggests that there will be physical scarcity under business-as-usual for vanadium in after 2040. The vanadium price increases after 2030 according to the simulations, as a response to the scarcity. The introduction of a large-scale use of vanadium in battery technologies in the near future would aggravate future scarcity, even with more efficient recycling. Large scale use of vanadium for batteries, may keep vanadium prices high and require enhanced recycling to counter the threat of physical shortage after 2030.

Cassava’s transformation into an industrial raw material necessitates new processing techniques that improve quality while lowering processing costs. Drying has been identified as a major bottleneck in the production of high-quality cassava flour (HQCF) and expansion of its industrial application in Sub-Sahara African. This has triggered efforts towards developing an energy-efficient flash dryer for cassava flour/starch production at a small scale. A scaled-up version of the prototype flash dryer installed at the International Center for Tropical Agriculture (CIAT), Cali, Colombia, was built at the Federal Institute of Industrial Research, Oshodi, (FIIRO), Lagos, Nigeria based on numerical modeling.​ Excel tools developed by the CGIAR (RTB) scientists were used to design the components and built using locally sourced materials. The automation system of the flash dryer allows for operational flexibility, increased energy efficiency and reduced cost. It features a longer drying tube (22.5 m), a compact and improved heat exchanger, a larger blower for higher air velocity, and a high air/product ratio, thereby optimizing the drying efficiency. The dryer was evaluated with mechanically dewatered cassava mash (wet cake) dried into high quality cassava flour at air temperature of 180 °C and velocity of 13 m/s. The initial moisture content of the wet cake was 47.06 % wb, which was reduced to 9.6 % wb of dried product. Using a capacity of 298.0 kg of wet cake per hour, an output of 186.34 kg of dried product was achieved, resulting in an energy efficiency of 80.8 % and specific energy consumption of 2570 kJ/kg product of final product and 4560 kJ/kg water of evaporated water. These results revealed that the dryer is efficient and suitable for small-scale enterprises. Its use can reduce the production costs and expand the global market opportunity for cassava flour.

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Due to the lack of agreement on affiliation format between authors and the owner of the journal, this article has been retracted at the request of all authors, the Editors-in-Chief and the owner of the journal.

This study investigated the effects of soil amendment on potato yield and incidences of bacterial wilt caused by Ralstonia solanacearum that can cause up to 80% yield loss in potato. The research was conducted at four research stations in Malawi during the 2020/21 and 2021/22 growing seasons, using a randomized complete block design (RCBD) with six treatments: lime, four Calciprill rates (CALC25%, CALC50%, CALC100%, and CALC150%), and NPK fertilizer (control). Data on soil properties, bacterial wilt incidence, and potato tuber yield were collected and analyzed using R programming. Soil fertility was found to be low, with a pH range of 4.4–6.05. Control resulted to significantly higher incidences of bacterial wilt at Kandiyani during 2020/21 (63.6%) and 2021/22 (34.6%) and at Lunyangwa during 2021/22 (20.4%) while lime and all levels of Calciprill led to relative incidence reduction (4%–89%) across sites and season, except CALC25% at Bembeke. Marketable yield showed interaction between amendments and season at Bvumbwe (p = 0.04), highest being 10.02 tha⁻¹ in CALC150% during 2020/21 while non-marketable yield showed interaction at Lunyangwa (p = 0.02) highest being 3.9 tha⁻¹ recorded in CALC150% during 2021/22. A significant negative correlation between bacterial wilt incidences and yield at all sites except Bembeke highlighted the importance of controlling bacterial wilt for yield improvement. The findings suggest that soil amendment through liming is an effective and sustainable approach for managing bacterial wilt and increasing potato yields. Further research on-farm conditions required to ensure the applicability of the findings for different sites.

Anaerobic digestion (AD) is an effective method for treating organic waste. However, the performance of anaerobic reactors needs to be improved and comprehensively analyzed. This study proposed a ternary co-feedstock strategy for thermophilic anaerobic co-digestion of tomato plant residue, cattle manure, and food waste. The effects of changing the feedstock composition, feedstock-to-inoculum ratio, and total solids (TS) content were investigated. Among the tested mixtures, a ternary mixture of 60% tomato plant residue, 20% cattle manure, and 20% food waste with a feedstock-to-inoculum ratio of 0.7 gave the highest cumulative biogas (3.230 L), methane yield (2.575 L), methane content (79.71%), co-digestion performance index (1.65) and volatile solids (VS) removal rate (60.59%). Changing the feedstocks compositions caused changes in the specific biogas yield and specific methane yield. In tests with TS contents of 5%, 10%, 15%, and 20%, a higher TS content increased biogas and methane production because of increases in the amount of the biodegradable fraction in the reactor. However, there was a risk of volatile fatty acid overloading and a decrease in the VS removal rate because of inefficient decomposition of the high total solids content by microbes in the inoculum.

Extreme precipitation events can cause geomorphic adjustments in the riverscapes. As a result of the increase in severity and frequency of these events in climate change scenarios, riverscapes may become more sensitive to the geoforms sculpting processes. Consequently, communities in the river valleys may be adversely affected, worsening socio-environmental problems arising from these places’ occupation. This work investigates the relationship between events classified as heavy rainfall and persistent rainfall and geomorphic adjustments in the riverscape. A section of the Itapocu River in southern Brazil between latitudes 26°25’S and 26°32’S was used as a case study. Extreme events recorded in pluviometers’ historical series located around the study area were selected and characterized. These events occurred between 01/30/2019 and 04/15/2019; 11/15/2020 and 12/30/2020; 02/23/2021 and 03/10/2021. The geomorphic adjustments were identified by selecting Sentinel-2 orbital imagery. The satellite images were applied in the river valley geoforms vectorization and correlation among transverse and longitudinal sections to the river valley. The analysis of fluvial sensitivity went through the adjustments’ significance evaluation by the Wilcoxon Signed Rank Test. The results indicated that the river presented adjustments related to extreme precipitation events. These adjustments were identified as channel migration, channel expansion, channel narrowing, river bar expansion, and river bar narrowing. However, only channel migration, channel expansion, and channel narrowing were significant. In 2019, 82.03% of the river was significantly affected by the events, while in 2020 and 2021, events impacted 57.67% and 64.72% of the river, respectively.

Commodity plastics such as polyethylene (PE), polypropylene (PP) and polyethylene terephthalate (PET) are some of the common plastic wastes found in municipal wastes. Lack of technology, resources, coherent programs, policies, mismanagement and incomplete processing of these plastics, results in these plastics mostly ending up in landfills. Adopting a qualitative research approach, the paper reviewed PE, PP and PET recycling waste management processes from selected developed and developing countries. It was found that chemical recycling in terms of catalytic cracking followed by pyrolysis technologies are more suitable for producing higher liquid oils whiles gasification improves fuel gas yield. Given that mechanical recycling requires less capital and resources, it is a more suitable waste management option for plastic products in developing countries. In cases where there are complex separation issues, incineration for energy recovery is appropriate but it should be used with end-of-pipe treatment solutions to mitigate against the environmental impact of incineration. The paper further highlights various opportunities and challenges involved with PE, PP and PET plastic waste treatment pathway, the appropriate yields obtained for each technique and where adaptation can be made.

While economics has long recognized concern for others (e.g. altruism and bequest motives), explicit inclusion of social network metrics in non market valuation models is relatively recent. Social network effects on willingness to pay can propagate through the entire network and bias willingness to pay (WTP) estimates. However, social networks are complex systems of relationships between individuals, and measuring them can be difficult. We explored the potential for egocentric social network (ESN) measures to help explain variations in preference for the status quo. Using simulated random networks, we demonstrate that respondents more likely to choose an alternative to the status quo are part of more dense ESNs. A strong influence of an attitude toward the impact of economic development on the environmental goods and services is consistent with network structure and preference for environmental improvements being jointly determined.

Agriculture is of great importance in all societies, serving as the fundamental basis for producing food and ensuring the survival of human populations. The process of agricultural production and the associated logistical elements face numerous difficulties, which are further intensified by the worldwide water scarcity resulting from climate change. Nevertheless, the existing body of literature has not sufficiently addressed the consequences of water scarcity on agri-food supply chains. To bridge this research gap and contribute to mitigating the global water crisis induced by climate change, this study proposes a hybrid model that combines optimized neural networks based on meta-heuristic algorithms and mathematical optimization for a sustainable agricultural supply chain. The proposed model integrates particle swarm optimization (PSO) for feature selection and a hybrid convolutional neural network (CNN)-gated recurrent unit (GRU) with a genetic algorithm (GA) optimized structure to predict water consumption. Leveraging the model’s results, a multi-objective sustainable agriculture supply chain model is developed to optimize supply chain profitability while simultaneously addressing environmental pollutants, production waste, food waste, water usage, and manufacturing costs and time. To evaluate the effectiveness of the proposed approach, a real case study in Iran is employed, providing both theoretical and practical insights into the design of agriculture supply chain optimization that incorporates sustainability factors and effectively tackles the growing challenge of water scarcity. The findings of this study hold implications for managers and policymakers in countries where the importance of sustainability is growing. By integrating advanced optimization techniques and predictive models, this research offers a novel framework for enhancing the sustainability of agricultural supply chains and addressing the pressing issues of water scarcity induced by climate change.