Sustainable Management Strategies Research Articles

Analyzing non-revenue water dynamics in Rwanda: leveraging machine learning predictive modeling for comprehensive insights and mitigation strategies

ABSTRACT This study investigated non-revenue water (NRW) dynamics in Rwanda from 1 July 2014 to 30 June 2023, utilizing panel data and cross-sectional datasets. It aimed to assess progress toward achieving the government's 25% NRW reduction target. Through panel data analysis and machine learning models, it examined water supply variations, NRW levels, and associated risks across fiscal years and regions. The observed average NRW of 41.24% underscores the need for targeted interventions to meet the set target. Regional disparities, exemplified by Kigali City's water network's 38.61% average NRW compared to Nyagatare's 55.31%, emphasize the importance of tailored strategies. Machine learning models indicated low and inconsistent progress across networks. Notably, no single water supply managed to meet the target in more than 20% of the 36 quarters studied. Comparison with existing literature highlighted excessive NRW in Rwanda, aligning with global trends. Achieving the 25% NRW target requires region-specific approaches, necessitating infrastructure improvements, leak detection, and capacity building. The positive correlation between water loss risk and household access to improved water sources accentuated the complexity in NRW reduction efforts. This study contributes to understanding NRW dynamics and informs sustainable water management strategies tailored to Rwanda's context.

Help us Deal with Water Crisis! Solving Water Crisis to Save Lives.

Water scarcity remains a critical global challenge, prompting the exploration of innovative strategies for sustainable water management. This study investigates the dual potential of rainwater harvesting and ocean water purification as solutions to address water scarcity. Through a comprehensive review of literature and case studies, this research examines the efficacy, challenges, and implementation strategies of both approaches across diverse contexts. The findings underscore the capacity of rainwater harvesting to augment local water supplies and reduce dependence on traditional sources, while ocean water purification offers a promising avenue for expanding freshwater resources. Key factors influencing success, including technological advancements, policy support, and community engagement, are identified and analyzed. Moreover, the study explores the environmental, economic, and social implications of these approaches, emphasizing their role in water conservation, climate change resilience, and sustainable development. Practical recommendations are offered for policymakers, practitioners, and communities to leverage rainwater harvesting and ocean water purification as complementary strategies for addressing water scarcity and advancing water security globally.

Brown midrib (BMR) and plant age impact fall armyworm (Spodoptera frugiperda) growth and development in sorghum-sudangrass (Sorghum x drummondii)

Economic losses from insect herbivory in agroecosystems has driven the development of integrated pest management strategies that reduce pest incidence and damage; however, traditional chemicals-based control is either being complemented or substituted with sustainable and integrated methods. Major sustainable pest management strategies revolve around improving host plant resistance, and one of these traits of interest is Brown midrib (BMR). Originally developed to increase nutritional value and ease of digestion for animal agriculture, BMR is a recessive plant gene usually found in annual grasses, including sorghum and sorghum-sudangrass hybrids. In sorghum-sudangrass, BMR expressed plants have lower amounts of lignin, which produces a less fibrous, more digestible crop, with possible implications for plant defense against herbivores- an area currently unexplored. Fall Armyworm (FAW; Spodoptera frugiperda) is a ruinous pest posing immense threat for sorghum producers by severely defoliating crops and being present in every plant stage. Using FAW, we tested the effect of seed treatment, BMR, and plant age on FAW growth, development, and plant defense responses in sorghum-sudangrass. Our results show that seed treatment did not affect growth or development, or herbivory. However, presence of BMR significantly reduced pupal mass relative to its non-BMR counterpart, alongside a significant reduction in adult mass. We also found that plant age was a major factor as FAW gained significantly less mass, had longer pupation times, and had lower pupal mass on the oldest plant stage explored, 60-days, compared to younger plants. These findings collectively show that pest management strategies should consider plant age, and that the effects of BMR on plant defenses should also be studied.

Disentangling the impact of nested sources of variability on species growth processes: A mixture of multilevel mixed model approach.

SummaryThe understanding of tree growth processes is crucial for promoting sustainable forest management strategies. This is a challenging task in highly biodiverse ecosystems where many tree species are observed on very few individuals and the small sample sizes hinder a good fit of species‐specific models. We propose the use of finite mixture of random coefficient regression models with multilevel nested random effects to infer guild specific fixed and random effects while evaluating the relative importance of the nested sources of variability on goodness‐of‐fit. This approach extends finite mixture of linear mixed model used for longitudinal or single group structured data contexts. A dedicated expectation–maximisation algorithm is introduced for parameter estimation. Simulations are performed for the evaluation of the misspecification of nested‐grouping structures. This work has been motivated by data collected biennially in Central African rainforests from 1986 to 2010. We show the accuracy of the proposed approach in successfully reproducing individual growth processes and classifying tree species into well‐differentiated clusters with clear ecological interpretations. Moreover, results confirm that interindividual variability appears as the most important factor to explain tropical tree species growth process variability from Central Africa forests.

Optimizing ELD in power systems applying GWO: A Practical Approach

Addressing the Economic load Dispatch (ELD) Problem in power systems is crucial for minimizing generation cost and transmission losses while meeting the load demand. This research explores the application of Grey Wolf Optimization (GWO) to solve the ELD problem, leveraging ‘GWO’s inspiration from grey wolf social behavior. Through simulation, ‘GWO’s superior convergence speed and solution quality compared to traditional techniques is demonstrated. The finding highlights ‘GWO’s effectiveness in enhancing the economic and operational efficiency of power systems, offering promising avenues for sustainable energy management strategies.

Comprehensive assessment of water and sediment quality to support sustainable management practices and mitigate potential risks of trace metal pollution in the Johor River Basin, South Peninsular Malaysia

Human activities have caused concerns over the contamination of trace elements in aquatic systems due to their toxicity, long-lasting nature, and ability to accumulate in living organisms. This study evaluated the spatial pattern, environmental hazard, and potential health hazard of 13 trace metals in water and sediment samples collected from the Johor River basin using multivariate statistical techniques in order to identify the impact of both natural and human-related factors on the presence of trace metals in the area. The increased levels of metals in Station S1 indicated a significant impact from municipal, domestic, and industrial waste. The Geo-accumulation Index (Igeo) values for pollution and ecological indices in the sediment of the Johor River Basin ranged from -9.44 to 6.27. The Pollution Load Index (PLI) values ranged from 0.05 to 0.18, and the Potential Ecological Risk Assessment (RI) values ranged from 2.15 to 11.18. These results indicate that the sediments in the Johor River Basin have a low risk of contamination from trace metals. The water's hazard quotient (HQ) had an average value of 0.0001, while the hazard index (HI) had an average value of 0.0003. It is important to increase stakeholders' understanding and concerns regarding the potential long-term human health and ecological implications associated with trace metals in Johor River water. The results of this study offer essential initial information for government entities to implement sustainable management strategies, reducing the likelihood of future trace metal contamination issues in the Johor River basin and similar regions.

Occurrence and Ecotoxicological Impacts of Polybrominated Diphenyl Ethers (PBDEs) in Electronic Waste (E-Waste) in Africa: Options for Sustainable and Eco-Friendly Management Strategies

Polybrominated diphenyl ethers (PBDEs) are persistent contaminants used as flame retardants in electronic products. PBDEs are contaminants of concern due to leaching and recalcitrance conferred by the stable and hydrophobic bromide residues. The near absence of legislatures and conscious initiatives to tackle the challenges of PBDEs in Africa has allowed for the indiscriminate use and consequent environmental degradation. Presently, the incidence, ecotoxicity, and remediation of PBDEs in Africa are poorly elucidated. Here, we present a position on the level of contamination, ecotoxicity, and management strategies for PBDEs with regard to Africa. Our review shows that Africa is inundated with PBDEs from the proliferation of e-waste due to factors like the increasing growth in the IT sector worsened by the procurement of second-hand gadgets. An evaluation of the fate of PBDEs in the African environment reveals that the environment is adequately contaminated, although reported in only a few countries like Nigeria and Ghana. Ultrasound-assisted extraction, microwave-assisted extraction, and Soxhlet extraction coupled with specific chromatographic techniques are used in the detection and quantification of PBDEs. Enormous exposure pathways in humans were highlighted with health implications. In terms of the removal of PBDEs, we found a gap in efforts in this direction, as not much success has been reported in Africa. However, we outline eco-friendly methods used elsewhere, including microbial degradation, zerovalent iron, supercritical fluid, and reduce, reuse, recycle, and recovery methods. The need for Africa to make and implement legislatures against PBDEs holds the key to reduced effect on the continent.

Impacts and implications of anthropogenic activities on mangrove forests: A review

The purpose of this paper is to review and evaluate published literature on the causes, impacts, implications and mitigation strategies of anthropogenic activities on mangrove forests. A systematic method was utilized to access research works of literature on “Impacts and implications of anthropogenic activities on mangrove forests”. A total of fifty-three (53) research papers published between the years 1975 to 2024 was accumulated and used for this review. A subjective approach was used to select the topics: impact and implications of anthropogenic activities on mangrove forests. In this paper, five (5) roles of mangroves were assessed and presented. Anthropogenic activities that threaten mangrove forests such as land conversion, mining and logging activities and household and industrial activities were also evaluated. Further, four (4) detrimental anthropogenic activities and the potential impacts they have on natural mangrove forests and the ecosystems they thrive in was also reported on. In addition, this paper reviewed some mitigation strategies for sustainable management and conservation of our mangroves, their ecosystems and the coastlines. The published works of literature established that reduced mangrove forests, altered mangrove composition, unequal species abundance, mass mangrove mortality, pollution in mangrove areas, rising sea levels, global climate change and coastal erosion or abrasion are all effects of anthropogenic activity that have a negative impact on mangrove forests and the ecosystems. This review highlights the fact that more studies on the impact and implications of anthropogenic activities on mangroves should be done in neotropical countries since there are paucity of such information on research and published data in these biodiversity rich regions.

Abundance and Dispersion Indices of Helicoverpa armigera (Lepidoptera: Noctuidae) on Tomato Plant in Nigeria

Helicoverpa armigera is among the major insect pests that pose a threat to tomato production in Nigeria with an insufficient understanding of its population parameters, and available environmentally friendly control materials which are essential for the development of reliable and sustainable management strategies that can minimize the frequent use of synthetic pesticides; which are hazardous to the environment, non-target organism, and humans. The present study was conducted with the objectives of establishing population abundance and dispersion of H. armigera. Surveys were conducted in the savannah agroecological zone of Nigeria through fortnightly field visits to tomato farms from July to September 2019 (rainy season), and month of December 2019 to March 2020 (dry season), making a total of seven (7) and Nine (9) visits respectively. Ten plants were randomly selected and tagged from each farm, for observation of the presence of H. armigera larvae on the upper and lower parts early in the morning (6:00-7:30 am) on all sampling. Numbers found on each plant were counted and recorded with dates. Data obtained were subjected to analysis of variance and the least significant difference (LSD) at 0.05% level of probability was used to separate significant means. Data were further used in calculating the various dispersion indices. The result indicates that H. armigera was higher at 8 weeks after planting and aggregated on the upper part of the plant with a higher population in the dry season. Abundance and dispersion indices of H. armigera on tomato plants reported in this study will provide for appropriate decision-making in designing eco-friendly management of the pest.

Local Community Attitude towards Forest-Based Ecotourism Development in Arbegona and Nensebo Woredas, Southern Ethiopia

Understanding local community awareness and attitude towards forest-based ecotourism welfare is an important input for policymakers to develop and implement sustainable forest resource management strategies. However, the local community’s awareness and attitude towards forest-based ecotourism development have been poorly assessed and documented in remote areas. To this end, the present study assessed the local community’s awareness and attitude in Arbegona and Nensebo woredas’ forests, southern Ethiopia, towards ecotourism development. Household and key informant interviews and focus group discussions were used to collect data. Results indicated that more than half (57.9%) of the respondents expressed a negative attitude towards forest-based ecotourism development. The educational status of the respondents, their age, presence of conservation measures, source of energy for household consumption, and biophysical and socio-cultural variations in the study sites are significantly associated with local communities’ attitudes that have been exhibited towards the development of ecotourism and conservation of forest resources. Creating awareness through persuasion and communication of new and well-suited information, promoting alternative livelihood options, encouraging local benefits from the conservation of forest resources, and compensating costs induced by wild animals can minimise negative attitudes, thereby contributing to the enhancement of local communities’ positive attitudes towards forest resource conservation.

First report of Telenomus remus Nixon (Hymenoptera: Scelionidae) on Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) in Egypt

BackgroundThe polyphagous alien invasive pest, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), invaded Africa and has so far spread across the continent, causing devastating impacts on maize production. In Egypt, the management of the pest by maize growers has been characterized by the application of broad-spectrum synthetic chemical insecticides, a strategy which is associated with various detrimental effects on the environment and human health. To mitigate the overreliance and excessive use of those synthetic chemicals, biological control using egg parasitoids species provides an ecologically friendly and sustainable management strategy. In that regard, this study had the objective of identifying the natural existing egg parasitoids, which could be effectively used in augmentative biocontrol of the pest in Egypt.ResultsFor the first time in Egypt, natural occurrence and parasitism of Telenomus remus Nixon, 1937 (Hymenoptera: Scelionidae) on S. frugiperda egg masses was recorded. Infested maize farms in Qena Governorate, Egypt, were surveyed, and S. frugiperda egg masses were collected and incubated in the laboratory. Emerging parasitoids’ wasps were grouped based on their morphological similarities. Natural parasitism of the egg parasitoids (Telenomus sp.) was computed from the parasitized field collected egg masses. In addition, to confirm the laboratory parasitism and suitability of the parasitoid, Telenomus sp. to develop on S. frugiperda, the parasitoid was reared on S. frugiperda egg masses for three generations under laboratory conditions. Moreover, both morphological and molecular identifications were conducted. The recovered parasitoid samples from the field S. frugiperda egg masses were Telenomus remus (Nixon) (Hymenoptera: Scelionidae). Moreover, the average field parasitism level by T. remus on S. frugiperda was 15.9%, while under laboratory conditions, the parasitism was 63.5%.ConclusionsThe natural occurrence of T. remus in Egypt and its association with S. frugiperda is an important finding upon which augmentative biocontrol strategy can be leveraged on to sustainably manage the pest populations.

Synthesis of organic-inorganic hybrid nanocomposites modified by catalase-like catalytic sites for the controlling of kiwifruit bacterial canker.

Kiwifruit bacterial canker, caused by Pseudomonas syringae pv. Actinidiae (Psa), is one of the most important diseases in kiwifruit, creating huge economic losses to kiwifruit-growing countries around the world. Metal-based nanomaterials offer a promising alternative strategy to combat plant diseases induced by bacterial infection. However, it is still challenging to design highly active nanomaterials for controlling kiwifruit bacterial canker. Here, a novel multifunctional nanocomposite (ZnO@PDA-Mn) is designed that integrates the antibacterial activity of zinc oxide nanoparticles (ZnO NPs) with the plant reactive oxygen species scavenging ability of catalase (CAT) enzyme-like active sites through introducing manganese modified polydopamine (PDA) coating. The results reveal that ZnO@PDA-Mn nanocomposites can efficiently catalyze the conversion of H2O2 to O2 and H2O to achieve excellent CAT-like activity. In vitro experiments demonstrate that ZnO@PDA-Mn nanocomposites maintain the antibacterial activity of ZnO NPs and induce significant damage to bacterial cell membranes. Importantly, ZnO@PDA-Mn nanocomposites display outstanding curative and protective efficiencies of 47.7% and 53.8% at a dose of 200 μg mL-1 against Psa in vivo, which are superior to those of zinc thiozole (20.6% and 8.8%) and ZnO (38.7% and 33.8%). The nanocomposites offer improved in vivo control efficacy through direct bactericidal effects and decreasing oxidative damage in plants induced by bacterial infection. Our research underscores the potential of nanocomposites containing CAT-like active sites in plant protection, offering a promising strategy for sustainable disease management in agriculture.

Assessing the Influence of Soil Physical Properties on the Puddling Quality: A Comprehensive Review

Puddling is a crucial step in rice cultivation, extensively practiced by farmers in Asia for its role in softening soil, aiding in transplanting, and enhancing water and nutrient management. However, the alteration of soil properties by puddling raises concerns about its long-term sustainability. This comprehensive review systematically examines the impact of puddling on soil parameters such as soil texture, bulk density, penetration resistance, hydraulic conductivity, puddling index, and percolation rate. By synthesizing existing literature, the review aims to inform sustainable agricultural practices and effective soil management strategies amidst escalating global concerns. The complexities of puddling's influence on soil structure underscore the need to consider variables like soil texture and aggregate stability. Sustainable practices such as organic manure application offer potential solutions to address puddling-induced compaction, thereby enhancing soil quality and rice production efficiency. Optimizing tillage methods and improving hydraulic conductivity are essential components of effective soil management strategies for sustainable rice cultivation. Additionally, assessing puddling quality through indices like the puddling index and optimizing percolation rates are vital steps toward improving water management and overall productivity in rice farming.

Non-target effects of neurotoxic insecticides on Ganaspis cf. brasiliensis, a classical biological control agent of the spotted wing Drosophila

BackgroundThe spotted wing drosophila, Drosophila suzukii, is an invasive pest causing significant economic losses worldwide. Current pest control strategies mainly rely on insecticides, which negatively impact fruit marketability and the sustainability of integrated pest management (IPM) programs. In addition, pesticides can have dramatic consequences on non-target species when persisting in the environment at low concentrations after field applications. In this context, chemical control can strongly interfere with the releases of the G1 strain of the Asian larval parasitoid Ganaspis cf. brasiliensis, which is currently the adopted classical biological control agent to manage D. suzukii infestations worldwide.MethodsProbit analysis was used to assess the baseline toxicity of acetamiprid, cyazypyr, lambda-cyhalothrin, phosmet, and spinosad on G1 G. cf. brasiliensis adults through residual contact exposure in the laboratory. Then, adult parasitoids were exposed to insecticide low Lethal Concentrations (LC5 and LC30) and their mortality was checked daily to assess the survival of treated wasps.ResultsLambda-cyhalothrin showed the highest toxicity on the parasitoid with a LC50 of 1.38 × 10–3 g active ingredient (a.i.) /L, while cyazypyr seemed the safer active ingredient with an estimated LC50 of 0.20 g a.i./L without affecting parasitoids at sublethal doses. Spinosad and phosmet significantly reduced wasp survival at both LC30 and LC5, while lambda-cyhalothrin and acetamiprid affected parasitoid lifespan only at LC30. Spinosad, lambda-cyhalothrin and phosmet LC30 caused the major survival reductions, followed by acetamiprid LC30. The least significant reduction in parasitoid survival was 21.6% by spinosad LC5.ConclusionsOverall, this study highlighted the importance of carefully selecting insecticides to minimize adverse effects on non-target organisms. In particular, cyazypyr was the most promising candidate to integrate inoculative biological control with chemical treatments. By contrast, the application of phosmet, spinosad and lambda-cyhalothrin should be avoided alongside parasitoid field releases. Although acetamiprid is less used against D. suzukii in the field than the other tested molecules, it should be used with caution due to its sublethal toxicity on the parasitoid. These results provide the first evidence of G. cf. brasiliensis susceptibility to insecticides in order to promote sustainable and efficient pest management strategies.

Adaptive silviculture for climate change in the Great Lakes- St. Lawrence Forest Region of Canada: Background and design of a long-term experiment

We present the implementation of the Adaptive Silviculture for Climate Change (ASCC) initiative at the Petawawa Research Forest (PRF) in Ontario, Canada. The study addresses the urgent need for adaptive forest management strategies in response to climate change by examining silvicultural treatments aimed at mitigating its impacts on forest ecosystems. It addresses the complex interplay between climate change projections, regional climate characteristics, and forest management practices for pine dominated forests in the Great Lakes-St. Lawrence Forest region of Canada, underscoring the importance of adaptive approaches in sustaining forest ecosystems. We outline the design and objectives of five distinct treatments—control, business-as-usual, resistance, resilience, and transition—implemented over 4 replicate blocks on a 212-ha area at the PRF. We provide detailed descriptions of each treatment’s management objectives, desired future conditions, and silvicultural strategies. We conclude by summarizing planned research efforts, including seedling survival assessments, phenological monitoring, and measuring treatment impact on fuel loads. By addressing the challenges and opportunities of climate change as part of an international research network, this research will contribute to a deeper understanding of forest ecosystem responses to climate change and inform adaptive management strategies for sustainable forest management.

Optimizing Pathogen Control through Mixed Cocoa–Plantain Agroecosystems in the Ecuadorian Coastal Region

Mixed production systems play a vital role in the economic sustainability and ecological balance of agroecosystems. Cocoa and plantain are key crops in Ecuador but face phytosanitary challenges, like witches’ broom and black sigatoka diseases, especially when cultivated under monocropping systems. Combining habitat manipulation with adaptive pathogen management (APM) strategies can mitigate these challenges, but their efficacy in mixed cropping systems remains unclear. This study investigates disease and pest incidence in mixed cocoa–plantain systems during the establishment phase, focusing on the impact of spatial arrangements. Mixed agroecosystems showed a lower witches’ broom incidence in cocoa than monocultures. Whereas, in plantain, there was a consistent black sigatoka incidence across spatial arrangements but a lower infection rate per leaf within mixed systems. We found varied nematode populations with monocultures hosting the highest root damage due to phytoparasitic nematodes. Weevil populations were also influenced by spatial arrangements with monocultures among the highest. Overall, mixed agroecosystems influence disease and pest incidence, potentially hindering pathogen spread. Plantain–cocoa associations reduce disease incidence in cocoa but may not affect the overall incidence of black sigatoka in plantain, at least during the establishment phase. Continued monitoring is crucial for understanding the long-term impacts and microclimatic effects on pest populations that could offer sustainable pest management strategies, reducing the reliance on chemical pesticides.

Enhancing Broiler Weight Estimation through Gaussian Kernel Density Estimation Modeling

The management of individual weights in broiler farming is not only crucial for increasing farm income but also directly linked to the revenue growth of integrated broiler companies, necessitating prompt resolution. This paper proposes a model to estimate daily average broiler weights using time and weight data collected through scales. In the proposed model, a method of self-adjusting weights in the bandwidth calculation formula is employed, and the daily average weight representative value is estimated using KDE. The focus of this study is to contribute to the individual weight management of broilers by intensively researching daily fluctuations in average broiler weight. To address this, weight and time data are collected and preprocessed through scales. The Gaussian kernel density estimation model proposed in this paper aims to estimate the representative value of the daily average weight of a single broiler using statistical estimation methods, allowing for self-adjustment of bandwidth values. When applied to the dataset collected through scales, the proposed Gaussian kernel density estimation model with self-adjustable bandwidth values confirmed that the estimated daily weight did not deviate beyond the error range of ±50 g compared with the actual measured values. The next step of this study is to systematically understand the impact of the broiler environment on weight for sustainable management strategies for broiler demand, derive optimal rearing conditions for each farm by combining location and weight data, and develop a model for predicting daily average weight values. The ultimate goal is to develop an artificial intelligence model suitable for weight management systems by utilizing the estimated daily average weight of a single broiler even in the presence of error data collected from multiple weight measurements, enabling more efficient automatic measurement of broiler weight and supporting both farms and broiler demand.

Response of Species to the Impact of Climate Change in the Gum Arabic Belt, Sudan: A Case Study in Acacia senegal

Sustainable management strategies of trees are important for indigenous agroforestry plant species, such as Acacia. Senegal (A. Senegal), due to the impacts of rapid population growth, land use and climate change. The objective of this investigation was to predict the spatio-temporal distribution of A.senegal in the Gum Arabic belt in Sudan in current (1985–2000) and future climate scenarios (2021–2100). Bioclimatic data was used for modeling purposes utilizing Maxent, with the assessment of model precision conducted through the utilization of the Area Under the Curve (AUC) and shown a high goodness-of-it (AUC=0.905±0.003 ). Significant differences were shown in species distribution between current and future periods under selected Shared Socioeconomic Pathways (SSPs) of SSP2-4.5 and SSP5-8.5, climate scenario. Our findings indicated that the main predictors influence the distribution of the species were precipitation of wettest quarter and maximum temperature of warmest month. Under the current potential distribution (25.4%), it is projected that Acacia Senegal would expand 36.2%-87.7% (SSP2-4.5) and 38.9-42.5% (SSP5-8.5). It is expected that A.cacia Senegal will create new environments suitable for it due to expected climate changes. Hence, the research necessitates the formulation of a strategic plan aimed to rehabilitation plantations of Acacia senegal and cultivation these species within existing and prospective habitats conducive to their existence.

Microbial community structure and metabolic profile of anthropized freshwater tributary channels from La Plata River, Argentina, to develop sustainable remediation strategies.

Microbial communities from freshwater sediments are involved in biogeochemical cycles and they can be modified by physical and chemical changes in the environment. Linking the microbial community structure (MCS) with physicochemistry of freshwater courses allows a better understanding of its ecology and can be useful to assess the ecological impact generated by human activity. The MCS of tributary channels from La Plata River affected by oil refinery (C, D, and E) and one also by urban discharges (C) was studied. For this purpose, 16S rRNA metabarcoding analysis, in silico metagenome functional prediction, and the hydrocarbon degradation potential (in silico predictions of hydrocarbon-degrading genes and their quantification by qPCR) of the MCS were studied. Principal coordinate analysis revealed that the MCS was different between sites, and it was not structured by the hydrocarbon content. Site C showed physicochemical characteristics, bacterial taxa, and an in silico functional prediction related to fermentative/heterotrophic metabolism. Site D, despite having higher concentration of hydrocarbon, presented autotrophic, syntrophic, and methanogenic pathways commonly involved in natural processes in anoxic sediments. Site E showed and intermediate autotrophic/heterotrophic behavior. The hydrocarbon degradation potential showed no positive correlation between the hydrocarbon-degrading genes quantified and predicted. The results suggest that the hydrocarbon concentration in the sites was not enough selection pressure to structure the bacterial community composition. Understanding which is the variable that structures the bacterial community composition is essential for monitoring and designing of sustainable management strategies for contaminated freshwater ecosystems.

Effective cost management strategies in global supply chains

This review paper explores effective cost management strategies within global supply chains, highlighting the necessity for businesses to adapt and innovate in response to complex logistical operations, economic fluctuations, and geopolitical risks. It delves into strategic sourcing and procurement, inventory management techniques such as Just-In-Time (JIT) systems, logistics and transportation optimization, and the pivotal role of technology and automation in enhancing efficiency and reducing costs. The paper identifies gaps in current literature, particularly the need for more research on sustainable practices and risk management strategies. Recommendations for practical implementation are provided, emphasizing flexibility, resilience, and the importance of leveraging technology. Future research directions are suggested to further understand the dynamics of global supply chain cost management and the integration of sustainability practices. Keywords: Global Supply Chain, Cost Management, Strategic Sourcing, Inventory Management, Supply Chain Technology, Risk Management.