Variations In Environmental Parameters Research Articles

Groundwater Contamination: Study on the Distribution and Mobility of Metals and Metalloids in Soil and Rocks

This study investigates the distribution and mobility of metals and metalloids (M&Ms) in soils, rocks, and groundwater within the geologically complex southwestern region of Sicily. The study aims to highlight how natural sources, like rocks and soils, can release elements potentially harmful to human health. It underlines their dual role as both natural reservoirs and active sources of M&M release, driven by leaching processes influenced by physicochemical factors such as pH and redox potential (Eh). Lithological characteristics significantly influence the retention and release of elements, with clay-rich formations exhibiting higher immobilization capacity. However, environmental parameter variations can enhance element mobilization, increasing bioavailability and the risk of groundwater contamination. Water quality analyses reveal regulatory exceedances for As, B, Ni, and Be, underscoring potential health and ecological risks. Concurrently, microbiological investigations identify diverse microbial communities capable of altering the oxidative states of specific elements through oxidation and reduction processes, further influencing their mobility. This study underscores the importance of understanding natural sources of M&Ms and their interactions with geochemical and microbiological processes for effective environmental risk assessment. The findings provide a foundation for developing integrated and sustainable water resource management strategies to mitigate contamination risks and safeguard ecosystems and public health.

Antibiotic resistance genes (ARGs) in microorganisms and their indications for the nitrogen/sulfur cycle in the East China Sea sediments.

Antibiotic resistance genes (ARGs) are emerging environmental pollutants, posing an escalating threat to public health and environmental security worldwide. However, the relationship between ARGs and microbial communities in the environment, as well as their ecological effects on the microbe-mediated materials cycle remain unclear. In this study, we investigated the spatial distribution pattern, influence mechanism, relationship with microorganisms, and their effects on the elemental cycling of ARGs in East China Sea sediments. The results showed that temperature caused a latitudinal gradient in the distribution of ARGs. The sulfonamide and quinolone ARGs were characterized by a distribution pattern of "higher in the south and lower in the north" with a boundary of 29 °N, while tetracycline and macrolide ARGs have the opposite distribution patterns. The spatial variation of environmental parameters shaped the differences in microbial abundance and diversity. Sulfonamide and quinolone ARGs were greatly affected by temperature, intI1, microbial composition, and abundance, while tetracyclines and macrolides ARGs were mainly affected by microbial alpha diversity index and NO2-. ARGs and intI1 were synchronously significantly correlated with nitrogen and sulfur cycle functional genes, indicating that microorganisms with ARGs can integrate nitrogen and sulfur cycle functional genes through intI1, thereby promoting or inhibiting nitrogen and sulfur cycle. This study will provide an important scientific basis for exploring the pollution control and ecological risk assessment of ARGs in sediments.

Slower swimming promotes chemotactic encounters between bacteria and small phytoplankton

Chemotaxis enables marine bacteria to increase encounters with phytoplankton cells by reducing their search times, provided that bacteria detect noisy chemical gradients around phytoplankton. Gradient detection depends on bacterial phenotypes and phytoplankton size: large phytoplankton produce spatially extended but shallow gradients, whereas small phytoplankton produce steeper but spatially more confined gradients. To date, it has remained unclear how phytoplankton size and bacterial swimming speed affect bacteria's gradient detection ability and search times for phytoplankton. Here, we compute an upper bound on the increase in bacterial encounter rate with phytoplankton due to chemotaxis over random motility alone. We find that chemotaxis can substantially decrease search times for small phytoplankton, but this advantage is highly sensitive to variations in bacterial phenotypes or phytoplankton leakage rates. By contrast, chemotaxis toward large phytoplankton cells reduces the search time more modestly, but this benefit is more robust to variations in search or environmental parameters. Applying our findings to marine phytoplankton communities, we find that, in productive waters, chemotaxis toward phytoplankton smaller than 2 μm provides little to no benefit, but can decrease average search times for large phytoplankton (∼20 μm) from 2 wk to 2 d, an advantage that is robust to variations and favors bacteria with higher swimming speeds. By contrast, in oligotrophic waters, chemotaxis can reduce search times for picophytoplankton (∼1 μm) up to 10-fold, from a week to half a day, but only for bacteria with low swimming speeds and long sensory timescales. This asymmetry may promote the coexistence of diverse search phenotypes in marine bacterial populations.

Variation of Environmental Parameters during Drying of Tomato under Low Cost Multipurpose Greenhouse (MGH)

Variation of Environmental Parameters during Drying of Tomato under Low Cost Multipurpose Greenhouse (MGH)

Effect of Change in Physical Parameters in the Paddling Response of the Common Backswimmer (Notonecta glauca)

This study investigates the impact of varying environmental factors, specifically temperature, pH, and white light intensity, on the paddling response of the common backswimmer, Notonecta glauca Linnaeus 1758 (Hemiptera: Notonectidae). The normal paddling rate was established at approximately 31.6 flaps per minute (FPM) under controlled conditions of 30°C, pH 6.8, and 50% sunlight exposure. When exposed to increased pH levels, the paddling rate exhibited a significant increase, rising by nearly 75% compared to the normal rate. Conversely, a decrease in pH led to an even greater enhancement in paddling activity, with a rise of approximately 90%. A notable response was observed under increased temperature, where the paddling rate surged by more than 2.6 times than expected, indicating a strong sensitivity to thermal changes. The most reduction in paddling activity occurred under low light intensity, with the rate plummeting to roughly 37% of the normal value. The findings underscore the susceptibility of N. glauca to variations in these key environmental parameters, particularly highlighting its heightened response to temperature fluctuations and low light conditions. The species of interest is observed as ecological sentinels and understanding its optimum limit of tolerance over fundamental physical parameters enables us to estimate the effect of climate change, environmental modifications and habitat alterations over the course of time.

Order Degree and Centrality Analysis of Advanced Fighter Environmental Control System and Thermal Management System

As fighter aircraft become more advanced, traditional air cycle systems have fallen short of meeting the complex environmental control requirements. Advanced fighters such as the F-22 Raptor have responded to these challenges by adopting integrated thermal management systems. These systems feature complex thermodynamic processes and intricate information transmission pathways among various components, creating a sophisticated network structure. To unravel the complexity of such systems, this paper employs a blend of thermodynamics and information theory. We conduct multi-level analysis using structure entropy method and centrality algorithms to explore the information transmission characteristics within these thermodynamic systems. At the system level, we find that variation in environmental parameters have only a 1% impact on order degree, whereas the influence from the system's own structure is more pronounced. At the component level, within the whole system, the varies components in AFT PAO and fuel loops emerge as critical hubs for information transmission. Among these components, the PAO/Fuel stands out as the most important, with closeness and betweenness centrality exceeding that of all other components by at least 11.5% and 29.1%. This study offers a theoretical foundation for the optimization of thermodynamic system structure and layout, viewed through the lens of information theory.

MUDA: dynamic geophysical and geochemical MUltiparametric DAtabase

Abstract. In this paper, the new dynamic geophysical and geochemical MUltiparametric DAtabase (MUDA) is presented. MUDA is a new infrastructure of the National Institute of Geophysics and Volcanology (INGV), published online in December 2023, with the aim of archiving and disseminating multiparametric data collected by multidisciplinary monitoring networks. MUDA is a MySQL relational database with a web interface developed in PHP, aimed at investigating possible correlations between seismic phenomena and variations in endogenous and environmental parameters in quasi real time. At present, MUDA collects data from different types of sensors such as hydrogeochemical probes for physical–chemical parameters in waters, meteorological stations, detectors of air radon concentration, diffusive flux of carbon dioxide (CO2) and seismometers belonging both to the National Seismic Network of INGV and to temporary networks installed in the framework of multidisciplinary research projects. MUDA publishes data daily, updated to the previous day, and offers the chance to view and download multiparametric time series selected for different time periods. The resultant dataset provides broad perspectives in the framework of future high-frequency and continuous multiparametric monitoring as a starting point to identify possible seismic precursors for short-term earthquake forecasting. MUDA can be accessed at https://doi.org/10.13127/muda (Massa et al., 2023).

Dynamics of phytoplankton community in relation to environmental variables in tropical mangrove estuary, Sundarbans, India

Aim: To explore the spatio-temporal variation of phytoplankton diversity and community structure, in response to associated environmental variables in Matla estuary, Sundarbans, India. Methodology: Monthly sampling was carried out from August 2022 to July 2023 at three locations within the estuary. Plankton was identified and its dynamics were studied in relation to the environment variables. Results: A total of 38 genera of phytoplankton, belonging to 8 classes, were identified. Spatial diversity was high in the upper reaches of the estuary, while temporal diversity peaked during the monsoon season. The majority of the abundance (96%) was contributed by four classes: Coscinodiscophyceae (35%), Mediophyceae (27%), Bacillariophyceae (25%) and Dinophyceae (9%). Bacillariophyceae exhibited higher species richness, while Coscinodiscophyceae dominated in terms of density. Cluster analysis and non-metric multidimensional scaling revealed four separate groups with varying spatio-temporal attributes. Analysis of variance (ANOVA) post-hoc tests highlighted significant variations in environmental parameters across seasons. Various phytoplankton groups were positively correlated with the physio-chemical parameters such as temperature, alkalinity, free CO2, NO3, NO2, silicate, temperature, orthophosphate and chlorophyll-a. Biota-environment stepwise analysis (BIO-ENV) underscored the importance of air temperature and free CO2 (ρ= 0.4929) as key factors shaping phytoplankton distribution and community structure. Canonical Correspondence Analysis (CCA) further showed the significant influence of parameters such as temperature, silicate, nitrite and orthophosphate on the phytoplankton community. Interpretation: Finding of this study enriches our comprehension of estuarine ecosystem dynamics, and this information may serve as a baseline study and thereby aid in framing management measures for long-term conservation and management of both biotic and abiotic components within estuaries. Key words: Environmental variables, Estuary, Mangrove, Phytoplankton, Sundarbans

Assessment of climatic and environmental parameters on fish abundance of an afro-tropical reservoir

This study assessed the impacts of climatic parameters (rainfall and temperature) and environmental variables (transparency, depth, chloride, TS, TSS, TOC) on the abundance of commercially important fish species in Esa-Odo. The research question was to find out if climatic and environmental factors influence the abundance of fish species in an afro-tropical reservoir. Fish species were collected on a monthly basis for two annual cycles covering both dry and rainy seasons. GIS-based climatic data was used to determine the relationship between climatic conditions and fish species abundance. Results showed that the highest abundance of fish was recorded during the rainy season, with Oreochromis niloticus being the most dominant species throughout the sampling period. Trend analysis revealed that variations in climate and environmental parameters influenced the abundance of different fish species in the reservoir. Mann-Kendal analysis indicated that an increase in rainfall led to an increase in reservoir depth, a decrease in transparency levels, and a reduction in temperature, with a Sen’s slope value of -38. Additionally, CCA and correlation matrix results demonstrated that climate and environmental parameters significantly influenced fish species abundance. The study emphasized the importance of climatic and environmental factors in the abundance of fish species in the reservoir, providing valuable information for future research on fishery resources. Governments and stakeholders were urged to prioritize the conservation and management of the reservoir’s fish population to prevent declines.

Density of Limnoperna fortunei larval stages in a cascade of subtropical reservoirs: spatiotemporal variation and environmental influences.

The golden mussel (Limnoperna fortunei) is an invasive bivalve that has established itself in several South American river systems, impacting ecosystem functioning. Reservoir cascades provide their larvae with the means of rapid dispersal, but the relationship between environmental variables and larval stage structure remains unclear. In this study, the density of three L. fortunei larval stages and quantitative detection using DNA are analyzed in a cascade of five reservoirs in the upper Uruguay River Basin and associated with spatiotemporal variation in environmental parameters. The analysis of L. fortunei eDNA presence and absence in freshwater systems appears to be a valuable mapping tool; however, no significant link was found between the eDNA magnitude and the overall larval density. The increase in larval density was related to the fluctuation of environmental parameters over a year, with the highest average larval densities observed in the CN and ITA reservoirs, though no significant difference was observed between the five reservoirs, where D-shaped larvae predominated. During winter, larval density decreased significantly, however, other variables also contribute to species activity and development in the upper Uruguay River Basin reservoirs and may be considered limiting factors. The relationships between environmental parameters were evaluated using a multivariate model. The interaction between reservoir area and precipitation, water temperature, electrical conductivity, and dissolved oxygen had a significant effect on larval density but showed specific influences on each larval stage. Any increase in density was regulated by dissolved oxygen and electrical conductivity content at all larval stages. Furthermore, total phosphorus affected the density of F1 and F3 larvae. The interaction between reservoir area and precipitation, nitrate content, phosphate concentrations, and water temperature had the most influence on the density of F2 and F3 larval stages; the F1 stage was mainly affected by calcium concentrations. The isolated effect of precipitation also contributed to the density of F2 and F3 larvae. Our findings shed light on the interaction between different phases of golden mussel larvae and the main nutrients found in reservoirs, which may be a determining factor in the rise in density of the non-native species in these systems.

Experimental and analytical study of a reverse-bootstrap air refrigerator for fresh air-conditioning

ABSTRACT The use of hydrofluorocarbons as refrigerants is reduced because of the increasing greenhouse effect. Air refrigeration system is environmentally friendly with air as working medium. In this study, a reverse-bootstrap air refrigeration cycle was proposed for fresh air-conditioning, which eliminated the hot heat exchanger to reduce volume and weight, and a full fresh air refrigerator was developed and tested in a psychrometric test room. Combining the characteristic curves of a motor-driven turboexpander–compressor (MTEC), a numerical model was established to analyze system off-design performance. The relative deviations between the predictions and experimental data were within 10%. The test and calculation were conducted at standard conditions (the outdoor and indoor dry and wet bulb temperature is 35/24°C and 27/19°C, respectively). The MTEC operating at design rotating speed 38 krpm could supply fresh air with a flow rate of 517.4 kg/h and temperature of 12.0°C, and a cooling capacity of 2.93 kW was obtained with a system Coefficient of performance (COP) of 0.315. The optimal COP and corresponding rotating speed will change with the variation of environmental parameters. As the outdoor temperature increases from 32 to 38°C, the optimal COP decreases by 29.6% and the corresponding rotating speed increases from 39.6 to 47.6 krpm. Moreover, when the outdoor relative humidity increases from 35% to 55% and the indoor temperature increases from 23 to 31°C, the COP decreases by 36.8% and increases by 31.9%, respectively. The advanced exergy analysis indicate the system avoidable exergy destructions account for 54.9%. Under the avoidable conditions, the efficiency of compressor, expander, and motor is 0.85, 0.85, and 0.95, respectively, the system COP can reach 0.946. The exergy destruction analysis of components indicates the importance to optimize the compressor.

Simulation-Informed Power Budget Estimate of a Fully-Implantable Brain-Computer Interface.

This study aims to estimate the maximum power consumption that guarantees a thermally safe operation for a titanium-enclosed chest wall unit (CWU) subcutaneously implanted in the pre-pectoral area. This unit is a central piece of an envisioned fully-implantable bi-directional brain-computer interface (BD-BCI). To this end, we created a thermal simulation model using the finite element method implemented in COMSOL. We also performed a sensitivity analysis to ensure that our predictions were robust against the natural variation of physiological and environmental parameters. Based on this analysis, we predict that the CWU can consume between 378 and 538mW of power without raising the surrounding tissue's temperature above the thermal safety threshold of 2 C. This power budget should be sufficient to power all of the CWU's basic functionalities, which include training the decoder, online decoding, wireless data transmission, and cortical stimulation. This power budget assessment provides an important specification for the design of a CWU-an integral part of a fully-implantable BD-BCI system.

Cabin air dynamics: Unraveling the patterns and drivers of volatile organic compound distribution in vehicles.

Volatile organic compounds (VOCs) are ubiquitous in vehicle cabin environments, which can significantly impact the health of drivers and passengers, whereas quick and intelligent prediction methods are lacking. In this study, we firstly analyzed the variations of environmental parameters, VOC levels and potential sources inside a new car during 7 summer workdays, indicating that formaldehyde had the highest concentration and about one third of the measurements exceeded the standard limit for in-cabin air quality. Feature importance analysis reveals that the most important factor affecting in-cabin VOC emission behaviors is the material surface temperature rather than the air temperature. By introducing the attention mechanism and ensemble strategy, we present an LSTM-A-E deep learning model to predict the concentrations of 12 observed typical VOCs, together with other five deep learning models for comparison. By comparing the prediction-observation discrepancies and five evaluation metrics, the LSTM-A-E model demonstrates better performance, which is more consistent with field measurements. Extension of the developed model for predicting the 10-day VOC concentrations in a realistic residence further illustrates its excellent environmental adaptation. This study probes the not-well-explored in-cabin VOC dynamics via observation and deep learning approaches, facilitating rapid prediction and exposure assessment of VOCs in the vehicle micro-environment.

Observation of mating behavior using marked flies of black soldier fly (Hermetia illucens) under sunlight condition

Abstract In recent years, various studies have investigated the growth of the larval stage of the black soldier fly (BSF). Nevertheless, the biology and reproductive behaviors of the adult is still largely unknown. Expanding the understanding of this area of research will assist the optimization of breeding-systems of BSF. In this present study, the mating behavior of BSF adults under summer sunlight conditions was evaluated. The number of couplings were evaluated based on a variety of environmental parameters that may have affected the copula: temperature (°C), humidity (RH) and light intensity (lux). 1000 g of pupae were put inside a cage to obtain one hundred adults to put in each three experimental units. Each specimen was then marked with an individual code in the dorsal portion of the thorax using fine-tipped acrylic markers and for each fly the body length parameters were taken. Individuals of interest were subsequently marked; in the first experiment only females, in the second only male, and in the third both sexes. During the trials observations were carried out from 9.30 am to 5.30 pm. During this time the key behaviors evaluated are as follows: mating, mating failure, struggles, deposition, failure to lay eggs, and multiple mating. The rate recorded in the Male and Female trials was 16.5%, but the peak of copulas changed with the trials. Mating events demonstrated strong positive correlation between light intensity (0.73) and humidity (0.64), whereas a negative correlation was seen between temperature and matings (−0.59). A weakly negative correlation was seen between deposition number and light intensity (−0.34) and humidity (−0.41), while positively correlated with the temperature (0.47). Multiple mating events were seen 2 times for females and up to 4 times for male.

Parenting in a changing environment: A long-term study of prolactin, parental effort and reproductive success in common eiders

Parental care is regulated by multiple endocrine mechanisms. Among these hormones, prolactin (PRL) is involved in the expression of parental behaviors. Despite the consensus that PRL mediates variation in parental effort with age and body condition, its role in the adjustment of parental effort to fluctuating environmental conditions, including changing predation pressure, still awaits further investigation. To shed light on this knowledge gap, we relied on a long-term monitoring of female common eiders Somateria mollissima (n = 1277 breeding attempts, 2012–2022) incubating under fluctuating predation risk to investigate the link between baseline PRL levels and female minimum age, body condition, clutch size, environmental parameters (predation pressure, climate, nest microhabitat) and hatching success. We predicted that PRL would be higher in older females, those in better condition or incubating larger clutches. We also predicted that females would reduce parental effort when nesting under challenging environmental conditions (high predation pressure or poor climatic conditions), translated into reduced baseline PRL levels. We also explored how variation in PRL levels, female characteristics and environmental parameters were related to hatching success. Following our predictions, PRL levels were positively associated with body condition and female age (before showing a senescent decline in the oldest breeders). However, we did not observe any population-level or individual-level reduction in PRL levels in response to increasing predation pressure. Population-level baseline PRL levels instead increased over the study period, coincident with rising predation threat, but also increasing female body condition and age. While we did not provide evidence for a direct association between baseline PRL levels and predation risk, our results support the idea that elevated baseline PRL levels promote hatching success under internal constraints (in young, inexperienced, breeders or those incubating a large clutch) or constraining environmental conditions (during years of high predation pressure or poor climatic and foraging conditions). Finally, the low repeatability of baseline PRL levels and high interannual variability highlight considerable within-individual flexibility in baseline PRL levels. Further research should explore flexibility in parental effort to changing environmental conditions, focusing on both baseline and stress-induced PRL levels.

The impact of oceanographic factors on the composition and abundance of mesopelagic fish communities in the central and equatorial Atlantic

This paper presents an overview of the composition and abundance of pelagic fish communities collected during the 43rd cruise of the R/V ′Akademik Sergey Vavilov' on the transect in the central Atlantic, from the Azores to the Equator, in autumn 2016. Samples were taken only at night with a Samyshev-Aseev modified Isaacs-Kidd non-closing midwater pelagic trawl (SAMT) at 18 stations from two depth of 0–200 and 0–700 m. The study recorded 112 species of juvenile and adult mesopelagic fishes belonging to 20 families at the sampled stations. The statistical analysis indicated notable disparities in the fish communities that were caught at depths of 0–200 and 0–700 m. Our study suggests that there are notable differences in pelagic fish associations between the North Atlantic anticyclonic gyre zone and the equatorial jets region, at both depths analyzed. These differences are most likely the result of variations in hydro-physical and other environmental parameters. It has been observed that deep-sea fish communities in the equatorial and central North Atlantic are capable of inhabiting at the same time multiple habitats that exhibit varying physical and chemical structures of water masses. This phenomenon highlights the remarkable ecological adaptability of the species that make up mesopelagic deep-sea communities, as well as their wide geographical distribution. The higher abundance and diversity of mesopelagic fishes observed at stations located above the Mid-Atlantic Ridge may be due to a general decrease in depth over the ridge compared to the surrounding regions and/or local circulations occurring over its crests. Thus, the tops and slopes of seamounts may become unique concentrations of mesopelagic fishes for a limited time due to their topography.

Proof of stability of an RSV Controlled Human Infection Model challenge agent

In 2018, SGS Belgium NV developed RSV-NICA (Respiratory Syncytial Virus-Nasobronchial Infective Challenge Agent), an RSV type A challenge agent for use in RSV Controlled Human Infection Model (CHIM) studies.It is widely recognized that the stability of RSV can be influenced by a variety of environmental parameters, such as temperature and pH. Consequently, our objective was to evaluate the stability of the viral titer of RSV-NICA following five years of controlled storage and to determine the uniformity of the viral titers across different vials of a GMP-qualified batch of RSV-NICA. In addition, we examined the capacity of RSV-NICA to infect human primary airway epithelial cells (MucilAir™), the principal target cells of RSV, and evaluated the influence of single and recurrent freeze–thaw cycles on the infectious viral titer of the challenge agent.The aliquoted RSV-NICA virus stock was subjected to standard virological and molecular methods to gather data on the titer and consistency of the viral titer contained within 24 representative vials of the stock. Our findings illustrate that over a span of five years of cryo-storage, the infectious viral titer in 75% of the tested vials exhibited a comparable average infectious viral titer (4.75 ± 0.06 vs 4.99 ± 0.11; p-value = 0.14). A considerable reduction down to an undetectable level of infectious virus was observed in the remaining vials. RSV-NICA demonstrated its capacity to effectively infect differentiated human airway epithelial cells, with active virus replication detected in these cells through increasing RSV genome copy number over time. Virus tropism for ciliated cells was suggested by the inhibition of cilia beating coupled with an increase in viral RNA titers. No discernable impact on membrane barrier function of the epithelial lung tissues nor cytotoxicity was detected. Pooling of vials with infectious titers > 4.0 log10 TCID50/ml and freeze-thawing of these combined vials showed no deterioration of the infectious titer. Furthermore, pooling and re-aliquoting of vials spanning the entire range of viral titers (including vials with undetectable infectious virus) along with subjecting the vials to three repeated freeze–thaw cycles did not result in a decrease of the infectious titers in the tested vials.Taken together, our findings indicate that long-term cryo-storage of vials containing RSV-NICA challenge agent may influence the infectious viral titer of the virus, leading to a decrease in the homogeneity of this titer throughout the challenge stock. However, our study also demonstrates that when heterogeneity of the infectious titer of an RSV stock is observed, rounds of pooling, re-aliquoting and subsequent re-titration serve as an effective method not only to restore the homogeneity of the infectious titer of an RSV-A stock, but also to optimize patient-safety, scientific and operational aspects of viral inoculation of study participants during at least the period of one RSV CHIM trial. RSV-NICA is a stable, suitable CHIM challenge agent that can be utilized in efficacy trials for RSV vaccines and antiviral entities.

Environmental control of interannual and seasonal variability in dinoflagellate cyst export flux over 18 years in the Cape Blanc upwelling region (Mauritania)

The increasing threat of anthropogenic environment and climate change amplifies the urgency to investigate the effect of these changes on marine ecosystems. We provide information about the export flux of organic-walled dinoflagellate cysts between 2003 and 2020 in the upwelling ecosystem off Cape Blanc (Mauritania), one of the world’s most productive regions. We compared the cyst export flux with variability in environmental parameters, such as wind speed, wind direction, dust emission, sea surface temperature (SST), SST difference between trap location and open ocean (SSTa), and chlorophyll-a concentration. This information is valuable to determine the ecological signal of dinoflagellate cysts that could be applied in recent and paleo records. The total export production of dinoflagellate cysts fluctuated between 0 - 1.18 x 105 cysts m-2 d-1 for the heterotrophs and 0 - 1.06 x 104 cysts m-2 d-1 for the photo-/mixotrophs. The export productions of both groups were in line with changes in upwelling intensity, which in most years, intensified in spring - summer. Dinoflagellate cyst association was dominated by heterotrophic taxa that formed an average of 94% of the association throughout the sediment trap record. A strong interannual variation in the cyst export fluxes, as well as the association composition was observed in the record. We identified five groups that showed comparable variability in export production with changes in environmental conditions: (1) maximal upwelling; Echinidinium delicatum/granulatum, E. transparantum/zonneveldiae, Echinidinium spp., Trinovantedinium spp., and Protoperidinium latidorsale, (2) combined maximal upwelling and dust input; Archaeperidinium spp., P. americanum, P. stellatum, and P. subinerme, (3) upwelling relaxation; Gymnodinium spp. and L. polyedra, (4) warm surface waters; Bitectatodinium spongium and Protoceratium reticulatum, (5) species with no specific relationship to the studied environmental variables; Brigantedinium spp., E. aculeatum, Impagidinium aculeatum, P. conicum, P. monospinum, Pentapharsodinium dalei, and Spiniferites spp. The sediment trap record documented a gradual shift in the cyst taxa association that co-occurred with the gradual increase of Saharan dust input to the region, notably after 2008. The cyst association contained five photo-/mixotrophic taxa that were formed by potentially toxic dinoflagellates. The latter could cause threats to the socio-economy of coastal communities.

Smart Hydroponic Systems: Optimizing Nutrient Levels with IoT Connectivity

Maintaining precise nutrient levels is essential for the thriving success of hydroponic systems. This comprehensive study delves into the intricate interplay of climatic conditions and nutrients, meticulously analysing various parameters like Total Dissolved Solids (TDS), pH, and electrical conductivity (EC) within a sophisticated smart hydroponic vertical Nutrient Film Technique (NFT) setup designed for leafy greens. The innovative system integrates a wireless sensor network and Internet of Things (IoT) connectivity, employing ESP32 microcontrollers as the primary unit alongside complementary hardware components for continuous and real-time monitoring of critical nutrient parameters. The investigation delves into the dynamic relationship between environmental factors and the growth patterns of spinach plants. Through a thorough examination of the extensive dataset gathered via deployed sensors, the study unveils variations in environmental parameters throughout various stages of plant development, including germination and root establishment. The study aims to elucidate the significance of each parameter in optimizing plant growth in hydroponic environments by analysing data associations. Results show higher Total Dissolved Solids (TDS) values correlate with better plant growth, while reduced pH levels harm plants. These findings are crucial for interpreting disease symptoms, aiding farmers in identifying issues early and optimizing yields. Understanding how nutrient values affect plant health enables proactive problem-solving. This research provides valuable insights into smart hydroponic systems, informing precision agriculture decisions.

Smart Hydroponic Systems: Optimizing Nutrient Levels with IoT Connectivity

Maintaining precise nutrient levels is essential for the thriving success of hydroponic systems. This comprehensive study delves into the intricate interplay of climatic conditions and nutrients, meticulously analysing various parameters like Total Dissolved Solids (TDS), pH, and electrical conductivity (EC) within a sophisticated smart hydroponic vertical Nutrient Film Technique (NFT) setup designed for leafy greens. The innovative system integrates a wireless sensor network and Internet of Things (IoT) connectivity, employing ESP32 microcontrollers as the primary unit alongside complementary hardware components for continuous and real-time monitoring of critical nutrient parameters. The investigation delves into the dynamic relationship between environmental factors and the growth patterns of spinach plants. Through a thorough examination of the extensive dataset gathered via deployed sensors, the study unveils variations in environmental parameters throughout various stages of plant development, including germination and root establishment. The study aims to elucidate the significance of each parameter in optimizing plant growth in hydroponic environments by analysing data associations. Results show higher Total Dissolved Solids (TDS) values correlate with better plant growth, while reduced pH levels harm plants. These findings are crucial for interpreting disease symptoms, aiding farmers in identifying issues early and optimizing yields. Understanding how nutrient values affect plant health enables proactive problem-solving. This research provides valuable insights into smart hydroponic systems, informing precision agriculture decisions.