Key Environmental Factors Research Articles

Impaired thyroid hormone sensitivity exacerbates the effect of PM2.5 and its components on dyslipidemia in schizophrenia

BackgroundDyslipidemia in schizophrenia causes a serious loss of healthy life expectancy, making it imperative to explore key environmental risk factors. We aimed to assess the effect of PM2.5 and its constituents on dyslipidemia in schizophrenia, identify the critical hazardous components, and investigate the role of impaired thyroid hormones (THs) sensitivity in this association. MethodsWe collected disease data on schizophrenia from the Anhui Mental Health Center from 2019 to 2022. Logistic regression was constructed to explore the effect of average annual exposure to PM2.5 and its components [black carbon (BC), organic matter (OM), sulfate (SO42−), ammonium (NH4+), and nitrate (NO3−)] on dyslipidemia, with subgroup analyses for age and gender. The degree of impaired THs sensitivity in participants was reflected by the Thyroid Feedback Quantile-based Index (TFQI), and its role in the association of PM2.5 components with dyslipidemia was explored. ResultsA total of 5125 patients with schizophrenia were included in this study. Exposure to PM2.5 and its components (BC, OM, SO42−, NH4+, and NO3−) were associated with dyslipidemia with the odds ratios and 95 % confidence interval of 1.13 (1.04, 1.23), 1.16 (1.07, 1.26), 1.15 (1.06, 1.25), 1.11 (1.03, 1.20), 1.09 (1.00, 1.18), 1.12 (1.04, 1.20), respectively. Mixed exposure modeling indicated that BC played a major role in the effects of the mixture. More significant associations were observed in males and groups <45 years. In addition, we found that the effect of PM2.5 and its components on dyslipidemia was exacerbated as impaired THs sensitivity in the patients. ConclusionsExposure to PM2.5 and its components is associated with an increased risk of dyslipidemia in schizophrenia, which may be exacerbated by impaired THs sensitivity. Our results suggest a new perspective for the management of ambient particulate pollution and the protection of thyroid function in schizophrenia.

Predicating risk habitats of Oncomelania hupensis, the intermediate host of schistosoma japonicum under multiple environmental drivers

BackgroundOncomelania hupensis (O. hupensis), the unique intermediate host for Schistosoma japonicum, exerts a substantial influence on the risk of schistosomiasis. Being amphibious freshwater snails, the growth, development, and reproductive distribution of O. hupensis are intricately tied to climatic environmental variables. This study aims to predict O. hupensis habitat risks along the Yangtze River in China, considering multiple environmental factors. MethodsData pertaining to the distribution of O. hupensis, including both presence and absence records, with the Jiangsu section of the Yangtze River basin for the period 2017–2021, were retrieved from the Jiangsu Schistosomiasis Control Information Platform. Ten machine learning algorithms and an ensemble model were used to explore environmental drivers. Three datasets (Snail_CLIM, Snail_TOPO, and Snail_ALL) incorporating climatic and topographic variables were examined for their impact on model accuracy. We conducted validation using the AUC and TSS metrics. Moreover, we utilized the data from the 2022 snail field survey for model external validation. ResultsThe findings demonstrate that snail_ALL, which incorporates both climatic and topographic variables, exhibits superior performance (ensemble model: sensitivity = 98.000, specificity = 95.960, AUC = 0.994). Among the ten model algorithms, Random Forest (RF) exhibited the highest degree of accuracy and stability (Snail_ALL: AUC = 1.000 ± 0.000, TSS = 0.985 ± 0.005). The key environmental factors affecting snail distribution included the distance to the nearest river, elevation, annual precipitation, and annual average pressure. High-risk areas manifested as two distinct concentrations: downstream of the Luhe District in Nanjing and at the confluence of Zhenjiang and Yangzhou. The results of 2022 field validation showed that over 90 % of the data points for snail breeding sites are concentrated in medium to high-risk areas. ConclusionBy selecting pertinent environmental variables and employing ensemble modeling techniques, we can accurately predict O. hupensis habitats. The resulting risk distribution map for snail habitats not only provides valuable insights but also serves as a guiding tool for targeted monitoring and control measures. The holds particular significance within the contest of the Yangtze River protection and restoration projects.

Dynamics and scale variations of blooms of Phaeocystis globosa “giant colony” ecotype and key environmental factors in the Beibu Gulf, China

The Beibu Gulf has experienced blooms of Phaeocystis globosa “giant colony” ecotype (PGGCE), with noticeable variations in bloom scale across years. However, driving environmental factors and their roles remain poorly understood. In this study, we quantified dynamics of PGGCE cells in 2016–2017 and 2018–2019, and analyzed their correlations with environment factors. The results revealed that PGGCE blooms primarily occurred in Guangxi coast and western waters of Leizhou Peninsula during winter months, exhibiting distinct developmental processes. Bloom intensity, duration, and distribution differed significantly between two bloom events. In 2016–2017, peak PGGCE density exceeded 2.0 × 105 cells L−1 nearly double that of 2018–2019. Furthermore, bloom sustained five months during 2016–2017, compared to three months during 2018–2019. Prolonged period of low temperatures and elevated nitrate concentrations favored PGGCE growth and colony formation, resulting in a larger scale bloom during winter 2016 as opposed to winter 2018.

Influence of oxygen partial pressure on homoacetogenesis and promotion of acetic acid accumulation through low pH regulation under microaerobic conditions.

Homoacetogenesis is an important pathway for bio-utilization of CO2; however, oxygen is a key environmental influencing factor. This study explored the impact of different initial oxygen partial pressures (OPPs) on homoacetogenesis, while implementing low pH regulation enhanced acetic acid (HAc) accumulation under microaerobic conditions. Results indicated that cumulative HAc production increased by 18.2% in 5% OPP group, whereas decreases of 31.3% and 56.0% were observed in 10% and 20% OPP groups, respectively, compared to the control group. However, hydrogenotrophic methanogens adapted to microaerobic environment and competed with homoacetogens for CO2, thus limiting homoacetogenesis. Controlling influent pH 5.0 per cycle increased cumulative HAc production by 18.3% and 18.2% in 5% and 10% OPP groups, respectively, compared with the control group. Consequently, regulating low pH effectively inhibited methanogenic activity under microaerobic conditions, thus increasing HAc production. This study was expected to expand the practical application of homoacetogenesis in bio-utilization of CO2.

Factors Affecting the Winter Distribution of Birds in Forests at the Eastern Edge of Europe

We show for the first time the results of a study into the spatial distribution of birds in forests at the eastern edge of Europe (Republic of Tatarstan, Russia) and changes from early to late winter. A transect method was used to census randomly selected plots spread over a large geographical area in the winters 2018/9–2022/3. We used regression and ordination methods to assess the influence of key environmental factors on species richness, total density of birds, biological diversity, and the probabilities of occurrence of individual species. The most abundant bird species in early winter was the Willow Tit, and in the late winter was the Common Redpoll. Compared with the end of the 20th century, the number of wintering bird species has increased in the study area, likely due to climate warming. Species richness, total density, and the Shannon Index of diversity were higher in early winter than in late winter. Species richness and the Shannon Index were also higher at low elevations and in the west of the study region. Our research shows strong ecological-geographical differences in the preferences of individual bird species in the studied forests. However, almost without exception, birds had a higher probability of occurrence at lower elevation and toward the west.

Organic carbon in Mollisols of the world − A review

Mollisols represent 29 % of agricultural land and they are considered to be one of the most fertile soils in the world. Here, we compare soil organic carbon (SOC) concentrations and pools of Mollisols for the globe, the USA and Poland, and review how differences are caused by climate, land use, and key environmental factors. Globally, the mean thickness of the A horizon in Mollisols is 50 cm. At 0–30 cm the mean SOC concentration is 2.3 %, SOC pool is 84 t ha−1, and clay content calculated at 0–50 cm soil depth is 21 %. Mollisols in the USA have an A horizon thickness of 36 cm and have a mean clay content of 27 % (0–50 cm). SOC concentrations are 2.0 and 1.7 % and SOC pools are 85 and 116 t ha−1 at 0–30 and 0–50 cm soil depth, respectively. Mollisols in Poland have SOC concentrations of 1.8 and 1.5 % at 0–30 and 0–50 cm soil depth, respectively, and lower clay content (17 %) at 0–50 cm depth. The SOC pool at 0–30 cm depth is 74 t ha−1 whereas it is 106 t ha−1 at 0–50 cm. At the global scale, the highest SOC concentrations and pools are in Mollisols from Eastern Europe (including Ukraine and Western Russia) and Asia, while the lowest SOC pools are found in Mollisols from South America. The Mollisols in Western and Central Europe and North America have similar SOC pools, although Mollisols in North America have higher SOC concentrations and lower A horizon thickness. Globally, the mean pH value of Mollisols is 7.1, and the pH is slightly lower in Mollisols of the USA (6.9 ± 0.9). The SOC concentrations and pools are strongly and positively correlated with clay content. Soil moisture and temperature regimes determine SOC concentration and pools in Mollisols, and higher SOC concentrations and pools are in Mollisols with frigid and frigid-cryic soil temperature regimes as well as aquic, xeric, and aridic soil moisture regimes. Mollisols under grassland have the largest SOC pools compared to those cultivated or under forest. The important environmental factors on SOC concentrations and pools in Mollisols worldwide are soil texture, land use, and soil temperature regime.

The effects of climate and soil depth on living and dead bacterial communities along a longitudinal gradient in Chile

Soil bacterial communities play a critical role in shaping soil stability and formation, exhibiting a dynamic interaction with local climate and soil depth. We employed an innovative DNA separation method to characterize microbial assemblages in low-biomass environments such as deserts and distinguish between intracellular DNA (iDNA) and extracellular DNA (eDNA) in soils. This approach, combined with analyses of physicochemical properties and co-occurrence networks, investigated soil bacterial communities across four sites representing diverse climatic gradients (i.e., arid, semi-arid, Mediterranean, and humid) along the Chilean Coastal Cordillera. The separation method yielded a distinctive unimodal pattern in the iDNA pool alpha diversity, increasing from arid to semi-arid climates and decreasing in humid environments, highlighting the rapid feedback of the iDNA community to increasing soil moisture. In the arid region, harsh surface conditions restrict bacterial growth, leading to peak iDNA abundance and diversity occurring in slightly deeper layers than the other sites. Our findings confirmed the association between specialist bacteria and ecosystem-functional traits. We observed transitions from Halomonas and Delftia, resistant to extreme arid environments, to Class AD3 and the genus Bradyrhizobium, associated with plants and organic matter in humid environments. The distance-based redundancy analysis (dbRDA) analysis revealed that soil pH and moisture were the key parameters that influenced bacterial community variation. The eDNA community correlated slightly better with the environment than the iDNA community. Soil depth was found to influence the iDNA community significantly but not the eDNA community, which might be related to depth-related metabolic activity. Our investigation into iDNA communities uncovered deterministic community assembly and distinct co-occurrence modules correlated with unique bacterial taxa, thereby showing connections with sites and key environmental factors. The study additionally revealed the effects of climatic gradients and soil depth on living and dead bacterial communities, emphasizing the need to distinguish between iDNA and eDNA pools.

Prediction of potential habitat areas of Rhododendron delavayi in China based on maximum entropy model MaxEnt

Rhododendron delavayi Franch. predominantly thrives in broad-leaved evergreen forests and bushes at altitudes of 1,200–3,200 meters. It favors a cool, moist climate and thrives in acidic soils. Due to its high ornamental, medicinal, and scientific values, understanding its ecological needs and optimal cultivation ranges is crucial. This study analyzing the key environmental factors and their thresholds affecting its distribution and predicts the future potential habitats of R. delavayi using existing distribution data alongside current and projected climate data. The results indicate that the primary environmental influencers are soil pH (4.9–5.4), precipitation in the driest month (10–20 mm), and altitude, contributing 41.8, 24.1, and 18.3%, respectively. It also shows a declining trend in suitable habitats: from 27.75 × 104 km2 under current conditions, to 3.69 × 104 km2 by the 2050s, and further to 2.65 × 104 km2 by the 2070s.

Effects of Waterlogging Stress on Root Growth and Soil Nutrient Loss of Winter Wheat at Seedling Stage

With global climate change, flooding events are becoming more frequent. However, the mechanism of how waterlogging stress affects crop roots needs to be studied in depth. Waterlogging stress can also lead to soil nitrogen and phosphorus loss, resulting in agricultural surface pollution. The aim of this study is to clarify the relationship between soil nitrogen and phosphorus distribution, root growth characteristics, and nitrogen and phosphorus loss in runoff water under waterlogging stress during the winter wheat seedling stage. In this paper, Zhengmai 136 was selected as the experimental material, and two water management methods (waterlogging treatment and non-waterlogging control treatment) were set up. Field experiments were conducted at the Wudaogou Hydrological Experimental Station in 2022 to assess the nitrogen and phosphorus concentrations in runoff water under waterlogging stress. The study also aimed to analyze the nitrogen and phosphorus content and the root distribution characteristics in different soil layers under waterlogging stress. The results showed as the following: 1. Waterlogging stress increased the characteristic parameters of winter wheat roots in both horizontal and vertical directions. Compared with the control treatment, the root length increased by 1.2–29.9% in the waterlogging treatment, while the root surface area and volume increased by an average of 3.1% and 41.9%, respectively. 2. Nitrogen and phosphorus contents in waterlogged soils were enriched in the 0–20 cm soil layer, but both tended to decrease in the 20–60 cm soil layer. Additionally, there was an inverse relationship between the distribution of soil nutrients and the distribution of wheat roots. 3. During the seedling stage of winter wheat, nitrogen loss was the main factor in the runoff water. In addition, nitrate nitrogen concentration averaged 55.2% of the total nitrogen concentration, while soluble phosphorus concentration averaged 79.1% of the total phosphorus concentration. 4. The results of redundancy analysis demonstrated that available phosphorus in the soil was the key environmental factor affecting the water quality of runoff water. Total phosphorus and dissolved phosphorus in the water were identified as the dominant factors influencing root growth.

Effects of the Three Gorges Dam on the mandarin fish larvae (Siniperca chuatsi) in the middle reach of the Yangtze River: Spatial gradients in abundance, feeding, growth, and survival

AbstractLarge dams significantly impact river ecosystems by disrupting connectivity, altering physicochemical variables, and modifying flow regimes. These modifications influence the spatial and temporal dynamics of biological processes and species distributions. While much research has focused on potamodromous species, there remains a gap in understanding the recovery gradients of resident species in dam‐altered rivers. This study examines the responses of larvae of a resident species, the mandarin fish (Siniperca chuatsi), to environmental alterations caused by the Three Gorges Dam (TGD) in the middle reach of the Yangtze River. We hypothesized that larval abundance, feeding, growth, and survival would exhibit longitudinal recovery gradients, improving with the increased distance from the TGD. Our results confirm this hypothesis, showing that larvae further from the TGD exhibited higher abundance, increased feeding intensity, enhanced growth rates, improved survival rate, and earlier peak abundance and hatching dates. Key environmental factors, including water temperature and discharge, increased downstream, while transparency decreased. Major tributary inputs significantly contributed to these recovery gradients. The observed longitudinal gradients in larval attributes mirrored environmental changes, underscoring the TGD impact on population recruitment. These results highlight the broader implications of dam‐induced changes on resident species recruitment, potentially affecting entire fish communities. Our study contributes to understanding the distinct spatial patterns of population trends, providing valuable insights for designing more effective conservation and management practices for resident freshwater fishes in large regulated rivers.

Environmental Influences on Illex argentinus Trawling Grounds in the Southwest Atlantic High Seas

To understand the spatial temporal distribution characteristics of Illex argentinus caught by trawl fishing vessels in the Southwestern Atlantic Ocean and their relationship with key marine environmental factors, this study analyzed the temporal and spatial changes in the fishing ground center of trawl vessels at the ten-day scale from December 2019 to May 2022, combining Chinese trawl fishing log data marine environmental data with satellite remote sensing marine environmental data. Utilizing the Maxent model, ten-day intervals were used as the temporal scale, and ten marine environmental factors, including sea surface temperature, sea surface height, sea surface salinity, chlorophyll concentration, temperature at 50 m and 100 m depth, and the meridional and zonal velocities of ocean currents were quantitatively analyzed to explore the correlation between the spatial distribution of catch and environmental factors. The study reveals that the trawl fishing grounds for Illex argentinus are divided into southern and northern grounds. The southern grounds first appear near 45°20′ S in December, gradually moving southeastward in February and March. The northern grounds do not appear until April, near 42° S in the high seas. On the ten-day time scale, the central fishing grounds of Illex argentinus show significant spatial variability but minor interannual differences. The Maxent model results indicate that sea surface temperature and chlorophyll a concentration are the key environmental factors influencing the spatial and temporal variability of the high seas trawl fishing grounds for most of the time, with high environmental contribution rates during the fishing season. While the range of suitable habitats with an HSI &gt; 0.6 identified by the Maxent model varies significantly between years, a pattern is observed where the range expands at the start and end of the fishing season and contracts during the peak fishing season. This suggests that a more concentrated range of suitable habitats is conducive to accurate predictions of trawl fishing grounds, enabling efficient fishing operations.

Functional brain connectivity predictors of prospective substance use initiation and their environmental correlates.

Early substance use initiation (SUI) places youth at substantially higher risk for later substance use disorders. Furthermore, adolescence is a critical period for the maturation of brain networks, the pace and magnitude of which are susceptible to environmental influences and may shape risk for SUI. We examined whether patterns of functional brain connectivity during rest (rsFC), measured longitudinally in pre-and-early adolescence, can predict future SUI. In an independent sub-sample, we also tested whether these patterns are associated with key environmental factors, specifically neighborhood pollution and socioeconomic dimensions. We utilized data from the Adolescent Brain Cognitive Development (ABCD) Study®. SUI was defined as first-time use of at least one full dose of alcohol, nicotine, cannabis, or other drugs. We created a control group (N = 228) of participants without SUI who were matched with the SUI group (N = 233) on age, sex, race/ethnicity, and parental income and education. Multivariate analysis showed that whole-brain rsFC prior to SUI during 9-10 and 11-12 years of age successfully differentiated the prospective SUI and control groups. This rsFC signature was expressed more at older ages in both groups, suggesting a pattern of accelerated maturation in the SUI group in the years prior to SUI. In an independent sub-sample (N = 2,854) and adjusted for family socioeconomic factors, expression of this rsFC pattern was associated with higher pollution, but not neighborhood disadvantage. Brain functional connectivity patterns in early adolescence that are linked to accelerated maturation and environmental exposures can predict future SUI in youth.

Community coalescence under variable hydrochemical conditions of the Chesapeake Bay shaped bacterial diversity and functional traits

Community coalescence related to bacterial mixing events regulates community characteristics and affects the health of estuary ecosystems. At present, bacterial coalescence and its driving factors are still unclear. The present study used a dataset from the Chesapeake Bay (2017) to address how bacterial community coalescence in response to variable hydrochemistry in estuarine ecosystems. We determined that variable hydrochemistry promoted the deterioration of water quality. Temperature, orthophosphate, dissolved oxygen, chlorophyll a, Secchi disk depth, and dissolved organic phosphorus were the key environmental factors driving community coalescence. Bacteria with high tolerance to environmental change were the primary taxa accumulated in community coalescence, and the significance of deterministic processes to communities was revealed. Community coalescence was significantly correlated with the pathways of metabolism and organismal systems, and promoted the co-occurrence of antibiotic resistance and virulence factor genes. Briefly, community coalescence under variable hydrochemical conditions shaped bacterial diversity and functional traits, to optimise strategies for energy acquisition and lay the foundation for alleviating environmental pressures. However, potential pathogenic bacteria in community coalescence may be harmful to human health and environmental safety. The present study provides a scientific reference for ecological management of estuaries.

Effects of straw management and N levels on gross nitrogen transformations in fluvo-aquic soil of the North China Plain

Straw incorporation with nitrogen (N) fertilization is crucial for enhancing soil fertility and minimizing negative environmental impacts by altering the magnitude and direction of soil N transformation processes. However, the response of soil N transformations to long-term carbon (C) and N inputs, and their primary driving factors, remain poorly understood. Thus, a 15N tracing study was conducted to investigate the effects of straw incorporation (AS) and straw removal (NS) with N levels of 0, 150 and 250 kg N ha−1 per season (N0, N150 and N250) on gross N transformation rates in the North China Plain after 6-year trial. Results indicated that at N0, AS significantly increased soil microbial immobilization of nitrate (NO3−-N, INO3) and autotrophic nitrification rates (ONH4) compared to NS. With N fertilization, AS increased gross N immobilization (Itotal), ammonium-N immobilization (NH4+-N, INH4), net NH4+-N immobilization (InetNH4) and net NH4+-N absorption rates (AnetNH4). Specifically, at N150, AS significantly increased recalcitrant organic N mineralization rate (MNrec), while significantly reducing ONH4, labile organic N mineralization (MNlab), and gross N mineralization rates (Mtotal). At N250, AnetNH4, MNlab, MNrec and ONH4 under AS were significantly higher than under NS. Nitrogen application significantly increased ONH4, Itotal and INO3 under two straw management practices, and enhanced INH4 and InetNH4 under AS. Compared to N250, N150 significantly increased INH4 and InetNH4 under AS, while decreasing Mtotal. Opposite results were observed under NS. Meanwhile, NO3−-N and dissolved organic carbon (DOC) were master factors controlling immobilization, total nitrogen (TN), hydrolysable NH4+-N (HNN) and stable organic N significantly affected AnetNH4, while labile organic N were the key environmental factors affecting MNrec, all of which positively influenced the rates of assimilation, mineralization and clay mineral adsorption. Overall, this study provides new insights into reducing N fertilization under straw incorporation by quantifying soil N transformation processes.

The pivotal role of phosphorus level gradient in regulating nitrogen cycle in wetland ecosystems

Phosphorus (P) is one of key drivers in Earth's nitrogen (N) cycle, however, the global overview of the P-regulated microbial community structure and gene abundance carrying wetland N process remains to be investigated. The key environmental factors that influenced wetland N cycle were initially screened, verifying the central role P. More complex and stable community interaction can be established in rich (20 mg/kg < P ≤ 100 mg/kg) and surplus P groups (P > 100 mg/kg) compared to that in deficient P group (P ≤ 20 mg/kg), with enhanced participation of betaproteobacteria and actinobacteria (i.e., changed hub microorganisms). Accordingly, P-mediated variations in gene expression patterns can be expected. On the one hand, the gene responses to carbon (C), N, and P factors presented nearly synchronous variation, highlighting the potential C-N-P coupling cycle in wetland ecosystem. On the other hand, the gene sensitivity towards environmental factors was changed at different P levels. Overall, the P level gradient can influence N cycle in direct (i.e., influences on gene abundances) and indirect (i.e., influences on gene response to environmental factors) manners. These findings provide important insights for controlling the N cycle in wetland ecosystems, particularly in cases where P levels are limiting factors.

Enhanced sinks of polystyrene nanoplastics (PSNPs) in marine sediment compared to freshwater sediment: Influencing factors and mechanisms

The difference in the transport behaviors of nanoplastics consistently assistant with their toxicities to benthic and other aquatic organisms is still unclear between freshwater and marine sediments. Here, the mobilities of polystyrene nanoplastics (PSNPs) and key environmental factors including salinity and humic acid (HA) were systematically studied. In the sand column experiments, both tested PSNPs in the freshwater system (100 nm NPs (100NPs): 90.15 %; 500 nm NPs (500NPs): 54.22 %) presented much higher penetration ratio than in the marine system (100NPs: 8.09 %; 500NPs: 19.04 %). The addition of marine sediment with a smaller median grain diameter caused a much more apparent decline in NPs mobility (100NPs: from 8.09 % to 1.85 %; 500NPs: from 19.04 % to 3.51 %) than that containing freshwater sediment (100NPs: from 90.15 % to 83.56 %; 500NPs: from 54.22 % to 41.63 %). Interestingly, adding HA obviously led to decreased and slightly increased mobilities for NPs in freshwater systems, but dramatically improved performance for NPs in marine systems. Electrostatic and steric repulsions, corresponding to alteration of zeta potential and hydrodynamic diameter of NPs and sands, as well as minerals owing to adsorption of dissolved organic matter (DOM) and aggregations from varied salinity, are responsible for the mobility difference.

Role of walkability, bike infrastructure, and greenspace in combatting chronic diseases: A heterogeneous ecological analysis in the United States

Associations of built and natural environment and bike infrastructure features with neighborhood-level hypertension and obesity prevalence across the U.S. are not well explored. Identifying the environmental determinants of neighborhood-level disease prevalence can support community-based nonpharmacologic interventions. Additionally, little is known about the extent of heterogeneity in built and natural environment impacts. Quantifying heterogeneity can help identify places where the greatest health gains can be obtained from infrastructural investments. Using a new neighborhood-level database, we assessed heterogeneous associations of neighborhood built and natural environment and bike infrastructure features with nationwide hypertension and obesity rates using a simultaneous quantile regression framework. A walkability index, access to green space, and bicycle infrastructure were negatively correlated with hypertension and obesity after controlling for social vulnerability. The associations of key environmental and bike infrastructure factors exhibited considerable heterogeneity. For a unit increase in the walkability index, the potential reduction in hypertension prevalence at the 10th percentile was 3.4 times the reduction at the 95th percentile. Likewise, the potential reduction in obesity prevalence at the 10th percentile was 1.8 times the reduction at the 95th percentile. Provision of on-street and off-street bike lanes was correlated with lower hypertension and obesity, although the impacts varied across the quantiles of health outcomes. Urban design policies promoting walkability, providing on-street and off-street bicycle facilities, and enhancing greenspace can be important strategies to combat hypertension and obesity. Our study underscores the importance of incorporating environmental features into future iterations of national disease prevalence data programs in the U.S.

Exploring Seasonal Variations in Fish Communities: A Study of the Yellow River Estuary and Its Adjacent Waters Using eDNA and Trawl Surveys

The Yellow River Estuary and its adjacent waters serve as crucial spawning, foraging, and nursery areas for marine organisms, possessing abundant biological resources. Monitoring fish communities provides a baseline for implementing the sustainable utilization of marine resources. In this study, data were collected from 15 spring surface and bottom sites and 17 summer surface sites using eDNA and trawl surveys. The results showed that 37, 40, and 35 fish species were detected using eDNA in the spring (surface and bottom) and summer (surface), respectively, with 38 fish species caught during summer trawling. The dominant species mainly belonged to Engraulidae of Clupeiformes in the spring and Gobiidae of Perciformes in the summer, characterized by smaller-sized, short-lived, and pelagic fish species. The summer surface communities exhibited higher diversity than the spring surface and bottom communities. NMDS analysis revealed a degree of seasonal differences in fish communities and that there may be a lack of vertical stratification in the spring communities. The pH and DO were identified as the key environmental factors affecting the fish community. Additionally, the combination of eDNA and trawl surveys was regarded as a superior survey method. Our study provides valuable information for understanding seasonal fish communities in the Yellow River Estuary and its adjacent waters, contributing to fishery resource management and conservation in the region.

Alkaline earth metal ions affect the dissolution of kaolinite-bearing olivine and its carbon storage effects

Olivine dissolution applications in coastal environments hold great promise for both ocean alkalinity enhancement and carbon dioxide storage. Yet the dissolution mechanism of olivine and the influence of metal ions, such as Mg2+ and Ca2+, remain unclear. Moreover, the weathering products, such as clay minerals are usually mixed with olivine, and the influence of the associated minerals on the dissolution also unexplored. In this study, an 80-day dissolution experiment was performed in Ca2+-free artificial seawater (ASW-Ca) and ASW lacking both Ca2+ and Mg2+ (ASW-CaMg), to elucidate the mechanism of olivine dissolution and the impact of Ca2+ and Mg2+ on the presence of an associated clay mineral, kaolinite. To evaluate the mineral properties before and after dissolution, X-ray diffraction spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy analyses were used. Etch pits were observed on olivine's surface as well as its reduced crystallinity. The atomic ratio of Mg/Si in olivine decreased from 1.49 ± 0.56 in the raw samples to 1.29 ± 0.53 in the samples obtained from ASW-CaMg after undergoing the 80-day dissolution, whereas it was much higher, at 1.85 ± 0.32, in the samples from ASW-Ca. The increasing Mg/Si was attributed to the Mg2+ adsorption on the surface of olivine, which inhibited the release of structural Mg2+. Hence, Mg2+ was a key environmental factor influencing the process of olivine dissolution, and estuaries, which have low Mg2+ content and low pH may be the promising areas for the olivine application. Moreover, in ASW-CaMg, the total alkalinity (TA), dissolved inorganic carbon (DIC) concentration, and charge concentration of alkaline earth metal ions increased by 3392 ± 28, 2922 ± 3, and 3740 ± 91 μmol kg−1, respectively, compared to the data from the blank experiment. Notably, TA and DIC had strong linear relationships with the alkaline earth metal ions (Mg2+ and Ca2+). The release of free alkaline earth metal cations during olivine dissolution was a controlling factor for long-term carbon dioxide storage in ASW-CaMg. Finally, during the 80-day dissolution experiment, no dissolution of the associated kaolinite was observed, however, kaolinite may influence the olivine dissolution by adsorbing the released Si.

Effect of Soil Acidification on Temperature Sensitivity of Soil Respiration

Soil pH significantly impacts microbial activity and community assembly, which in turn determines the temperature sensitivity (Q10) of soil respiration. Due to the high soil acidification in China, it is necessary to understand how soil acidification impacts Q10. Here, the Q10 of soil respiration was examined in a long-term field experiment (1982–present) with different soil pH caused by fertilization management. In this experiment, we selected treatments with neutral pH: (1) no crops and fertilization (CK); (2) crops without fertilization (NF); low pH with (3) crops with chemical fertilization (NPK); and (4) crops with chemical fertilization combined with wheat straw incorporation (WS). Under natural soil temperature changes, we observed that soil acidification lowered the Q10 value of soil respiration. Considering only temperature changes, the Q10 of soil respiration was strongly associated with microbial community composition, alpha diversity, and soil ammonium nitrogen. Considering the interaction between soil pH and temperature, warming strengthened the negative effect of soil pH on the Q10 of soil respiration, and the pathway through which soil pH mediated Q10 included not only microbial community composition, alpha diversity, and biomass but also the soil’s available phosphorus. This work enhanced our insights into the relationships between Q10, temperature, and soil pH by identifying important microbial properties and key soil environmental factors.