Percent Cover Research Articles

Elephant pathway use in a human‐dominated landscape

Habitat loss and fragmentation are two of the biggest threats facing wildlife today. Understanding the role of wildlife pathways in connecting resource areas is key for maintaining landscape connectivity, reducing the impacts of habitat loss and helping address human–wildlife conflict. In this study, we used sign surveys and camera trapping to understand the fine scale movement of elephants moving between a protected area and agricultural zone in the Masai Mara, Kenya. We used generalised linear models to determine factors driving high frequency of pathway use by elephants. Our results showed strong seasonal trends in pathway use, with peaks coinciding with the dry season. However, no correlations between rainfall and pathway use were found. Temporal patterns of pathway use indicate that elephants use risk avoidance strategies by moving between the two areas at times of low human disturbance. Spatial analysis revealed that the most frequently used pathways were closer to farms, saltlicks and forest and those that had a higher percentage of forest cover. Our models also showed a positive relationship between pathway use and the number of elephant crop raiding incidents, highlighting that pathways can play a role in human–elephant conflict. As habitat loss continues, pathways may become more important for linking resources. However, they are also likely to facilitate movement into farmland. The results from this study provide an opportunity for planned management activities to ensure connectivity and to mitigated conflict.

Risk of invasive waterfowl interaction with poultry production: Understanding potential for avian pathogen transmission via species distribution models.

Recent outbreaks of highly pathogenic avian influenza have devastated poultry production across the United States, with more than 77 million birds culled in 2022-2024 alone. Wild waterfowl, including various invasive species, host numerous pathogens, including highly pathogenic avian influenza virus (HPAIV), and have been implicated as catalysts of disease outbreaks among native fauna and domestic birds. In major poultry-producing states like Arkansas, USA, where the poultry sector is responsible for significant economic activity (>$4 billion USD in 2022), understanding the risk of invasive waterfowl interactions with domestic poultry is critical. Here, we assessed the risk of invasive waterfowl-poultry interaction in Arkansas by comparing the density of poultry production sites (chicken houses) to areas of high habitat suitability for two invasive waterfowl species, (Egyptian Goose [Alopochen aegyptiaca] and Mute Swan [Cygnus olor]), known to host significant pathogens, including avian influenza viruses. The percentage of urban land cover was the most important habitat characteristic for both invasive waterfowl species. At the 95% confidence interval, chicken house densities in areas highly suitable for both species (Egyptian Goose = 0.91 ± 0.11 chicken houses/km2; Mute Swan = 0.61 ± 0.03 chicken houses/km2) were three to five times higher than chicken house densities across the state (0.17 ± 0.01 chicken houses/km2). We show that northwestern and western Arkansas, both areas of high importance for poultry production, are also at high risk of invasive waterfowl presence. Our results suggest that targeted monitoring efforts for waterfowl-poultry contact in these areas could help mitigate the risk of avian pathogen exposure in Arkansas and similar regions with high poultry production.

Stream size‐dependent effect of urban land use on occupancy of an apex freshwater carnivore recolonizing past ranges

AbstractAccurate assessment of population trends and factors that limit distributions of threatened species is key to conserving biodiversity. A reduction in impacts of human land use on species habitats may be one of the factors involved in the recolonization of former ranges by native species. The signature of this process could be detected as a temporal reduction of land use effects on species distributions, or as a spatial reduction, with effects persisting only in habitats more sensitive to anthropogenic stressors. We explored these hypotheses in a recolonizing semiaquatic carnivore. Our species of interest was the Eurasian river otter (Lutra lutra) in Italy, a nationally vulnerable species with a restricted but expanding range. Human land use is likely to strongly affect riparian and stream communities through habitat degradation. We used three independent survey datasets collected in 2003, 2009, and 2019 at the southern range periphery, and unpaired‐site occupancy models to account for imperfect detection in otter surveys. To assess how land use affects recolonization by otters, we tested three main model predictions: (1) occupancy increased over years, (2) effects of agricultural and urban land cover on occupancy decreased over years, (3) effects of agricultural and urban land cover were constant across years and changed with stream size and elevation. We found evidence that otter occupancy increased over years, with predicted mean occupancy of 0.27 in 2003 and 0.65 in 2019. An interaction effect of urban land cover with stream size was the strongest predictor of otter occupancy. Interestingly, a higher percentage of urban land cover around streams was predicted to reduce the probability of occupancy at smaller streams, but did not influence occupancy at larger streams. Despite a large increase in occupancy, otters at the southern periphery of the Italian range are still unable to colonize small rivers in urbanized areas. This pattern supports our hypothesis that human land use can affect recolonizing species at sensitive habitats, considering the intrinsic vulnerability of small stream ecosystems to anthropogenic stressors. Restoring small streams impacted by urban areas can be a valuable conservation action to increase habitat connectivity and favor recolonization of otters.

Little prairie under the panel: testing native pollinator habitat seed mix establishment at three utility-scale solar sites in Minnesota

As more land is being utilized for large-scale solar energy projects, there are increasing discussions from stakeholders on how to utilize land under solar panels to promote biodiversity. One path is to plant habitat beneficial to pollinators and other insects, but there have been few long-term studies that examine how different vegetation and seed mixes establish underneath solar panels. This study addresses a scientific gap to determine whether native pollinator seed mixes successfully establish over time under solar arrays using a systematic assessment of eight seed mixes planted at three utility-scale solar sites in Minnesota. We assess establishment with a percent native coverage metric, which is an assessment of native species observations compared to total observations during percent cover analyses in our vegetative test plots. The percent native coverage metric allows for a measurement of how the seed mix established and how the seed mix persists over time. The percent native coverage under and in between the solar photovoltaic (PV) arrays rose from 10% after one year of planting to 58% after three years across all sites, while the native coverage of the full sun control area rose from 9.6% to 70% under the same period, showing that native prairie and pollinator plants successfully established under the array, although to a lesser extent than in full sun conditions. Percent native coverage under the PV arrays rose 5- to 8-fold for each of the three sites from over the course of the study, while the coverage of weeds decreased for all three sites over the same period. Percent native coverage varied by seed mix over the project years, but every seed mix experienced a higher percent native coverage year after year under the PV arrays. Our results did not indicate a difference in establishment across placement within the array; the center, west, and east portions of the areas in between panels had similar establishment rates at two out of three sites, indicating that the same seed mix can be applied throughout the array. Out of 101 plant species seeded, we observed the establishment of 68 species in our vegetative test plots, and we detailed the top 20 observed species to inform future seed mix development. Based on these findings, native pollinator vegetation can establish over time at solar arrays, and it can be suitable for creating habitat at utility-scale solar sites.

A Single-Step Root Coverage Procedure Using Modified Bridge Flap Technique and De-epithelialized Gingival Unit Graft: A Prospective Clinical Study.

The mucogingival conditions associated with the recession defects at the mandibular anterior region, not only make plaque control difficult to be performed by the patient but also pose a problem in passively advancing the tissues at the recipient site. This surgical technique is used to treat multiple recession defects in the mandibular anterior region. Twenty-five sites in 17 subjects (11 women and 6 men) underwent modified bridge flap and de-epithelized gingival unit graft (d-GUG) as a single-step treatment modality to cover the denuded root surface, as well as increase the width of keratinized gingiva in recession type 1 gingival recession defects in the mandibular anterior region. Nearly 60% of sites in our study showed complete root coverage, with a mean root coverage percentage of 88.08%. Furthermore, keratinized tissue width, keratinized tissue thickness as well as vestibular depth showed statistically significant increases as compared to baseline levels. Thus, the modified bridge flap technique using d-GUG within the limitations of our study design, showed promising results in terms of recession coverage as well as management of the difficult mucogingival conditions at the mandibular anterior region.

Growth factor-enhanced matrix combined either with free connective tissue graft or with collagen membrane in the treatment of Miller class II gingival recession

Abstract Purpose The goal of the study was to examine the efficacy of collagen membrane or free connective tissue graft in conjunction with growth factor-enhanced matrix (GEM) for treating Miller class two gingival recession. Patients and methods Twenty sites in 10 patients, with class II Miller gingival recession were allocated randomly to be treated by (GEM21s) with free connective tissue graft (group I) or GEM21s with collagen membrane (group II). Recession width, recession depth, height of keratinized tissue and digital measurements were recorded at baseline, 1, 3, and 6 months. Probing pocket depth, clinical attachment level, gingival thickness, and radiographic parameters were recorded at baseline and 6 months. Root coverage percentage were recorded 6 months postoperative and wound healing index were recorded at 1, 3, and 6 months postoperative. Results Both groups showed significant improvement in all clinical parameters and increase in bone level was observed after 6 months compared to baseline measures. There was no statistically significant difference between both groups except for recession depth at 1 and 3 months after surgery and height of keratinized tissue at 1, 3, and 6 months in favor of group I. Radiographically there was a statistically significant difference (P ≤ 0.05) in amount of labial bone gain and bone density in favor of group I compared to group II. Conclusion GEM21s combined either with free connective tissue graft or collagen membrane led to favorable gingival coverage and radiographical results with better results for free connective tissue graft with GEM21s.

Effects of management practices on Northern Bobwhite Colinus virginianus density in privately owned working forests across the Southeastern United States

Abstract Obtaining rigorous baseline density estimates of species of conservation interest is key when assisting landowners to achieve management goals on private lands. Northern bobwhite (Colinus virginianus) populations are declining throughout their range and despite being the focus of numerous private land conservation initiatives, baseline density estimates in privately owned pine forests are lacking. We sought to address this knowledge gap across the Southeastern United States by sampling 105 privately owned pine stands throughout 2018 to 2020 using observer point count and autonomous recording unit (ARU) sampling data. Using Bayesian hierarchical models, we investigated the influence of stand management (brush management or applied fire) on bobwhite density, as well as four landscape‐scale environmental variables. These included percentage cover of forest, herbaceous, agricultural or burnt land area across six different spatial scales ranging from 500‐m to 10‐km around each pine stand. Baseline density on sites with no management was estimated to be 2.24 coveys per 100 ha (1.00–5.03, 95% BCI), with little impact of applying brush management, but a trend for a positive effect of fire management (0.19, −0.01 to 0.38 95% BCI). This impact of fire was seen at both the stand‐scale, correlated with an increase in acreage of applied prescribed burn management, and across the greater landscape area, correlated with cover of burnt area within a 2‐km buffer around each site. There were also strong positive influences of herbaceous vegetation and a strong negative influence of forest cover on bobwhite density. Practical implication: our sampling efforts fill an important information gap regarding densities throughout private lands in the Southeastern United States. Our study also highlights the necessity of landscape scale planning for Northern Bobwhite conservation initiatives because the efficacy of conservation practices (i.e. prescribed fire and brush management) could be altered by the landscape surrounding the treated forest stand.

The Driving Forces that Influence Land Use Land Cover Changes in Khwisero Sub County, Kakamega County, Kenya

Land use land cover changes have to a great extent changed the world's landscapes, rebuilding environments and what they provide to humans during the time spent supporting the rising population across the globe. The drivers of these changes vary from location to location causing varying effects that challenge the essential design and the functioning capacity of the land quality with flowing consequences to land quality. A cross sectional descriptive design together with a longitudinal design were used. A random sampling was used to obtain a sample size of 384 from a study population of 113,476. Based on agriculture, forest land, bare land and built up land categories, the study classified Landsat images through supervised classification algorithm then applied post - classification comparison change detection to measure land use land cover percentage area change over time. Primary data was collected through interviews and discussions with key informants, field observations, and questionnaires administered to individual households in Khwisero Sub County. Secondary data involved downloading Landsat images (Landsat 7, 8 and 9; 30-meter multispectral), summaries and citation of other works carried in journals articles, original documents, annual reports, development plans and internet. Quantitative data analysis involved measures of central tendency and measures of dispersion (SPSS) and analysis of variance (ANOVA). Qualitative data was analysed by organizing and grouping the arising issues into various categories relevant to the study. Land use land cover classification of the study area realized four land use land cover classes of agriculture 81.34 km2, forest 52.75 km2, built up 8.86 km2 and bare land 2.65 km2 for the study area as at 2023. Change detection noted that agricultural land use has been reducing from 2002 to 2023, built up has been increasing from 2002 to 2023, bare land increased between 2002 to 2012 but decreased between 2012 and 2023 while forests reduced between 2002 to 2012 but increased between 2012 to 2023 Accuracy assessment for the land use land cover classes for 2002 was 85.45% with a Kappa coefficient of 0.756, 2012 was 83.64% with a Kappa coefficient of 0.5454 while 2023 was 81.82% with a Kappa coefficient of 0.6034 for the land use land cover classes revealing that the classification is accurate. The study revealed that LULCCs are driven by settlement, poverty and climate change mostly thus affecting cropland vegetation and soil fertility majorly. The study concluded that LULCC drivers varied from location to location even within the sub county. The study recommends creation of awareness of understanding the various drivers of LULCCs and impact of each on land quality.

Benthic community structure and geomorphology of uncharted nearshore reefs in Kuantan coastal waters.

The nearshore reefs play several important ecosystem functions in marine environments, especially in coastal areas. Six relatively unknown nearshore reef sites were surveyed in the southern Kuantan coastal waters using the coral video transect (CVT) technique between April 2021 and September 2022 to estimate coral reef benthic components. Data analysis on coral reef benthic components indicated that these uncharted nearshore reefs have ‘fair’ coral cover with an average percentage of 39.4 % ± 17.8 in which ST 1 recorded the highest live coral cover coverage with 68.06 %. Abiotic components (sand and rock) were the second-most abundant and the coverage of dead coral was relatively low at all stations. A total of 33 coral genera were recorded in this study in which Porites, Acropora and Montipora mean percentage cover dominated most of the reef sites. Bathymetry data indicated that some of these uncharted reefs were located on submerged shoals with a depth range between 12 – 17 meters. The variation in benthic community composition observed among reef sites highlights the importance of location-specific management and conservation strategies.

Mapping benthic sediment types and composition in a turbid Jamaican bay using hydroacoustic data and different spatially explicit interpolation techniques

Hydroacoustic sensors are better suited for mapping shallow turbid coastal waters, but surveys must take place along transects, necessitating the interpolation of processed, large, spatially dependent hydroacoustic datasets to produce continuous maps. The aim of this study was to evaluate the performance of interpolation techniques that can handle data obtained from a hydroacoustic survey (covering 23 km2) conducted in 2016 in a shallow bay in southwestern Jamaica. Independent data or a 5-fold cross validation were used to compare the accuracies of continuous maps of benthic sediment percentage composition and submerged aquatic vegetation cover (SAV), interpolated from the survey data using random forest (RF) regression (RFr), RFr kriging (RFrk) and Ensemble Machine Learning (EML) with rotated/oblique coordinates. Categorical/thematic maps of sediment types interpolated using RF (RFc) and EML classifiers and a spatial Markov chain model with indicator kriging predictor/simulation (Mc-IK) were also compared. RFr, RFc, RFrk and EML covariates included coordinates and auxiliary data. The following maps were more accurate than corresponding interpolated maps: EML - mud, sand, silt, clay and SAV; RFr - loss on ignition [LOI]; RFrk - calcium carbonate; Mc-IK – sediment types with 3 and 4 classes. The Mc-IK maps were also the most suitable maps for assessing spatial and quantitative changes. The predominant substrate type in the bay was muddy sand covering 15.7 km2. The highest percentage composition of mud, silt, clay, and organic matter [LOI] was found close to the mouth of the Black River where sandy mud was found, indicating a high input of terrigenous sediment. Calcium carbonate composition showed an opposite spatial trend and was positively associated with higher SAV percentage cover. The bay is now part of a protected area, as such, these maps will be used as a baseline to gauge the impact of increased protection/management on benthic dynamics.

Conserving ecosystem integrity: Ecological theory as a guide for marine protected area monitoring.

Global policies increasingly focus on the importance of maintaining or improving the integrity of ecosystems, but defining, assessing, and monitoring integrity in marine protected areas (MPAs) remains a challenge. In this paper, we conceptualized ecological integrity along dimensions of heterogeneity and stability containing seven components: physical structure, diversity, function, persistence, resistance, resilience, and natural variability. Through a structured literature search, we identified indicators and metrics used for quantifying ecosystem status components in the marine environment, then reviewed MPA management plans worldwide for inclusion of these components. We evaluated 202 papers applying 83 ecological indicators built from 72 metrics. Ecosystem components were most comprehensively addressed by metrics of taxa presence, organisms count, and area occupied by benthic organisms, and community structure, biomass, and percent cover indicators. Of the 557 MPA management plans we reviewed globally, 93% used at least one ecosystem status term or its synonym in an ecologically relevant context, but 39% did not address any components of stability. In particular, resistance was mentioned in only 1% of management plans, but in some cases it may be inferred from indicators and metrics used to track the best addressed component in management plans, diversity. Plans for MPAs with both an ecological/biological purpose and a research and education purpose contained ecosystem status terms more frequently than other plans, suggesting that engagement with the scientific community may have improved the application of these terms. An improved understanding of how to operationalize and measure ecological integrity can help MPA monitoring and management.

Effects of heading date and Epichloë endophyte on persistence of diploid perennial ryegrass (Lolium perenne). 2. Endophyte strain and interactions with heading date

Context Data are lacking on the effects of selected endophytes of perennial ryegrass (Lolium perenne L.) on ryegrass persistence. Aim We aimed to determine the impact of Epichloë endophyte on the persistence of mid- and late-heading perennial ryegrass cultivars. Method Two mid-heading (Samson, Bronsyn) and two late-heading (One50, Rohan) cultivars, infected with selected endophytes (AR37, nea2/6) or with standard toxic endophyte, were established in a replicated plot study grazed by cattle in a subtropical environment of the upper North Island of New Zealand. Persistence characteristics were quantified at least five times per annum, over 4 years. Key results Endophyte strain had an effect on persistence; infection with standard endophyte resulted in higher ryegrass ground cover percentage, ryegrass content in pasture dry matter and autumn yield than infection with nea2/6 on many occasions, and with AR37 on some occasions. There were negligible impacts on ryegrass tiller density or nutritive value. Trends were dominated by the main effect of endophyte; interactions with heading date were inconsistent. Conclusions Cultivars were more persistent when infected with standard endophyte than with selected endophytes, although persistence declined over 4 years for all cultivars and irrespective of heading date. Implications Reliance on selected endophyte is unlikely to prevent persistence decline of perennial ryegrass in a subtropical environment. Other strategies will be required to maintain the persistence of high-quality pastures based on perennial ryegrass.

Mapping Student-Generated Learning Objectives Against USMLE Core Content

Purpose: To compare the content covered by student-generated, case-based, learning objectives with United States Medical Licensing Exams (USMLE) core-content guidelines, both in terms of range of topics covered and time spent with different topics. Secondarily, to examine the impact of online learning during the COVID-19 pandemic on the content covered by student generated learning objectives (SGLOs). Methods: The data used in this study was drawn from university records of SGLOs over the course of five years, including approximately 1,600 individual SGLOs, organized by semester and year. SGLOs were coded to correspond to topics on the USMLE core content guidelines. Two lists of core content provided by the USMLE were used in this study. The first consisted of 18 broad topics and 222 nesting subtopics tested on STEP 1. The second consisted of 11 broad topics with a corresponding percent range of how many questions on STEP 1 address that topic. Findings: Percent Coverage: 50-60% of USMLE core content topics are covered within the first year. Multiple regression analysis showed this number remaining consistent between first year classes, between semesters, and during COVID. Topic Weight: 7 out of 11 broad topics fell within the same ranges of the USMLE, with Social Sciences being the greatest outlier (significantly more coverage). 2 out of 11 topics were addressed less by SGLOs than by the USMLE. Gaps: 53 individual USMLE core content sub-topics were not addressed by a UP first year class in any learning objective. Notable trends in the identified content gaps included topics relating to congenital disorders, embryonic development, male and female reproductive systems, endocrine disorders (other than thyroid disorders and diabetes), normal ageing and age-related changes, psychiatric disorders and behavioral health, and drug adverse effects. Conclusions: SGLOs covered consistent amounts of material from year to year, suggesting curricular stability over time. The same standard of SGLO creation was also maintained during online COVID 19 activities. The agreement in weighting of topics between our student-driven curriculum and the USMLE core content indicate that students prioritize topics effectively. Identified gaps in coverage represent areas for improvement. This study further supports successful collaborations between faculty and medical students in regards to curriculum development and execution. Conflicts of Interest: None. This study (Study ID: STUDY00015600) was deemed exempt by the Institutional Review Board (IRB) at the Penn State College of Medicine.

Directional succession and species-specific patterns observed in repeat study of vascular plants at three glacier foreland chronosequences in the Canadian High Arctic

This paper presents the first repeat study of glacier foreland chronosequences conducted in the Canadian High Arctic. Vascular plant species at three forelands on Ellesmere Island, Nunavut first surveyed in 1995 were resurveyed 21 years later to (1) test the original hypothesis that succession on these forelands was directional, and (2) investigate the use of the chronosequence method in High Arctic succession studies. Forelands were surveyed using percent cover estimates or presence/absence counts. Indicator species analysis and rates of change were used to quantify shifts. Total plant cover and species richness increased on younger terrain. Rates of peak cover and first appearance advance varied greatly between species and forelands, but were generally faster for graminoid and forb species than shrub species. We observed a pattern of directional succession at all three forelands, supporting the original hypothesis. However, species-specific patterns and rates of change acted to create assemblages that differed between 1995 and 2016, different successional trajectories were observed between the three forelands, and the first occurrence of most species was further from the glacier margin in 2016 compared to 1995. These results demonstrate the importance of repeat studies over time and replication over space to confirm observations in chronosequence studies.

Impact of biocrust on soil nitrogen maintenance and microbial composition in citrus orchards under varying urea application rates

Biocrust communities and their effects on soil nitrogen (N) content in natural drylands have been extensively studied. However, their significance in citrus orchards, which are typically managed with N fertilizer, remains unclear. To address this, an investigation was conducted in a citrus orchard subjected to varying levels of urea application (0 %, 70 %, and 100 % of the local N fertilizer application) over three years. The study focused on biocrust communities dominated by bryophytes, examining their community and individual characteristics, and comparing the properties and microbial communities of soils with and without biocrust cover. The results showed that biocrust had the highest percent coverage (56.1 %) in the plot with 70 % local N fertilizer application. Dicranella heteromalla was the dominant biocrust species across all treatments, exhibiting greener and longer leaves with 70 % local N fertilizer application. Biocrust cover significantly (P < 0.01) influenced soil total nitrogen content, soil water content, soil total carbon content, and soil dissolved organic carbon content. In contrast, fertilizer application had non-significant effects on the physicochemical properties of soils, regardless of biocrust cover. A notable difference in bacterial phyla composition was observed between soils with and without biocrust cover (PERMANOVA, P = 0.001), although fertilization did not significantly affect the bacterial diversity index. Additionally, biocrust cover significantly (P < 0.01) influenced predicted soil bacterial functional groups, including ureolysis and nitrogen fixation, while fertilizer application had a weaker impact on these bacterial functional groups. In conclusion, nitrogen application altered the community and dominant species characteristics of biocrust but did not overshadow the effects of biocrust on soil N dynamics. In the citrus orchard with varying levels of urea application, biocrust played a crucial role in soil water retention, N maintenance, and predicted microbial ecological functions related to N cycling.

Marine biocorrosion inhibition of Pseudomonas sp. biofilms on 304 stainless steel coated with poly-6-aminoindole produced by two different electrochemical methods

Forming a bacterial biofilm on a metallic surface could result in biocorrosion and biofouling development. New environmentally friendly coatings are required to protect infrastructure, especially in coastal and marine environments. This study aimed to evaluate the mitigation of biocorrosion produced by Pseudomonas sp. biofilms on AISI 304 stainless steel (SS304) coupons modified with poly-6-aminoindole (PAIn) using two electrochemical techniques: cyclic voltammetry (SS/6-PAIn CV) and chronoamperometry (SS/6-PAIn CA). Experimental trials were performed in two stages: (i) the settlement and colonization of bacteria (1 h of incubation) and (ii) biofilm development (7 days of incubation). Colonized surfaces were characterized by epifluorescence and field emission scanning electron microscopy. Biocorrosion mitigation was evaluated using linear resistance polarization, electrochemical impedance spectroscopy, and linear scanning voltammetry in simulated seawater at 20 °C. The results showed biofilm formation on SS304 and SS/6-PAIn CA, but in SS/6-PAIn CV, the coating considerably reduced biofilm formation, with alterations in the size and structural organization of the biofilm. The biofilm cover percentages were 31.63 %, 22.66 %, and 9.25 % for SS304, SS/6-PAIn CA, and SS/6-PAIn CV, respectively. Thus, SS/6-PAIn CV reduced biofilm growth by 70.76 % compared to bare SS after seven days of culture. Electrochemical parameters determined by LSV and EIS showed a significant improvement in charge transfer resistance and coating resistance for the SS/6-PAIn CV compared to the coating produced by chronoamperometry. Although both coatings protected the metallic surface, SS/6-PAIn CV presented the best protective properties, emerging as a promising alternative coating to mitigate the biocorrosion process of SS304 in a marine environment.

Association of greenspace and natural environment with brain volumes mediated by lifestyle and biomarkers among urban residents

ObjectivesTo examine the associaiton between environmental measures and brain volumes and its potential mediators. Study designThis was a prospective study. MethodsOur analysis included 34,454 participants (53.4% females) aged 40–73 years at baseline (between 2006 and 2010) from the UK Biobank. Brain volumes were measured using magnetic resonance imaging between 2014 and 2019. ResultsGreater proximity to greenspace buffered at 1000 m at baseline was associated with larger volumes of total brain measured 8.8 years after baseline assessment (standardized β (95% CI) for each 10% increment in coverage: 0.013(0.005,0.020)), grey matter (0.013(0.006,0.020)), and white matter (0.011(0.004,0.017)) after adjustment for covariates and air pollution. The corresponding numbers for natural environment buffered at 1000 m were 0.010 (0.004,0.017), 0.009 (0.004,0.015), and 0.010 (0.004,0.016), respectively. Similar results were observed for greenspace and natural environment buffered at 300 m. The strongest mediator for the association between greenspace buffered at 1000 m and total brain volume was smoking (percentage (95% CI) of total variance explained: 7.9% (5.5–11.4%)) followed by mean sphered cell volume (3.3% (1.8–5.8%)), vitamin D (2.9% (1.6–5.1%)), and creatinine in blood (2.7% (1.6–4.7%)). Significant mediators combined explained 18.5% (13.2–25.3%) of the association with total brain volume and 32.9% (95% CI: 22.3–45.7%) of the association with grey matter volume. The percentage (95% CI) of the association between natural environment and total brain volume explained by significant mediators combined was 20.6% (14.7–28.1%)). ConclusionsHigher coverage percentage of greenspace and environment may benefit brain health by promoting healthy lifestyle and improving biomarkers including vitamin D and red blood cell indices.

A new snow cover mapping algorithm for Chinese geostationary meteorological satellite FY-4A AGRI data

ABSTRACT China’s second generation of geostationary meteorological satellites Fengyun-4 (FY-4) are equipped with the Advanced Geosynchronous Radiation Imager (AGRI) which has the advantages of large number of spectral bands and high temporal resolution. To fully leverage these features, a new snow cover (SC) mapping algorithm was proposed, which firstly derives SC map from a single scene image and then combines multi-temporal SC results within one day into a daily SC composite. The novelty of the proposed algorithm includes the utilization of small spatial and temporal divisions to avoid the use of complex kernel-driven models for the correction of bidirectional effects of surface reflectance and a novel framework to merge multi-temporal SC maps by weighting the solar illumination conditions. The SC results were validated against in-situ snow depth measurements, Landsat 8 derived SC data and MODIS SC products. Results indicate that merging multi-temporal SC data can reduce cloud obscuration with the average daily cloud coverage percentage decreasing from about 47.03% for single scene to 35.62% for merged one and slightly improve snow detection accuracy. The overall accuracy (OA) ranges from 95.00% to 96.19%, and the F-score (FS) varies from 77.78% to 87.14% when compared to different reference data, suggesting an overall good performance.

Rubber plantations are impermeable to an avian understory specialist in Sri Lanka

BackgroundUnderstanding how landscape characteristics affect animal movement is essential for conservation in human-dominated habitats. A fundamental question is how monoculture agroforests, including rubber and tea plantations, affect wildlife and its movement. Experimental translocations represent an important technique to assess animals’ habitat selection while moving through agricultural matrices, especially when complemented with observations of birds’ natural movements, and with “control” translocations, in which birds are moved within their natural habitat such as forest. Yet, experimental translocations have been little used for birds outside the Western Hemisphere.MethodsWe conducted experimental translocations and home-range measurements on an understory forest specialist, Brown-capped Babbler (BCBA, Pellorneum fuscocapillus), and a forest generalist, Tickell’s Blue Flycatcher (TBFL, Cyornis tickelliae). These species were studied in three rubber plantations, which also included some open areas mostly planted with tea, and in three forest reserves of Sri Lanka.ResultsFour of the five BCBAs translocated within disturbed habitats (rubber plantations) could not return to their capture locations. However, all four individuals within undisturbed habitats (forest reserves) successfully returned to their point of origin within 10.5 daytime hours. In contrast, all TBFLs returned to their capture locations in both disturbed (n = 7) and undisturbed habitats (n = 3) within 11.3 daytime hours. A Cox-proportional survival model demonstrated that the percentage of rubber cover decreased return time, similar to the effect of open-area cover. The home range surveys (n = 13 for BCBA, n = 10 for TBFL) revealed that very little of the birds’ natural home-ranges was covered by rubber (0.2% for BCBA, 13.1% for TBFL at 50% Kernel Density Estimates KDE). Home range size for BCBA was approximately half the size in disturbed habitats compared to undisturbed ones, although there was no significant difference between habitats for TBFL.ConclusionsWe conclude that rubber plantations can be impermeable to understory habitat specialist birds, and even generalist species may avoid them long-term. Our findings highlight the potential utility of strips of native vegetation, particularly those featuring understory layers, as corridors to facilitate the movement of forest specialists in landscapes dominated by rubber plantations and other types of disturbed habitats.

The Inter‐Model Uncertainty of Projected Precipitation Change in Northern China: The Modulating Role of North Atlantic Sea Surface Temperature

AbstractPrecipitation changes in northern China are projected to increase in the Coupled Model Inter‐comparison Project Phase 6 (CMIP6) multi‐model ensemble. However, these projections are accompanied by notable inter‐model uncertainty, and the sources of this uncertainty remain largely unexplored. By analyzing 30 CMIP6 models, this research explores the source of inter‐model uncertainty in projected precipitation change and reveals the fundamental mechanism driving uncertainty spread. Following the empirical orthogonal function of inter‐model projected precipitation change, the leading mode displays a seesaw spatial pattern between northwest and north China. This phenomenon predominantly stems from the inter‐model divergence of projected sea surface temperature (SST) warming in the North Atlantic. Further scrutinizing the ocean mixed layer heat budget, we discover that the combined effect of surface sensible heat flux, net surface shortwave radiation flux, and ocean heat transport convergence influences heat flux and SST change of North Atlantic. The multi‐model projections indicate that localized increases in solar radiation and heat convergence warm sea surface, raising SST and initiating convective motion. This convective motion subsequently transforms the 200 hPa teleconnection wave train, leading to an anti‐phase pattern over northern China. This wave pattern modulates total cloud cover percentage, influences surface upward latent heat flux, and adjusts the top of atmosphere outgoing longwave radiation, collectively resulting in the seesaw pattern. Our study underscores the pivotal role of inter‐model disparities in North Atlantic SST warming projection, which is a primary driver of precipitation uncertainty in northern China. These insights offer an essential foundation for refining and diminishing inter‐model uncertainty.