Dusty Areas Research Articles

A study on chronic obstructive pulmonary disease and its determinants among underground coal mine workers in Bankola area, Durgapur, West Bengal

Background: Chronic obstructive pulmonary disease is a leading cause of morbidity and mortality worldwide that effectuate an economic and social burden that is both considerable and progressive. Mortality from respiratory disease remains an important occupational hazard among coal miners. Inhalation of coal mine dust is known to cause several respiratory diseases including COPD. The current study aimed to estimate the prevalence of COPD among coal miners and to find out the predictors of the same in Bankola Area, Durgapur, West Bengal. Methods: A cross-sectional study was conducted among 315 coal miners selected by simple random sampling from the list of mines in Bankola Area, Durgapur, West Bengal. The required data was collected by face-to-face interview with the help of a predesigned pretested questionnaire and subsequently clinical examination along with spirometry in an eligible subset of population. Data thus collected had been analysed by SPSS 16.0 version. Results: Prevalence of COPD among mines was found to be 11.7%. Most of the miners showing obstructive pattern, had Grade 2 severity of airflow limitation (43.2%) whereas 8.2% had Grade 4 severity. Multivariate analyses revealed that miners who were smoking for more than 20 years, working in highly dusty areas and those who were working at coal face had higher odds of developing COPD. Conclusions: Addressing substance use as well as improvement in working environment including use of personal protective equipment can holistically lead to better respiratory health of the miners.

Micron-Smooth, Robust Hydrophobic Coating for Photovoltaic Panel Surfaces in Arid and Dusty Areas

Photovoltaic (PV) power generation is a clean energy source, and the accumulation of ash on the surface of PV panels can lead to power loss. For polycrystalline PV panels, self-cleaning film is an economical and excellent solution. However, the main reasons why self-cleaning coatings are currently difficult to use on a large scale are poor durability and low transparency. It is a challenge to improve the durability and transparency of self-cleaning thin films for PV panel surface against ash accumulation. Therefore, in this paper, a resin composite film containing modified silica components was designed and synthesized, mainly by the organic/inorganic composite method. A transparent hydrophobic coating with nano-micro planar structures was constructed, which primarily relies on the hydrophobic properties of the compound itself to build the hydrophobic oleophobic coating. The layer has a micrometer-scale smooth surface structure and high transparency, with a 0.69% increase in light transmittance compared with uncoated glass, and the durability is good. It is mainly applied to the surface of photovoltaic devices, which can alleviate the dust accumulation problem of photovoltaic panels in arid, high-temperature, and dusty areas and reduce the maintenance cost of them.

Effect of Dust Emitted from Al-Kufa Cement Factory on some Indicators of Vegetative Growth of Wheat Plants

A field study was conducted in the winter of 2022–2023 to determine the effect of Al-Kufa Cement Factory (CKD) dust on some soils in the plant’s neighboring areas on some botanical indicators of the wheat crop grown there by comparing them to vegetative growth indicators. The study was conducted on four locations surrounding Al-Kufa Cement Factory, three of which were southeast of the plant and under the influence of the cement factory dust with a sandy loam texture, and the fourth was northwest of the factory and not affected by the factory dust (comparison) with a sandy location texture. Some physical features of these sites have been measured. Seven replicates were used to measure plant height, number of leaves, number of branches, wheat production, and vegetative growth. The results showed that the dust factor had a significant effect on the studied vegetative growth indicators of wheat plants, including plant height, which increased with the dust factor, as the average of the studied grade in dust-affected locations was (89.73) cm. plant-1 and (74.13) cm. plant-1 in the unaffected location. According to the data, the average number of plant branches in dust-affected areas was (3.86-3.26) more than in unaffected areas. respectively plant-1 Leaf number attributes are the same. The average number of leaves in cement industry dust-affected areas increased to 10.73. Plant-1. The average of the same grade in the industrial dust-free area was 8.43 leaves. Plant-1, and the dust component increased the edge weight of wheat yield by 1.78 g. Plant-1 in dusty areas and (1.42) gm. Unaffected Plant-1, In the dust-affected area, the vegetative group’s dry weight increased with the dust factor, reaching (5.56) g. (4.43) g and plant-1. Unaffected plant-1.

Performance evaluation of solar panels under different dust accumulation conditions using thermography: focusing on PV temperature variation

Degradation performance of photovoltaic modules (SPV) by real conditions has become increasingly problematic. In dusty areas, dust accumulation is one of the main concerns that may cause a significant determination of SPV efficiency. In the current study, the effect of four dust-accumulated densities of 6, 12, 18, and 24 g/m2 have been investigated in outdoor conditions in Cairo, Egypt. The performance evaluation of SPV modules in the form of front and backside temperatures of the SPV module has been evaluated in addition to current, voltage, power, and efficiency of the SPV modules. The results showed that, as compared with a clean SPV module, with increasing dust density from 6 to 24 g/m2 the frontside temperature of SPV modules were lower by 6–8 ℃. While their backside temperatures were found to be higher by 2–6 ℃. In addition, the difference between the backside and frontside temperatures of the SPV module ranged from 5 to 14 ℃ for dust modules as compared with 3 ℃ for the clean SPV module. The output power and efficiency of dusty SPV modules were found to be lower by 6–45% and 13–38%, respectively as compared with clean SPV module. The results clearly showed the importance of properly maintaining and servicing the SPV modules to avoid their degradation by dust accumulated.

Self-reported respiratory health symptoms and respiratory protection behaviors of young adult hog producers in the United States.

In this study, we evaluated self-reported respiratory symptoms during agricultural work, respiratory protection use and experience, and perceived value of receiving respirators using Gear Up for Ag Health and Safety Program™ pre- and post-surveys from 703 to 212 young adult hog producers in the United States. To our knowledge, this is one of the most extensive survey data sets on self-reported respiratory symptoms and respiratory protection behaviors of collegiate-aged young adults working in USlivestock production. About one-third (37%) of young adult hog producers stated that they have experienced cough, shortness of breath, fever, and chills after working in dusty areas on the farm. Most (76.2%) stated that they were already "always"or "sometimes"wearing filtering facepiece (N95-style) respirators, even before participating in an outreach program. About one-third (30%) reported experience wearing a cartridge-style respirator but only 5% reported having been fit-tested for a respirator. Young adult male producers were significantly more likely to report use of both respirator types when compared to females, both before and after the program. Male producers were also more likely than females to engage in high-risk farm tasks where respirators are recommended, such as cleaning out grain bins and mixing or grinding feed. Following an educational program, males and females reported using the respirators that they received at similar rates, and 20% of overall participants purchased additional respiratory protection. The study found that young adult hog producers in postsecondary education are already wearing respirators with some frequency and at rates higher than previously reported by agricultural workers. More research is needed to make effective task-based respirator-use recommendations and investigate some significant gender differences among young adult hog producers observed in this study.

Dust cycle, soiling effect and optimum cleaning schedule for PV modules in Iran: A long-term multi-criteria analysis

Mineral dust has a great effect on the performance of solar power plants not only by absorbing and scattering solar radiation, but also due to soiling effects. The aim of the present study is to investigate the characteristics of dust in Iran using the Modern-Era-Retrospective-Analysis for Research and Applications in 2000–2019. In this assessment, radiation effects, dust emission and deposition rate in Iran were investigated from the aspects of seasonal changes and trends. Then, the effect of soiling in a 100 MW power plant in a twenty-year period in different regions of Iran was investigated. Finally, 15 cleaning scenarios were examined from three technical, economic, and environmental perspectives, and the most appropriate scenario was selected in each region of Iran using the multi-criteria decision-making method (MCDM). The evaluation showed the most dust emission rate is occurred in the southwestern Iran. In addition, rainfall has only been able to reduce the soiling effects in the western part of Iran to some extent, but it cannot be a suitable economic solution to reduce this effect. With dust soiling effect, the Levelized cost of energy (LCOE) varies from 100 to 270$/MWh. However, cleaning can reduce LCOE to 50$/MWh and is vital solution to develop solar energy in dusty areas. The results of MCDM also showed that weekly and semi-weekly automatic cleaning are the most suitable periods in Iranian solar plants.

Simulation of the Ozone Concentration in Three Regions of Xinjiang, China, Using a Genetic Algorithm-Optimized BP Neural Network Model

Accurate ozone concentration simulation can provide a health reference for people’s daily lives. Simulating ozone concentrations is a complex task because near-surface ozone production is determined by a combination of volatile organic compounds (VOCs) and NOx emissions, atmospheric photochemical reactions, and meteorological factors. In this study, we applied a genetic algorithm-optimized back propagation (GA-BP) neural network, multiple linear regression (MLR), BP neural network, random forest (RF) algorithm, and long short-term memory network (LSTM) to model ozone concentrations in three regions of Xinjiang, China (Urumqi, Hotan, and Dushanzi districts) for the first time by inputting wind speed, humidity, visibility, temperature, and wind direction. The results showed that the average relative errors of the model simulations in the Urumqi, Hotan, and Dushanzi districts were BP (61%, 14%, and 16%), MLR (97%, 14%, and 23%), RF (39%, 11%, and 14%), LSTM (50%, 12%, and 16%), and GA-BP (16%, 4%, and 6%) and that the significance coefficients R2 were BP (0.73, 0.65, and 0.83), MLR (0.68, 0.62, and 0.74), RF (0.85, 0.80, and 0.88), LSTM (0.78, 0.74, and 0.85), and GA-BP (0.92, 0.93, and 0.94), respectively, with the simulated values of GA-BP being the closest to the true values. The GA-BP model results showed that among the 100 samples with the same wind speed, humidity, visibility, temperature, and wind direction data, the highest simulated ozone concentrations in the Urumqi, Hotan, and Dushanzi districts were 173.5 μg/m3, 114.3 μg/m3, and 228.4 μg/m3, respectively. The results provide a theoretical basis for the effective control of regional ozone pollution in urban areas (Urumqi), dusty areas (Hotan), and industrial areas (Dushanzi) in Xinjiang.

Urban Resilience in Africa: A Study of Land-Use Stresses on the Urban Environment in the GreaterAccra Metropolitan Area, Ghana

The Greater Accra Metropolitan Area of Ghana is experiencing rapid urbanisation at the expense of the environment, with substantial pollution compromising the area's resilience. This article examines the spatial dynamics of pollution from land use in the area and its health-related impacts. Drawing on a desk review of the literature and a transdisciplinary empirical approach, this study employed participatory mapping and qualitative methods of analysis to examine the extent to which the Greater Accra Metropolitan Area is building resilience in the face of increasing environmental pollution induced by land use. The researchers found spatial variations in the phenomenon, i.e. community-specific land-use pollution and general land-use pollution. Community-specific land-use pollution comes from dust and fumes, quarries and sand weaning, historical preservations, and transport corridors. General land-use pollution found across the study area related to dusty areas, noise from markets and churches, contamination of water bodies, solid and liquid waste, as well as excessive spillage of lubricants and carbon monoxide from car engines – all of which poses a threat to human health. Although both local and successive national governments have initiated different actions and platforms to mitigate pollution from land use and its health impacts, Ghana must work harder to build a framework of more sustainable and robust urban resilience.

Effect of Temperature and Velocity on Microparticle Erosion/Deposition into Environmental-Barrier-Coated Ceramic Matrix Composite for Aeroengines

Abstract Ceramic matrix composites (CMCs), especially SiC/SiC, have garnered significant attention owing to their remarkable mechanical properties at higher temperatures. For the protection of the substrate from oxidation, the SiC/SiC CMCs inherently require environmental barrier coating (EBC). Because aeroengines must function under a wide range of conditions and environments, the coated CMC must be sufficiently resistant to various damage modes. Among these, the effect of microparticles is one of the limiting factors for the durability and performance of components, particularly when the engine is operated in dusty areas. The main goal of this experimental research is to investigate and determine the surface damage behavior of the coated CMC caused by micro-sand particles. The data were surveyed across a fairly broad range of exposed temperatures and velocities, and covered conditions relevant to advanced hot section designs. In the experiments, silica or alumina sand entrained in the gas stream was jet-blasted from the nozzle and then impinged on the target CMC + EBC coupon. Owing to the broad testing range, the damage mode and extent of damage varied considerably by condition. The obtained data were then reorganized and compared with several previously proposed particle impact models. This is to first understand and obtain a complete picture of all the probable consequences in the expected design and off-design conditions and, second, to determine the validity of, and deviations from the conventional modeling with the present CMC + EBC material, which will be useful in the next component design phase.

Effects of dust on the performance of solar panels – a review update from 2015–2020

Solar power plays a significant role in the contribution of energy worldwide. The performance of solar panels mainly depends upon geographical and environmental factors. Dust is an important well known ecological factor that significantly impacts the performance of solar panels in achieving the overall target of power production by renewable sources. Study about the performance of solar panels under the influence of dust particles becomes more effective when these are to be worked out in hot and dusty areas. The current goal of this review article is to provide the impact of dust particles on the performance of solar panels. To fulfil this goal, the researcher's contribution is updated in minor for 2015 to 2018 and signed for 2019 and 2020.The current authors of this review article also recommended the adoption of a modern cleaning technique for PV modules, which would save time because it could be operated away from the PV modules.

Selection and evaluation of suitable tree species in dry and dusty mining areas of Northwest China

To select drought-resistant and dust-tolerant native species suitable for use in the rehabilitation of major coal bases in northwest China, nine tree species were identified for growth rates, biomass, harm index, and physiological indices under drought and high dust stress conditions. The results showed that, in the dust resistance index system, the order was Caragana korshinskii > Amorpha fruticosa > Sabina vulgaris > Hedysarum scoparium > Tamarix chinensis > Ammopiptanthus mongolicus > Ulmus pumila > Caryopteris mongholica > Elaeagnus angustifolia. In a comprehensive drought and dust resistance index system, 14 indices (such as shoot length, stomatal conductance, and peroxidase) had the larger weight indices. The drought and dust resistance order of the tree species was Caragana korshinskii > Ulmus pumila > Amorpha fruticosa > Sabina vulgaris > Caryopteris mongholica > Ammopiptanthus mongolicus > Hedysarum scoparium > Tamarix chinensis > Elaeagnus angustifolia. This study provides effective strategies and references for selecting suitable tree species for arid mining sites in China, and also for the revegetation of coal mining sites worldwide.

Numerical modeling of atmospheric pollution in the approaches of random selection of discrete dusting sites and interval distribution of dust size

The results of numerical simulation of atmospheric pollution in Apatity are presented with variations in the dusting area of discrete spatially spaced areas selected randomly and the wind flow velocity. CFD modeling in the volumetric formulation was performed using the COMSOL program. To calculate the aerodynamic characteristics, an incompressible fluid approximation was used using the standard ( k -ε) turbulence model. The process of fine dust propagation is modeled by numerical solution of the convective-diffusion impurity transfer equation taking into account the deposition rate. Numerical experiments (with a total number of more than 1,400) were carried out with a variation of the wind flow velocity from 5 to 23 m/s and a dusting area from 2 to 10 ha with a random selection of 20 discrete sites. Dynamic velocity distributions for specific areas of dusting, interval and total spatial distributions of dust pollution (dust particles with a diameter from 0 to 70 microns in increments of 10 microns) are obtained. The peculiarities of the influence on the levels of atmospheric pollution of specific areas of Apatity depending on the location of dusty areas on the surface of the beach of the tailings dump are noted. The calculated levels of atmospheric pollution in the center of Apatity averaged by the number of combinations of dusting sites are analyzed and generalized to functional dependencies. The calculated dependences of the dust concentration on the dusting area at a fixed wind speed are described by linear functions. The dependence of the dust concentration on the wind flow velocity at a fixed dusting area can be approximated by a power function. The generalized functional dependence makes it possible to predict the dust concentration in Apatity depending on the dusting area of randomly selected discrete areas on the surface of the tailings dump and the wind flow velocity. The obtained dependence permits to make a forecast of the critical dusting area at which the level of atmospheric pollution reaches the maximum permissible concentrations, depending on the speed of the wind flow.

Методи обліку чисельності гризунів

This is a republication of the methodological review originally published in 1957, which has been important for the organization of local and regional studies of the mammal fauna, particularly in the identification of species composition and estimates of the relative abundance of small (mouse-like) rodents. The present publication is accompanied by an editorial foreword and contains seven chapters. The first three are titled ‘Rodents as objects of census and monitoring,’ ‘Census of rodents and its components,’ and ‘Census of rodents in the field with attention to relative and absolute census.’ The section on relative census includes such topics as ‘Census by biological indicators,’ ‘Census by analysis of pellets and excrements of predators of mice,’ ‘Census by counting burrows (holes),’ and ‘Cenus on trap lines.’ The section on absolute census includes parts such as ‘Census by complete excavation of burrows and complete capture of their population’ and ‘Census of rodents in various kinds of haystack.’ The other sections are ‘Census of forest-dwelling rodents,’ ‘Census of rats and mice in human settlements’ (includes three parts: the method of dusty areas, the method of trial bait, and the method of almost complete capture), ‘Methods of combating certain species of harmful rodents’ (abridged), ‘Controlling methods of some species of harmful rodents’ (abridged), and ‘Collection and transfer to specialists of rodent materials for scientific purposes.’

Modelling of the Chemical Halo of Dust Pollution Migration in Loparite Ore Tailings Storage Facilities

The article presents a study of the environmental impact of dusting tailing dumps of rare-metal ore dressing in the Murmansk region of Russia. The purpose of the study was to establish patterns in the atmochemical halo migration of the dust pollution of loparite ore dressing tailings. The geotechnical characteristics and material composition of the tailings material have been investigated. Potentially dusty areas identified. Models of dispersion of inorganic dust under different meteorological scenarios are constructed: at low wind load, normal and unfavorable meteorological conditions. The modeling of the spread of pollutants in the area exposed to dust at the storage site was carried out in the program for modeling atmospheric pollution Ecolog-4.60. Calculation of the dispersion of inorganic dust containing 20–70% SiO2 showed that the atmochemical halo of tailings dust pollution spreads over tens of kilometers, and already at a wind speed of about 8 m/s, the concentration of suspended solids at the border of the enterprise sanitary protection zone exceeds the maximum one-time maximum permissible concentration is 3–3.3 times, and under unfavorable meteorological conditions—Dusting reaches the boundaries of the residential area (inhabited locality Revda), located in the north-west of the enterprise, and exceeds the MPCm.o. 1.5 times.

Cleaning of Solar Panel using Automation Technique

Solar energy is considered to be one of the best major renewable energy resources to generate and meet the electrical energy demand of the entire globe. Solar PV modules produce electricity by collecting the sunlight. solar PV modules are generally employed in dusty environmental areas like in India, which comes under the tropical region. Various dust particles present in the tropical region, so the dust particles are accumulated on the surface of the solar panel. Therefore, the incident light can be blocked. As a result, the module power capacity can be reduced. If the panel not cleaned properly the power output become reduced by 50%. To increase the power output an automatic cleaning mechanism has been designed. This automatic cleaning mechanism not only senses the dust accumulated on the solar panel but also clean the solar PV module automatically. This solar cleaning mechanism is mainly implemented using PIC 16F 1527 microcontroller, which mainly controls the stepper motor, Air compressor and water pump. The dust can be cleaned by the gantry which is mainly driven by the stepper motor. The gantry has mist nozzles which create pressurized air and water to clean the solar panel effectively. The cleaning can be done by air and water depending upon the dust accumulated on the solar panel. Index Terms: solar panel; micro-controller; stepper motor; dust particles.

Correlation between Telomere Length and Chronic Obstructive Pulmonary Disease-Related Phenotypes: Results from the Chronic Obstructive Pulmonary Disease in Dusty Areas (CODA) Cohort.

BackgroundChronic obstructive pulmonary disease (COPD) is a common chronic respiratory disease with increased prevalence in the elderly. Telomeres are repetitive DNA sequences found at the end of the chromosome, which progressively shorten as cells divide. Telomere length is known to be a molecular marker of aging. This study aimed to assess the relationship between telomere length and the risk of COPD, lung function, respiratory symptoms, and emphysema index in Chronic Obstructive Pulmonary Disease in Dusty Areas (CODA) cohort.MethodsWe extracted DNA from the peripheral blood samples of 446 participants, including 285 COPD patients and 161 control participants. We measured absolute telomere length using quantitative real-time polymerase chain reaction. All participants underwent spirometry and quantitative computed tomography scan. Questionnaires assessing respiratory symptoms and the COPD Assessment Test was filled by all the participants.ResultsThe mean age of participants at the baseline visit was 72.5±7.1 years. Males accounted for 72% (321 participants) of the all participants. The mean telomere length was lower in the COPD group compared to the non-COPD group (COPD, 16.81±13.90 kb; non-COPD, 21.97±14.43 kb). In COPD patients, 112 (75.7%) were distributed as tertile 1 (shortest), 91 (61.1%) as tertile 2 and 82 (55%) as tertile 3 (longest). We did not find significant associations between telomere length and lung function, exacerbation, airway wall thickness, and emphysema index after adjusting for sex, age, and smoking status.ConclusionIn this study, the relationship between various COPD phenotypes and telomere length was analyzed, but no significant statistical associations were shown.

Association between Long-Term Exposure to PM2.5 and Lung Imaging Phenotype in CODA Cohort

Background and Aims: Ambient particulate matter (PM) is causing respiratory symptoms of individuals at all ages and reducing their lung functions. These individuals could develop chronic pulmonary disease. Recent studies have shown that short-term exposure to PM affects acute exacerbation of respiratory disease. However, evidence about the association between long-term exposure and progression of respiratory diseases remains insufficient. The purpose of this study was to examine the association between long-term exposure of air pollution (PM2.5) and the effect on lung imaging phenotype in dust-exposed Korean adults living near cement factories. Methods: We conducted a cross-sectional analysis on the Chronic Obstructive Pulmonary Disease (COPD) in Dusty Areas (CODA) cohort, which was recruited from 2012 to 2014. Emphysema index and mean wall area were measured using an in-house software program developed by the Korean obstructive lung disease study group based on chest CT scan. A satellite-based model was used to estimate the long-term PM2.5 concentration at each participant’s address. Results: Of 504 eligible participants, 400 participants were analyzed. Their mean age was 71.7 years. Most participants were men (N = 301, 75.3%). The emphysema index of the whole group was 6.63 ± 0.70, and the mean wall area was 68.8 ± 5.2. Image measurement and PM2.5 concentration showed no significant difference in the whole group; however, in the group of subjects with normal lung function, there were significant associations between long-term PM2.5 exposure and emphysema index measurement: 1-year (ß = 0.758, p = 0.021), 3-year (ß = 0.629, p = 0.038), and 5-year (ß = 0.544, p = 0.045). There was no significant association between long-term PM2.5 exposure and mean wall area measurement: 1-year (ß = −0.389, p = 0.832), 3-year (ß = −3.677, p = 0.170), and 5-year (ß = −3.769, p = 0.124). Conclusions: This study suggests that long-term exposure of PM2.5 may affect the emphysematous change in patients with normal lung functions.

To study the prevalence & clino-mycological profile of Otomycosis in Saurashtra & Kutch region of Gujarat

Otomycosis is a superficial, sub-acute or chronic infection of the external auditory canal. It is worldwide in distribution with a higher prevalence in the hot, humid, and dusty areas of the tropics and subtropics. A wide variety of fungi can cause Otomycosis.To determine the demographic profile & spectrum of fungi involved in Otomycosis in saurashtra & Kutch region of Gujarat. A retrospective study of 101 clinically suspected cases of otomycosis were conducted. The sample are taken by two sterile cotton swabs comprised of secretions, pus and debris from the external auditory canal. Direct microscopic examination by 10% KOH, Gram stain & cuiture on medium was done. Identification of fungi done by lacto phenol cotton blue, GERM TUBE TEST & growth on CORNMEAL AGAR and Hichrome Media ysed for species identification. Out of 101 cases, 76(75.24%) were Culture Positive and 74(73.26%) were KOH positive. Out of 74 KOH positive, 65(87.83%) cases were culture positive. Predominantly males (52.6%) were affected. The most affected age group is 31-40 yrs of age (23.68%). (52.63%) was the predominant species isolated followed by Aspergillus flavus (36.84%), . . The disease is predominantly unilateral.Otomycosis should be suspected clinically and should be confirmed by laboratory diagnosis to prevent unnecessary use of antibiotics & there by antibiotic resistance. Mycological diagnosis is important to differentiated from bacterial infection, since symptoms (pruritus, otalgia, otorrhea and hypacusis) are not specific.

From dust till drowned: the Holocene landscape development at Norderney, East Frisian Islands

AbstractWithin the multidisciplinary WASA project, 160 cores up to 5 m long have been obtained from the back-barrier area and off the coast of the East Frisian island of Norderney. Thirty-seven contained basal peats on top of Pleistocene sands of the formerGeestand 10 of them also had intercalated peats. Based on 100 acclerator mass spectrometry (AMS)14C dates and analyses of botanical as well as zoological remains from the peats, lagoonal sediments and the underlying sands, a variety of distinct habitats have been reconstructed. On the relatively steep slopes north of the present island, a swampy vegetation fringe several kilometres wide with carrs of alder (Alnus glutinosa) moved in front of the rising sea upwards of theGeestas it existed then until roughly 6 ka, when the sea level reached the current back-barrier region of Norderney at around −6 m NHN (German ordnance datum). From then on for nearly 4000 years a changing landscape with a mosaic of freshwater lakes and fens existed within this area. It was characterised by various stands ofCladium mariscus(fen sedge), alternating with brackish reed beds withPhragmites australis(common reed) and salt meadows withAster tripolium(sea aster),Triglochin maritima(sea arrowgrass),Juncus gerardii(saltmarsh rush) as well as mudflats withSalicornia europaea(common glasswort). As far as shown by our cores, this highly diverse, and for humans potentially attractive landscape was at least some 4 km wide and followed the coast for about 10 km. Before the rising sea caused diversification of habitats, wet heath as well as dry and dusty sand areas existed. In the course of time, parts of the wet heath turned into raisedSphagnumbogs under an oceanic precipitation regime before this diverse landscape was drowned by the rising sea and finally covered by marine sediments, while the earlier sediments and peats were partly eroded and redeposited.

Preparation and characterization of an eco-friendly dust suppression and sand-fixation liquid mulching film

An eco-friendly dust suppression and sand-fixation liquid mulching film was prepared via a facile secondary spraying process in this work. Water polyurethane (WPU) was blended with dissolved humic acid (HA) firstly, and then the blend solutions (HWPU) were sprayed on the surface of cationic starch (CS) / sodium lignosulfonate (LS) film to synthesize the liquid mulching film (CLS-HWPU). The effects of liquid mulching film composition on mechanical properties in dry and wet states were investigated. The results showed that the optimal composition of liquid mulching film was: 3% (CS), 0.9 % (LS), 1.5 % (glycerol), 2% (HA), and 30 % (WPU). The CLS-HWPU liquid mulching films were characterized in terms of light transmittance, degradation performance test, contact angle test, scanning electron microscopy (SEM), total reflectance-Fourier transform infrared spectrometer (ATR-FTIR), thermo gravimetric analysis (TGA), and erosion resistance test. The results indicated that the CLS-HWPU film had good UV resistance, thermal stability, anti-erosion, and biodegradation. The CLS-HWPU film meets the demand of dust suppression and sand-fixation in dusty areas and desertification environments, which opens a new application field for liquid mulching film with high safety and environmental protection.