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For behavioural ecologists who study nocturnal animals, recording behaviour at night is essential but expensive. Added difficulties arise when filming minifauna, as the most popular methods of recording nocturnal behaviour (i.e. trail cameras) function at a minimum focal distance of 3 m or greater. Infrared (IR)-sensitive camcorders can provide excellent footage of smaller animals at a shorter distance but can cost over $1000 USD. In addition, these pricey cameras rarely stand up to the elements in the field and are also limited by short battery life. Here, we provide a field-tested method to record nocturnal behaviour, of both small and large animals, at a fraction of the cost. We have had great success modifying inexpensive, commercially available action cameras (GoPro Hero4 camcorders) to be IR sensitive, powering these units with cellular phone power banks and continuously recording behaviour overnight while using an array of a dozen cameras. In total, all components of a recording kit are available for under $150 USD at the time of this writing (February 2024) and can be easily assembled using the guidelines described in the present paper. This paper provides researchers with an economical strategy to record continuous behaviour in nocturnally active animals, with a kit that outperforms most currently available camera options across various contexts. While the proposed kit may provide the greatest benefits to researchers studying minifauna, the recording set-up can be easily and cheaply adapted to capture nocturnal megafauna behaviour. As such, we hope these methods increase the accessibility of science and expand the experimental toolkits of biologists interested in the fascinating, but much understudied, world of nocturnal animal behaviour. • Traditional infrared-sensitive camcorders are expensive and impractical for fieldwork. • We present an economical, field-tested solution: modified commercial action cameras. • We give a step-by-step guide, detailing how to configure a complete recording kit. • Benefits include long recording times, portability, HD and high-speed recording. • We hope our kit makes scientifically exploring nocturnal behaviour more accessible. [ABSTRACT FROM AUTHOR]

The numerical simulation of wind-induced snowdrift often employs a one-way coupled scheme that neglects the interaction between moving snow particles and turbulent wind. However, this approach can result in significant errors when the mass concentration of snowdrift near the snow surface is high. To address this issue, a modified two-way coupled scheme for simulating three-dimensional wind-induced snowdrift was developed. This scheme reasonably considers the interaction between snow particles and turbulent wind and introduces a double-loop nested framework. To illustrate the effectiveness of this method, a simulation was conducted for large-scale wind and snow fields on the roof of a terminal building in northwest China. The results were compared with field observation data of snow depth, demonstrating the applicability and superiority of the proposed method. The modified two-way coupled scheme was shown to provide a more accurate simulation of wind-induced snowdrift compared to the one-way coupled scheme. Based on this improved accuracy, predictions of wind-induced snow redistribution on the building roof were made, considering a 100-year return period for wind and snow loads. These predictions are crucial for the safety design of long-span roof structures in cold regions. [ABSTRACT FROM AUTHOR]

Competition is one of the most critical factors affecting animal behaviors. Aggressive interactions are central to acquiring resources or mating partners. Agonistic behavior is more common among males than females. Although laboratory observations of these behaviors give detailed descriptions under controlled conditions, field observations without human intervention are required because those supply information that provides insights into their function. In this paper, we report on the field observation and auxiliary laboratory experiments of male–male agonistic behavior of a wood‐feeding cockroach, Panesthia angustipennis, and discuss its strategy. In the field, a male pushed the opponent with the horn on the pronotum out of a gap between two logs, under which a female was. After pushing, the male repeatedly returned to a place close to the female, even if it did not subdue the opponent entirely. It suggests that the male–male agonistic behavior in P. angustipennis has both attack and avoidance. The bout was repeated as the ejected male reapproached the male. In contrast, the inferior male often escaped in the laboratory recording after field observation. Keeping the fighting experience for several days may contribute to the males avoiding a "losing battle." This study significantly enhances our understanding of the mating strategy of P. angustipennis through male–male agonistic behavior and provides possibilities for its cognitive aspects from the fighting experience. [ABSTRACT FROM AUTHOR]

Cleaning symbiosis of the bluestreak cleaner wrasse, Labroides dimidiatus (Labridae), is a well-known example of mutualism in coral reefs. The cleaner wrasse is characterized by its bluish body colour with black stripes, and the false cleanerfish, Aspidontus taeniatus (Blenniidae), mimics those characteristics precisely. Cleaner fish mimicry is believed to evolve as an aggressive mimicry to bite the fins of deceived fishes; however, protective mimicry to reduce predation risk has not been examined sufficiently. Here, we tested the effect of protective mimicry through field observations and aquarium experiments. Field observations revealed that false cleanerfish were occasionally attacked by piscivorous lizardfishes (Synodontidae). In the aquarium experiments, ambushing predators, the honeycomb grouper, Epinephelus merra (Serranidae), which did not show predatory behaviour to false cleanerfish in the field, attacked the cleaner wrasse (model), the false cleanerfish (mimic), and the lance blenny, Aspidontus dussumieri (non-mimic). When a shelter was provided in the tank, the false cleanerfish and the lance blenny immediately hid inside the shelter for a considerable duration to escape from the predator. These results suggest that cleaner fish coloration does not always decrease predation risks, and our conclusions support the possibility that this mimicry evolved primarily as aggressive mimicry. [ABSTRACT FROM AUTHOR]

When resources such as mates or mating sites are limited, selection drives the evolution of complex and frequently violent fighting behaviour. Contest outcome is determined by an individual's resource holding potential (RHP) in comparison to that of their opponent. During contests individuals may assess only their own RHP, or they may mutually assess both their own and their opponent's RHP to determine the effort they allocate to a contest. Male giraffe weevils (Lasiorhynchus barbicornis) bear an elongated rostrum used as a weapon during intense fights over access to females. We used sequential analysis to target the fine-scale structure of contests and phases of contest escalation to determine the assessment strategy used by rival male giraffe weevils in the wild. We found significant non-random temporal structure in behavioural transitions in all transition matrices, and winner and loser transition matrices were significantly different. Contest de-escalation was extremely rare compared to escalation and winners and losers used very different behaviours during contests overall. This study provides support for the sequential assessment model of mutual assessment by male giraffe weevils during competitive interactions. It also demonstrates the utility of sequential analysis in making sense of the often complex interactions occurring in wild insect populations. [ABSTRACT FROM AUTHOR]

This paper reports a field case of the excavation of a large-scale basement parallel to twin existing shield-driven tunnels in soft soils. A comprehensive field monitoring program was conducted to measure the performances of the shield tunnels during excavation. The trapezoid-shaped basement with an excavation area of 26,982 m2 was excavated at the side of twin existing shield tunnels using a bottom-up excavation sequence. The tunnel horizontal and vertical displacements, and the tunnel convergence, were extensively measured. Based on field observations, the existing shield tunnels developed horizontal movements toward the excavation side, and settlements in the shield tunnels were observed due to the stress relief of the excavation of the large basement. The tunnel rings within the excavation width generally experienced horizontal elongation as a result of the reduction in the lateral earth pressure because of excavation. During the excavation of the elevator shaft, soil flow occurred, which resulted in a sudden and continuous increase in the tunnel horizontal displacements, tunnel settlements, and tunnel convergences. The down track suffered more serious adverse impacts than the up track, with eight leakages and 61 cracks observed in the down track. The newly induced cracks mainly occurred in a range within the excavation width, and were generally consistent with the distributions of the tunnel horizontal displacement and tunnel convergence. The measured data for the normalized tunnel horizontal and vertical displacements mainly fell between δh/|δhm| = δv/|δvm| − 0.5 and δh/|δhm| = δv/|δvm| + 0.4, and it was difficult to establish a direct linear relationship between them. However, a fairly good relationship between the tunnel convergence and horizontal displacement can be observed, the measured data mainly falling along δc/|δcm| = δh/|δhm|. An approximately linear relationship can be roughly found between the normalized tunnel vertical displacement and the tunnel convergence. The data mainly fell between δc/|δcm| = δv/|δvm| + 0.2 and δc/|δcm| = δv/|δvm| − 0.3. [ABSTRACT FROM AUTHOR]

Although irrigation systems largely sustain global agricultural production, their efficiency is often alarmingly low. While irrigation water (blue water) is critical for the water-saving irrigation of rice with a high water demand, the process and efficiency of irrigation water utilization need clarification. In this study, we examined the three commonly used irrigation and drainage patterns (frequent shallow irrigation (FSI), wet and shallow irrigation (WSI), and rain-catching and controlled irrigation (RCI)) in rice fields. We developed a tracking method for irrigation water flow decomposition, which includes irrigation water evapotranspiration (IET), irrigation water drainage (IDR), irrigation water leakage (IPC), and irrigation water field residual (IRE). Using this method, we established an irrigation water efficiency evaluation index system and a comprehensive evaluation method. Our tracking method is relevant to describing the irrigation water performance under varying irrigation and drainage patterns. The results revealed that the average irrigation water input for the three irrigation and drainage patterns between 2015 and 2018 was roughly 312.5 mm, wherein IET accounted for 148 mm. However, more than 50% of the irrigation water outflow, comprising IDR, IPC, and IRE, exceeded the total amount of irrigation water input. The mean values of the gross irrigation efficiency (GIE), net irrigation efficiency (NIE), and effective consumption ratio (ECR) for all treatments in the three-year period were 0.63, 0.47, and 0.75, respectively. Additionally, the irrigation water use efficiency was significantly higher in dry years compared to wet years. The fuzzy composite rating values of the three irrigation and drainage models from 2015 to 2018 were RCI, WSI, and FSI, in descending order, under varying precipitation conditions. The RCI patterns maintained a high composite rating value (greater than 3.0) under different precipitation conditions. Previous efficiency calculations disregarded the blue–green water migration process and did not differentiate the blue–green water flow direction in agricultural fields, creating significant biases in the outcomes. This study's method offers a new approach to evaluate the use of blue water resources in farmland. [ABSTRACT FROM AUTHOR]

Precision farming, a labor-saving and highly productive form of management, is gaining popularity as the number of farmers declines in comparison to the increasing global food demand. However, it requires more efficient crop phenology observation and growth monitoring. One measure is the leaf area index (LAI), which is essential for estimating biomass and yield, but its validation requires destructive field measurements. Thus, using ground and UAV observation data, this study developed a method for indirect LAI estimation based on relative light intensity under a rice canopy. Daily relative light intensity was observed under the canopy at several points in paddy fields, and a weekly plant survey was conducted to measure the plant length, above-ground biomass, and LAI. Furthermore, images from ground-based and UAV-based cameras were acquired to generate NDVI and the canopy height (CH), respectively. Using the canopy photosynthetic model derived from the Beer–Lambert law, the daily biomass was estimated by applying the weekly estimated LAI using CH and the observed light intensity data as input. The results demonstrate the possibility of quantitatively estimating the daily growth biomass of rice plants, including spatial variation. The near-real-time estimation method for rice biomass by integrating observation data at fields with numerical models can be applied to the management of major crops. [ABSTRACT FROM AUTHOR]

The move towards reducing environmental and health risks related to pesticide application in smallholder agriculture requires a more detailed understanding of farmers' awareness and pesticide use practices. Drawing on field observations and interviews with 90 randomly selected farmers, this study assesses the choice of pesticide, use patterns and the level of awareness of pesticide risks among male and female farmers growing vegetables on Idjwi Island, eastern Democratic Republic of Congo. The main crops grown are tomatoes, eggplants, and cabbages, which are vulnerable to pest attacks, leading to fruit rot (70%), leaf holes, and spots (17%), resulting in significant economic losses. To protect crops, farmers use various pesticides, including fungicides (e.g., Metalaxyl, Mancozeb) and insecticides (e.g., profenofos, Cypermethrin), based on their availability on local market, perceived effectiveness, and relatively affordable prices. Although the results did not reveal significant differences in pesticide use patterns between male and female farmers, men (41%) make decisions about pesticide purchase and use within households either alone or jointly with their spouses (31%). Regrettably, farmers disregard safety instructions and hygiene practices following pesticide application, leading to concerns about public health and the environmental impact of using these products. While we highlight the factors influencing farmers' willingness to wear protective equipment, findings also show that 75% of the participants are willing to pay $US 5 for any alternative method to pesticide use. This study emphasizes the need for improving awareness and recommends field farmers' schools to train farmers on pesticides' proper usage and management. The results suggest further research on farmers' exposure to pesticide and the exploration of existing alternative methods based on integrated pest management to advance sustainable agriculture. Plain Language Summary: Pesticide Choice and Use Practices Among smallholder farmers on Idjwi Island, Democratic Republic of Congo Pesticide-based crop protection has become prevalent among farmers seeking to increase crop yields and minimize losses in market-oriented vegetable farms. While the risk of pesticides for human health and the environment are still minimized and poorly understood by farmers, the choice of pesticides is essentially based on their availability on markets, perceived effectiveness, and affordable prices. In 41% of cases, men generally decide on the purchase and pesticide application. Regrettably, farmers disregard safety instructions and hygiene practices following pesticide application, leading to concerns about public health and the environmental impact of using these products. The results of this study can inform recommendations for the safety of agricultural workers, farmers and the protection of the environment. [ABSTRACT FROM AUTHOR]

Albinism is a genetic condition expressed as a lack of integumentary and retinal melanin. Although documented across many vertebrate species, albinism and other skin disorders are rarely observed in elasmobranchs (sharks and rays). The present study describes the first confirmed case of albinism in American cownose ray (Rhinoptera bonasus), and three other juveniles of the species with undetermined skin disorders observed in São Paulo, southeastern Brazil. Pigmentation disorders have already been observed in American cownose rays from the North Atlantic, including two cases of leucism and a possible albinism. Based on the results, it was discussed the possible consequences of albinism for the ray survival as well as the possible causes for the undetermined skin disorders. [ABSTRACT FROM AUTHOR]

Real-time monitoring and forecasting are essential to ensure an on-time and on-demand supply of water diversion projects. However, water transfer systems currently lack spatiotemporal data in a dense resolution, failing to monitor real-time conditions and test plausible scenarios. To address the problem, this paper proposes a novel digital twin framework. It includes a real-time self-correcting model, which combines (1) a hydraulic solver using the one-dimensional Saint-Venant equations; and (2) a method updating hydraulic states driven by field observed data. This framework consists of four phases: preparation, warming up, tuning, and monitoring and predicting. Particularly in monitoring and predicting, an identification method for diagnosing abnormal events is also proposed as one of the functions of the twin model. The model shows beyond 98% similarity to reality based on the metric similarity (S) proposed in this paper on both of two real-world scenarios: a large flow scenario and a normal one. The deviation is generally lower than 5 cm for water level 2 m3/s for discharge. The abnormal situation diagnosis method also provides timely fault detection for daily scheduling. It is anticipated that this framework can be a powerful tool to estimate current canal states and predict change trends, further ensuring the security and efficiency of operations for large-scale water diversion projects. [ABSTRACT FROM AUTHOR]

The small-clawed otter (Aonyx cinereus) is classified as vulnerable on the IUCN Red List and has recently been upgraded to Appendix I on CITES due to significant population reduction and commercial trade. Despite increasing conservation efforts for otters worldwide, land conversion, waste, pesticides, and poaching pose significant threats to otter populations. Previous studies have identified the presence and habitat characteristics of Aonyx cinereus in various regions of Indonesia. However, more research still needs to be done on the Ciliwung River species. The field observation was carried out from August to October 2022; with most fieldwork happening in the rainy season, there are better times to sample otter markings. Spraints and latrine sites were the most commonly reported signs of otter presence. Two direct sightings of otters were made during the survey, one of a group of eight otters at Ciliwung Bridge and another of two otters searching for food along the riverbank at Blue Bridge. We confirmed the presence of otters in this area through visual encounters, sign surveys, and direct sightings. The proximity of Aonyx cinereus to settlements in the Jabodetabek region makes this species vulnerable to hunting. It is essential to preserve the Ciliwung River so that it may be passed on to future generations. [ABSTRACT FROM AUTHOR]

Northeast and East China account for ~36% of the Chinese rice cultivation area, yet considerable spatial disparities in nitrogen use efficiency (NUE) exist between these regions. The underlying causes remain poorly understood. Herein, we conducted a case study in two sample sites from two regions, Wuchang and Changshu, using multi‐scale evidence chains spanning macro‐ and micro‐ processes to identify the determinants of spatial NUE variability. Field studies showed higher NUE (partial factor productivity, PFP, and agronomic efficiency, AE) but lower ammonia volatilisation in Wuchang paddy soil. By separating edaphic factors from climatic conditions, soil replacement pot studies between Wuchang and Changshu revealed that both apparent (AE and recovery efficiency, RE) and 15N‐traced NUE were higher, whereas 15N fertilizer losses were lower in Wuchang‐soil than Changshu‐soil irrespective of site, suggesting soil type contributed to differences in soil N retention capacity and NUE of the soils. Process‐scale results showed that greater rates of gross N mineralizsation (13‐fold higher), gross nitrification (93% higher), and denitrification (52% higher) in Changshu‐soil compared to Wuchang‐soil corresponded to functional gene relative abundance, signifying larger reactive N losses and reduced soil N retention capacity. Microbial community analysis suggested that the differential N transformations were caused by differences in ammonia‐oxidizing archaea (AOA) family nitrososphaeraceae and Nitrospira‐like nitrite‐oxidizing bacteria (NOB). This highlights the importance of specific efficiency‐enhanced strategies tailored to the edaphic characteristics of cropping regions, such as increasing soil N retention capacity using enhanced‐efficiency fertilizer in East China, while implementing conservation management strategies in Northeast China. Highlights: Field‐scale studies revealed higher NUE and lower NH3 volatilisation in Wuchang site.Soil replacement pot studies showed higher NUE in Wuchang‐soil regardless of sites.Process‐scale results unravelled high N losses and low soil N retention in Changshu‐soil.Varying NUE partially correlated with Nitrososphaeraceae AOA and Nitrospira‐like NOB. [ABSTRACT FROM AUTHOR]

We have developed the SNOVAL computational code to numerically simulate snow accretion on the conductor wire of a transmission line. Here, we present the theoretical aspects of SNOVAL version 2 such as the derivations of the model equations based on the physical process of snow accretion and conductor wire torsion, and the derivations of the mathematical form of the spatial and temporal discretization of the model equations. The validity of SNOVAL is examined using observational data obtained using a sector model apparatus designed to mimic snow accretion and wire rotation at the center of an actual transmission line. Field observations indicate that the SNOVAL snow accretion model is appropriate, although the SNOVAL results depend strongly on certain computational conditions such as the sticking efficiency, the accreted snow density, and an assumed mass-weighted terminal fall speed of wet snowflakes. Finally, the applicability of SNOVAL to snow accretion on a transmission line is demonstrated via numerical simulation of the dynamic behavior of wire rotation such as the snap-through phenomenon of a conductor wire equipped with counterweights. • SNOVAL was developed to numerically simulate snow accretion on a conductor. • Snow accretion model was validated using field observations of a sector model. • SNOVAL can simulate snap-through rotation of a conductor wire with counterweights. • Counterweights are effective in suppressing snow accretion and wire rotation. [ABSTRACT FROM AUTHOR]

Aim/Purpose The purpose of this study is to explore the correlation between contract cheating and online education in China, which has become a major concern due to the extensive promotion of online education worldwide amid the COVID-19 pandemic. Background Contract cheating, also known as academic ghostwriting, refers to the act of students outsourcing academic assignments to third parties, who complete the work on their behalf. With the development of online education, the incidence of contract cheating is rising progressively. Whilst numerous scholars have conducted extensive research on the causes, prevention, and handling of contract cheating, the issue persists and needs further localized understanding. Methodology This study employs a mixed-methods approach. First, textual data on Sina Weibo, a popular Chinese social media platform, is collected and analyzed using VOSviewer and NVivo12 software. Field observation methods are also utilized for theme analysis and sentiment analysis. Second, the theoretical framework of organizational theory is applied to explain the impact of different modes of online education implementation on contract cheating. Finally, based on the findings, possible solutions to mitigate contract cheating are proposed. Contribution This study contributes to the literature by providing a theoretical framework to explain the relationship between online education and contract cheating in China. The study's findings highlight the importance of the mode of online education implementation when addressing contract cheating. Findings This study finds that online education does exacerbate contract cheating in China, and the extent of this phenomenon varies depending on the mode of online education implementation. This study also identifies the lack of academic integrity education and supervision as a major factor contributing to contract cheating. Recommendations for Practitioners Reducing the costs of educational organizations in combating cheating through institutional arrangements, such as establishing effective channels of communication between teachers and schools and controlling teachers' workload outside of their primary responsibilities, can help curb contract cheating. Recommendations for Researchers Both history and reality have demonstrated that possible solutions cannot rely solely on new technologies or single institutional arrangements. Contract cheating is essentially an unethical means of competing for scarce resources, and as long as resources remain scarce, this phenomenon will persist. Impact on Society As a social phenomenon, contract cheating cannot be completely eradicated through top-down policy enforcement. Future Research The stringent enforcement against contract cheating also involves the education regulatory and judicial departments, and their relationship is worthy of future research. [ABSTRACT FROM AUTHOR]

With the increasing number of tourists in recent years, ensuring the safety of visitors in tourist attractions has become an enormous challenge for safety management. At present, many experiments have been conducted to study pedestrian dynamics, but empirical data on tourists' movement state under different weather conditions are still few. Therefore, a series of field experiments were conducted to analyze the effect of external weather and temperature on pedestrians' movement characteristics. The results show that pedestrians are more concentrated in the middle and inner tracks during the turning process to seek the shortest path on rainy days. Moreover, it is found that pedestrians speed up under the conditions with low (below 10 °C) and high (over 30 °C) temperatures. The average speed of pedestrians is 0.677 m/s as the temperature is below 0 °C, which is much higher than the average speed of pedestrians in other temperature ranges. In addition, the speed of pedestrians changed more dramatically under the low-temperature conditions. It is hoped that this research can provide a reference for crowd control and rational design of pedestrian facilities. [ABSTRACT FROM AUTHOR]

Previous studies have proven that rainfall-runoff characteristics in headwater catchments are affected by many factors, including topography, geology, and vegetation. However, only a few studies have explained the geological effects on rainfall-runoff characteristics based on observations from various catchments. In this study, we conducted runoff observations in 19 headwater catchments in two forests with different geological characteristics; based on these observations, we further conducted direct runoff and hydrograph recessions analyses. The runoff characteristics of the catchments were significantly affected by their local geological settings. Some catchments did not follow average trends, especially catchments with large baseflows, because of the effects of geological structures, such as dips and strikes in sedimentary-rocks and joints in granite. These catchments were likely to have wetter riparian zones, thereby facilitating direct flow, even in the case of reduced rainfall. [ABSTRACT FROM AUTHOR]

We report observations of alien dandelion (Taraxacum officinale group) consumption in an opportunistic predatory seabird, the brown skua (Stercorarius antarcticus lonnbergi), from a natural population on île Verte within the Kerguelen archipelago. Observations on a nearby island suggest that this behaviour is not specific to our study area, paving the way to future studies investigating whether this consumer innovation prevails in skua populations and results in dietary benefits. [ABSTRACT FROM AUTHOR]

• Operating shield tunnels affected by both the nearby and overlying excavation simultaneously in sensitive soft soils were investigated and presented. • The mechanism of improving the safety and serviceability of existing tunnels through tunnel reinforcement was revealed. • The impact of tunnel reinforcement on the adjacent existing tunnel during the construction stage was discussed. • Empirical methods estimating the impact range of side excavation, overlying excavation, and reinforcement construction were proposed. Adjacent engineering activities affect existing tunnels in service, causing safety concerns. Many studies have focused on single excavations overlying or parallel to adjacent existing tunnels. However, few have considered the responses of tunnels to multiple excavations with different orientations. In this study, the existing shield tunnels of Hangzhou Metro Lines 1, which were affected by both the nearby and overlying excavation simultaneously, in sensitive soft soils were investigated and presented. Field monitoring showed considerable displacement in the tunnels at different excavation stages. The interaction mechanism between the nearby and overlying excavation, the surrounding soil, and the existing tunnels was investigated by assessing the evolutionary pattern of the tunnel deformation. In addition, the mechanism of improving the safety and serviceability of tunnels through tunnel reinforcement, which has been ignored in past research, and the impact of tunnel reinforcement on the tunnel during the construction phase were evaluated. Empirical methods were proposed to estimate the impact range of nearby and overlying excavation and tunnel reinforcement construction. The results provide guidance for protecting metro tunnels during adjacent excavations in soft soils. [ABSTRACT FROM AUTHOR]

This study investigates multiscale variability of summer‐time precipitation around the northwestern coast of Luzon Island, the Philippines, by analyzing in situ observation data of a field campaign in summer 2018 conducted under the Years of the Maritime Continent‐Boreal Summer Monsoon study in 2018 (YMC‐BSM 2018) project. It is found that boreal summer intraseasonal oscillation modulates activity of precipitation diurnal cycle, with active diurnal cycle observed only under easterly (offshore) wind conditions in the free troposphere. On the other hand, in the period of westerly winds, quasi‐biweekly fluctuation is observed, with two heavy precipitation events. These events are associated with further intensified westerly winds caused by westward‐propagating quasi‐biweekly oscillations. Day‐to‐day precipitation variability over land during the two events is associated with the strength of monsoon winds blowing toward the mountain range, which is modulated cooperatively by the quasi‐biweekly oscillations and tropical depressions over the South China Sea. Plain Language Summary: In the Asian monsoon domain, including the Philippine Archipelago, Indochina Peninsula, and Indian Subcontinent, summer‐time monsoon circulation causes large amount of precipitation. Its temporal variation is caused by various large‐scale atmospheric phenomena, such as insolation diurnal cycle, tropical depressions, tropical cyclones, westward‐propagating cyclonic disturbances with quasi‐biweekly (10–20‐day) time scales, and so‐called boreal summer intraseasonal oscillations (BSISOs) that have 30–60‐day time scales and are characterized by northward‐propagating zonal wind anomalies. To deepen our understanding of the precipitation variability around the northwestern coast of Luzon Island, the Philippines, we conducted an intensive observation campaign in summer 2018. Analyses of weather radar, upper‐air sounding, and automatic weather station data reveal that BSISO considerably modulated diurnal cycle. The active diurnal cycle characterized by afternoon land precipitation and subsequent offshore migration of precipitation areas was observed only during the period of easterly winds in the free troposphere associated with BSISO. We also present an example of the cooperative influence of quasi‐biweekly oscillations and tropical depressions over the South China Sea. They modified the strength of monsoon winds blowing toward the mountain range and caused day‐to‐day precipitation variability over land during two heavy precipitation events that occurred in the period of westerly winds associated with BSISO. Key Points: The observation campaign in northwestern Luzon Island in summer 2018 captured precipitation variability involving multiscale interactionThe diurnal cycle with evening offshore migration of precipitation areas occurred only under the condition of offshore windsQuasi‐biweekly oscillation and tropical depressions cooperatively modified monsoon winds, contributing to variation of land precipitation [ABSTRACT FROM AUTHOR]

Spined loaches, Cobitis spp., have been studied in broad fields of research. Particularly, this taxon has attracted attention because of sexual interactions, such as reproductive interference and hybrid speciation, among species. Nevertheless, knowledge of the reproductive behaviors of this genus has been limited to findings from visual observations of aquarium-resident individuals. For this study, we shot videos and analyzed reproductive behaviors of Cobitis magnostriata in the field. We also investigated cues used by males to track females. Based on our observations conducted at a ditch near the shore of Lake Biwa during May–June, 2020, the sequence of courtship and spawning behaviors was divided into four phases: phase 1, a male tracks a female; phase 2, the male swims parallel to a female; phase 3, the male wraps the posterior part of the female's body from her dorsal fin and remains motionless; phase 4, after the male wraps the female tighter, the female vibrates to spawn. Additionally, we demonstrated that water vibrations initiate the male tracking behavior (phase 1). The adoption of such a non-species-specific cue might be one reason for which the sexual interspecific interactions have been widely reported in this genus. [ABSTRACT FROM AUTHOR]

The particulate matter (PM) pollution has been significantly improved by carrying out various valid emission control strategies since 2013 in China. Meanwhile the variation trend of nitrous acid (HONO) is worthy to investigate due to its vital role in the atmospheric oxidation process. In this study, field observation in the winter is conducted to investigate the concentration of HONO in an urban area of Beijing. In the winter of 2019, the mean HONO concentration is 1.38 ppbV during the whole winter. Photo-enhanced NO 2 heterogeneous reactions on the ground and aerosol surfaces were found as the possible daytime sources of HONO. Compared to O 3 , photolysis of HONO dominates the primary OH sources during the winter time. To understand the HONO pollution patterns by years variation, multi-year data is summarized and finds that primary pollutants including CO and NO decreased, but secondary pollutants i.e., HONO (mostly generated via secondary process) increased. Our study highlights the requirement to mitigate secondary pollution by control HONO concentration. [Display omitted] [ABSTRACT FROM AUTHOR]

As a representative species of intermediate volatile organic compounds (IVOCs), long-chain alkanes are considered to be important precursors of secondary organic aerosols (SOA) in the atmosphere. This work reviews the previous studies on long-chain alkanes in the atmosphere: (1) the detection methods and filed observations of long-chain alkanes in both gas and particle phases are summarized briefly; (2) the laboratory studies of long chain alkanes are reviewed, the kinetic data, reaction mechanism, SOA yields, and physicochemical properties of SOA are included in detail; (3) the research progress related to model simulations of long-chain alkanes are also discussed. In addition, based on available research results, several perspective contents are proposed that can be used as a guideline for future research plans. [Display omitted] [ABSTRACT FROM AUTHOR]

We investigate the characteristics of a dust-devil-like vortex (DDLV) observed using thermal image velocimetry (TIV) at a sports ground in Tokyo. Thermal image velocimetry provides unique observations of the two-dimensional velocity distribution for a DDLV with high spatio–temporal resolution (i.e., tens of cm s−1) near the ground. Two DDLVs were detected, one each in summer and winter, and the quantitative features of the larger, stronger DDLV in the winter are examined. The size and strength of the detected DDLV, which are quantified using TIV, are within the ranges reported in past observations and numerical simulations of dust devils. The vortex appears at the boundary of a cold-air current near a 55-m building wall, and persists for more than 3 min. [ABSTRACT FROM AUTHOR]

Hypomelanosis refers to a suite of skin pigment abnormalities, including albinism, leucism and piebaldism. While documented across many vertebrate species, examples of hypomelanosis are rarely seen in chondrichthyans, with little insight into the potential effects on survival. Here, we report the first observation of abnormal skin pigmentation indicative of piebaldism in the Atlantic nurse shark Ginglymostoma cirratum, representing only the second reported case of skin aberrations for this species. This extremely rare observation is discussed in the broader context of fitness variation and long‐term survival. [ABSTRACT FROM AUTHOR]

A 25.5 km long access road has been constructed in a hilly area in Cisokan region. Several slope instabilities occurred during the rainy season, particularly at the end of heavy rainfall. A comprehensive study was performed to understand the characteristics of rainfall-induced slope instability. The study consisted of field observation, analyses of field and laboratory test data, and numerical analyses. The study revealed that in general there were two categories of slopes with instability characteristics: (i) slopes with a significant groundwater level increase during rainfall; (ii) slopes with an insignificant groundwater level increase during rainfall. In the first category, the slope instability was caused by a loss of matric suction and eventually the pore-water pressure, uw became positive as indicated by an increase of the groundwater level. In the second category, the slope instability was caused by a loss of matric suction without a rise in pore-water pressure, uw, to a positive magnitude. Two empirical curves of slope stability were developed as a preliminary guidance to assess slope stability during rainfall in the region. [ABSTRACT FROM AUTHOR]

This study analyzed the characteristics of infragravity (hereafter IG) waves under a microtidal and swell-dominated wave climate based on the field observations collected in the nearshore waters (water depth: ∼ 13 m) of southern Sri Lanka. The main focus is on the dependence of nearshore IG waves on the incident short wave parameters, with particular attention to the influence of the short wave spectral shape on the IG wave characteristics. The observation results indicate that IG waves are primarily locally excited by incident swell wave energy, and accurate prediction of the IG wave height can be achieved using the parameter H S 2 T m − 1 , 0 , which represents the short wave energy flux. Bound IG wave energy is much smaller than the free IG wave under conventional sea states but becomes significant under high-energy swell sea states. Higher levels of IG wave energy are found to be forced under narrower spectral shapes and smaller directional spreading short wave conditions, and these conditions typically correspond to stronger coupling strengths in the bound IG wave theory. Compared to the single-peaked spectra wave condition, the forced IG wave energy decreases under the double-peaked spectra wave condition. This is likely mainly because the latter tends to have a broader spectrum and a larger directional spreading. On the other hand, under the narrow-banded spectral short wave conditions, IG wave energy is inclined to be distributed over a lower and smaller frequency range. This is noteworthy because lower-frequency IG waves tend to be more difficult to break. In addition, the bound IG wave energy was found to increase at low tide, but for the intermediate water depths in which the observation site is located in this study, the influence of the small tidal range in the study area on the IG wave energy was not significant. [ABSTRACT FROM AUTHOR]

Gu, J.; Zhu, J., and Lyu, H., 2021. Observation and analysis of water and salt transports in the North Branch of the Changjiang Estuary. Journal of Coastal Research, 37(3), 518–527. Coconut Creek (Florida), ISSN 0749-0208. The North Branch (NB) is the first-order bifurcation of the Changjiang Estuary and is an extremely shallow water channel. The greatest characteristic of saltwater intrusion is the saltwater spillover from the NB into the South Branch (SB). A field observation was conducted in the NB from 21 to 27 February 2017 to understand the water current and salinity variation. The residual unit width water and salt fluxes, as well as their decomposed terms, were calculated to discuss the mechanisms of water and salt transport. The tidal and vertical variations in ebb and flood duration, current velocity, and salinity during the neap-middle-spring tide were presented and dynamically analyzed in detail. The direction of the Eulerian water and salt transports and tidal pumping salt transport varied by site, vertical layer, and tidal type, whereas the Stokes drift water and salt transports were landward. During neap tide, the total residual water and salt fluxes in the upper layer of the whole NB were seaward transported because of the runoff effect; the total water and salt fluxes in the lower layer were landward in the lower-middle and lower reaches of the NB, reflecting the existence of a two-layer estuarine circulation. During the moderate tide, the total residual water and salt fluxes were seaward in the whole NB except in the lower layer in the low reaches of the NB, which were landward due to the strong baroclinic effect. During the spring tide, all the total residual water and salt fluxes were landward because some flood water flowed into the SB, resulting in an imbalance between the flood and ebb water volumes in the NB. The dynamic processes of water and salt transport from the NB into the SB during spring tide were revealed by the observation and flux decomposition method. [ABSTRACT FROM AUTHOR]

Liquefaction of seabed sediments under the action of storm waves is an important form of seabed instability, which may cause damage to submarine structures such as pipelines and cables. A commonly used parameter to identify sediment liquefaction is pore pressure. The pressure response of the pore water at different depths of a silty soil seabed under storm waves was monitored by a probe rod in the Yellow River delta. The probe is made of a steel pipe with a length of 8 m and an outer diameter of 10 cm, which is equipped with 10 pore pressure sensors. According to the collected data, under a water depth of 8 m, silty soil seabed liquefaction starts when the significant wave height reaches 0.5 m, and the liquefaction depth is between 3.3 and 3.8 m under waves with a significant wave height of 3.65 m. Seabed liquefaction develops in a top-down manner, and the average development rate of the liquefaction depth is approximately 0.17 m/min. [ABSTRACT FROM AUTHOR]

All editions of the Highway Capacity Manual have dedicated chapters to analysis of weaving sections. These chapters are taken as the base of action in many regions of the world including Iran. Therefore, this study aims at evaluate and compare the precision and effectivity of models proposed in four recent editions of HCM. Results indicate that in terms of adaptation with observed values in Iranian highways, the third edition performs best in estimating the speed of non-weaving vehicles, edition six in estimating the rate of lane change, and edition five in estimating the rest of variables and the level of service. Consequently, a combined model is suggested which presents more satisfactory results than the evaluated models. In detailed analysis of the evaluated models, it is determined that simultaneous increase of volume ratio and total demand would increase the discrepancies of the output of these models' actual values. [ABSTRACT FROM AUTHOR]

Longshore and cross-shore currents in the surf zone were observed on a dissipative barred beach for 20 days using a horizontally mounted acoustic-Doppler current profiler (H-ADCP). This novel deployment strategy allowed for the synoptic measurement of the longshore current at approximately mid-depth at several cross-shore locations. The longshore current data were analyzed with wave and tide level data to show the effect of tidal range on the variation of the longshore current with respect to cross-shore location. The longshore current was higher near the outer bar area than that observed near the inner bar. Moreover, the current became higher during the low tide and lower during the high tide. A longshore current model was proposed using the spring and neap tide data sets and then applied to the remaining observation period during large events of incident wave energy flux. The model with the relative water level luded provided sufficient accuracy to account for the tide effects. [ABSTRACT FROM AUTHOR]

• FBG-based fiber F-P interferometer strainmeter arrays for field observation. • Large-scale, real-time multiplexed strainmeter array features ultrahigh-resolution. • The array in Lijiang has 4.80-pε/√Hz @ 30 Hz resolution with 0.22-m cavity length. • The array in Heqing has 476-fε/√Hz @ 30 Hz resolution with 1.4-m cavity length. • The arrays have successfully recorded daily earth tides and over 100 earthquakes. Mining mass data of the earth's surface deformation is a promising approach for earthquake early-warning, raising an urgent demand for developing large-scale optical fiber strainmeters. This paper presents the implementation and results of large-scale, ultrahigh-resolution, real-time multiplexed fiber Bragg grating-based Fabry-Perot interferometer (FBG-FFPI) strainmeter arrays for field observation. The Pound-Drever-Hall technique locks master and slave single-sideband lasers onto the FBG-FFPI resonance peaks for precise strain measurement. A 10-channel array was successfully utilized for field observation at Lijiang National Seismic Station, which accurately recorded over 100 earthquakes and the earth's daily tide signal. The FBG-FFPIs have a strain resolution of 4.80 pε/√Hz @ 30 Hz with a 0.22-m cavity length. A 4-channel array with a longer cavity length of 1.4 m was also established at Heqing Seismic Station, showing advantageous performances. These results demonstrate the significant potential of FBG-FFPI strainmeter arrays in providing geophysical data for earthquake early-warning and hazard mitigation. [ABSTRACT FROM AUTHOR]

Roadways adjacent to a mining face are crucial for ensuring safe production, transportation, and the security of personnel. Nevertheless, the anchoring mechanisms and the integrity of the surrounding rock structures of these roadways have frequently been underestimated in mining endeavors. This study, using Xin'an Coal Mine in Gansu as an example, conducted an in-situ analysis of four anchoring methods to examine the axial force fluctuation characteristics and mechanisms of cable anchorage during coal mining. It was found that the lagged prestressed full-length anchorage demonstrated the most effective control. Subsequently, the study revealed the periodic subsidence phenomenon of roadway roofs on both sides of the working face, which is closely associated with periodic weighting. Based on monitoring results, the roadway roof was divided into three zones—'Peak Zone,' 'Valley Zone,' and 'Transition Zone'—using the periodic weighting intervals as units. Finally, the study employed a time-space detection method to observe the development pattern of roadway roof cracks and delamination during the coal mining cycle. The validation results indicated a low accuracy rate for this method. Additionally, the study discussed the applicable conditions for lagged prestressed full-length anchorage, measures to address roof subsidence in the 'Peak Zone,' and considerations for improving the time-space detection method. The research findings offer new insights into the impact of neighboring engineering disturbances on underground space engineering. • Field study of axial characteristics of four anchoring forms for cable bolts. • Revealing the phenomena and causes of roof deformation fluctuations in roadways. • Observing rock mass damage patterns using the time-space detection method. [ABSTRACT FROM AUTHOR]

Whittleia retiella (Newman, 1847) is a threatened salt marsh species of the bagworm moth family Psychidae. For its preservation it is necessary to develop efficient tools to survey its distribution and habitat requirements in order to use appropriate conservation methods. Such tools may be pheromone-based monitoring systems, which have documented efficacy in establishing the occurrence of cryptic insect species in nature. By using gas chromatography combined with electroantennographic detection (GC-EAD), we found two compounds in female W. retiella headspace samples and whole-body extracts that elicited electrophysiological activity in male antennae. Gas chromatograpy coupled with mass spectrometry (GC-MS) operating in electron impact (EI) mode and comparison of the analytical data with those of synthetic reference compounds showed the chemical structures of these putative pheromone components to be (1S)-1-methylpropyl (5Z)-dec-5-enoate and 1-methylethyl (5Z)-dec-5-enoate. Field assays using baits loaded with synthetic compounds revealed that conspecific males were attracted to (1S)-1-methylpropyl (5Z)-dec-5-enoate alone or in combination with 1-methylethyl (5Z)-dec-5-enoate, whereas 1-methylethyl (5Z)-dec-5-enoate neither attracted nor repelled males in the field assays when tested alone. This study shows the potential of using (1S)-1-methylpropyl (5Z)-dec-5-enoate for monitoring W. retiella to gather more detailed information about the geographic distribution and habitat needs of this rare moth. [ABSTRACT FROM AUTHOR]

The common black field cricket, Gryllus assimilis (Orthoptera: Gryllidae), damages young plants of red cedar, Juniperus virginiana (Cupressaceae); strawberry, Fragaria × ananassa (Rosaceae); sugarcane, Saccharum officinarum (Poaceae); teak, Tectona grandis (Lamiaceae); upland cotton, Gossypium hirsutum (Malvaceae); and, mainly, Eucalyptus spp. (Myrtaceae). The objective of this study was to investigate the biological and behavioral parameters of this insect in the laboratory and in Eucalyptus spp. plantations in Inhambupe, Bahia State, Brazil. The incubation period and the viability of G. assimilis eggs were 11.87 days and approximately 22%, respectively. The duration of the nymphal stage was 62.34 days with approximately 60% of the nymphs obtained in the laboratory being females. The average number of egg batches per female, eggs per female, and eggs per batch per female of this insect were 25.50, 862.17, and 34.65, respectively. G. assimilis females lived for 76.50 days in the adult stage, and 138.34 days in total, from egg through nymph to adult. Males produced three characteristic sounds: one for the marking of territory, one for courtship, and one when alone. G. assimilis fed primarily on weeds but, in their absence, it damaged young Eucalyptus spp. plants. This paper presents important data on the biology and behavior of G. assimilis; this information may encourage additional biological research, laboratory rearing, and integrated management of this pest. [ABSTRACT FROM AUTHOR]

Field observations were conducted during relatively mild wave conditions at a dissipative barred sandy beach to investigate the cross-shore sediment dynamics from the inner surf zone to the offshore side of the outer bar. Fluorescent sand tracers of five different colors were placed on the seabed at different cross-shore locations, and sand core samples were extracted respectively 11 and 20 days after the placement of tracers. Moreover, nine cross-shore bathymetric/topographic beach surveys were conducted, and the water level, wave, and wind conditions were observed. The objective of this research was to investigate the mechanisms of the on- and offshore-directed sediment transport during the inner- and outer-bar accretion events. The analyzed results revealed that at the inner surf zone, the sediment was dominantly transported in the onshore direction. The sediment was also transported offshore-ward due to the undertow; however, this occurred until the offshore end of the trough region. Overall, the outer bar shape affected the on-offshore sediment transport rate. The sediment movements in the onshore region and offshore region of the outer bar were not related; however, the outer bar was formed with the sediments from both the inner- and outer-bar regions. [ABSTRACT FROM AUTHOR]

Water-soluble inorganic ions (WSI), a major component of PM 2.5 , often increased rapidly during the haze event in Beijing. Sulfate (SO 4 2−), Nitrate (NO 3 −), and Ammonium (NH 4 +) are three main components of WSI. Since year 2015, sulfate concentrations in PM 2.5 has gradually decreased owing to the effective control of SO 2 emissions. However, the contribution of nitrate to PM 2.5 has significantly increased during haze events in Beijing at the same time. In this study, a highly time-resolved online analyzer (Monitor for Aerosols and Gases, MARGA) was employed to measure the WSI in PM 2.5 in Beijing from 5 February to 15 November 2017. Three typical haze events during this sampling period were investigated. During heavy pollution episodes in winter, nitrate concentrations increased from 7.5 μg/m3 to 45.6 μg/m3 (45.0% of WSI), while sulfate increased from 4.2 μg/m3 to 20.1 μg/m3 (19.8% of WSI). This indicated that nitrate is more important than sulfate as a driver for the growth of PM 2.5 during the period of heavy air pollution in winter. Nitrate also dominates the increase of WSI in the pollution episodes in autumn, with an average concentration of 52.5 μg/m3, and contributed up to 67% of WSI. The average concentration ratio of NH 4 + to SO 4 2− was higher in autumn (1.02) than that in summer (0.74) and close to that in winter (1.00). This is mainly because the emission control of coal combustion in Beijing and surrounding areas results in an NH 3 -rich and SO 2 -lean atmosphere, which promoted the formation of ammonium nitrate. Our study indicates that nitrate has become the most important component of WSI in PM 2.5 and is driving the rapid growth of PM 2.5 concentrations during heavy pollution episodes in Beijing. Therefore, more efforts shall be made to reduce the nitrogen oxide and ammonia emissions in Beijing and surrounding areas. Unlabelled Image • Nitrate become the main component of PM 2.5 than sulfate during the haze events in Beijing. • High NOx emission, low temperature and low aerosol acidity are the key factors to promote nitrate formation in Beijing. • Molar ratio of NH 4 + to SO 4 2- increased from 1.5 (before 2013) to 3.33 (2017) due to ammonia-rich atmosphere in Beijing. [ABSTRACT FROM AUTHOR]

• We analyze pedestrian route choice behavior around obstacles in a simple scenario. • We compare a field study and a virtual experiment with identical setups. • We find qualitatively similar results in both settings. • This helps to validate virtual experiments as a useful methodology. Pedestrians often need to decide between different routes they can use to reach their intended destinations, both during emergencies and in their daily lives. This route-choice behavior is important in determining traffic management, evacuation efficiency and building design. Here, we use field observations and a virtual experiment to study the route choice behavior of pedestrians around obstacles delimiting exit routes and examine the influence of three factors, namely the local distance to route starting points and the pedestrian density and walking speeds along routes. Crucially, both field study and virtual experiment consider the same scenario which allows us to directly assess the validity of testing pedestrian behavior in virtual environments. We find that in both data sets the proportion of people who choose a closer exit route increases as the difference in distance between exit route starting points increases. Pedestrians' choices in our data also depend on pedestrian density along routes, with people preferring less used routes. Our results thus confirm previously established route choice mechanisms and we can predict over 74% of choices based on these factors. The qualitative agreement in results between the field study and the virtual experiment suggests that in simple route-choice scenarios, such as the one we investigate here, virtual experiments can be a valid experimental technique for studying pedestrian behavior. We therefore provide much-needed empirical support for the emerging paradigm of experiments in virtual environments. [ABSTRACT FROM AUTHOR]

• Weld-induced rail squats are studied through a five-year continual field monitoring and numerical simulations. • Different stages in the development of squats were observed in the field monitoring. • The development process is presented, from inhomogeneous material in HAZs to two-lung-shaped squats associated with cracks. • The formation mechanism in terms of dynamic contact force and differential plastic deformation is proposed. • Numerical simulations are performed to verify the pre-cracking process. Weld-induced squats are a major damage type in high-speed railways as well as in conventional railways. They incur high maintenance costs and endanger operational safety. This paper first presents and analyzes five-year continual field monitoring observations and measurements of squats at rail welds. A hypothesis of the formation and development process of the squats is proposed, which includes three steps. Steps 1 and 2 are pre-cracking, and Step 3 is post-cracking. To verify the pre-cracking process, a three-dimensional (3D) finite element (FE) model is then built up to simulate the vehicle-track interaction with detailed consideration of the local wheel-rail frictional rolling contact. Not only dynamic contact forces but also plastic deformation and wear are calculated. Starting from a smooth rail surface with varying yield stress derived from field-measured hardness, the numerical analysis confirms the hypothesis that the varying hardness at heat-affected zones (HAZs) leads to initial V-shaped irregularities due to differential plastic deformation. Afterward, the surface irregularities excite the dynamic longitudinal contact force, which in turn produces a W-shaped surface pattern through further differential plastic deformation. The growth of the W-shaped pattern leads to the formation of squats. This work provides insight into the squat formation process at rail welds and suggests that welding quality control in terms of hardness variation in the HAZs could reduce or even avoid squats. Early detection of squats with dynamics-based methods is possible. [ABSTRACT FROM AUTHOR]

Wide longitudinal ridge tillage has significant effects for increasing crop yield. Field observation shows that in the black soil region of Northeast China, wide longitudinal ridge tillage has been widely promoted in the intensive farms on which large agricultural machines are used. However, hillslope soil erosion of wide longitudinal ridge tillage is seldom studied. Therefore, in typical black soil region, in this study, two large natural runoff plots with gentle slope gradient were established in Liangshigou watershed in Keshan County, Heilongjiang Province. One was wide longitudinal ridge tillage with 320 m slope length and 3-m slope width and another was narrow longitudinal ridge tillage with 320 m slope length and 2 m slope width. Ridges were established on a field of silty clay loam (USDA classification). The slope gradients ranged from 2°-7°. According to literature review and field measurements of the wide and narrow ridges in black soil region of Northeast China, the used wide ridges were 15-cm high, 110-cm wide; the used narrow ridges were 15- cm high, 65 cm wide. A laboratory simulated rainfall experiment was conducted in the simulated rainfall hall of the State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Yangling City, China. The soil used in the laboratory simulated rainfall experiment was collected in the natural runoff plot. According to the standard of erosive rainfall in Northeast black soil region of China, the simulated rainfall intensities were 50, 75 and 100 mm/h. Each rainfall experiment lasted 60 min. The wide and narrow ridges used in the simulated experiments were consistent with the large natural runoff plot in Keshan County. Based on the runoff plot observation and laboratory simulated rainfall experiments, the differences of hillslope soil erosion between wide and narrow longitudinal ridge tillage in black soil region of China were analyzed. The results showed that under both field runoff observation and laboratory simulation, hillslope soil losses from the wide longitudinal ridge tillage hillslope were 64.4% - 90.4% and 33.2% - 57.9% lower than that from the narrow longitudinal ridge tillage. Field observation indicated that there were significant or strong significant positive correlations among the soil loss, runoff and PI30. The increment of soil loss with runoff and PI30 in narrow ridge-tillage system was larger (P< 0.05) than that in wide ridge-tillage system. The relationship between soil loss and PI30 was power function, while the relationship between soil loss and runoff was linear function (R²＞0.99). Indoor simulated experiments showed that there were linear relationships between soil loss and runoff under two longitudinal ridge tillage systems (R²≥0.81). The increment of soil loss from the wide longitudinal ridge tillage system was lower (P< 0.05) than that from the narrow longitudinal ridge tillage system. Compared with the narrow longitudinal ridge tillage, the reduction of soil loss by wide longitudinal ridge tillage decreased with the increase of PI30; when PI30 was 433.9 - 605.1, the reduction of soil loss by the wide longitudinal ridge tillage was 74.8%-90.4% and when PI30 were 1520.6 and 1708.6, the reduction of soil loss by the wide longitudinal ridge tillage was 64.4%-66.5%. Both field observation and simulated experiments displayed that the wide longitudinal ridge tillage had better effects on controlling hillslope soil erosion, compared with the traditional narrow ridge tillage. Therefore, promotion of wide ridge tillage system might have great significance in protecting Mollisol resources in the black soil region of Northeast China. [ABSTRACT FROM AUTHOR]

Hydrodynamic and hydrographic data collected on the inner shelf of Fire Island, NY, over a region of shoreface-connected ridges (SFCRs), are used to describe wind-driven circulation over uneven topographies along relatively straight coastlines. The data reveal a predominantly alongshore flow, under westward wind forcing, with localized offshore current veering over the SFCR crests and an onshore veering over the adjacent troughs. Alongshore momentum balance analysis of the observations reveals that total acceleration (i.e., local and advective) and bottom stress are balanced by wind stress and pressure gradient. A numerical model is used to verify the experimentally derived results and to analyze the cross-shore momentum balance which is not resolved by the experimental data. Analysis of the numerical and field data reveal that the total alongshore pressure gradient force can be considered as the sum of a local and a regional component. The former is correlated with the alongshore advective acceleration that develops over the crest of the ridges resembling a Bernoulli-like pressure-flow relationship. The regional alongshore pressure gradient is related to wind stress with which it maintains a strong, negative relationship. Over the ridge crests the cross-shore veering of the flow is due to mass conservation, associated with a balance between cross-shore advective acceleration and local cross-shore pressure gradient. Under variable wind conditions the regional pressure gradients are more important, as compared to quasi steady-state conditions which increase the influence of the local scale pressure gradient. A time scale of 6 h is found as the temporal scale required for the local pressure gradients to make a significant contribution to the momentum balance. • The hydrodynamic driving force was best described as a combination of wind stress and pressure gradient force. The response of the flow was best described by bottom stress, local acceleration, and advective acceleration. • Current veering over shoreface-connected ridges is driven primarily by two processes: cross-shore variation of alongshore advective acceleration which correlates with a cross-shore pressure gradient and drives flow (described as a Bernoulli-like process), and, bottom frictional-torque. • Advective acceleration is exhibited through high current velocity over SFCR crest and low current velocity over SFCR trough. This distribution of current velocities causes: current divergence at SFCR crest and a local water level set-down, as well as a current convergence and water level set-up over troughs. The water level can thus be described as creating a local pressure gradient response to the distribution of advective acceleration, a process heron described as a Bernoulli-like process. • The total pressure gradient force can be considered as the sum of a local and a regional pressure gradient force. The former is correlated with the alongshore advective acceleration that develops over the crest of the ridges resembling a Bernoulli-like pressure-flow relationship. • Under variable wind conditions the regional pressure gradients are more important, as compare to quasi steady-state conditions which increase the influence of the local scale pressure gradient. [ABSTRACT FROM AUTHOR]

This paper reports the structural failures and collapse of heritage structures in Kathmandu Valley, Nepal, during the 2015 Nepal earthquake, and presents preliminary findings regarding the causes of failures and collapses. Field reconnaissance was carried out immediately after the main shock (Mw 7.8) on April 25 and the strongest aftershock (Mw 7.3) on May 12. It was observed that the performance of heritage structures was influenced by the combination of several factors, including structural and architecture type, configuration and structural deficiency, local site effects and ground-motion characteristics, age and maintenance level, material quality, etc. It was observed that dome structures performed very well, followed by pagoda (tiered temple), and shikhara structures were found as the most vulnerable structures. Moreover, it was observed that structures that had been seismically retrofitted and well maintained appeared to perform well. Some recommendations are made to improve the seismic performance of the heritage structures in Kathmandu Valley. [ABSTRACT FROM AUTHOR]

A modified typhoon numerical model is proposed based on data measured during the landfall of several typhoons as well as the fitting relationships of typical typhoon field parameters such as the maximum wind speed radius Rmali associated with storm scale field and radial pressure distribution coefficient βrelated to pressure field. The modified model considers the correlation among field parameters and is applicable for the region of Southeast coast of China. Using the field observation data of 57 typhoons from 1971 to 2015 in the Houjia Town meteorological station, Shanghai, the equivalent roughness length of engineering site was optimized as z0 = 0. 095 m. The validation of maximal wind speeds for each typhoon between the observed and simulated results was conducted. Combining the observation data of typhoon tracks and the fitting relationships of typical field parameters，the wind speeds observed by Houjia Town station of four typically stronger typhoons was reproduced by the improved typhoon engineering model. The relative errors of maximum wind speeds between the observations and the model are within 12%. It is demonstrated that the present model is sufficiently reliable for predicting the maximum typhoon winds. Basic wind speeds and profiles of the Houjia Town station and typical engineering sites in the Shanghai region were calculated via the Monte-Carlo stochastic simulation method and the peak over Threshold method. The 10 min mean wind speed at a height of 10 m with the return period of 100 years in the Houjia Town station and the category B exposure (20 = 0.05m) of Shanghai are 31. 51 m/s and 37. 46 m/s with the standard derivation of 2. 05 m/s and 2. 66 m/s, respectively. Moreover, the preferable mean wind profile models for engineering sites with four kinds of category under typhoon winds were suggested after comparing three different wind profile models. [ABSTRACT FROM AUTHOR]

Highlights • An equation for estimating the daily UHII max is evaluated with a dataset of 658 days. • Robust and satisfactory estimation of the UHII max under various weather conditions. • A method to apply the equation to building energy simulation is developed and validated. • Implying that the equation and the method have the potential to be applicable to other cities. Abstract The reliable estimation of the urban heat island intensity (UHII) within an urban canopy will benefit a number of fields of research such as urban design, public health, and building energy performance. A diagnostic equation for estimating the daily maximum UHII (UHII max), which is based on routine meteorological data and basic urban properties, was extensively tested with the long-term observations from the metropolis of Nanjing, China. The field measurement has been carried out based on the Local Climate Zone (LCZ) scheme, which is a standardized classification protocol for urban temperature studies. The temperature data set of 658 days collected from six different LCZ classes was used for testing. The results show that the diagnostic equation produced a robust and satisfactory estimation of the daily UHII max under various weather conditions. The overall performance of the equation for Nanjing, that has a root mean squared error (RMSE) of 0.95°C and a median absolute error (MEAE) of 0.60°C, closely approximates its performance for the 14 cities in northwestern Europe (RMSE = 0.91°C, MEAE = 0.58°C). The results also imply that the equation has the potential to be applicable to other cities. Another attempt in this study was to develop a method to apply the diagnostic equation to building energy simulations (BES). The hourly heat island intensities were derived from the estimated UHII max based on the typical diurnal pattern of UHII evolution. An apartment was modeled with the BES program EnergyPlus to examine the validity of the proposed method. Using the modeled and measured temperature data as the inputs in the EnergyPlus simulations, the annual, monthly, and hourly energy demands for cooling and heating were investigated and compared. For all the six LCZ sites except the large low-rise case (LCZ 8), the impacts of the heat island effects at the neighborhood scale on building energy performance were reasonably evaluated with the method. The limitations and perspectives of the equation and its application to BES have also been discussed. [ABSTRACT FROM AUTHOR]

Quantitative real-time observations of a tidal bore in a macro-tidal estuary are difficult and dangerous, particularly in large estuaries. Mathematical and numerical models have been used to predict tidal bore advances; however, to date, there have been no validations of large-scale flow patterns. A marine radar can provide valuable real-time information on tidal bore propagation. In this paper, a template matching method using a cross-correlation algorithm was explored to estimate the evolution and celerity of a tidal bore with medium resolution marine radar images. The Qiantang River tidal bore was recorded at two different geographical locations. Characteristic flow patterns were derived and analysed, including temporal changes over a relatively large-scale area. The experimental results showed that the radar-derived celerity and calculated height of the tidal bore were consistent with visual observations in this estuarine zone. Image 1 • Quantitative real-time observations of a tidal bore in a macro-tidal estuary. • Cross-correlation between successive radar images yield instantaneous bore celerity. • Both magnitude and direction of the bore celerity are derived. • Radar-derived results are validated by visual observations. [ABSTRACT FROM AUTHOR]

Abstract The process of blowing snow is important for secondary distribution of water resources in seasonal grassland snow areas because it affects the regeneration, growth, and nutrient circulation of vegetation. This study conducted field observations of blowing snow and snow accumulation in a grassland area typical of northern China. The results showed that in the near-surface area (0 to 100 cm), snow drifting intensity increased exponentially with a mean wind speed of 2 m/s, and that the maximum snow drifting intensity, which was found within 30 cm of the surface, accounted for 89.61% of the total amount of snow drifting within the near-surface area. The snow drifting intensity was strong under conditions of an abundant snow source and sparse vegetation, with an average value of 2.203 g/cm/min. The snow drifting intensity was lower under conditions of an insufficient snow source and higher vegetation coverage, with an average value of 0.545 g/cm/min. In typical grassland areas with a bare surface and sparse vegetation, snow cover is generally thin; the mean snow depth in such areas during the observation period of this study was 4.03 cm, and this constituted the source of the drifting snow. Snow cover was thicker in areas with taller grass and greater vegetation coverage; the mean value of snow depth in such areas during the observation period was 16.56 cm, and this constituted the main snow cover area. The observation results provide basic data to support the estimation of snow cover amount in grassland ecosystems, optimization of the utilization of snow water resources, regularization of snow cover, restoration of vegetation, and prevention and control of snowstorms. Highlights • The process of blowing snow and snow cover were observed. • The relationship between vegetation and snow cover were surveyed. • Snow areas with a bare surface and sparse vegetation are the primary source areas of blowing snow. • Greater vegetation coverage and height are areas of snow accumulation. [ABSTRACT FROM AUTHOR]

Based on observational data analyses of a Madden‐Julian Oscillation (MJO) event during the field campaign of the Years of the Maritime Continent Project, we propose a new mechanism for MJO convective initiation and propagation to which mixed Rossby‐gravity waves (MRGs) contribute significantly. The intensive observation captured midtropospheric wind variations associated with MRGs, and those signals propagated westward over the Indian Ocean in the MJO‐suppressed phase. The transition to the MJO active phase follows tight MRG‐convection coupling, which is enhanced when the wavelength becomes shorter due to weak midlevel convergence in the western Indian Ocean. Basin‐scale anomalous midtropospheric moistening caused by MRG shallow circulations also contributes. These processes lead to the lower‐tropospheric MRG wave packet formation and successive triggering of MJO convection, with the eastward MRG group velocity corresponding to MJO propagation. Additional analysis for other MJO cases implicates potential for robustness of this MJO‐MRG relationship. Plain Language Summary: Using the observational data during the field observation campaign, we propose a new mechanism about the initiation and eastward movement of tropical large‐scale cumulus convective systems called the Madden‐Julian Oscillation (MJO) by focusing on one of high‐frequency atmospheric variations in the tropics, mixed Rossby‐gravity waves (MRGs). The activation of MJO cloud systems in the western Indian Ocean follows the strong interaction between MRG dynamics and cumulus convection associated with the wavelength shortening of MRGs and broad moistening in the middle troposphere over the Indian Ocean due to MRG shallow circulations. After these processes, MRG circulations in the lower troposphere successively developed to the east, which explains the eastward propagation of MJO convective systems in the Indian Ocean. This study emphasizes the importance of the multiscale interaction between MRGs and MJO. Key Points: The field campaign captured wind variations associated with MRGs, especially in the midtroposphere during the MJO‐suppressed phaseMJO onset followed tight MRG‐convection coupling linked to wave contraction and MRG‐induced midtropospheric moistening in the Indian OceanMRG wave packet formation at the eastward group velocity causes MJO convection to the east, leading to MJO propagation over the Indian Ocean [ABSTRACT FROM AUTHOR]

The coral-dwelling damselfish Dascyllus reticulatus shows heterosexual cohabitation on branching corals and has been considered to maintain a haremic mating system, where a few males monopolize mating within the group. However, details of the group structure have not been investigated. To clarify the individual-level group structure of D. reticulatus, we conducted field observational surveys on a damselfish population on reefs of Kuchierabu-jima Island, southern Japan. Relatively large D. reticulatus inhabited corals with long branches and wide gaps with a female-biased sex ratio, and they maintained haremic groups where the largest male monopolized mating. In contrast, small adults and juveniles cohabited in higher individual densities on short-branch corals, with no bias in individual sex ratio. Only nine of 26 adult males in the short-branch coral groups showed mating activities. Nineteen of 37 adult females in the short-branch coral groups spawned, and their spawning frequency was lower than that of the females on the long-branch coral. Thus, we observed two contrasting social compositions and mating activities within harem-like cohabitation groups that depended on body size and sheltering coral structures. We observed inter-harem moves by large non-breeding individuals from the short-branch corals to the long-branch corals, implying a conditional use of the two types of groups related to body size. Our observations present a new example of multiple forms of groups in haremic reef fishes. [ABSTRACT FROM AUTHOR]

Understanding how crop phenology responds to historical climate change is a prerequisite for evaluating crop phenology and future yield responses. Most phenology response investigations are based on the phenology observed under circumstances of varieties changing over time, which then necessitates disentangling the role of climate change from the effect of changing varieties using various models. However, results from such studies are limited by the uncertainties caused by model mechanisms and assumptions and parameter calibration and validation. In this study, phenology observations were made for varieties of winter wheat (Triticum aestivum L.), rice (Oryza sativa L.), and spring maize (Zea mays L.) at 11 agro-meteorological observation sites in north China. The varieties observed for each species did not change over a period of at least 15 years. The observations were used to investigate the measured phenology response to climate. Dates of major wheat phenology stages tended to occur earlier due to warming, but the trend in rice and spring maize was not clear. Growth duration was shortened during the vegetative period of winter wheat, but was prolonged during vegetative period of rice and in the reproductive period of winter wheat and rice. Growing degree days (GDD) were generally increased for both vegetative and reproductive periods for all crops except during the vegetative period for winter wheat. We found that most trends in date of phenology stages, duration of growth phases, and GDD were similar to previous reports in which the varieties observed did not remain constant. This indicates that previous reports are likely to have overestimated the effect of cultivar shifting on crop phenology and underestimated the role of climate. Based on our results, growth duration under future warmer conditions may be longer than previously simulated, and hence yield may also be higher than previously estimated. [ABSTRACT FROM AUTHOR]