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The Qinghai–Tibet Plateau is particularly vulnerable to the effects of climate change and disturbances caused by human activity. To better understand the interactions between soil nitrogen and sulfur cycles and human activities on the plateau, the distribution characteristics of soil nitrogen and sulfur density and their influencing factors for three soil layers in Machin County at depths of 0–20 cm, 0–100 cm, and 0–180 cm are discussed in this paper. The results indicated that at depths of 0–180 cm, soil nitrogen density in Machin County varied between 1.36 and 16.85 kg/m2, while sulfur density ranged from 0.37 to 4.61 kg/m2. The effects of three factors—geological background, land use status, and soil type—on soil nitrogen and sulfur density were all highly significant (p < 0.01). Specifically, natural factors such as soil type and geological background, along with anthropogenic factors including land use practices and grazing intensity, were identified as decisive in causing spatial variations in soil nitrogen and sulfur density. Machin County on the Tibetan Plateau exhibits natural nitrogen and sulfur sinks; However, it is crucial to monitor the emissions of N2O and SO2 into the atmosphere from areas with high external nitrogen and sulfur inputs and low fertility retention capacities, such as bare land. On this basis, changes in the spatial and temporal scales of the nitrogen and sulfur cycles in soils and their source-sink relationships remain the focus of future research. [ABSTRACT FROM AUTHOR]

It is a significant technical challenge to exploit deep-sea polymetallic nodules with high efficiency and low disturbance. The mechanical behavior of seabed nodule collecting is very complicated, which is a multi-physical coupling process involving three-dimensional turbulent flow, discrete particle movement, and fine particle soil failure. In this paper, three main deep-sea hydraulic nodule collecting methods, i.e., the suck-up-based method, the Coandă-effect-based method, and the double-jet hydraulic method, are investigated by numerical simulation on the performance of nodule collecting and environmental disturbance. The realizable K-Epsilon two-layer model and the discrete element method are used to simulate the turbulent flow of the liquid phase and nodule particles in the solid phase respectively. The effect of collection flow qm and drag velocity v on collection rate η, turbulent kinetic energy k, and volume fraction φ of the seawater-sediment mixture in the collecting flow field is analyzed. The flow velocity, pressure, and nodule distribution are explored. The results indicate that, at the same qm and v, the double-jet hydraulic model will achieve the largest η, while the suck-up-based model will achieve the least η. The double-jet hydraulic model has the most significant disturbance to the near-bottom flow field and the most obvious sediment spreading phenomenon. In contrast, the suck-up-based model and the Coandăeffect-based model have less environmental disturbance, which is more conducive to the requirements of environmental protection. The Coandă-effect-based model shows minor sensitivity to qm and v and a good balance between high nodule collecting efficiency and low environmental disturbance. This paper will provide a scie.pngic basis for revealing the nodule collecting mechanism and designing and developing a nodule collecting device.

Copyright of Journal of Shanghai Jiao Tong University (1006-2467) is the property of Journal of Shanghai Jiao Tong University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An incremental deep deterministic policy gradient (IDDPG) algorithm is devised for the trajectory tracking control of a four-wing variable sweep (FWVS) aircraft with uncertainty. The IDDPG algorithm employs the line-of-sight (LOS) method for path tracking, formulates a reward function based on position and attitude errors, and integrates long short-term memory (LSTM) units into IDDPG algorithm to enhance its adaptability to environmental changes during flight. Finally, environmental disturbance factors are introduced in simulation to validate the designed controller's ability to track climbing trajectories of morphing aircraft in the presence of uncertainty. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to solve the challenging problem of automatic carrier landing with the presence of environmental disturbances. Therefore, a global fast terminal sliding mode control (GFTSMC) method is proposed for automatic carrier landing system (ACLS) to achieve safe carrier landing control. Design/methodology/approach: First, the framework of ACLS is established, which includes flight glide path model, guidance model, approach power compensation system and flight controller model. Subsequently, the carrier deck motion model and carrier air-wake model are presented to simulate the environmental disturbances. Then, the detailed design steps of GFTSMC are provided. The stability analysis of the controller is proved by Lyapunov theorems and LaSalle's invariance principle. Furthermore, the arrival time analysis is carried out, which proves the controller has fixed time convergence ability. Findings: The numerical simulations are conducted. The simulation results reveal that the proposed method can guarantee a finite convergence time and safe carrier landing under various conditions. And the superiority of the proposed method is further demonstrated by comparative simulations and Monte Carlo tests. Originality/value: The GFTSMC method proposed in this paper can achieve precise and safe carrier landing with environmental disturbances, which has important referential significance to the improvement of ACLS controller designs. [ABSTRACT FROM AUTHOR]

We update the list of indigenous mammals known from each of Western Australia's mainland bioregions since European settlement, assess their regional status in terms of extent of occurrence, then compare these regional status lists and derived faunal attrition values with those published in 2006. Seven bioregions show substantially more faunal attrition since 2006, including the Avon Wheatbelt, Victoria Bonaparte and Northern Kimberley. The status of 27 species has worsened in at least one bioregion, an average of 1.7 species per bioregion across the 26 bioregions. We also examine potential explanatory factors associated with faunal attrition across the bioregions using beta regression and AIC-based model selection. Faunal attrition was strongly associated with low average annual rainfall, a low proportion of species that shelter in rockpile habitat, high environmental change, a high proportion of species in the 'Critical Weight Range' and, to a lesser degree, a high proportion of omnivorous species. Only conservation management outside of havens can reverse this downward trend. [ABSTRACT FROM AUTHOR]

Urbanization leads to habitat degradation, fragmentation, and exposes organisms to materials that may be unfamiliar to them. This may alter not only their presence and abundance but also their behaviour. Many birds that inhabit urban and semi-urban areas have been reported to utilize Anthropogenic Waste Materials (AWM) for nest construction. In this study, we examine the use of AWM in nest construction and how it varies among birds within a community. We dissected abandoned bird nests and quantified the amount of AWM in each architectural component, viz., structural, anchoring, and inner lining. The maximum amount of AWM usage was noted in the structural part of the nest. We further explored if the amount of AWM available in the environment was correlated with their usage towards nest construction. We show that the amount of AWM available in the habitat decreased over the course of our study, and this was reflected in the amount of AWM utilized by the birds in nest construction. Our study shows that urban waste management can reduce the utilization of AWMs by birds in their nests, and we recommend that in urban environments, native plants that may act as natural nesting materials should be preserved and planted to replace the usage of AWMs. [ABSTRACT FROM AUTHOR]

To solve the problems of unsmooth path planning, insufficient dynamic obstacle avoidance ability, and environmental disturbance effect on the path planning result, this paper proposes a smooth path planning method for unmanned surface vessels (USVs) considering environmental disturbance. First, an improved A* algorithm, which uses the path smoothing method based on the minimum turning radius of a USV, is proposed for global path planning. The binary tree method is used instead of the enumeration method to select a relatively optimal path in the current situation to improve algorithm efficiency. In addition, the dynamic window approach (DWA) with the Convention on the International Regulation for Preventing Collision at Sea (COLREGs) constraints is used for local path planning. The dist function in the DWA algorithm is improved to enhance the DWA algorithm's ability to avoid dynamic obstacles. Finally, the environmental disturbance function is derived and added to the A* and DWA algorithms to handle the effect of environmental disturbances, such as water flow, on the path planning result, which can significantly improve the path-planning ability of the algorithm in the presence of environmental disturbances. Simulation experiments are performed in three scenarios to verify the proposed algorithm. The experimental results show that compared with the other algorithms, the proposed algorithm can effectively avoid dynamic obstacles and reduce the impact of environmental disturbance on the path planning result. At the same time, the proposed algorithm has high efficiency and strong robustness. [ABSTRACT FROM AUTHOR]

Copyright of Al-Anbar University Journal of Economic & Administration Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A well-known problem of visual object tracking is the difficulty of accurately estimating the object trajectory under conditions of environmental disturbances in the bounding box (BB) of a video camera. In this paper, we consider BB variations as Gaussian-Markov colored measurement noise (CMN). In order to perform accurate tracking in the presence of CMN, we use measurement differencing and develop a robust general unbiased finite impulse response (GUFIR) filter and use the general Kalman filter (GKF) as a benchmark. The GUFIR and GKF algorithms are tested by the “Car4” benchmark. It is shown that, in terms of the tracking precision and under the heavy disturbance with the $0.65 \leqslant \Psi \leqslant 0.95$ coloredness factor, the best tracking performance is achieved using the robust GUFIR filter. When $\Psi < 0.6$ , the GUFIR and GKF algorithms perform near equally. In the extreme point of $\Psi = 1.0$ , where the Gauss-Markov CMN loses the stationarity, both algorithms provide zero precision and become inefficient. In general, it is concluded that the GUFIR filter, which ignores any zero mean disturbance and initial values, is much more suitable for applications in visual object tracking than Kalman-like algorithms relying on complete object information.

Animal ecology and evolution are shaped by environmental perturbations, which are undergoing unprecedented alterations due to climate change. Fire is one such perturbation that causes significant disruption by causing mortality and altering habitats and resources for animals. Fire regimes are changing on a global scale, but the effects of these changes on animal communities are poorly understood. Arthropods are one of the most ubiquitous and diverse animal taxa on the planet and their populations are sensitive to environmental change. Given their wide‐ranging impacts on ecosystem functioning, a better understanding of arthropod responses to changing fire regimes is critical and may also provide more general insights into how other groups might respond to fire.Here, we provide a comprehensive meta‐analytical assessment of how fire influences the arthropod community across habitats and functional groups. Using data from 130 peer‐reviewed papers across the globe, we tested how a variety of fire characteristics, including management regime, severity and time‐since‐fire affect arthropod populations and communities across habitats.Our results show that arthropod communities display substantial variation in response to fire and that community‐level responses are most likely to be detected within the first year. Responses also vary depending on fire characteristics and habitat. Specifically, while community metrics such as diversity were increased by low severity fires, they were reduced by high severity fires. Likewise, evenness increased after prescribed burns but was reduced after wildfire. Measures of arthropod community structure decreased following fires in deserts and forests.Across the entire arthropod community, fire also had variable effects on community diversity. Fire tended to have a negative effect size on arthropods across life stages, but responses did vary among groups. Nearly all functional groups exhibited a negative response to fire with the exception of herbivores, for which abundance, diversity and richness increased after fire.Our results suggest that the increasing prevalence of high‐severity wildfires are changing the structure of arthropod communities. Given their ubiquitous presence and diverse roles in terrestrial ecosystems, these community changes are likely to affect ecosystem functioning in various ways, including through increased herbivory. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

In this study, basic research was conducted regarding the era of autonomous vessels and artificial intelligence (deep learning, big data, etc.). When a vessel is navigating autonomously, it must determine the optimal route by itself and accurately follow the designated route using route-following control technology. First, the optimal route should be generated in a manner that ensures safety and reduces fuel consumption by the vessel. To satisfy safety requirements, sea depth, under-keel clearance, and navigation charts are used; algorithms capable of determining and shortening the distance of travel and removing unnecessary waypoints are used to satisfy the requirements for reducing fuel consumption. In this study, a reinforcement-learning algorithm-based machine learning technique was used to generate an optimal route while satisfying these two sets of requirements. Second, when an optimal route is generated, the vessel must have a route-following controller that can accurately follow the set route without deviation. To accurately follow the route, a velocity-type fuzzy proportional–integral–derivative (PID) controller was established. This controller can prevent deviation from the route because overshoot rarely occurs, compared with a proportional derivative (PD) controller. Additionally, because the change in rudder angle is smooth, energy loss by the vessel can be reduced. Here, a method for determining the presence of environmental disturbance using the characteristics of the Kalman filter innovation process and estimating environmental disturbance with a fuzzy disturbance estimator is presented, which allows the route to be accurately maintained even under conditions involving environmental disturbance. The proposed approach can automatically set the vessel's optimal route and accurately follow the route without human intervention, which is useful and can contribute to maritime safety and efficiency improvement. [ABSTRACT FROM AUTHOR]

Copyright of Adab Al-Kufa is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper is on cooperative localization and control of multiple heterogeneous robots utilizing a string formation. This formation is preferred, since robots can move along a narrow passage utilizing this formation. Dead reckoning localization based on inertial measurement units leads to accumulated localization error. To avoid the error accumulation in dead reckoning localization, this paper introduces the last‐move strategy for multiple heterogeneous robots. In the last‐move strategy, a single robot is selected for maneuvering, and it turns on its bearing‐range sensors for a short amount of time, in order to locate itself. While the selected robot moves, all other robots stop moving and perform as static landmarks for the moving robot. A robot may not maintain its desired course, in the case where environmental disturbance is severe. We thus develop a control strategy for avoiding obstacles while estimating the disturbance direction at a robot's location. To the best of our knowledge, this paper is novel in localization and control of a team of heterogeneous robots, considering the case where environmental disturbance is severe. The proposed localization process is energy‐efficient, thus is suitable for practical applications. The performance of the proposed schemes is demonstrated utilizing MATLAB simulations. [ABSTRACT FROM AUTHOR]

Globally, habitat loss and land conversion are major drivers of bird population decline. To halt the decline, it is essential that habitat conservation and restoration efforts are based on an understanding of how individual species use their habitat. Here, we examine habitat use by Red-winged Blackbirds (Agelaius phoeniceus) by quantifying their probability of occurrence in different land cover types and in association with varying degrees of habitat modification across most of the species' range. To do so, we used the citizen-science eBird dataset, in combination with MODIS land cover data to model site occupancy for two breeding seasons and related presence/absence to the Global Human Modification Index. We found that Red-winged Blackbirds occupy rural and suburban habitats at higher probabilities than they do habitats with high levels of urbanization, and at similar or higher probabilities than they do their historic, natural habitats. Furthermore, we found that occurrence probability peaks at intermediate values of the Global Human Modification Index. The results were consistent across most ecoregions and the geographic range of the species, confirming that the Red-winged Blackbird is a suburban-adaptable species, persisting in moderately disturbed environments. Although more research is needed to understand the ecological and evolutionary consequences of this pattern of habitat use, our results provide novel data on Red-winged Blackbird habitat use in the midst of increasing urbanization. More broadly, they provide insight into how common, widespread avian species may be affected by anthropogenic disturbance and highlight the importance of rural and suburban environments in urban ecology and evolution. [ABSTRACT FROM AUTHOR]

Based on the observation data of SS-Y extensometer at Yixian Seismic Station from 2014 to 2021, five typical events disturbed by the environment are analyzed, combined with the tectonic stress background field of Yixian deformation cave and the quantitative calculation of the model. The following conclusions are obtained: ① The load strain caused by the load interference source on the observation data of the extensometer at Yixian Station is related to the distance and load of the interference source and is positively correlated; ② The SS-Y extensometer of Yixian Station is divided into three parts, where the NS test item and the NE test item are subjected to the abnormal amplitude of load disturbance curve. ③ The results of three-dimensional model simulation of interference sources are smaller than those of anomalous variables.

Wind power generation prediction plays an important role in the safety and economic operation of the power system. There are many parameters recorded in wind farm data, such as wind power, wind speed, wind direction, and so on. Traditional wind power prediction modeling methods lack the mining of these parameter data and fail to make good use of some potential physical information. To address this challenge, this paper proposes a multiview neural network learning framework to predict wind power. One is the data attribute view of wind power, which uses the historical data feature of the wind power itself to learn the future wind power feature. The other is the physical attribute view of wind power, which uses the physical attribute features associated with the wind power definition to learn the future features. Then all the learned features are jointly fused to predict the future wind power values. In addition, an uncertain factor is proposed and computed, which is inspired by the wind power formula and usually associated with internal and external environment perturbation. All time series features are input into the gated recurrent unit neural network to form a hybrid neural network framework for wind power prediction. Experimental results under the measured condition and the standard condition of wind farms demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Aim: Coastal habitats are among the most dynamic environments on earth and are highly vulnerable to large‐scale physical disturbance. Genetic studies of nearshore marine species are revealing long‐lasting signatures of major coastal disturbance events. We synthesize emerging data to highlight how physical perturbations can impact the phylogeographic patterns of coastal populations. Taxon: Coastal marine and estuarine taxa. Location: Coastal regions around the globe. Methods: We synthesize coastal genetic and genomic literature, focussing particularly on the phylogeographic consequences of natural disturbance events including uplift, tsunami, hurricanes, glaciations and sea‐level fluctuations. We focus on studies with clear physical analytical frameworks constrained by abiotic data. Results: Tectonic and atmospheric disruptions can be considered shot‐term events with major impacts on populations adjacent to the centre of disturbance, typically resulting in the evolution of shallow phylogeographic patterns. Long‐lived climate‐driven disturbances such as glaciations, however, operate over vast geographic scales and often drive deep evolutionary patterns in affected populations. We show that studies using genome‐wide data could better identify fine‐scale signatures of both past and contemporary habitat perturbations. Conclusions: Recent data reveal the interplay between physical upheaval and coastal phylogeography, indicating that disturbance can affect diversity, connectivity and demography of coastal populations. The interplay between long‐lived large‐scale disturbance and species‐specific biotic traits has shaped deep phylogeographic patterns of coastal taxa. Additionally, it could be argued that, at least for some regions, short‐term disturbance is the 'rule' rather than the 'exception', and thus, represents a key driver of coastal genetic patterns in disturbance prone coastal regions. Geo‐genomic approaches that combine genome‐wide data with explicit habitat models or disturbance history information have been particularly successful in explaining the drivers of coastal evolutionary change. We argue that future integration of genomic and physical data will be crucial for tracing evolutionary trends in fast‐changing marine environments. [ABSTRACT FROM AUTHOR]

ABSTRACT Global climate change has emerged as a critical environmental problem. Different types of climate extremes drive soil microbial communities to alternative states, leading to a series of consequences for soil microbial ecosystems and related functions. An effective method is urgently needed for buffering microbial communities to tackle environmental disturbances. Here, we conducted a series of mesocosm experiments in which the organic (NOF) and chemical fertilizer (NCF) long-term-amended soil microbiotas were subjected to environmental disturbances that included drought, flooding, freeze-thaw cycles, and heat. We subsequently tracked the temporal dynamics of rare and abundant bacterial taxa in NOF and NCF treatment soils to assess the efficiencies of organic amendments in recovery of soil microbiome. Our results revealed that freeze-thaw cycles and drought treatments showed weaker effects on bacterial communities than flooding and heat. The turnover between rare and abundant taxa occurred in postdisturbance succession of flooding and heat treatments, indicating that new equilibria were tightly related to the rare taxa in both NCF and NOF treatment soils. The Bayesian fits of modeling for the microbiome recovery process revealed that the stability of abundant taxa in NOF was higher than that in NCF soil. In particular, the NOF treatment soil reduced the divergence from the initial bacterial community after weak perturbations occurred. Together, we demonstrated that long-term organic input is an effective strategy to enhance the thresholds for transition to alternative states via enhancing the stability of abundant bacterial species. These findings provide a basis for the sustainable development of agricultural ecosystems in response to changing climates. IMPORTANCE Different climate extremes are expected to be a major threat to crop production, and the soil microbiome has been known to play a crucial role in agricultural ecosystems. In recent years, we have known that organic amendments are an effective method for optimizing the composition and functioning of the soil microbial community and maintaining the health of the soil ecosystem. However, the effects of organic fertilization on buffering bacterial communities against environmental disturbances and the underlying mechanisms are still unclear. We conducted a series of mesocosm experiments and showed that organic fertilizers had additional capacities in promoting the soil microbiome to withstand climate change effects. Our study provides both mechanistic insights as well as a direct guide for the sustainable development of agricultural ecosystems in response to climate change.

[Display omitted] • An exact and low-impact means for ecohydrological survey in wetlands is verified. • Onsite tests for water interaction and exchanges prove the process effectiveness. • Water balance model indicates the groundwater losses and management implications. • The powerful tools suggest to replace conventional methods in habitat ecohydrology. Comprehending the hydrological conditions in wetlands is a critical aspect of successfully enhancing wetland conservation. The interaction between wetland surface water and groundwater is a complex process, requiring detailed onsite hydrological and soil surveys, laboratory experiments, and modeling to clarify this relationship. However, conventional investigation methods often cause significant disruptions and thus may affect the natural environment and compromise data reliability. In this study, a high-accuracy and low-environmental-disturbance (LED) approach was proposed involving modified falling head permeability and modified seepage meter tests to elucidate the groundwater characteristics in an ecological reserve. A water balance (WB) calculation method was employed to examine the performance of the proposed LED approach. The results revealed that the LED performed better than conventional methods in hydraulic conductivity and seepage velocity exploration, thereby improving the accuracy of quantifying groundwater flow. Moreover, the experimental findings and ecohydrological observations were used to assess the groundwater flow regime, and the data were consistent with the field survey results. The contradiction between conducting research and protecting ecological reserves can pose difficulties in the sustainable and effective management of wetlands. The LED approach can be applied broadly, especially in areas where significant disturbance should be avoided. The water budget model can thus be developed to help deduce the interaction between groundwater and surface water. We suggest that these innovative methods are effective tools and can assist both scientists and authorities in formulating corresponding habitat management strategies. [ABSTRACT FROM AUTHOR]

• A stochastic dynamical system is developed to describe the microbial batch culture with environmental disturbances. • To guarantee model refinement and biological robustness simultaneously, a parameter identification model is proposed. • The model is converted to optimization problems with LMI-constraints under the help of the T-S fuzzy approximation. • For this fermentation process, some new results on random environmental disturbance distribution are obtained. This paper considers the mathematical modeling and parameter identification of glycerol bioconversion to 1,3-Propanediol in the batch fermentation. Taking into account the characteristic of inherently genetic stochasticity and environmental disturbances in this biochemical system, a stochastic differential system with disturbance is proposed to describe this microbial fermentation process. To guarantee the model refinement and the biological robustness simultaneously, a multi-objective parameter identification model is proposed. To obtain the optimal parameters, the multi-objective optimization problem is converted to a sequence of single-objective optimization problems. Then, the problems are further approximated to a sequence of the optimization problems with linear matrix inequality constraints under the help of the T-S fuzzy approximation. Finally, the optimization problems were solved by using the linear matrix inequality optimization techniques. Numerical results show that the proposed stochastic dynamical system is fit to describe this batch process and our proposed method of parameter identification is also feasible. [ABSTRACT FROM AUTHOR]

Functional diversity has been defined as the value, range, distribution, and relative abundance of the functional traits of individuals that belong to an ecosystem. Thus, the functional response of organisms to environmental disturbances depends largely on their functional traits.Here, we evaluated dung beetle functional diversity associated to the Atlantic Forest replacement using a matrix with 25 functional traits (10 morphological, four ethological, and 11 physiological). We compared functional diversity among native and disturbed habitats with a multi and single trait approach.Contrary to previous studies, habitats with higher disturbance (open pasture) exhibited higher functional diversity compared to native forests, which could be explained by the incorporation of physiological response traits. Species of open disturbed habitats showed extreme values of such traits, explaining the observed pattern.The inclusion of several traits that represent both species ecology and morphology, and their physiology, generates different results to those observed in previous functional studies. This highlights the importance of including a large variety of functional traits in future functional diversity studies.We propose that functional traits must (1) be carefully chosen according to their biological and functional basis; (2) represent species ecology and physiology; and (3) include both effect and response traits. In addition, we consider it is extremely relevant to include a multi and single trait approach in functional diversity studies. A combination of all these considerations will provide a more realistic and complete overview of functional diversity patterns and the potential consequences of human disturbance on ecosystem functioning. [ABSTRACT FROM AUTHOR]

The Amazon rainforest is considered the largest reservoir of culicids and arboviruses in the world. It has been under intense human‐driven alteration, especially in the so‐called 'Arc of Deforestation', located in the eastern and southern regions. The emergence and transmission of infectious diseases are increasing, potentially due to land‐use change. We used landscape‐scale mosquito surveillance across a forest fragmentation gradient in the southern Amazon to evaluate the relationship between forest disturbance and the composition and structure of mosquito communities with a particular focus on the potential for arbovirus emergence in the region. Generalized linear models and logistic regression were used to associate the degree of landscape disturbance with arbovirus vectors' richness and abundance. A total of 1,960 culicids, belonging to 50 species, were collected from 2015 to 2016. Among these species, 20 have been associated with the transmission of arboviruses. Our results show an association of land use, more specifically small size of forest remnants with more irregular shape and higher edge density, with the increase of arbovirus vectors' richness and abundance. Six species of mosquito vectors exhibited a higher probability of occurrence in landscapes with medium or high degrees of disturbance. Our results indicate that land‐use change influences mosquito communities with potential implications for the emergence of arboviruses. [ABSTRACT FROM AUTHOR]

To increase visitor footfall and engagement, zoos may host public events that may extend outside typical opening hours. With plans to hold a 2‐day concert at Tayto Park, Ireland, this study aimed to identify the behavioral response to the music event of a selected group of species in the zoo. Twenty‐two species were observed across three phases of the event (pre‐, during, and post event). Specific behaviors of interest were categorized as active, resting, asleep, abnormal, and out of sight, with repeated observations being made at each enclosure during each phase. Alongside these behavioral data, sound pressure levels (SPLs) were concurrently recorded at the observation locations in terms of both dB(A) and dB(C). The median dB(C) levels during the event were found to be significantly higher (mdn = 64.5 dB) when compared with both pre‐event (mdn = 60.7 dB) and postevent phases (mdn = 59.4 dB), while dB(A) levels were only significantly higher during the event (51.7 dB) when compared with the pre‐event phase (mdn = 49.8 dB). We found some species‐specific behavioral changes (mainly associated with active and resting behaviors) correlated with increased SPLs and/or event itself. However, the behavioral responses varied between species and there were numerous species that did not respond with any change in behavior to the increased SPLs or the event itself. This variation in response across species reinforces the need for monitoring of behavioral changes as well as consideration of their natural behavioral ecology when implementing appropriate mitigation strategies. Further research should be encouraged to provide an evidence‐based assessment of how music events may affect animal welfare and behavior and to test the efficacy of mitigation strategies that are implemented to safeguard animal welfare. Highlights: We found several species expressed behavioral changes that correlated with increased noise and/or other aspects of a public event. The nature of these responses varied across species. Many species did not show any change in behavior during the event.Habitual resting/active periods may have changed due to extended opening hours. The onset of sleep behavior in vultures occurred later during the event compared with the pre‐event phase. Porcupines emerged from their dens later during the event compared to pre‐ or postevent phases.Predetermined maximum sound pressure limits for animal enclosures were not exceeded, confirming that precautionary measures, that is, soundproofing, location, stage position, and other mitigations, provided effective control of noise propagation in the zoo. [ABSTRACT FROM AUTHOR]

Tropical forests have a great potential for the exploitation of natural resources. Among the economic activities that depend on forest resources, timber production is the most important one. Nevertheless, these activities may negatively affect wildlife, the availability of natural resources, and ecosystem process. Here we analysed the effects of low-impact logging on understory bird species richness, number of individuals captured, species composition, and assemblage structure in central Brazilian Amazon. We compared logged and unlogged areas over a period of three years (from August 2014 to May 2017). We captured a total of 180 birds and 42 species (20 families) in the logged area and 226 birds and 49 species (20 families) in the unlogged area. Bird assemblage structure in the logged area changed more intensely over the three years of study and became more similar to the assemblage found in the unlogged area. The degree of similarity (Jaccard’s index) in species composition between logged and unlogged areas increased from 18% in the third year to 39% in the fifth year after logging. The results suggest that the minor effects of low-impact logging were reduced a few years after the disturbance, probably due to ecological succession. The proximity of logged and unlogged areas and the reduced impact in the study site may facilitate the recovery of the bird assemblage after the disturbance.

In this paper, a differential phase-modulated interferometer (DPMI) is proposed to compensate for the rotational error for precision displacement measurement. In DPMI, a reference interferometer sharing the same reference arm with the measurement interferometer is constructed. Using the two interferometers to differentially measure the displacement, the unbalanced environmental disturbance on the measurement can be minimized. An integrated 2 × 2 array photodetector (APD) is adopted in DPMI. Based on APD with differential wavefront sensing (DWS) technology, the rotation angle can be detected and compensated. Therefore, precision displacement without rotational error and unbalanced environmental disturbance can be achieved. Three confirmatory experiments were performed, and the experimental results show that the maximum displacement drift is reduced from 902.9 nm to 16.3 nm in 100 min stability test, the standard deviations between the pitch and yaw angles obtained by DPMI and Renishaw interferometer are 1.68 × 10−5° and 1.86 × 10−5°, respectively, and the maximum deviation between the measurement result of DPMI and the stage positioning before and after angle compensation is reduced from 5.207 μm to about 0.719 μm. [ABSTRACT FROM AUTHOR]

Background and Aims Self-fertilization is often associated with ecological traits corresponding to the ruderal strategy, and selfers are expected to be less competitive than outcrossers, either because of a colonization/competition trade-off or because of the deleterious genetic effects of selfing. Range expansion could reduce further competitive ability while polyploidy could mitigate the effects of selfing. If pollinators are not limited, individual fitness is thus expected to be higher in outcrossers than in selfers and, within selfers, in polyploids than in diploids. Although often proposed in the botanical literature and also suggested by meta-analyses, these predictions have not been directly tested yet. Methods In order to compare fitness and the competitive ability of four Capsella species with a different mating system and ploidy level, we combined two complementary experiments. First, we carried out an experiment outdoors in north-west Greece, i.e. within the range of the obligate outcrossing species, C. grandiflora , where several life history traits were measured under two different disturbance treatments, weeded plots vs. unweeded plots. To better control competition and to remove potential effects of local adaptation of the outcrosser, we also performed a similar competition experiment but under growth chamber conditions. Key Results In the outdoor experiment, disturbance of the environment did not affect the phenotype in any of the four species. For most traits, the obligate outcrossing species performed better than all selfing species. In contrast, polyploids did not survive or reproduce better than diploids. Under controlled conditions, as in the field experiment, the outcrosser had a higher fitness than selfing species and was less affected by competition. Finally, contrary to the outdoor experiment where the two behaved identically, polyploid selfers were less affected by competition than diploid selfes. Conclusions In the Capsella genus, selfing induces lower fitness than outcrossing and can also reduce competitive ability. The effect of polyploidy is, however, unclear. These results highlight the possible roles of ecological context in the evolution of selfing species. [ABSTRACT FROM AUTHOR]

This study assessed invertebrate response to disturbances in the riparian zone of the Wewe river, using geometric series, rarefaction, Renyi diversity, and CCA models. We sampled 2,077 individuals (dry season) and 2,282 (wet season) belonging to 16 invertebrate orders. The severely disturbed habitat registered the highest individuals (n = 1,999), while the least was the moderately disturbed habitat (n = 740). Seasonal assemblages were not significantly different. Fire, farming, tree felling, and erosion explained 66.8% and 60.55% in the dry and wet seasons, respectively, of variations in invertebrate assemblages. This suggests threats to the invertebrate community and the riparian ecosystem health by anthropogenic interventions.

In this study, basic research was conducted regarding the era of autonomous vessels and artificial intelligence (deep learning, big data, etc.). When a vessel is navigating autonomously, it must determine the optimal route by itself and accurately follow the designated route using route-following control technology. First, the optimal route should be generated in a manner that ensures safety and reduces fuel consumption by the vessel. To satisfy safety requirements, sea depth, under-keel clearance, and navigation charts are used; algorithms capable of determining and shortening the distance of travel and removing unnecessary waypoints are used to satisfy the requirements for reducing fuel consumption. In this study, a reinforcement-learning algorithm-based machine learning technique was used to generate an optimal route while satisfying these two sets of requirements. Second, when an optimal route is generated, the vessel must have a route-following controller that can accurately follow the set route without deviation. To accurately follow the route, a velocity-type fuzzy proportional–integral–derivative (PID) controller was established. This controller can prevent deviation from the route because overshoot rarely occurs, compared with a proportional derivative (PD) controller. Additionally, because the change in rudder angle is smooth, energy loss by the vessel can be reduced. Here, a method for determining the presence of environmental disturbance using the characteristics of the Kalman filter innovation process and estimating environmental disturbance with a fuzzy disturbance estimator is presented, which allows the route to be accurately maintained even under conditions involving environmental disturbance. The proposed approach can automatically set the vessel’s optimal route and accurately follow the route without human intervention, which is useful and can contribute to maritime safety and efficiency improvement.

Industrial assets exposed to random environment often exhibit complex deterioration mechanisms with health status variations. In actual field operation, hidden defect signals are usually crucial indicators of upcoming malfunctions and also reminders of proactive maintenance executions. Despite the extensive applications of defect-centered maintenance, in the literature, little attempt has: a) captured the impact of random environments on health variation and restoration, and b) explored the differentiated functions of maintenance windows in separate states. This article addresses these challenges by introducing a state-based maintenance policy with multifunctional maintenance windows. The impact of environmental disturbance on both defect initialization and propagation is characterized by random increment of the state transition rate as well as probabilistic malfunction risk. Three types of maintenance windows (regular, opportunistic, and postponed) are scheduled to ensure a flexible scheduling of inspection and spare part resources. Importantly, the function of opportunistic window is state-based, defect identification when normal and removal when defective. The objective is to minimize the cost rate via the joint optimization of inspection interval, postponed interval, and opportunistic threshold. Experimental studies demonstrate the superior performance of this policy over some conventional policies. [ABSTRACT FROM AUTHOR]

Abstract Ecosystems are experiencing elevated levels of disturbance, and species with narrower niches are often more vulnerable to disturbances. Niche breadth is often measured in terms of either diet or habitat use but diet and spatial use are infrequently considered in tandem. These different aspects of niche breadth potentially expose species to different types of disturbances; species with narrow dietary niches may be more affected by disturbances that alter trophic relationships, while species with narrow habitat niches may be more vulnerable to habitat loss and point‐source pollutants. We examined dietary and habitat niche breadth of common bottlenose dolphins, Tursiops truncatus truncatus, from three different nearshore sites in the Gulf of Mexico (GoM). Using stable isotopes, we determined proportional contributions of different prey groups to dolphin diets at each site and through time at one site. We used satellite‐linked telemetry at two sites to determine habitat use and site fidelity. Additionally, we examined the literature on cetacean diet, habitat use, movement, and IUCN status to determine relationships between niche breadth and population status for different species. Dolphin diets varied among sites as available prey varied, but Perciformes fish were the most frequently consumed prey. At the site for which we had temporal data, dolphins consumed more cephalopods in 2015 and 2018 but otherwise consumed primarily Perciformes fish. Dolphins had small utilization distributions and exhibited high site fidelity. Data from 31 cetacean species revealed that most species with vulnerable, threatened, or endangered IUCN statuses not only have specialized diets but also exhibit high site fidelity. Dolphins had diet characteristic of flexible generalists but were habitat specialists with high site fidelity. Dolphin populations in the GoM may have altered their diets in response to environmental changes that have altered community composition and trophic dynamics. On the other hand, their high site fidelity has exposed them to point‐source pollutants, such as oil spills, persistent organic pollutants, and freshwater. Our broader analysis of cetaceans confirmed that species with specialized diets and high site fidelity were the most vulnerable to disturbances, providing a framework to predict which nearshore dolphin populations, and cetaceans in general, are most vulnerable to environmental changes.

Ecosystems are experiencing elevated levels of disturbance, and species with narrower niches are often more vulnerable to disturbances. Niche breadth is often measured in terms of either diet or habitat use but diet and spatial use are infrequently considered in tandem. These different aspects of niche breadth potentially expose species to different types of disturbances; species with narrow dietary niches may be more affected by disturbances that alter trophic relationships, while species with narrow habitat niches may be more vulnerable to habitat loss and point‐source pollutants. We examined dietary and habitat niche breadth of common bottlenose dolphins, Tursiops truncatus truncatus, from three different nearshore sites in the Gulf of Mexico (GoM). Using stable isotopes, we determined proportional contributions of different prey groups to dolphin diets at each site and through time at one site. We used satellite‐linked telemetry at two sites to determine habitat use and site fidelity. Additionally, we examined the literature on cetacean diet, habitat use, movement, and IUCN status to determine relationships between niche breadth and population status for different species. Dolphin diets varied among sites as available prey varied, but Perciformes fish were the most frequently consumed prey. At the site for which we had temporal data, dolphins consumed more cephalopods in 2015 and 2018 but otherwise consumed primarily Perciformes fish. Dolphins had small utilization distributions and exhibited high site fidelity. Data from 31 cetacean species revealed that most species with vulnerable, threatened, or endangered IUCN statuses not only have specialized diets but also exhibit high site fidelity. Dolphins had diet characteristic of flexible generalists but were habitat specialists with high site fidelity. Dolphin populations in the GoM may have altered their diets in response to environmental changes that have altered community composition and trophic dynamics. On the other hand, their high site fidelity has exposed them to point‐source pollutants, such as oil spills, persistent organic pollutants, and freshwater. Our broader analysis of cetaceans confirmed that species with specialized diets and high site fidelity were the most vulnerable to disturbances, providing a framework to predict which nearshore dolphin populations, and cetaceans in general, are most vulnerable to environmental changes. [ABSTRACT FROM AUTHOR]

Abstract Background Mobile organisms in marine environments are expected to modify their behavior in response to external stressors. Among environmental drivers of animal movement are long-term climatic indices influencing organism distribution and short-term meteorological events anticipated to alter acute movement behavior. However, few studies exist documenting the response of vagile species to meteorological anomalies in coastal and marine systems. Methods Here we examined the movements of Eastern brown pelicans (Pelecanus occidentalis carolinensis) in the South Atlantic Bight in response to the passage of three separate hurricane events in 2 years. Pelicans (n = 32) were tracked with GPS satellite transmitters from four colonies in coastal South Carolina, USA, for the entirety of at least one storm event. An Expectation Maximization binary Clustering algorithm was used to discretize pelican behavioral states, which were pooled into ‘active’ versus ‘inactive’ states. Multinomial logistic regression was used to assess behavioral state probabilities in relation to changes in barometric pressure and wind velocity. Results Individual pelicans were more likely to remain inactive during tropical cyclone passage compared to baseline conditions generally, although responses varied by hurricane. When inactive, pelicans tended to seek shelter using local geomorphological features along the coastline such as barrier islands and estuarine systems. Conclusions Our telemetry data showed that large subtropical seabirds such as pelicans may mitigate risk associated with spatially-extensive meteorological events by decreasing daily movements. Sheltering may be related to changes in barometric pressure and wind velocity, and represents a strategy common to several other classes of marine vertebrate predators for increasing survival probabilities.

The aim of this paper was to determine the species diversity and frequency of foraging performed by bees in fragment of degraded forest in a Cerrado-Atlantic Forest ecotone area, also considering the nesting habit of each species. The foraging frequency of each bee species in the main floral sources was recorded for 12 consecutive months. The nesting site was used to sort the bees into guilds: above-ground nesting bees, ground-nesting bees, and both below and above-ground nesting bees. The guild of ground-nesting bees had 24 species and accounted for 17.48 % of the foraging rate, while above-ground nesting bees were represented by 12 species which made 8.89 % of the foraging rate, and both below and above-ground nesting bees comprised five species which made 0.43 % of the foraging rate. Africanized honeybee performed 73.20 % of the foraging flight, and presented a broad food niche. Therefore, in the forest fragment studied, two types of impacts which make difficult the survival and maintenance of the native bee fauna were observed: the dominance over floral resources by the exotic species the Africanized honeybees; the small number of large trees.

In this paper, a differential phase-modulated interferometer (DPMI) is proposed to compensate for the rotational error for precision displacement measurement. In DPMI, a reference interferometer sharing the same reference arm with the measurement interferometer is constructed. Using the two interferometers to differentially measure the displacement, the unbalanced environmental disturbance on the measurement can be minimized. An integrated 2 × 2 array photodetector (APD) is adopted in DPMI. Based on APD with differential wavefront sensing (DWS) technology, the rotation angle can be detected and compensated. Therefore, precision displacement without rotational error and unbalanced environmental disturbance can be achieved. Three confirmatory experiments were performed, and the experimental results show that the maximum displacement drift is reduced from 902.9 nm to 16.3 nm in 100 min stability test, the standard deviations between the pitch and yaw angles obtained by DPMI and Renishaw interferometer are 1.68 × 10−5° and 1.86 × 10−5°, respectively, and the maximum deviation between the measurement result of DPMI and the stage positioning before and after angle compensation is reduced from 5.207 μm to about 0.719 μm.

Organisms living in hot, arid environments face important risks associated with hyperthermia and dehydration which are expected to become more severe with climate change. To mitigate these risks, individuals often modify behaviour, e.g. reducing activity and seeking shade. These behavioural modifications may affect interactions between individuals, with consequences for the social structure of groups. We tested whether the social structure of cooperative groups of sociable weavers Philetairus socius varied with environmental temperature. We recorded the nature and frequency of interactions at feeders positioned beneath three sociable weaver colonies (n = 49 identified birds) in the Kalahari Desert with respect to environmental temperatures over a 30‐day period. Using random forest models, we examined whether thermal conditions predicted variation in social network structure. We also conducted focal observations of individual weavers to assess functional links between temperature, intensity of heat dissipation behaviour (panting) and immediate effects on social behaviour. Our results suggest that the social structure of weaver colonies becomes less cohesive and more fragmented at extreme and variable environmental temperatures. These changes in network structure appear to be linked with individuals' heat dissipation behaviour: extreme and variable temperatures were associated with increased panting, which was significantly correlated with an immediate reduction in the frequency of association. Collectively, our results indicate that interactions within groups could be disturbed by environmental temperature variation and extremes. Changing temperature regimes could therefore affect the functioning of animal societies by altering social networks. [ABSTRACT FROM AUTHOR]

Animals that face natural and human-mediated landscape disturbance processes can demonstrate different modalities of phenotypic variation to influence local population persistence. Differences in the frequency and pervasiveness of environmental variation can cause an individual's phenotype to demonstrate either directional plasticity (i.e., environmental matching), canalization, or increased trait variance. Furthermore, how important a trait's influence is on fitness can further mediate the nature of phenotypic outcomes to environmental variation. We explored the effects of multi-decadal chronosequences of logging and fire-related forest disturbance on morphological variation of the generalist lizard species, the Yellow-bellied water skink (Eulamprus heatwolei) in Southern Australia. There was evidence that both logging and fire-related disturbance could influence multiple elements of vegetation structure that would construe a major source of environmental variation for lizards. Nevertheless, neither logging nor fire-related disturbance effects resulted in significant differences in lizard morphological traits. However, there was evidence that years post-fire disturbance was associated with a modest but significant increase in a measure of lizard morphological variance. For the most part, we suggest that lizards exhibit canalization in their morphological responses to disturbance related environmental variation. In forests ecosystems with complex temporal and spatial regimes of environmental variation, canalization of lizard morphology could be expected to ensure phenotypic stability within or across generations to favor geometric, over arithmetic, fitness. [ABSTRACT FROM AUTHOR]

In many regions across the globe, extreme weather events such as storms have increased in frequency, intensity, and duration due to climate change. Ecological theory predicts that such extreme events should have large impacts on ecosystem structure and function. High winds and precipitation associated with storms can affect lakes via short‐term runoff events from watersheds and physical mixing of the water column. In addition, lakes connected to rivers and streams will also experience flushing due to high flow rates. Although we have a well‐developed understanding of how wind and precipitation events can alter lake physical processes and some aspects of biogeochemical cycling, our mechanistic understanding of the emergent responses of phytoplankton communities is poor. Here we provide a comprehensive synthesis that identifies how storms interact with lake and watershed attributes and their antecedent conditions to generate changes in lake physical and chemical environments. Such changes can restructure phytoplankton communities and their dynamics, as well as result in altered ecological function (e.g., carbon, nutrient and energy cycling) in the short‐ and long‐term. We summarize the current understanding of storm‐induced phytoplankton dynamics, identify knowledge gaps with a systematic review of the literature, and suggest future research directions across a gradient of lake types and environmental conditions. [ABSTRACT FROM AUTHOR]

A novel disturbance observer-based backstepping controller (DOBBC) is developed and applied to the path-following system of a container ship. Our control objective is to enable the ships to follow a desired path despite the presence of environmental disturbances caused by current, wind, and wave actions. It is particularly challenging to achieve such an objective due to the underactuation and nonlinearity of container ships. To simplify controller design, a tracking error model is developed based on Serret–Frenet frame transformation. The proposed path-following control system is constructed on the model. In DOBBC, the disturbance observer estimates both constant and time-variant environmental disturbances. The backstepping controller compensates the nonlinearity and underactuation of the container ship. A feedback-dominance technique is utilized to design the controller parameters. The stability and robustness of the control system are successfully justified through Lyapunov approach. Simulation results demonstrate that the DOBBC effectively drives the ship to follow a desired trajectory in spite of the existence of time-varying environmental disturbances. [ABSTRACT FROM AUTHOR]

Environmental disturbances affect ecosystem functioning through changes in organisms' metabolism (direct effect) and biodiversity loss (indirect or biodiversity‐mediated effect). It is still a challenge to separate direct and biodiversity‐mediated effects of environmental changes on ecosystem functioning due to the difficulties in isolating 'true' biodiversity loss effects. Furthermore, it is still unclear whether biodiversity‐mediated effects are as important as direct effects. In this study, we performed an experiment in artificial microcosms to disentangle biodiversity‐mediated and direct effects of two major environmental disturbances on the functioning of aquatic ecosystems: increases in temperature and salinity. The ecosystem function analyzed was the microalgae predation by the zooplankton community (zooplankton grazing rates). Temperature and salinity increases affected the zooplankton grazing rates due to changes in community composition and abundance, as well as organism performance. The impact of salinity changes on community structure was higher than that of temperature; however, the importance of biodiversity‐mediated and direct effects was similar to regulating the ecosystem functioning, albeit they have presented different directions and magnitude across the treatments. At a moderate level of temperature increase, we observed that the biodiversity‐mediated effect was more relevant than the direct effect, with negative effects on the overall grazing rates. Our results suggest that disturbances can affect the functioning of aquatic environments through a set of complex biological mechanisms that balance direct and biodiversity‐mediated effects. We concluded that the relative importance of biodiversity‐mediated effects depends on the type and intensity of the disturbance. [ABSTRACT FROM AUTHOR]

Since the 1990s, despite the existence of measures to protect the quality of water, in Europe as well as in France, water pollution persists. Agriculture is one of the activities that affect its quality. Thus, despite the existence of policies encouraging the reduction of the use of pesticides and fertilizers, contaminations remain. The gap between the both ancient and weighty legal system and the fact that pressures still impact the water resource incites us to take a closer look: protecting water quality must be included in broader sustainability issues. To this end, we integrate agricultural activity in the overall framework of Food Systems, in particular the processes of resilience put in place in answer to environmental disturbances. Such an approach allows us in the first place to question the temporalities of the processes involved - ecological, political, changes in individual and collective practices - which contribute to the environmental dynamics of Food Systems. More broadly, our results enable us to reconsider the environmental sustainability of these systems.

In February and March 2017, a coastal El Niño caused extraordinary heavy rains and a rise in water temperatures along the coast of northern Peru. In this work, we document the impacts of this phenomenon on the artisanal fisheries and the scallop aquaculture sector, both of which represent important socio-economic activities for the province of Sechura. Despite the perceived absence of effective disaster management and rehabilitation policies, resource users opted for a wide range of different adaptation strategies and are currently striving towards recovery. One year after the event, the artisanal fisheries fleet has returned to operating almost on a normal scale, while the aquaculture sector is still drastically impacted, with many people continuing to work in different economic sectors and even in other regions of the country. Recovery of the social-ecological system of Sechura likely depends on the occurrence of scallop seed and the financial capacity of small-scale producers to reinitiate scallop cultures. Long-term consequences of this coastal El Niño are yet to be studied, though the need to develop trans-local and trans-sectoral management strategies for coping with disturbance events of this scale is emphasized. [ABSTRACT FROM AUTHOR]

Agroecosystems suffer various ecological risks due to the intensive production of crops. However, comprehensive assessments of cropland ecological risks remain limited. This study developed an assessment method for cropland ecological risks by combining environmental disturbance with ecosystem vulnerability. Environmental disturbance reflects stresses caused by risk sources in an environment, while ecosystem vulnerability is the susceptibility of an ecosystem to adverse disturbances and its capacity to cope and adapt. The proposed method is conducive to understanding the complex exposure–response relationship between croplands and environmental stresses. Cropland ecological risk was evaluated by conducting a case study on a loess dryland region in Shaanxi. The hot spots and driving factors of risk were explored using spatial autocorrelation and quantile regression methods, respectively. Results show that overall cropland ecological risk is at medium low level. Risk hot spots are concentrated in the north of the loess dryland. Ecosystem vulnerability exerts greater effect on the distribution of hot spots than environmental disturbance in the study area. Road density (RDD), river density, and soil organic matter exert the most important effects on cropland ecological risk. Moreover, the same driving factor exhibits various effects on cropland ecological risk in different risk level areas. RDD, slope, precipitation, elevation, fertilizer application rate, gross domestic product, and distance to town center have greater effects on risk in regions with high cropland ecological risk than in regions with low cropland ecological risk. The findings of this study must be considered in formulating targeted policies for controlling cropland ecological risk in loess drylands to realize sustainable crop production. • A comprehensive methodology for assessing cropland ecological risk is proposed. • Ecosystem vulnerability has dominant effects on the distribution of risk hot spots. • Road density, river density, and soil organic matter are the major drivers on risk. • The effect of each driver on cropland ecological risk varies with risk level. [ABSTRACT FROM AUTHOR]

Sustainable aquaculture needs to be considered when it comes to the utilization of water resources. The aim of this study was to apply biomonitoring using macrobenthic structures on both spatial and temporal applications of monoculture and integrated multi-trophic aquaculture (IMTA) at Tembelas Island, Kepulauan Riau Province, Indonesia. Samples of sediment were taken from three fish farm locations, namely from an IMTA site, a monoculture site, and a reference site. Macrobenthic organisms obtained through rinsing, sieving, and sorting were then identified under a stereo-microscope. Diversity of the macrobenthic assemblages was analyzed with a Shannon-Wiener index (H’). Equitability was expressed through Pielou’s evenness index. Finally, Bray-Curtis’ non-metric multi-dimensional scaling (NMDS) was used for similarities derived from log (X+1) transformed macrobenthic abundance to provide a visual representation of differences in their structure between sites over time. Results showed polychaetes exhibited differences in both variation and abundance of genera between the farm and reference site. The assemblage of macrobenthos at the IMTA site consisted of 9 genera of gastropods, 3 genera of bivalves, 5 genera of polychaetes, and 2 genera of crustaceans. At the monoculture site, 12 genera of gastropods, 4 genera of bivalves, 8 genera of polychaetes, 1 genera of crustaceans, and 1 genera of ophiuroid were observed. A relatively high abundance was observed at the reference site, with 27 genera of gastropods, 11 genera of bivalves, 3 genera of polychaetes, and 1 genera of crustacean. The favorable water conditions and possible absence of waste input from aquaculture resulting in a more suitable habitat for macrobenthic life may explain this relative abundance. Some of them were recognised as opportunistic taxa, i.e., Capitella sp., Heteromastus sp., and Lumbrinereis sp. Based on the diversity and evenness indices and the MNDS ordination, it can be concluded that the application of IMTA systems results in a suppressed or reduced potential impact on environmental disturbance due to aquacultural activities.