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Naturalistic plantings, such as meadow‐style plantings, can improve the quality of urban green spaces through aesthetic, biodiversity and low maintenance features. Species selection for, and maintenance of naturalistic plantings are key to their success. While herbaceous and grassy meadows can be mowed, naturalistic plantings with woody plants require more intense maintenance to remove biomass and promote resprouting. We aim to understand woody plant responses to diverse disturbance regimes to potentially inform the selection and management of woody species in urban plantings. We conducted a quantitative systematic literature review of 72 papers and investigated what main external (climate, disturbance regime) and internal (buds, life stage, storage reserves) factors influence the resprouting response of woody plants. We found resprouting literature is geographically widespread for woody plants, but studies are skewed towards Temperate climates in USA and Australia, with a focus on high severity and high frequency fire disturbance. Resprouting response was mostly defined as a continuous response to disturbance dependent on disturbance regime, climate and plant traits. Maintenance and management of naturalistic woody plantings, through hard pruning techniques such as coppicing, may be informed by analogous high severity and high frequency disturbance studies. However, the literature on woody plant resprouting has several knowledge gaps for lower severity and lower frequency disturbance regimes and in more arid climates. Future research should evaluate the response of naturalistic woody plantings to disturbance in specific urban contexts. [ABSTRACT FROM AUTHOR]

This paper investigates the problem of speed cruise control in high-speed trains, which are modeled as large-scale systems with each car considered as an independent subsystem. Decoupled H ∞ controllers are employed for each car. To address parameter uncertainties and time-varying delays, a comprehensive analysis of the robustness and time-delay stability of the large-scale system was conducted, which led to the design of decoupled controllers. Simulations and comparative analyses were conducted to validate the correctness of the control algorithm and demonstrate the feasibility of controlling high-speed trains as large-scale time-delay systems. This study has yielded theoretical results in large-scale system control, successfully applying results to high-speed train control. The idea and method offer new perspectives and lay the foundation for addressing more complex issues in high-speed trains. [ABSTRACT FROM AUTHOR]

Accurately predicting train running times (TRTs) during disturbances is crucial for effective timetable rescheduling. Previous studies on train running prediction have overlooked the detailed textual description of disturbance events. To improve the prediction accuracy, this paper proposes a hybrid neural network model consisting of a transformer encoder and a fully connected neural network (FCNN) to predict the TRTs under disturbances, which is called transformer-FCNN here. In the proposed transformer-FCNN architecture, a transformer encoder is used to process textual disturbance events, while FCNN is used to deal with static features. The performance of transformer-FCNN is validated using data from the Wuhan-Guangzhou and Xiamen-Shenzhen high-speed railways. The results show that the models considering the disturbance category can substantially improve the predictive performance compared with those that do not. Further, based on the same algorithm, models which use textual disturbance event records are shown to reduce the mean absolute error and the root mean squared error, respectively, by over 10.8% and 8.3% on average compared with those that only consider the disturbance category. The proposed model can support potential strategies of train operation control, by providing accurate prediction results. [ABSTRACT FROM AUTHOR]

In a nonlinear control system, hysteresis exists usually as common characteristics. In addition, external output disturbances like modelling error, machine friction and so on also occur frequently. Both of them are considered to cause instability and unsatisfactory performance. In this paper, a practical nonlinear control system design is proposed so as to achieve the simultaneous control of input hysteresis and output disturbance. The system is based on RCF (right coprime factorization theory). Additionally, the proposed design has been applied to a soft robotic finger system and the results of simulations and practical experiments are exhibited, which show the effectiveness of the proposed system. [ABSTRACT FROM AUTHOR]

In the Anthropocene, intensifying ecological disturbances pose significant challenges to our predictive capabilities for ecosystem responses. Macroecology—which focuses on emergent statistical patterns in ecological systems—unveils consistent regularities in the organization of biodiversity and ecosystems. These regularities appear in terms of abundance, body size, geographical range, species interaction networks, or the flux of matter and energy. This paper argues for moving beyond qualitative resilience metaphors, such as the 'ball and cup', towards a more quantitative macroecological framework. We suggest a conceptual and theoretical basis for ecological resilience that integrates macroecology with a stochastic diffusion approximation constrained by principles of biological symmetry. This approach provides an alternative novel framework for studying ecological resilience in the Anthropocene. We demonstrate how our framework can effectively quantify the impacts of major disturbances and their extensive ecological ramifications. We further show how biological scaling insights can help quantify the consequences of major disturbances, emphasizing their cascading ecological impacts. The nature of these impacts prompts a re-evaluation of our understanding of resilience. Emphasis on regularities of ecological assemblages can help illuminate resilience dynamics and offer a novel basis to predict and manage the impacts of disturbance in the Anthropocene more efficiently. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'. [ABSTRACT FROM AUTHOR]

Since the integration of electronic devices and intelligent electronic devices into the power grid, power quality (PQ) has consistently remained a significant concern for system operators and experts. Maintaining high standards of power quality is crucial to preventing malfunctions and faults in electric assets and connected loads. Recently, PQ studies have shifted their focus to a specific frequency range, previously not considered problematic—the supraharmonic 2 kHz to 150 kHz range. This range is not populated by easily recognizable harmonic components of the 50 Hz to 60 Hz mains fundamental, but by a combination of intentional emissions, switching non-linearities and byproducts, and various types of resonances. This paper aims to provide a detailed analysis of the impact of supraharmonics (SHs) on power network operation and assets, focusing on the most relevant documented negative effects, namely power loss and the heating of grid elements, aging of dielectric materials, failure of medium voltage (MV) cable terminations, and interference with equipment and power line communication (PLC) technology in particular. Under some shareable assumptions, limits are derived and compared to existing ones for harmonic phenomena, providing a clear identification of the primary issues associated with supraharmonics and suggestions for the standardization process. Strictly related is the problem of grid monitoring and assessment of SH distortion, discussing the suitability of normative requirements for instrument transformers (ITs) with a specific focus on their accuracy. [ABSTRACT FROM AUTHOR]

The permanent magnet electrodynamic suspension (PMEDS) owns the promising application prospect, due to its simple structure, low cost and reliable load capacity. However, the underdamping of the PMEDS system is still a challenge in engineering applications of transportation. This paper proposes a passive damping method and its implementation structure to improve the underdamping characteristics. This method utilizes the inherent magnetic leakage of on-board magnets technically. The principle of passive damping and its implementation structure is introduced in detail. And the kinetic models of ordinary and improved structure are established based on the topology graph. Besides, the magnetic field and the electromagnetic force involved in the kinetic models are analyzed, and the numerical analysis method of the drag force is verified by the high-speed test rig. Furthermore, the performance of passive damping is verified by finite element method (FEM) and the time-domain response analysis. The results show that the improved damping structure can effectively suppress vibration and improve the dynamic stability of the PMEDS system. It is beneficial to the engineering application of the PMEDS in the future. [ABSTRACT FROM AUTHOR]

As coral reefs endure increasing levels of disturbance, understanding recovery patterns of reef‐building hard corals is paramount to assessing the sustainability of these ecosystems. At local scales, coral recovery slows down; however, it's unclear how this trend propagates across spatial scales due to the inherent complexity of coral dynamics. In this paper, we aimed to learn about fine scale heterogeneity of coral dynamics and explore implications for assessing coral recovery at larger spatial scales. We developed a spatio‐temporal statistical model to estimate long‐term trajectories of three types of corals and predict their recovery patterns at unobserved locations within a reef. Then, model predictions were used to derive metrics that capture the interplay between coral growth and decline from disturbance(s) across time, space and growth morphology. This model is developed in the context of a substantive case study at Heron Reef using a high spatio‐temporal resolution dataset. Our results revealed that successful coral community recoveries took place in different habitats of Heron Reef and associated with various reasons. Branching corals recovered in the southern slope, due to fast growth in locations that were previously abundant. Plate corals flourished in the northern slope due to fast growth, despite a large decline and low baseline cover. They also recovered in the southern slope but in this case there was both a low decline and baseline cover. At Heron Reef, the recovery of coral communities followed specific conditions that were acting at a fine scale in a complex and heterogeneous way within habitat. This implies that capturing the variability of fine‐scale coral dynamics is an important first step to detect accurate signals of coral recovery at larger spatial scales. The approach proposes here can be further extend to the scale of a reef and beyond enabling assessment of recovery patterns representative at management scales. [ABSTRACT FROM AUTHOR]

This paper is concerned with the attitude tracking problem of quadrotor unmanned aerial vehicles (UAVs) with respect to endogenous uncertainties, exogenous disturbances and actuator failures. Two different control methods are proposed to solve this problem. First, an adaptive extended state observer (AESO)-based control framework is devised to tackle the difficulties caused by model uncertainties and external disturbances. A fault-tolerant control method is proposed to cope with the occurrence of actuator failure, which is modeled as a constant loss of effectiveness. Another method employs AESOs to compensate for lumped disturbances, which include endogenous uncertainties, exogenous disturbances and actuator failures. Then, the error can exponentially converge to a bounded set. Finally, simulations are performed to ensure the feasibility of the designed technique. [ABSTRACT FROM AUTHOR]

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Disturbances caused as a result of the misalignment and axial motion of the journal affect the characteristics of the rotor-bearing system. This paper aims to propose an algorithm for the theoretical analysis of a rotor-bearing system that considers these disturbances. A theoretical model for a journal bearing considering disturbances is given. The dynamic equations for a rigid rotor-bearing system are introduced. A detailed algorithm that can simultaneously solve the rotor-dynamic equations and the Reynolds equation is proposed. The static performance, such as the bearing attitude angle and the fluid film pressure, are given, and dynamic characteristics such as the nonlinear dynamic responses and the axial orbits of a rigid rotor-bearing system are presented. The hydrodynamic effect of the bearing is enhanced by the axial disturbance. Disturbances in the circumferential and radial directions lead to variations in the fluid film thickness distribution in the axial direction and the offset of the fluid film pressure distribution in the axial direction. When these disturbances work together, the variation trend is more obvious and affects the capacity and dynamic characteristics of the bearing. When the L/D value of the bearing increases, the clearance between the journal and the bearing decreases rapidly. When the value reaches a certain limit, contact and collision might occur. The theoretical analysis method and the algorithm proposed for a rotor-bearing system considering several disturbances could enhance the design level for a bearing and rotor-bearing system. [ABSTRACT FROM AUTHOR]

Globally, protected areas such as national parks are mainly established to protect the rapidly declining populations of conservation concern wildlife species, as well as ecologically and economically important areas. In addition, more recently, establishing and maintaining protected areas has become an essential part of the global response of governments to combat climate change and its impacts. However, most of these protected areas are facing an unprecedented rate of biodiversity and ecosystem degradation due to human-induced actions. Mitigation of threats and their impacts on biodiversity in these protected areas is very critical. But limited information, needed to develop strategies for mitigation of the ever-growing threats, is available on the biophysical resources and threats to them. This paper presents for the first time, detailed information on the Exceptional Resource Values (ERVs), Principal Ecosystem Components (PECs; or conservation targets), and human-induced threats in the Kafta-Sheraro National Park (KSNP). Standard ecological and social science methods were used to collect and analyze the data. Overall, 14 key ERVs were identified in the park, including several conservation concerns and/or flagship mammal species (e.g. African Elephant (Loxodonta africana)), biome-restricted and migratory bird species (e.g., Demoiselle crane (Anthropoides virgo)), three distinct habitat types, and a hydrological system. Six PECs that were assumed to represent the whole ecosystem components of the park were identified in KSNP: the three habitat types, hydrological system, Elephant, and Roan antelope (Hippotragus equines). The top human-induced threats to these PECs appeared to be fire, cultivation, grazing, settlement, poaching, and mining. In general, KSNP contains outstanding biodiversity and other natural resources that could play a vital role in the socio-economic development of local and regional communities. To ensure the long-term persistence of the ERVs and PECs and the appropriate functioning of the park ecosystems the development and implementation of threat mitigation strategies are required. [ABSTRACT FROM AUTHOR]

Human‐caused global change produces biotic and abiotic conditions that increase the uncertainty and risk of failure of restoration efforts. A focus of managing for resiliency, that is, the ability of the system to respond to disturbance, has the potential to reduce this uncertainty and risk. However, identifying what drives resiliency might depend on how one measures it. An example of a system where identifying how the drivers of different aspects of resiliency can inform restoration under climate change is the northern coast of California, where kelp experienced a decline in coverage of over 95% due to the combination of an intense marine heat wave and the functional extinction of the primary predator of the kelp‐grazing purple sea urchin, the sunflower sea star. Although restoration efforts focused on urchin removal and kelp reintroduction in this system are ongoing, the question of how to increase the resiliency of this system to future marine heat waves remains open. In this paper, we introduce a dynamical model that describes a tritrophic food chain of kelp, purple urchins, and a purple urchin predator such as the sunflower sea star. We run a global sensitivity analysis of three different resiliency metrics (recovery likelihood, recovery rate, and resistance to disturbance) of the kelp forest to identify their ecological drivers. We find that each metric depends the most on a unique set of drivers: Recovery likelihood depends the most on live and drift kelp production, recovery rate depends the most on urchin production and feedbacks that determine urchin grazing on live kelp, and resistance depends the most on feedbacks that determine predator consumption of urchins. Therefore, an understanding of the potential role of predator reintroduction or recovery in kelp systems relies on a comprehensive approach to measuring resiliency. [ABSTRACT FROM AUTHOR]

Agroforestry is a widely proposed solution for climate change adaptation and resilience in agriculture due to the multiplicity of socio-ecological benefits. However, agroforestry as a practice exists on a dynamic scale of ecological complexity, which may cause different management regimes to respond distinctively to climate change. Due to the limited literature on climate change impacts on agroforestry in the temperate region, this paper reviews disturbance regimes and the observed and predicted responses of forests and farms using the US Northeast as an example. We also reference scholarship from tropical regions, where agroforestry adoption/study is more advanced, to enhance understanding of the growing field of agroforestry in temperate systems. We view transitions to and from agroforestry from a complex systems lens by identifying the disturbance, complexity, resilience, and adaptive capacity of systems to drive and respond to rapid change via human management, focusing on invasive species, phenological changes and range shifts in plants, pests, and pathogens of agroforestry systems. Management considerations including structural diversity, species selection and the intentional/non-intentional incorporation of introduced species can promote community ecological resilience to build systems that have adaptive capacity to withstand changing conditions. [ABSTRACT FROM AUTHOR]

This paper devotes to the design of all feasible output feedback controllers for the robust output tracking of Boolean control networks with disturbances (DBCNs). First, the output feedback–based robust control invariant set (RCIS) is defined, and a calculation method to find all output feedback–based RCISs of a given set is derived via the truth matrix technique. Second, a class of complete family of robust reachable sets (CFRRSs) is developed; the solvability of robust output tracking problem by output feedback control is verified. Furthermore, a constructive algorithm of all feasible output feedback controllers is presented. Finally, the study of a network about Escherichia coli lactose operon shows the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

This paper presents a novel leader-follower consensus control for a particular class of nonlinear multi-agent mechanical systems in the presence of control input constraints and external disturbances which includes robot system dynamics with a wide range of potential applications in industry. In this case, one of the agents is selected as the leader to direct the other agents in such a way that the whole system can reach consensus within certain prescribed performance transient bounds. Due to the presence of disturbances in most practical systems, the effect of limited disturbance in the consensus control method has been investigated, and actuator saturation is included in the design process. A terminal sliding mode control method has been adapted to ensure the stability of the overall system and fast finite-time leader-follower consensus control. The simulation results of the multi-agent nonlinear robot system in MATLAB environment, in different scenarios with simultaneous consideration of actuator saturation and external disturbance, will show the efficiency of the proposed control method. [ABSTRACT FROM AUTHOR]

In this paper, a LuGre model–based robust adaptive control (RAC) approach is presented for a pump-controlled hydraulic actuator. We first decompose the LuGre friction model into its steady-state model and a lumped dynamic part applying the mean value theorem, which are compensated by a feedforward term and a robust adaptive term, respectively. The robust adaptive term also plays a part in mismatched disturbance attenuation. In addition, parametric uncertainties and matched disturbances are handled by σ -modified adaptation laws and a robust control law, respectively. The stability of the closed-loop system is proved via the Lyapunov analysis. The efficacy and robustness of the proposed approach are validated by comparative experiments. Compared with common adaptive friction compensation methods, the proposed method has a simpler structure, less computational burden, better control performance, and stronger robustness. Moreover, since the available information is separated from the LuGre model and acts as a model-based compensation term, the design conservativeness of RAC is effectively reduced. [ABSTRACT FROM AUTHOR]

The thermospheric density and its variations are crucial to aerospace activities as well as space weather research and operation. However, due to the difficulties in observing the thermosphere, there has been a lack of effective descriptions for the general characteristics of thermospheric density. In this paper, the Two‐Line‐Element data sets (TLEs) from multi‐target low Earth orbit satellites are used to derive a proxy of the daily average atmospheric density in the thermospheric shell located in the vicinity of LEOs' orbital altitude. It captures the overall characteristics of the thermosphere and exhibits good correlations (∼0.9) with modeled and observed thermospheric density. By applying the spectral whitening method to this proxy, a new index JsT ${J}_{s}^{T}$ is derived to describe non‐periodic perturbation of the density where the specific satellite passed by. The fact that the JsT ${J}_{s}^{T}$ obtained from different satellites within the same thermospheric shell presents significant consistency to each other means that the new index is a good indicator for the overall feature of the variations of thermospheric density, and it is possible to define a unified regional index JrT ${J}_{r}^{T}$ to describe density disturbances for the thermospheric shell where these satellites fly through. Moreover, the JrT ${J}_{r}^{T}$ at different altitudes also present good consistency suggesting the possibility of defining a global index JpT ${J}_{p}^{T}$, capable of describing the density variation of the entire thermosphere. Plain Language Summary: Due to limited in situ observation, the thermospheric density is not easy to obtain. Herein, we have extracted the density information of the thermosphere based on the Two‐Line‐Element data sets and developed a new index using the spectral whitening method, which describes aperiodic disturbances of the density. The construction of this index series can address the limitations of existing quantitative or graded descriptions of space weather disturbances and the problem of mismatched or inconsistent parameters/indices. Ultimately, this will contribute to the monitoring and warning of space weather causal chains. Key Points: A proxy of daily average thermospheric mass density was extracted from Two‐Line‐Element data setsBy applying the spectral whitening method to this proxy, a new index is derived to describe non‐periodic perturbations in the thermosphereA unified regional index was defined to describe density disturbances for the thermospheric shell where these satellites fly through [ABSTRACT FROM AUTHOR]

Summary: This paper investigates the tracking control problem of connected vehicle system suffer from disturbance and communication load. A new dynamic triggered‐based tracking approach was presented. First, an extended state observer is designed to estimate the equivalent disturbance, and the convergence of observed error is proved. Then, a tracking approach based on backstepping control is proposed. Furthermore, in order to reduce the consumption of network resources, a novel tracking method on dynamic event‐triggering strategy is developed, and all signals in connected vehicle system are ultimately uniformly bounded without Zeno behavior is verified. Finally, the effectiveness of the proposed control strategy is testified by simulation results. [ABSTRACT FROM AUTHOR]

The floodplains of the Southeast's stream network once hosted immense brakes of rivercane (Arundinaria gigantea), a disturbance-dependent native bamboo with both cultural and ecological significance. Ecologically, rivercane alters its local environments, boosts biodiversity and biomass, and protects streambanks from erosion and storm damage. Indigenous peoples of the Southeast have used rivercane for millennia, for material and cultural purposes, and formerly maintained its health and extent through harvesting and fire. Settler-colonial incursions largely destroyed rivercane, through the more intense disturbance of different land management practices, and brakes now exist mainly in relatively small areas. While numerous rivercane restoration projects are in process throughout its natural range, no comprehensive inventory of living rivercane exists. In this paper, we present both human context and the results of LiDAR analysis that identifies canebrakes based on the physical characteristics of the plant and brake. In our study area on the Little Tennessee River in western North Carolina, we found rivercane on about 9 percent of the floodplain area, based on QL1 LiDAR data available from the state of North Carolina. The technique can be applied in any part of rivercane's range, and the resulting inventory used in support of both cultural and ecological goals. [ABSTRACT FROM AUTHOR]

This paper proposes a neural network-based robust model predictive control (MPC) strategy for visual serving of autonomous vehicles (AVs) with uncertain payloads, ground friction disturbances, and air resistance effects. Based on the dynamics of visual servoing errors and driving of the AV, the quasi-min–max MPC is adopted to calculate the desired velocity of the AV subject to the constraints on the speed, control, and the visual field. The backpropagation (BP) neural network is then used to learn the ground friction disturbances of the AV, which is adopted to compensate the quasi-min–max MPC of the visual servoing system. Finally, the performance of the proposed controller is evaluated and verified by some comparison simulations. [ABSTRACT FROM AUTHOR]

Temperate woodland vegetation is initially determined by spatiotemporal and historical factors, mediated by complex biotic interactions. However, catastrophic events such as disease outbreaks (e.g., sweet chestnut blight, ash dieback), infestations of insect pests, and human-accelerated climate change can create canopy gaps due to systematic decline in, or loss of, tree species that was once an important part of the canopy. Resultant cascade effects have the potential to alter the composition of woodland ecosystems quickly and radically, but inherent lag times make primary research into these effects challenging. Here, we explore change in woodland vegetation at 10 sites in response to canopy opening using the Elm Decline, a rapid loss of Ulmus in woodlands across northwestern Europe ~ 5800 years ago that coexisted alongside other stressors such as increasing human activity, as a palaeoecological analogue. For arboreal taxa, community evenness significantly decreased, within-site turnover significantly increased, and richness remained unchanged. Changes in arboreal taxa were highly site-specific but there was a substantial decline in woody climbing taxa, especially Hedera (ivy), across the majority of sites. For shrub taxa, richness significantly increased but evenness and turnover remained consistent. Interestingly, however, there was a significant increase in abundance of shrubs at 70% of sites, including Calluna (heather), Ilex (holly) and Corylus (hazel), suggesting structural change. Surprisingly, there was no change in richness, evenness or turnover for herb taxa, possibly because change was highly variable spatially. However, there was a marked uptick in the disturbance indicator Plantago (plantain). Overall, these findings suggest that woodlands with sustained reduction in, or loss of, a tree species that once formed an important part of the canopy has profound, but often spatially idiosyncratic, impacts on vegetation diversity (richness), composition (evenness), stability (turnover), and on abundance of specific taxa, especially within the shrub layer. Use of this palaeoecological analogue, which was itself complicated by cooccurring changes in human activity, provides a valuable empirical insight into possible cascade effects of similar change in canopy opening in contemporary settings, including Ash Dieback. [ABSTRACT FROM AUTHOR]

The occurrence of droughts in recent decades has prompted researchers to pay closer attention to soil shrinkage. It is no longer appropriate to assume that surface soils in temperate countries are always saturated. When using traditional geotechnical identifications for soil classification based on swelling and shrinkage, the soil density is not consistently considered as a crucial parameter, nor is the state of the soil (intact or disturbed) or the degree of soil cementation. This article highlights the importance of studying the soil in its intact state to accurately represent its behavior on-site. The microstructure of undisturbed soil differs from that of disturbed soil and governs its macroscopic behavior. The method and level of soil disturbance have an impact on the results, depending on whether the focus is on shrinkage or swelling behavior and cementation. This research demonstrates that disturbed samples of clayey soils (Romainville green clay) exhibit lower shrinkage amplitude than intact clayey soil samples, whereas disturbed marly soil samples (Argenteuil blue marl) show the opposite trend. Furthermore, depending on the disturbance method, the swelling amplitude of intact soil samples may be higher or lower than that of disturbed soil samples. The results indicate that conducting a swelling test on W-disturbed samples and a shrinkage test on C-disturbed samples allows us to assess more closely the behavior of intact soil samples. In conclusion, recommendations for a more accurate assessment of the swelling-shrinkage potential of any given soil are provided, considering the test method and the level of disturbance of the sample. [ABSTRACT FROM AUTHOR]

We aimed to analyze the natural population characteristics and habitat growth conditions of the valuable seaweed Silvetia siliquosa. Its population characteristics and habitat conditions were assessed monthly from May 2022 to April 2023 and April to August 2022, respectively, on selected habitats. The average population density, coverage, and frequency of S. siliquosa were 579 ± 94.18 ind./m2, 27.82 ± 6.92%/m2, and 78.37 ± 5.98/m2, respectively. The average thallus length and width were 47.53 ± 4.35 and 46.33 ± 4.17 mm, respectively, while the branch width, thickness, and frequency were 2.35 ± 0.03 mm, 0.59 ± 0.12 mm, and 2.8 ± 0.2 times, with a receptacle length and width of 24.13 ± 2.07 and 2.81 ± 0.19 mm, respectively. Among the 40 previously known natural habitats of S. siliquosa, growth was confirmed only in Sepo, Sebang, and Bangpo. The causes for the declining S. siliquosa populations could be attributed to habitat changes due to construction, coastal road maintenance projects, habitat disturbances, and increased pollutants. Habitat substrate disturbances and changes were the main causes of the decrease in S. siliquosa growth. Studies on environmental factors and habitat degradation, growth related to environmental factors, mass cultivation, and the marine ecosystem restoration of S. siliquosa are needed. [ABSTRACT FROM AUTHOR]

We selected 15 sheep‐grazed sand pastures along a gradient of increasing grazing intensity to study the fine‐scale patterns of main biomass fractions (green biomass, litter) and that of plant species and functional groups (life forms and social behaviour types). We classified them into five grazing intensity levels based on stocking density, proximity to drinking and resting places and the number of faeces. We aimed to answer the following questions: (i) How does increasing intensity of sheep grazing affect the amount of green biomass, the species richness and their relationship in sand pastures? (ii) How does increasing intensity of sheep grazing affect the biomass of perennial and short‐lived graminoids and forbs? (iii) How does the disturbance value—expressed in the biomass ratio of disturbance‐tolerant and ruderal species—change along the gradient of grazing intensity? A unimodal relationship between green biomass and species richness was detected; however, the ordination (canonical correspondence analysis, CCA) showed no clustering of pastures subjected to the same levels of grazing intensity. Along the grazing intensity gradient we found an increasing trend in species richness and significant differences in green biomass (decreasing trend), litter (decreasing trend), graminoids (decreasing trend) and short‐lived forbs (increasing trend). We found an increasing amount of disturbance‐tolerant and ruderal species with increasing grazing intensity. We suggest that we might need to use multiple scales for sampling and a fine‐scale assessment of grazing intensity. Our findings might be instructive for pastures in densely populated regions, which are prone to the encroachment of disturbance‐tolerant and ruderal species. [ABSTRACT FROM AUTHOR]

Robust regulation is predictively investigated in time-delay models including uncertainties, non-zero reference, and disturbance. Hence, to handle the complexities induced because of the time-delays, disturbances, and uncertainties, enhancing the transient performance would be a main control goal. To this purpose, the required transient and steady-state specifications are achieved through an integral control structure with adjustable gains. The constraints on the signals and aims of the control algorithm are also described by some linear matrix inequalities. Guaranteeing the stability, a minimisation procedure is found to specify the predictive controller. Several simulations are performed to establish the effectiveness of the introduced plan in comparison with the similar strategy. [ABSTRACT FROM AUTHOR]

By incubating the soil without living roots in situ at two spruce forest sites, we simulated the effects of tree dieback and interrupted mycorrhizal associations following forest disturbance on the soil microbiome and phosphorus leaching. We observed the retreat of ectomycorrhizal fungi and increased proportion of saprotrophs without changes in community richness and the Shannon diversity index. This was accompanied by a pronounced decomposition of organic matter, associated with an increased activity of carbon-mining hydrolases and acid phosphatase. The nonexistent phosphorus uptake and immobilization by ectomycorrhizal associations led to its substantial increase in the soil, in the labile fractions, such as microbial biomass and water-soluble reactive phosphorus, but also in the fraction bound to organometallics (extractable by oxalate), and caused considerable phosphate leaching, as estimated using ion-exchange resin traps. The results show that the retreat of the root-specific environment, characterized by the input of available carbon and effective nutrient uptake and by the specific microbiome, has profound effects on phosphorus dynamics and loss. Furthermore, we suggest that ectomycorrhiza plays an equally important role in controlling phosphorus-mining from organic matter and subsequent immobilization and/or leaching from soils concurrently to its known role in nitrogen cycling and immobilization in spruce forests. [ABSTRACT FROM AUTHOR]

The objective of the invariant ellipsoid method is to minimize the smallest invariant and attractive set of a linear control system operating under the influence of bounded external disturbances. This study extends the application of this method to address the leader-following consensus problem. Initially, a linear control protocol is designed for the multi-agent system in the absence of disturbances. Subsequently, in the presence of bounded disturbances, by employing a similar linear control protocol, a necessary and sufficient condition is introduced to derive the optimal control parameters for the multi-agent system such that the state of followers converges to and remains in a minimal invariant ellipsoid around the state of the leader. [ABSTRACT FROM AUTHOR]

The forests of the Western Ghats (WG) of India are a highly diverse ecosystem though altered over time by human interference. The Northern Western Ghats (NWG) differ in bioclimatic and geological characteristics from the rest of the Western Ghats, featuring a mix of forested and open landscapes. Human activities such as shifting cultivation, cutting, lopping, periodic fire, constructions (road and dam), and mining have further increased their fragmentation, leading to a decrease in biodiversity. While the region has been extensively investigated for its floristic diversity, quantitative ecological studies are limited. This review seeks to identify research gaps and new research directions in the forest ecology of the NWG by compiling various periodical studies carried out in the region. It covers various works on vegetation types, species diversity and composition, and forest degradation due to anthropogenic activities. We provide compiled comparative vegetation types applicable to the region. The present review also discusses works carried out on forest areas under various protection regimes, such as legally protected areas, sacred groves, and private forests, using quantitative and remote sensing tools. We believe that understanding the NWG as an entire unit using uniform methods is essential, and this review serves as an important step in achieving this. It provides a comprehensive overview of the NWG, which can be used to plan out future research in this region. [ABSTRACT FROM AUTHOR]