Site Conditions Research Articles

Lack of management, land-use changes, poor site conditions and drought contribute to the decline of old pollarded oaks

In Europe, people have managed forests and woodlands for centuries. Old pollarded oaks reflect historical legacies, and their conservation is threatened by the abandonment of this traditional forest use. However, site conditions (topography, soil features, land cover, and historical use) and warming-triggered drought stress also contribute to their growth decline, particularly in seasonally dry regions. We investigated two stands of pollarded Mediterranean oaks (Quercus subpyrenaica), where pollarding was abandoned in the 1950s, showing contrasting land cover and tree sizes in north-eastern Spain. Changes in land cover, soil characteristics (texture, pH, and nutrient concentrations), climate conditions, and tree-ring data (basal area increment −BAI−, and ring-width indices) were analysed. The Artosilla site, showing the smallest trees, presented the lowest long-term growth rates (period 1730−2022, mean BAI = 19.7 cm2 yr−1) as compared with the Aineto site with bigger oaks (mean BAI = 32.9 cm2 yr−1). Old trees were found in both sites with ages ranging 293−311 years. The less fertile soils in Artosilla, where pine plantations diminish canopy thermal amplitude, may contribute to the long-term growth decline observed there. Moreover, more major growth suppressions were found in this site, particularly in the 1940s, which suggest a more intensive historical use. Aineto showed a stronger BAI decline since the 1950s, which could be a response to increasingly warmer and drier summer conditions. In contrast, growth in Artosilla is decoupling from soil and atmospheric drought suggesting chronic growth stagnation. Poor site conditions (steeper slope, less fertile soils, intensive historical use) contributed to the decline of pollarded oaks. Active management is required to preserve these unique old, monumental trees.

In-depth analysis of critical factors affecting Iraqi construction projects performance

Abstract Construction projects in Iraq suffer from many complex problems. Therefore, the aim of this study is to identify the most critical factors affecting the performance of Iraqi construction projects, delving into their identification, analysis, and understanding. A comprehensive list of 32 influential factors was compiled through site surveys, interviews with engineers and experts, and a review of previous research. These factors were categorized into eight groups: planning and management, design and engineering, procurement and supply chain, workforce and labor, technology and innovation, environmental and regulatory aspects, site conditions and infrastructure, and external factors. One hundred and ten questionnaires were distributed to project stakeholders, including owners, consultants, and contractors. The results found that the five most important factors affecting performance ranked using the relative importance Index are poor planning, failure to allocate resources properly, unavailability of skilled labor, poor labor productivity, and volatile economic conditions. Based on these results, for solutions to be effective, they must be adapted to the local environment. Project participants must be interested in planning as it is essential to address the same. The skills of project workers must be developed through training programs. Communication with project stakeholders must be coordinated to contribute to the decision-making process.

Postharvest evaluations of soil erosion, ground cover, and best management practice implementation on integrated biomass and conventional clearcut harvest sites

As demand for wood energy rises, it’s vital to understand the environmental impact of various harvest types, considering different best management practices (BMPs) and site conditions, for sustainable forest management. This study provides a comparative analysis of postharvest site characteristics between biomass and conventional harvest sites located in the Coastal Plain region of the southeastern US. A total of 30 recently harvest sites (15 each for biomass and conventional) were selected from the Coastal regions of Alabama, Georgia, and Florida. Erosion rates were estimated using the USLE-Forest method and ground cover was assessed as a percentage of the area covered by bare soil, litter, light slash, heavy slash, and piles. BMP implementation (%) was based on state-specific BMP surveys. The findings show that stream management zones (SMZs) and harvest areas were less prone to soil erosion, while forest roads, skid trails, and stream crossings were more prone to erosion, regardless of the harvest type. Conventional harvest sites had an overall weighted average erosion rate of 0.35 Mg/ha/year, with an average BMP implementation of 92.70 %, while biomass harvest sites had an overall weighted average erosion rate of 0.22 Mg/ha/year, with an average BMP implementation rate of 97.91 %. Average erosion rate (Mg/ha/year) from the harvest area (biomass=0.11, conventional=0.06) and SMZs (biomass=0.05, conventional=0.02) were not significantly different (p>0.05). Conversely, average erosion rate from roads (biomass=4.17, conventional=6.44), skid trails (biomass=2.15, conventional=3.73), decks (biomass=0.39, conventional=0.72), and stream crossings (biomass=1.53, conventional=5.31) were significantly higher in conventional harvest sites (p<0.05). BMP implementation rates for roads (biomass=98.09 %, conventional=93.71 %), stream crossings (biomass=95 %, conventional=71 %), and timber harvest (biomass=96.44 %, conventional=93.33 %) were significantly higher in biomass harvest sites, while waste management BMP (biomass=89.91 %, conventional=100 %) was significantly higher in conventional harvest sites. Regarding ground cover, conventional harvest sites had significantly larger areas covered by light slash, heavy slash, and piles than biomass harvest sites, while biomass harvest sites had significantly larger areas covered by green growth. Our research shows a significant negative correlation between overall BMP implementation and erosion rates (r=-0.67, p=0.0002), as well as site size (r=-0.38 p=0.0400), indicating that larger sites tend to have lower BMP implementation and increased erosion risk. In conclusion, biomass harvest sites in our study did not yield higher erosion rates in comparison to conventional harvest sites, provided that the current BMP recommendations were implemented properly and in adequate amounts. This study emphasizes the importance of site-specific management strategies to mitigate erosion in all harvest sites, irrespective of harvest type used.

Leveraging successional facilitation to improve restoration of foundational dune grasses along a frequently disturbed coastline

Coastal ecosystems provide critical storm and flood protection but are rapidly degrading worldwide, making their restoration urgent. We evaluated whether successional facilitation, where pioneers facilitate climax species, could be leveraged to accelerate coastal dune revegetation. A survey spanning 270 km of Southeast U.S. coastline revealed that Panicum amarum (bitter panicum) supported higher plant richness than Uniola paniculata (sea oats) and that sea oat cover was 230% greater on mature dunes than disturbed dunes, suggesting bitter panicum functions as a pioneer and sea oats as a climax species. A reciprocal transplant experiment confirmed this interpretation: bitter panicum stem production and height fell by 37% and &gt;20 cm, respectively, when planted proximate to sea oats versus in isolation, whereas sea oats produced 38% more and &gt;12 cm taller stems when planted proximate to bitter panicum versus in isolation. A second experiment evaluating the density‐dependence of this facilitative interaction revealed that sea oats transplanted into low densities of bitter panicum grew &gt;15% taller than isolated and high‐density treatments. However, within 7 months, wave inundation eliminated over 60% of propagules in both experiments. To explore foredune inundation frequency and its implications for dune revegetation, we applied empirical wave runup models at 101 locations throughout Volusia County, Florida. While disturbance frequency varied seasonally and annually, sites with low dune crests and steep beach slopes experienced frequent inundation (&gt;50 events/year). Given the interactions between geomorphology and vegetation success, we present a decision matrix to guide managers in determining optimal revegetation methods tailored to project goals and site conditions.

Triple-isotope analysis in tree-ring cellulose suggests only moderate effects of tree species mixture on the climate sensitivity of silver fir and Douglas-fir.

Disentangling the factors influencing the climate sensitivity of trees is crucial to understanding the susceptibility of forests to climate change. Reducing tree-to-tree competition and mixing tree species are two strategies often promoted to reduce the drought sensitivity of trees, but it is unclear how effective these measures are in different ecosystems. Here, we studied the growth and physiological responses to climate and severe droughts of silver fir and Douglas-fir growing in pure and mixed conditions at three sites in Switzerland. We used tree-ring width data and carbon (δ13C), oxygen (δ18O) and hydrogen (δ2H) stable isotope ratios from tree-ring cellulose to gain novel information on water relations and the physiology of trees in response to drought and how tree species mixture and competition modulate these responses. We found significant differences in isotope ratios between trees growing in pure and mixed conditions for the two species, although these differences varied between sites, e.g. trees growing in mixed conditions had higher δ13C values and tree-ring width than trees growing in pure conditions for two of the sites. For both species, differences between trees in pure and mixed conditions regarding their sensitivity to temperature, precipitation, climatic water balance and vapor pressure deficit were minor. Furthermore, trees growing in pure and mixed conditions showed similar responses of tree-ring width and isotope ratios to the past severe droughts of 2003, 2015 and 2018. Competition had only a significantly negative effect on δ13C of silver fir, which may suggest a decrease in photosynthesis due to higher competition for light and nutrients. Our study highlights that tree species mixture may have only moderate effects on the radial growth and physiological responses of silver fir and Douglas-fir to climatic conditions and that site condition effects may dominate over mixture effects.

Disproportionality Analysis of Nusinersen in the Food and Drug Administration Adverse Event Reporting System: A Real-World Postmarketing Pharmacovigilance Assessment

BackgroundNusinersen is the first drug for precise targeted therapy of spinal muscular atrophy, a rare disease that occurs in one of 10,000 to 20,000 live births. Therefore, thorough and comprehensive reports on the safety of nusinersen in large, real-world populations are necessary. This study aimed to mine the adverse event (AE) signals related to nusinersen through the Food and Drug Administration Adverse Event Reporting System (FAERS) database. MethodsWe extracted reports of AEs with nusinersen as the primary suspect from FAERS between December 2016 and March 2023. Reporting odds ratio (ROR) and Bayesian confidence propagation neural network (BCPNN) were used for AE signal detection. ResultsWe extracted a total of 4807 suspected AE cases with nusinersen as the primary suspect from the FAERS database. Among them, 106 positive signals were obtained using the ROR and BCPNN. The highest frequency reported systemic organ class was general disorders and administration site conditions. Common clinical AEs of nusinersen were detected in the FAERS database, such as pneumonia, vomiting, back pain, headache, pyrexia, and post–lumbar puncture syndrome. In addition, we identified potential unexpected serious AEs through disproportionality analysis, including sepsis, seizure, epilepsy, brain injury, cardiorespiratory arrest, and cardiac arrest. ConclusionsAnalyzing large amounts of real-world data from the FAERS database, we identified potential new AEs of nusinersen by disproportionate analysis. It is advantageous for health care professionals and pharmacists to concentrate on effectively managing high-risk AEs of nusinersen, improve medication levels in clinical settings, and uphold patient medication safety.

Farmers' preferences for the design of a slurry hosing support scheme to combat soil compaction: Insights from a discrete choice experiment in Germany

CONTEXTFollowing that 60% of the EU's soils are in unhealthy condition, the German government has identified soil protection as a key area of action within the framework of the Agricultural Strategy 2035 as a part of the development of a sustainable agricultural and food system. In particular, harmful compaction of topsoil and subsoil has a negative impact on yield, nitrogen efficiency and greenhouse gas emissions. Slurry hosing is an effective technique to reduce the risk of soil compaction by simultaneously minimising both the number of field passes and the weight of the machinery during slurry spreading. OBJECTIVEThis article assesses farmers' preferences for a stylised slurry hosing support scheme and ascertains the personal and farm characteristics that are likely to affect scheme uptake. METHODSIn a discrete choice survey of 100 German farmers, the respondents were asked to choose among different support schemes and the status quo. The support schemes on offer varied the subsidy rate, the spatial coverage of the scheme, the minimum proportion of a farm's manure to be applied via slurry hosing, the time window for slurry spreading, the commitment period, and the type of compliance monitoring. Since the participants' decision for or against participation in the support programme is binomial, the survey data was analysed by logistic regression in the form of a mixed logit model and a latent-class model. CONCLUSIONA mixed logit results suggest that the majority of respondents valued an extension of the time window for slurry spreading, whereas tighter programme requirements were mostly rejected. The latent-class model revealed three preference classes with different perceptions of the scheme's attributes. Younger farmers with larger farms and suitable site conditions for the hosing technique were identified as a potential target group for the scheme. SIGNIFICANCEOverall uptake rates are likely to remain low should such a scheme be launched. Furthermore, the recommendations for scheme design are not universal. They rather apply only to the group of farmers surveyed, i.e. larger farms with largely favourable site conditions. Since smaller farms may have self-selected themselves out of the survey, it is not permissible to tailor the programme to these very farms on the basis of the results.

Tree species mixing effects on the radial growth of Pinus massoniana and Castanopsis hystrix: A comparison between even-aged and uneven-aged stands

The establishment of mixed-species forests with complex structures and high biodiversity has emerged as a key approach for enhancing productivity and maintaining the stability of plantation forests. However, how the mixing effect changes with stand development and climate variation is still unclear. Additionally, little is known about how the mixing effects vary between even- and uneven-aged mixed planting strategies based on the same species combinations and site conditions. In this study, we used dendrochronological methods to reconstruct 37 years of annual growth series for even-aged mixed plantations (EMs) and uneven-aged mixed plantations (UEMs) of Pinus massoniana and Castanopsis hystrix, as well as their respective monocultures at the individual tree (286 trees in total) level. We found that in EMs, the growth of P. massoniana and C. hystrix was 20.8 % lower and 26.2 % higher than those of their monocultures, respectively. However, the growth of P. massoniana remained unchanged during the first 17 years of mixing, after which it was significantly suppressed by C. hystrix. The growth of P. massoniana and C. hystrix in the UEMs was 20.8 % and 26.2 % lower than that in their monocultures, respectively. Remarkably, the mixing effect on the growth of P. massoniana shifted from suppression to promotion after 30 years of mixing. Furthermore, the relative growth of P. massoniana in the UEMs increased with dry season precipitation. These results indicate that transforming pure plantations into uneven-aged mixed plantations may be a crucial forest management strategy for enhancing tree growth and to improving adaptation to future precipitation pattern changes. However, in EMs, thinning should be conducted before fast-growing, shade-intolerant species experience intense light competition.

Крупные древесные остатки в коренных и вторичных среднетаежных ельниках

Restoration of the pool of coarse woody debris after disturbances is one of the mechanisms for maintaining the stability of forest biogeocenoses. The studies of coarse woody debris have been carried out in the “Vepssky Forest” Reserve in the Leningrad Region on 8 sample plots established in primary forests (4 sample plots) and in secondary forests of the 1st generation after logging in 1973–1974 (4 sample plots), where the composition and structure of the stand, as well as the site conditions have been identical to those in primary forests. The coarse woody debris has been inventoried on transects. The stocks of coarse woody debris in primary stands have ranged from 104 to 233 m3 ha–1. Windfall and leaning trees have prevailed. The proportion of deadwood in both primary and secondary forests has been low. Clear cutting has significantly changed not only the stock of coarse woody debris, but also its distribution by decay classes and substrate categories. The stocks of coarse woody debris in secondary forests have ranged from 8 to 40 m3 ha–1, and have been mainly represented by stumps. The coarse woody debris of the 4th and 5th decay classes has almost been absent in primary forests, while in secondary forests the proportion of highly decomposed wood remaining after cutting has been about 50 %. The ratio of coarse woody debris and growing stocks has been on average 1:1 and 1:5 in the biogeocenoses of primary and secondary forests, respectively. The annual carbon balance of coarse woody debris (the difference in fluxes due to the loss of growing forest and the decay of coarse woody debris) has ranged from 0,40 to 2,80 t C ha–1 year–1, averaging 1,75 and 0,63 t C ha–1 year–1 in secondary and primary forests, respectively. The positive annual carbon balance in the coarse woody debris is due to the predominance of the rate of the loss of growing forest over the rate of the decay of coarse woody debris in primary forests as a result of wind disturbances and as a result of self-thinning of the stand in secondary forests.

Study on Dynamic Characteristics of Long-Span Highway-Rail Double-Tower Cable-Stayed Bridge

The long-span dual-purpose highway-rail double-tower cable-stayed bridge has the characteristics of a large span and large load-bearing capacity. Compared with the traditional cable-stayed bridge, its wind resistance and seismic resistance are weaker, and the dynamic characteristics of the bridge are closely related to the wind resistance and seismic bearing capacity of the bridge. This study investigated the influence of the variations of bridge member parameters on the dynamic characteristics of the bridge and then improved the dynamic characteristics of the bridge. To provide the necessary experimental theory for the research work of the long-span dual-purpose highway-rail double-tower cable-stayed bridges, this paper takes the world’s longest span of the dual-purpose highway-rail double-tower cable-stayed bridge as the background, using the finite element analysis software Midas Civil 2022 v1.2 to establish a three-dimensional model of the whole bridge by changing the steel truss beam stiffness, cable stiffness, pylon stiffness, and auxiliary pier position, as well as study the influence of parameter changes on the dynamic characteristics of the bridge. The results show that the dynamic characteristics of the bridge can be enhanced by increasing the stiffness of the steel truss beam, the cable, and the tower. The stiffness of the steel truss beam mainly affects the transverse bending stiffness and flexural coupling stiffness of the bridge. The influence of cable stiffness is weak. The tower stiffness can comprehensively affect the flexural stiffness and torsional stiffness of the bridge. The position of auxiliary piers should be determined comprehensively according to the site conditions. In practical engineering, the stiffness of components can be enhanced according to the weak links of bridges to improve the dynamic characteristics of bridges and save costs.

Site effect on seismic response of buried nuclear power plant structure

The development of multifunctional, multipurpose small modular next generation nuclear reactors has become a trend in designing small-scale nuclear power stations. In this study, taking a new next-generation buried nuclear power structure as the target structure, a 3D finite element model of the site-nuclear power plant structure system was established, and its response at different sites was studied. Using the internal substructure method, this study initially explored the impact of earthquake input and artificial boundary locations on the structural response. The results indicate that the internal substructure method enhances computational efficiency without compromising accuracy. For this model, it is recommended to input earthquake motion close to the structure, set the lateral boundary location to three times the width of the structure, and set the bottom boundary location to two times the depth of the structure. Subsequently, an investigation into the response of the structure at varying site wave velocities is conducted. The results show that as the wave velocity increases, the acceleration response intensifies, while the displacement response diminishes. However, the relationship is nonlinear; the response exhibits less variation with increasing site wave velocity. The seismic response of a structure is profoundly influenced by site conditions, emphasizing the imperative need for careful consideration of specific site characteristics in seismic analyses. In addition, the response pattern of the overall structure is significantly different from that of conventional large surface-sited nuclear power plants, and further research should be conducted on the seismic response characteristics of buried nuclear power plants.

Enabling Building Information Model-driven human-robot collaborative construction workflows with closed-loop digital twins

The introduction of assistive construction robots can significantly alleviate physical demands on construction workers while enhancing both the productivity and safety of construction projects. Leveraging a Building Information Model (BIM) offers a natural and promising approach to driving robotic construction workflows. However, because of uncertainties inherent in construction sites, such as discrepancies between the as-designed and as-built components, robots cannot solely rely on a BIM to plan and perform field construction work. Human workers are adept at improvising alternative plans with their creativity and experience and thus can assist robots in overcoming uncertainties and performing construction work successfully. In such scenarios, it is critical to continuously update the BIM as work processes unfold so that it includes as-built information for the ensuing construction and maintenance tasks. This research introduces an interactive closed-loop digital twin framework that integrates a BIM into human-robot collaborative construction workflows. The robot’s functions are primarily driven by the BIM, but it adaptively adjusts its plans based on actual site conditions, while the human co-worker oversees and supervises the process. When necessary, the human co-worker intervenes in the robot’s plan by changing the task sequence or workspace geometry or requesting a new motion plan to help the robot overcome the encountered uncertainties. A drywall installation case study is conducted to verify the proposed workflow. In addition, experiments are carried out to evaluate the system performance using an industrial robotic arm in a research laboratory setting that mimics a construction site and in the Gazebo simulation. Integrating the flexibility of human workers and the autonomy and accuracy afforded by the BIM, the proposed framework offers significant promise of increasing the robustness of construction robots in the performance of field construction work.

A real-world data analysis of tirzepatide in the FDA adverse event reporting system (FAERS) database.

Tirzepatide, a glucose-dependent insulinotropic polypeptide (GIP) receptor and glucagon-like peptide-1 (GLP-1) receptor agonist, is indicated for chronic weight management in adults with obesity or overweight as an adjunct to a reduced-calorie diet and increased physical activity. However, the safety profile of Tirzepatide-associated adverse events requires comprehensive evaluation. The AE reports from the first quarter of 2022 to the third quarter of 2023 were selected by exploring the FDA Adverse Event Reporting System (FAERS) database. The new and unexpected potenial AE signals were detected using the disproportionality analysis, including reporting odds ratio(ROR), the proportional reporting ratio (PRR) the Bayesian confidence propagation neural network (BCPNN) and the empirical Bayes geometric mean(EBGM). Then the MedDRA was used to systematically classify the results. A total of 1,904,481 case reports were obtained from 2022Q2 to 2023Q3. Forty-sixth tirzepatide-induced ADRs at the preferred terms (PTs) level are associated with 8 system organ class In addition, this study uncovered multiple anticipated ADRs, such as gastrooesophageal reflux disease, dyspepsia, and vomiting, in line with the drug labels. Moreover, unexpected and significant ADRs at PTs level, such as incorrect dose administered, injection site haemorrhage, and increased appetite, were discovered and linked to Injury, poisoning, and procedural complications, General disorders and administration site conditions, and Metabolism and nutrition disorders at the System Organ Class level. This study offered new perspectives on the monitoring, surveillance, and management of adverse drug reactions related to tirzepatide. The outcomes of severe adverse events and their respective detection signals, along with unexpected significant adverse event signals, are important to consider in efforts to enhance clinical medication safety when using tirzepatide.

Allometric estimation models for aboveground and belowground biomass of pre-fire and post-fire vegetation in Scots pine forests

Abstract Wildfires have recently destroyed large areas of forest in Central Europe. After a fire, the post-fire vegetation succession rebuilds previously lost biomass and carbon. Nevertheless, ground vegetation and tree regeneration, as well as belowground biomass, are largely neglected in allometric biomass models. Moreover, most models are calibrated for undisturbed forests, which differ from burned forests in terms of site conditions and species composition. We adapted a model using plant cover and shoot length of herb, graminoid and bryophyte species (PhytoCalc), and a single tree model using shoot length and root collar diameter of juvenile trees to estimate aboveground biomass (AGB) of post-fire species and growth groups, and extended them to estimate belowground biomass. We sampled the most dominant species from the herb and moss layer and the tree regeneration of burned and unburned Scots pine (Pinus sylvestris L.) forests in NE Germany. We successfully calibrated post-fire vegetation models and showed that models for undisturbed forests from the literature mostly underestimate post-fire AGB. Using models from the literature for clear-cuts often improved the estimation of post-fire AGB, but still failed to estimate AGB accurately for some species. Inaccurate estimation of post-fire biomass with these other models can be explained by high irradiance and increased nutrient availability on burned sites, which affect tissue and wood density. We showed that own species- and growth group-specific allometric models calibrated to post-fire vegetation are required to correctly estimate the total (above- and belowground) biomass of post-fire vegetation needed to calculate carbon storage.

Efficiency and benchmarks for photovoltaic power generation amid uncertain conditions

Photovoltaic (PV) power generation systems are highly subject to weather and site conditions, thus, the construction of PV power plant projects must consider these uncertainties. This study analyzes the monthly electricity generation of 249 utility-scale PV power plants in Japan to evaluate their electricity generation efficiency. Applying the generic data envelopment analysis, benchmark values were identified for power generation from PV power plants. Furthermore, we implemented a Monte Carlo experiment to evaluate the impact of variability in solar irradiance and temperature on power generation efficiency. For our analysis, we considered three inputs—solar irradiance, temperature, and installed capacity—and electricity generation as the output. The results showed that inter-regional gap in the efficiency score between the west and north regions is 0.03, and this can be covered by a 0.1 increase in the DC/AC ratio. Additionally, variability in weather conditions affect both the efficiency of a power plant and production possibility frontier, in turn causing the benchmark values for a generic decision-making unit to vary. Increasing the generation capacity of power plants and operating them more efficiently is essential to expanding the use of renewable energy resources.

Membangun Self Love pada Remaja melalui Psikoedukasi

Forming an image of oneself, roles, interests, values, beliefs, and physical changes begins when entering adolescence. This generally makes teenagers vulnerable to low self-esteem due to a lack of self-love. To anticipate this, an effort is needed to build understanding among teenagers regarding self-love so that they can recognize and respect themselves through psychoeducation activities. This psychoeducation activity is carried out using three stages, namely the planning, implementation, and evaluation stages. The planning stage is carried out by surveying the subject's condition and location of the activity site and coordinating with related parties. The implementation stage of psychoeducation activities involves delivering material and cultivating understanding related to self-love. The evaluation stage is done by looking at the pre-test and post-test results. The subjects of this psychoeducational activity were 28 students at SMPN 2 Lemahabang, Cirebon Regency, aged 13-15 years. The instrument was a questionnaire, and psychoeducation activities were implemented for one month. The results of psychoeducation activities show that there is an increase in the understanding of teenagers at SMPN 2 Lemahabang regarding self-love.

Species-specific and environment-sensitive functional traits in six steppe plant species with different roles in community

Plant functional traits are often considered as indicators of plant-environment relationship; however, some plant features can be highly taxonomic-specific. The study of intraspecific trait variation is essential to understand what functional traits are influenced by the phylogeny and what traits are more dependent on environment. We studied six common steppe plant species in two natural vegetation plots near lake Baikal in Southern Siberia different in climate aridity and grazing degree: site 1 - native true grass steppe under lower climate aridity, site 2 - high disturbed sagebrush steppe under higher aridity. Plant functional traits showed different relevance to species and environment. Plant height, leaf thickness (LT), mesophyll cell volume (Vcell), and the chloroplast number per cell had the greatest contribution to differences between species and varied slightly within a species. Photosynthesis (Amax) and transpiration (E) rates, chlorophyll content, mesophyll surface area per leaf area unit (Ames/A) were more dependent on environment than on species. Amax and E decreased in all studied species in more adverse conditions of site 2, however plants differed in mechanisms of these changes. In Stipa krylovii, Artemisia frigida and Potentilla acaulis, most abundant in true steppe (site 1) mesophyll cell sizes, cell and chloroplast number per leaf area decreased in site 2. Other species, Artemisia scoparia, Potentilla bifurca and Allium anisopodium which were more abundant in disturbed steppe (site 2), had larger cells and showed an increase in cell and chloroplast number per leaf area in site 2 and decrease in the photosynthetic capacity of a chloroplast. We concluded that the leaf thickness and cell size belong to species-specific features, whereas Amax, pigment content and integral mesophyll traits as Ames/A are more indicative for plant-environment relationships and their response to growth conditions depend on the ecological strategy of a species.

Reference dynamic power cable of floating offshore wind turbine for thermal and simple fatigue evaluation

With the increased interest in floating offshore wind turbines, there is an increased focus on evaluating the lifetime of the auxiliary systems, such as the mooring lines and the dynamic power cables, because these systems are in-mature compared to bottom-mounted offshore wind farms. This paper proposes a conceptual reference dynamic power cable suitable for the 15 MW NREL reference turbine mounted on the UMaine floater installed at 82 m water depth. This provides a basis for discussing the life evaluation of dynamic cables obtained from aeroelastic simulation of the floating offshore wind turbine platform exposed to the environmental conditions of the South Brittany site in France. An electromagnetic-thermal finite element simulation is used to determine the current capacity of the cable and aeroelastic simulations are used for a simple assessment of the main failure modes as maximum cable tension, minimum bending radius and fatigue damage accumulation.

FLOW-Alaiz benchmark for coupled terrain and array interaction flow models. Baseline Results

The FLOW-Alaiz benchmark is established to enhance flow models in complex terrain, building on insights and datasets from previous IEA Task 31 benchmarks around the same test site. The new benchmark aims to create a composite validation dataset by gathering measurements from different periods, notably, the New European Wind Atlas (NEWA) ALEX17 experiment and the Alaiz Site Calibration (SC) campaign. The overall study focuses on wind conditions relevant to siting, power performance, and energy yield prediction. Initial results use industry-standard flow models as baselines such as SiteFlow and PyWAsP/PyWAsP-CFD, all in neutral steady-state conditions. Public datasets, documentation, and evaluation scripts are available in the FLOW-Hub repository to provide transparency on the evaluation methodology while private data is kept on SGRE premises for blind testing. Baseline results focus on cross-predictions and wind profiles for the North and South sectors. Cross-predictions reveal challenges in the NEWA case due to large elevation differences and complex flow interactions in the valley, while SC campaigns show better performance in more realistic siting conditions. Wind profiles for neutral conditions generally align with expectations with main limitations in the wake of flow-separation and forest canopy zones. A comparison with vertical profiles from the ALEX17 Diurnal Cycles benchmark highlights potential improvements from high-fidelity mesoscale-to-microscale modeling, revealing distinct variations in wind shear and profile characteristics when stability is used to categorize the atmospheric conditions.

Seismic Risk Model for the Beijing–Tianjin–Hebei Region, China: Considering Epistemic Uncertainty from the Seismic Hazard Models

This study presents a probabilistic seismic risk model for the Beijing–Tianjin–Hebei region in China. The model comprises a township-level residential building exposure model, a vulnerability model derived from the Chinese building taxonomy, and a regional probabilistic seismic hazard model. The three components are integrated by a stochastic event-based method of the OpenQuake engine to assess the regional seismic risk in terms of average annual loss and exceedance probability curve at the city, province, and regional levels. The novelty and uniqueness of this study are that a probabilistic seismic risk model for the Beijing–Tianjin–Hebei region in China is developed by considering the impact of site conditions and epistemic uncertainty from the seismic hazard model.