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A theoretical trade‐off between the efficiency and safety of water transport systems in plants is used to explain diverse ecological patterns, from tree size to community structure. Despite its pervasive influence, this theory has marginal empirical support. This may be partially due to obfuscation of associations by wide phylogenetic sampling or non‐standard sampling between studies. To address this, we examine the coordination of structural and anatomical traits linked to hydraulic safety and efficiency in the leaves of an ecologically diverse group of eucalypts. We introduce a new trait for characterising leaf water transport function measured as the cross‐sectional XA at the petiole divided by the downstream leaf area (XLApetiole). Variation in XLApetiole revealed support for a safety‐efficiency trade‐off in eucalypt leaves. XLApetiole was negatively correlated with theoretical petiole xylem conductivity (Ks_petiole) and strongly negatively correlated with leaf cavitation vulnerability (Ψ50leaf). Species with lower Ψ50leaf exhibited petiole xylem with narrower vessels and greater fibre wall area fractions. Our findings highlight XLApetiole as a novel integrative trait that provides insights into the evolution of leaf form and function in eucalypts and holds promise for wider use among diverse species. Summary statement: We introduce a new trait for characterising leaf water transport capacity called XLApetiole. Using a diverse group of eucalypt leaves, we show that variation in XLApetiole captures the widely theorised trade‐off between hydraulic safety and efficiency. [ABSTRACT FROM AUTHOR]

In the context of the resource allocation hypothesis regarding the trade-off between growth and defence, compared with native species, invasive species generally allocate more energy to growth and less energy to defence. However, it remains unclear how global change and nutrient enrichment will influence the competition between invasive species and co-occurring native species. Here, we tested whether nitrogen (N) and phosphorus (P) addition under elevated CO2 causes invasive species (Mikania micrantha and Chromolaena odorata) to produce greater biomass, higher growth-related compounds and lower defence-related compounds than native plants (Paederia scandens and Eupatorium chinense). We grew these native and invasive species with similar morphology with the addition of N and P under elevated CO2 in open-top chambers. The addition of N alone increased the relative growth rate (RGR) by 5.4% in invasive species, and its combination with P addition or elevated CO2 significantly increased the RGR of invasive species by 7.5 or 8.1%, respectively, and to a level higher than that of native species (by 14.4%, P  < 0.01). Combined N + P addition under elevated CO2 decreased the amount of defence-related compounds in the leaf, including lipids (by 17.7%) and total structural carbohydrates (by 29.0%), whereas it increased the growth-related compounds in the leaf, including proteins (by 75.7%), minerals (by 9.6%) and total non-structural carbohydrates (by 8.5%). The increased concentrations of growth-related compounds were possibly associated with the increase in ribulose 1,5-bisphosphate carboxylase oxygenase content and mineral nutrition (magnesium, iron and calcium), all of which were higher in the invasive species than in the native species. These results suggest that rising atmospheric CO2 concentration and N deposition combined with nutrient enrichment will increase the growth of invasive species more than that of native species. Our result also suggests that invasive species respond more readily to produce growth-related compounds under an increased soil nutrient availability and elevated CO2. [ABSTRACT FROM AUTHOR]

The reproductive mode of viviparity has independently evolved in various animal taxa. It refers to the condition in which the embryos or young develop inside the female’s body during gestation, providing advantages such as protection, nutrition, and improved survival chances. However, parasites and diseases can be an evolutionary force that limit the host’s resources, leading to physiological, morphological, and behavioral changes that impose additional costs on both the pregnant female and her offspring. This review integrates the primary literature published between 1980 and 2021 on the parasitism of viviparous hosts. We describe aspects such as reproductive investment in females, offspring sex ratios, lactation investment in mammals, alterations in birth intervals, current reproductive investment, variations between environments, immune system activity in response to immunological challenges, and other factors that can influence the interaction between viviparous females and parasites. Maintaining pregnancy incurs costs in managing the mother’s resources and regulating the immune system’s responses to the offspring, while simultaneously maintaining an adequate defense against parasites and pathogens. Parasites can significantly influence this reproductive mode: parasitized females adjust their investment in survival and reproduction based on their life history, environmental factors, and the diversity of encountered parasites. [ABSTRACT FROM AUTHOR]

Scenario planning is a powerful approach for assessing restoration outcomes under alternative futures. However, developing plausible scenarios remains daunting in complex systems like ecological communities. Here, we used Bayesian multispecies occupancy modeling to develop scenarios to assess woodland restoration outcomes in afforested communities in seven wildlife management areas in Arkansas, U.S.A. Our objectives were (1) to define plausible woodland restoration and afforestation scenarios by quantifying historic ranges of variation in mean tree cover and tree cover heterogeneity from 1986 to 2021 and (2) to predict changes in bird species richness and occupancy patterns for six species of greatest conservation need under two future scenarios: complete afforestation (100% tree cover) and woodland restoration (based on remotely sensed historic tree cover). Using 35 years of remotely sensed tree cover data and 6 years of bird monitoring data, we developed multispecies occupancy models to predict future bird species richness and occupancy under the complete afforestation and woodland restoration scenarios. Between 1986 and 2021, tree cover increased in all study areas—with one increasing 70%. Under the woodland restoration scenario, avian species richness increased up to 20%, and four of six species of greatest conservation need exhibited gains in occupancy probability. The complete afforestation scenario had negligible effects on richness and occupancy. Overall, we found decreasing tree cover to historic levels prior to widespread afforestation would provide community‐level benefits and would do little harm even to forest‐dependent species of conservation concern. Applying multispecies occupancy modeling within a scenario planning framework allows for comparing multiscale trade‐offs between plausible futures. [ABSTRACT FROM AUTHOR]

A large body of knowledge about life-history traits has arisen from research on viviparous fishes of the family Poeciliidae. Still, the wide variation among species in reproductive strategies provides an excellent opportunity to further explore how life-history traits covary and the causes of covariation patterns. In this study, we provide information on brood size, offspring mass at birth, and total reproductive allotment of six poeciliid species (Gambusia sexradiata, Poeciliopsis latidens, Poeciliopsis viriosa, Priapella intermedia, Pseudoxiphophorus jonesii, and Xiphophorus hellerii). Also, we searched for a trade-off between the number of offspring that females produce and the size of each individual offspring. We tested the hypothesis that this trade-off should be stronger in small females because of the space constraints in the reproductive tract that are inherent to a small body size. If this hypothesis were correct, we expected a strong negative relationship between number and size of offspring in small females and a weaker or undetectable relationship between these two life-history traits in larger females. We found evidence of such a size-dependent trade-off in only one species. Small females of Po. latidens that produced relatively large broods experienced the cost of a reduction in the average size of each offspring. In larger females this negative relationship was weaker. Unexpectedly, we found no evidence of this trade-off in the other five poeciliid species and, in contrast, in one species (Priapella intermedia) females that produced numerous embryos were also capable of producing relatively large embryos. We discuss potential explanations for the different patterns of covariation (or lack of covariation) between number and size of offspring that we detected in these viviparous species. [ABSTRACT FROM AUTHOR]

Background: Evolutionary medicine builds on evolutionary biology and explains why natural selection has left us vulnerable to disease. Unfortunately, several misunderstandings exist in the medical literature about the levels and mechanisms of evolution. Reasons for these problems start from the lack of teaching evolutionary biology in medical schools. A common mistake is to assume that "traits must benefit the species, as otherwise the species would have gone extinct in the past" confusing evolutionary history (phylogeny) with evolutionary function (fitness). Summary: Here we summarise some basic aspects of evolutionary medicine by pointing out: (1) Evolution has no aim. (2) For adaptive evolution to occur, a trait does not have to be beneficial to its carrier throughout its entire life. (3) Not every single individual carrying an adaptive trait needs to have higher than average fitness. (4) Traits do not evolve for the benefit of the species. Using examples from the field of neuroimmunomodulation like sickness behaviour (nervous system), testosterone (hormones), and cytokines (immunity), we show how misconceptions arise from not differentiating between the explanatory categories of phylogeny (evolutionary history) and evolutionary function (fitness). Key Messages: Evolution has no aim but is an automatism that does not function for the benefit of the species. In evolution, successful individuals are those that maximise the transmission of their genes, and health and survival are just strategies to have the opportunity to do so. Thus, a trait enabling survival of the individual until reproductive age will spread even if at later age the same trait leads to disease and death. Natural and sexual selection do not select for traits that benefit the health or happiness of the individual, but for traits that increase inclusive fitness even if this increases human suffering. In contrast, our humane aim is to increase individual well-being. Evolutionary medicine can help us achieve this aim against evolutionary constraints. [ABSTRACT FROM AUTHOR]

In the context of the resource allocation hypothesis regarding the trade-off between growth and defence, compared with native species, invasive species generally allocate more energy to growth and less energy to defence. However, it remains unclear how global change and nutrient enrichment will influence the competition between invasive species and co-occurring native species. Here, we tested whether nitrogen (N) and phosphorus (P) addition under elevated CO2 causes invasive species (Mikania micrantha and Chromolaena odorata) to produce greater biomass, higher growth-related compounds and lower defence-related compounds than native plants (Paederia scandens and Eupatorium chinense). We grew these native and invasive species with similar morphology with the addition of N and P under elevated CO2 in open-top chambers. The addition of N alone increased the relative growth rate (RGR) by 5.4% in invasive species, and its combination with P addition or elevated CO2 significantly increased the RGR of invasive species by 7.5 or 8.1%, respectively, and to a level higher than that of native species (by 14.4%, P  < 0.01). Combined N + P addition under elevated CO2 decreased the amount of defence-related compounds in the leaf, including lipids (by 17.7%) and total structural carbohydrates (by 29.0%), whereas it increased the growth-related compounds in the leaf, including proteins (by 75.7%), minerals (by 9.6%) and total non-structural carbohydrates (by 8.5%). The increased concentrations of growth-related compounds were possibly associated with the increase in ribulose 1,5-bisphosphate carboxylase oxygenase content and mineral nutrition (magnesium, iron and calcium), all of which were higher in the invasive species than in the native species. These results suggest that rising atmospheric CO2 concentration and N deposition combined with nutrient enrichment will increase the growth of invasive species more than that of native species. Our result also suggests that invasive species respond more readily to produce growth-related compounds under an increased soil nutrient availability and elevated CO2. [ABSTRACT FROM AUTHOR]

The trade-offs between ecosystem services directly affect the quality of the ecological environment and the survival and development of human society, which is of great concern to academia, governments, and non-governmental organizations. Guangdong Province is a strong economic performer in China; hence, we selected it to explore the trade-off and synergy differences between different ecosystem services, and to investigate the mechanisms of their influence in economically developed regions with a large population density. Our results showed three main points: (1) The ecosystem services in Guangdong Province showed clear spatial heterogeneity. In addition, northern Guangdong has high levels of water retention, with a value of 5804.73 × 104 m3/km2 and high values for carbon sequestration and soil retention. Western Guangdong is a functional area for food production, and the Pearl River Delta is an economically developed region with low levels of ecosystem services. (2) Overall, in Guangdong Province, three pairs of ecosystem services, namely water retention–soil retention, carbon sequestration–water retention, and carbon sequestration–soil retention, showed a strong positive correlation and good synergistic relationships. The other three pairs of relationships show strong trade-off effects. (3) The relationships between similar ecosystem services show completely different characteristics in different regions. Carbon sequestration and water retention, carbon sequestration and biodiversity conservation, water retention and biodiversity conservation, and soil retention and biodiversity conservation were mainly manifested in high–high synergies, particularly in northern Guangdong; carbon sequestration and soil retention and water retention and soil retention, primarily manifested synergies; carbon sequestration and food production, water retention and food production, and soil retention and food production mainly manifested as trade-off relationships. [ABSTRACT FROM AUTHOR]

Context. In Nepal, naur are usually the staple wild prey for the snow leopard, a solitary stalker hunter, and in some cases, for the wolf who hunts in a pack. We assumed that naur would adapt their anti-predatory responses to the presence of chasing and ambushing predators in the Manang Valley, where there are snow leopards and wolves, and in the Nar Phu valley, an area where there is only the snow leopard. Aims. The aim of this study was to determine if there were differences in anti-predator strategies (vigilance, habitat selection and escape terrain) of naur in two valleys over two seasons, spring and autumn. Methods. In spring 2019, we conducted a reconnaissance survey on the status of the naur and its habitat in the Manang and Nar Phu valleys of the Annapurna Conservation Area, Nepal. In spring and autumn 2020 and 2021, we observed 360 focal naur individuals (180 individuals in each valley), using the vigilance behaviour methodology to examine the behaviour of the naur. Key results. There was little difference in the size of the naur groups between the Manang and Nar Phu valleys. The naur were twice as vigilant in Manang (15%), where there are snow leopards and wolves, as they were in Nar Phu (9%), with only snow leopards. The distance from the naur to escape cover was significantly shorter in Manang than in Nar Phu valley. Naur used significantly more rolling terrain in Nar Phu than in Manang. Conclusions. The return of wolves to the Manang valley may have resulted in an increase in the level of naur vigilance. Most likely, the wolves in Manang have already had an effect on the female-to-young-ratio, and this effect will possibly have important consequences forthe naur population, as well as at the ecosystem level in the future. Other key determining factors, such as the climate crisis and changes in local resources, could have a significant impact on the naur population, indicating the need for more research. Implications. The findings of this study would provide valuable baseline information for the design of a science-based conservation strategy for conservation managers and scientists on naur, snow leopards and wolves. [ABSTRACT FROM AUTHOR]

Implementing practices aiming at both sustainable and resilient supply chains is a nascent but still poorly addressed research area. This study aims at exploring how to develop sustainable and resilient supply chain practices, advancing knowledge on synergies and trade-offs that can be expected. Empirical evidence from six firms has been collected by means of semi-structured interviews. The preliminary results obtained show that sustainability practices are more explicitly implemented by firms, while resilience practices are sometimes neglected. Various degrees of synergies and trade-offs are highlighted: besides being the most widely implemented practices, green logistics, certifications, and eco-design practices can be considered both sustainable and resilient. The implications of this study may be important to expand knowledge on what is regarded as both sustainable and resilient, and it supports organizations throughout their supply chains in the implementation of practices. [ABSTRACT FROM AUTHOR]

Introduction: Island ecosystems often have a disproportionate number of endemic species and unique and fragile functional characteristics. However, few examples of this type of ecosystem have been reported. Methods: We conducted a comprehensive field study on Neilingding Island, southern China. The leaf samples of 79 subtropical forest tree species were obtained and their functional traits were studied in the dry and wet seasons to explain the relationships between plant functional traits and soil nutrients. Results: We found a greater availability of soil moisture content (SMC) and nutrients in the wet season than in the dry season. The values of wet season soil available phosphorus (5.97 mg·kg-1), SMC (17.67%), and soil available potassium (SAK, 266.96 mg·kg-1) were significantly higher than those of the dry season. The leaf dry matter content, specific leaf weight, leaf density, leaf total carbon, leaf total nitrogen, leaf total calcium, and the N/P and C/P ratios of leaves were all significantly higher in the dry season than in the wet season, being 18.06%, 12.90%, 12.00%, 0.17%, 3.41%, 9.02%, 26.80%, and 24.14% higher, respectively. In contrast, the leaf area (51.01 cm2), specific leaf area (152.76 cm2·g-1), leaf water content (0.59%), leaf total nitrogen (1.31%), leaf total phosphorus (0.14%), and leaf total magnesium (0.33%) were much lower in the dry season than in the wet one. There were significant pairwise correlations between leaf functional traits, but the number and strength of correlations were significantly different in the dry and wet seasons. The SAK, soil total phosphorus (STP), and pH impacted plant leaf functional traits in the dry season, whereas in the wet season, they were affected by SAK, STP, pH, and NO3 - (nitrate). Discussion: Both soil nutrients and water availability varied seasonally and could cause variation in a number of leaf traits. [ABSTRACT FROM AUTHOR]

Summary: Supporting food security while maintaining ecosystem sustainability is one of the most important global challenges for humanity. Optimization of cropping systems is expected to promote the ecosystem services of agroecosystems. Yet, how and why cropping system influences the trade‐offs between economic profitability and multiple ecosystem services remain poorly understood.We investigate the influence of six cropping systems on trade‐offs between economic profitability and multiple ecosystem services after considering 36 agricultural ecosystem properties using field experiment data from 2020 to 2022.We show that designing cropping system is a critical tool to closing the gap between ecosystem sustainability and commercial profitability. Cropping system with three harvests within 2 yr had higher performance in overall ecosystem multiple services through enhancement of supporting, regulating, and economic performance without compromising provisioning compared with four other systems. These systems diminished the trade‐off among multiple services, resulting in a 'win‐win' situation for economics and multiple services. By contrast, the monoculture and double cropping systems lead to a strong trade‐off between pairwise services including ecosystem health and profitability.Our work illustrates the substantial potential of rotation systems with three harvests within 2 yr in enforcing ecosystem services and closing the trade‐offs among multiple agricultural ecosystem services. [ABSTRACT FROM AUTHOR]

Ocean warming has caused coral mass bleaching and mortality worldwide and the persistence of symbiotic reef‐building corals requires rapid acclimation or adaptation. Experimental evolution of the coral's microalgal symbionts followed by their introduction into coral is one potential method to enhance coral thermotolerance. Heat‐evolved microalgal symbionts of the generalist species, Cladocopium proliferum (strain SS8), were exposed to elevated temperature (31°C) for ~10 years, and were introduced into four genotypes of chemically bleached adult fragments of the scleractinian coral, Galaxea fascicularis. Two of the four coral genotypes acquired SS8. The new symbionts persisted for the 5 months of the experiment and enhanced adult coral thermotolerance, compared with corals that were inoculated with the wild‐type C. proliferum strain. Thermotolerance of SS8‐corals was similar to that of coral fragments from the same colony hosting the homologous symbiont, Durusdinium sp., which is naturally heat tolerant. However, SS8‐coral fragments exhibited faster growth and recovered cell density and photochemical efficiency more quickly following chemical bleaching and inoculation under ambient temperature relative to Durusdinium‐corals. Mass spectrometry imaging suggests that algal pigments involved in photobiology and oxidative stress were the greatest contributors to the thermotolerance differences between coral hosting heat‐evolved versus wild‐type C. proliferum. These pigments may have increased photoprotection in the heat‐evolved symbionts. This is the first laboratory study to show that thermotolerance of adult corals (G. fascicularis) can be enhanced via the uptake of exogenously supplied, heat‐evolved symbionts, without a trade‐off against growth under ambient temperature. Importantly, heat‐evolved C. proliferum remained in the corals in moderate abundance 2 years after first inoculation, suggesting long‐term stability of this novel symbiosis and potential long‐term benefits to coral thermotolerance. [ABSTRACT FROM AUTHOR]

Production possibility frontier (PPF) in economics denotes the set of all efficient combinations of the amounts of two or more goods that can be produced from the given resources and within the given technology. In the ecosystem services context, it corresponds to all efficient combinations of the amounts of two or more ecosystem services that can be obtained from the given land area within the given management framework. PPF thus captures the conflict, or trade-off, between the production of different goods or services. However, there is a lack of an agreed understanding of what precisely in a PPF expresses the degree of that conflict. This lack of clarity may greatly confound the discussions on trade-offs. This paper tries to answer the two following questions: (1) what exactly is trade-off in the PPF context? (2) how to effectively measure and compare trade-offs across PPFs? In response to the second question, a quantitative generic measure of trade-off severity is proposed. [ABSTRACT FROM AUTHOR]

Urbanization is an important factor affecting ecosystem services (ESs) and their trade-offs. However, little is known about the responses of ES trade-offs to urbanization at different scales. Here, the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model was used to evaluate water yield (WY), water purification (WP), carbon storage (CS), and habitat quality (HQ) in Erhai Lake Basin using earth observation data, and the percentage of urban land (PUL), population density (POP), gross domestic product (GDP), and night light index (NLI) were used as urbanization indicators. We quantified the ES trade-offs using the root mean square error and analyzed spatiotemporal changes in urbanization indicators, ESs, and their trade-offs. Finally, we characterized the relationship between urbanization and ES trade-offs using correlation analysis and curve regression at the grid and town scales. From 2000 to 2020, values of PUL/GDP/NLI/POP were high in the south and low in the north; specifically, they were 15, 8, 2, and 0.42 times higher in the south than in the north, respectively. The urban expansion area in the Erhai Basin from 2000 to 2020 resulted in a 123.24% and 77.03% increase in WY and WP, respectively, and a 32.38% and 100% decrease in CS and HQ, respectively. The trade-offs between WY and CS and between WY and HQ increased, and other ES trade-offs decreased. Urbanization was significantly correlated with most ES trade-offs at the grid scale, but not at the town scale. There was a significant positive correlation between all urbanization indicators and the trade-off between CS and WP (p < 0.05), and the magnitude of the correlation increased with scale. The relationship between ES trade-offs and urbanization was mostly U-shaped and inverted U-shaped at the grid scale, but N-shaped and inverted N-shaped at the town scale. This study provides information that could be used for multi-scale urban planning. [ABSTRACT FROM AUTHOR]

The high energy particles in the space environment will perturb integrated circuits, resulting in system errors or even failures, which is also known as single event effects (SEE). To ensure the normal operation of space systems, it is first necessary to detect these errors. However, detection algorithms also bring additional overhead to the system and reduce its performance. Therefore, we aim to find a trade-off between reliability and performance. To this end, we propose a quantitative evaluation model for detection methods that evaluates the reliability gain of different detection methods under the same overhead. Our method allocates the optimal detection method to the corresponding code segment based on the quantitative results, thereby achieving a trade-off between reliability and performance. Experimental results show that the average energy efficiency of our trade-off method is 91.34%, which is 21.49% higher than the other methods. [ABSTRACT FROM AUTHOR]

Immune responses are energetically costly to produce and often trade off with investment in reproduction and offspring provisioning. We predicted that hosts can interpret the magnitude of the infection threat from cues like initial bacterial load to adjust reproductive investment into offspring quantity and quality.To test this prediction, we exposed female flour beetles (Tribolium castaneum) to naïve or sterile media controls or one of three increasing doses of heat‐killed Bacillus thuringiensis (Bt). To estimate offspring quantity, we measured the number of eggs and hatched larvae from each maternal treatment group. To estimate offspring quality, we measured egg protein content, development to pupation, pupal weight and offspring survival against Bt infection.Compared to naïve controls, low and intermediate bacterial doses resulted in lower female fecundity, suggesting a shift to a somatic maintenance strategy. Meanwhile, in the highest‐dose group, fecundity was negatively correlated with egg protein content. This may reflect a trade‐off between offspring quality and quantity that could mask terminal investment based on metrics of quantity alone.Our results underscore the need to account for the magnitude of environmental cues when quantifying plasticity and trade‐offs among life history traits, and provide new insight into the transgenerational effects of immune responses. [ABSTRACT FROM AUTHOR]

Federated learning (FL) enables participating parties to collaboratively build a global model with boosted utility without disclosing private data information. Appropriate protection mechanisms have to be adopted to fulfill the opposing requirements in preserving privacy and maintaining high model utility. In addition, it is a mandate for a federated learning system to achieve high efficiency in order to enable large-scale model training and deployment. We propose a unified federated learning framework that reconciles horizontal and vertical federated learning. Based on this framework, we formulate and quantify the trade-offs between privacy leakage, utility loss, and efficiency reduction, which leads us to the No-Free-Lunch (NFL) theorem for the federated learning system. NFL indicates that it is unrealistic to expect an FL algorithm to simultaneously provide excellent privacy, utility, and efficiency in certain scenarios. We then analyze the lower bounds for the privacy leakage, utility loss, and efficiency reduction for several widely-adopted protection mechanisms, including Randomization, Homomorphic Encryption, Secret Sharing, and Compression. Our analysis could serve as a guide for selecting protection parameters to meet particular requirements. [ABSTRACT FROM AUTHOR]

In the Loess Plateau, gaining insights into the water storage and soil retention functions of diverse vegetation types, especially, in the semi‐arid watersheds is crucial for identifying the key factors necessary to ensure sustainable development and achieve land degradation neutrality. In this study, five different land use types such as forest, shrub, artificial grass, and natural grasslands were surveyed from 2014 to 2020. Meanwhile, bare land was also used as a control plot. The trade‐off between erosion mitigation and water consumption indicator was quantified based on the ecosystem services perspective benefits. Our results showed that there are significant differences among different land use types (p < 0.05): natural grassland > shrubs > artificial grassland > forests. Vegetation restoration was able to change the soil particle size distribution, increasing clay and silt content, and decreasing sand particles. During the growing season, surface soil water storage decreased in all land use types coinciding with the higher decrease in the control plot. The change in surface water storage in the forest was the most stable, with a decrease of 0.13 mm. The trade‐off between erosion mitigation and water consumption indicator was less than 0 for all vegetation types, which indicates a synergistic effect on soil conservation and water storage benefit. Our results demonstrated that shrubs can register the most balanced benefit of water storage and soil preservation. This is a solid basis for the selection of specific vegetation types and the optimization of the watershed landscape in the middle reaches of the Yellow River, characterized by vulnerable areas due to aridification. [ABSTRACT FROM AUTHOR]

Qualitative Constraint Networks (QCN s) comprise a Symbolic AI framework for representing and reasoning about spatial and temporal information via the use of natural disjunctive qualitative relations, e.g., a constraint can be of the form "Task A is scheduled after or during Task C". In qualitative constraint-based reasoning, the state-of-the-art approach to tackle a given QCN consists in employing a backtracking algorithm, where the branching decisions during search and the refinement of the QCN are governed by certain heuristics that have been proposed in the literature. Although there has been plenty of research on how these heuristics compare and behave in terms of checking the satisfiability of a QCN fast, to the best of our knowledge there has not been any study on how they compare and behave in terms of obtaining a tractable refinement of a QCN that is also robust. In brief, a robust refinement of a QCN can be primarily seen as one that retains as many qualitative solutions as possible, e.g., the configuration "Task A is scheduled after or during Task C" is more robust than "Task A is scheduled after Task C". Here, we make such a preliminary comparison and evaluation with respect to prominent heuristics in the literature, and reveal that there exists a trade-off between fast and robust solving of QCN s for datasets consisting of instances of Allen's Interval Algebra and Region Connection Calculus. Furthermore, we investigate reasons for the existence of this trade-off and find that more aggressive heuristics are more efficient at the cost of producing less robust refinements. [ABSTRACT FROM AUTHOR]

Rural logistics faces a dilemma between development and high carbon emissions in China. We assess the tension between rural logistics development and carbon emissions from the perspective of policy guidance by modeling a rural logistics system using Jiangsu's data. We simulate the development trend of Jiangsu rural logistics under carbon abatement policies from 2021–2030, with a focus on promoting its development while simultaneously reducing carbon emissions at a minimal cost. The findings show that rural logistics will move towards high carbon emissions without a carbon abatement policy, while the huge tax pressure of carbon reduction policies reduces the profitability of rural logistics, leading to a trade-off between development and decarbonization. From the perspective of implementation timing and manner of carbon abatement policies implementation, we propose a pathway for securing the profitability of rural logistics and resolving the trade-off. [ABSTRACT FROM AUTHOR]

Indirect land use change (ILUC) is considered a significant challenge, resulting from an increasing demand for biomass and bioenergy. On a political level sustainability certification of biomass-derived products is discussed as one potential instrument to manage the risk of ILUC. However, extending existing schemes towards a credible and reliable certification approach to account for ILUC-risks is still an open challenge. To develop such a certification instrument, so-called "additionality practices" are gaining relevance. Such practices include measures that an individual producer can adopt to provide an amount of biomass in addition to the business-as-usual feedstock production. This applies in particular to the certification of low ILUC-risk biofuels through voluntary certification schemes recognised by the European Commission. To date, however, no studies have been conducted that examine how such schemes account for potential trade-offs that may arise from the use of additionality practices. In preparation of an integrated assessment framework for low ILUC-risk certification, this study presents a gap analysis that examines whether such trade-offs are considered already in existing sustainability certification schemes for biofuels. In this way, we have found trade-offs that are preferentially addressed by the schemes, e.g., biodiversity loss, on the one hand, and considerable gaps for certain trade-offs, e.g., resource depletion, on the other. In addition, we identified biomass cultivation on unused land as the most promising additionality practice. Most schemes already have certification instruments in place to verify the large number of trade-offs that could be identified as preferentially addressed for this additionality practice. Moreover, only a few new criteria and indicators need to be developed for the small number of gaps found for biomass cultivation on unused land. Finally, this paper recommends future work to verify the scientific evidence of existing certification instruments for the trade-offs addressed and to develop assessment approaches for the identified gaps. [ABSTRACT FROM AUTHOR]

Non-Orthogonal Multiple Access (NOMA) is a promising energy-efficient technology designed to satisfy the demands of future networks by efficiently sharing radio resources. In NOMA, the same radio resource is simultaneously assigned to two users at different power levels based on the NOMA-power domain. Resource allocation in NOMA presents a non-convex challenge, characterized as a non-deterministic polynomial (NP-hard) problem. This involves user and channel assignment and power allocation, making it an extraordinarily complex task to achieve an optimal solution. In this work, Simulated Annealing (SA) is proposed as an optimization technique for resource allocation in an energy-efficient downlink NOMA system. This resource allocation scheme addresses user and channel assignment, as well as power allocation, using SA as an efficient standalone approach to maximize energy efficiency in NOMA. SA is utilized to execute the assignment of users to channels, distribute the necessary power for each channel, and determine the power ratio among users sharing the same channel. The results obtained demonstrate a significant improvement in energy efficiency, outperforming the existing numerical methods by 22 %. The proposed SA scheme not only achieves a close optimal solution but also in less computational time, offering sufficient reliability in terms of energy efficiency enhancement when compared to the existing numerical method.

Airborne dispersal of microorganisms is a ubiquitous migration mechanism, allowing otherwise independent microbial habitats to interact via biomass exchange. Here, we study the ecological implications of such advective transport using a simple spatial model for bacteria–phage interactions: the population dynamics at each habitat are described by classical Lotka–Volterra equations; however, species populations are taken as integer, that is, a discrete, positive extinction threshold exists. Spatially, species can spread from habitat to habitat by stochastic airborne dispersal. In any given habitat, the spatial biomass exchange causes incessant population density oscillations, which, as a consequence, occasionally drive species to extinction. The balance between local extinction events and dispersal-induced migration allows species to persist globally, even though diversity would be depleted by competitive exclusion, locally. The disruptive effect of biomass dispersal thus acts to increase microbial diversity, allowing system-scale coexistence of multiple species that would not coexist locally.

Animals are expected to respond flexibly to changing circumstances, with multimodal signalling providing potential plasticity in social interactions. While numerous studies have documented context-dependent behavioural trade-offs in terrestrial species, far less work has considered such decision-making in fish, especially in natural conditions. Coral reef ecosystems host 25% of all known marine species, making them hotbeds of competition and predation. We conducted experiments with wild Ambon damselfish (Pomacentrus amboinensis) to investigate context-dependent responses to a conspecific intruder; specifically, how nest defence is influenced by an elevated predation risk. We found that nest-defending male Ambon damselfish responded aggressively to a conspecific intruder, spending less time sheltering and more time interacting, as well as signalling both visually and acoustically. In the presence of a model predator compared to a model herbivore, males spent less time interacting with the intruder, with a tendency towards reduced investment in visual displays compensated for by an increase in acoustic signalling instead. We therefore provide ecologically valid evidence that the context experienced by an individual can affect its behavioural responses and multimodal displays towards conspecific threats.

Suburban rural ecosystem, especially those adjacent to large cities, constitute a key component of rural and urban sustainability and resilience. However, urbanisation often exerts a negative impact on suburban rural landscapes, leading to ecological degradation. Despite making a significant contribution to multiple ecosystem services (ESs), suburban rural landscapes do not receive commensurate attention compared to urban themes, particularly on a smaller scale. We explored key drivers of land use dynamics in the suburban rural area of Jiangning, Nanjing, China, via a quantitative statistical mapping approach, utilising multi-source geospatial data from 2005 to 2018 and relevant ecological and socio-economic data that would enable the quantification of four key ecosystem services. Landscape functional zones characterised by ESs bundles were also identified, and their association with surrounding landscape attributes was statistically analysed. Our results highlighted urbanisation-induced population growth as the macro-context driving the development of Jiangning. The analysis yielded five distinct landscape functional zones (LFZs) that displayed synergistic relationships between their ESs, namely, carbon storage and soil retention, n-output and water yield. Furthermore, these results linked LFZs to environmental spatial characteristics and created detailed landscape elements for each zone, thereby emphasising the need for more comprehensive landscape planning and designing for ecological transition zones. We were thus able to imply zoning attributes-based rural landscape designs that may optimise ecological benefits. This study provides a systematic method to integrate ESs, landscape functional zones, and environmental spatial characteristics into the whole process management of suburban rural landscape planning. It aims to promote sustainable multifunctionality in suburban rural areas by providing spatial-level management indicators and landscape element-level design strategies for each LFZ, thereby revitalising the countryside from the perspective of landscape architecture.

Background: The study was carried out to analyze the temporal changes of trade-offs (TOs) between two ecosystem services (ESs) before and after thinning in a Pinus koraiensis plantation on Mt. Gari from 2006 to 2021. As target variables, aboveground carbon (AGC) storage and species richness (SR) were chosen for regulating and supporting services. Thinning was applied from 2007 through 2008 with three treatments: 1) light thinning (LT), 2) heavy thinning (HT), and 3) control (Con).Results: Thinning influenced both AGC and SR. In 2021, AGC in the Con (111.1 t C ha-1) was significantly higher compared to the LT (82.0 t C ha-1) and HT (60.4 t C ha-1) after thinning from 2007 to 2008. Also, SR was marginally higher in the LT (94 species) than in the Con (55 species) and HT (87 species) in 2011. Relative benefits of AGC and SR showed similar trends with the obtained values. In addition, the effects of thinning on TO varied among treatments and over time, demonstrating different degrees of TO between the two ESs. In the LT, TO was 0.13 in 2006 and slightly increased to 0.2 by 2021. TO in the HT exhibited a relatively rapid increase from 0.22 in 2006 to 0.58 by 2021, while To in the Con fluctuated, rising to 0.36 in 2011 from 0.1 in 2006 and decreasing to 0.25 by 2021. Among the three treatments, the degree of TOs between the two ESs was the lowest in the LT.Conclusions: Depending on thinning intensities, the responses of ESs and the degree of TOs vary. Regarding the balance between enhancements and TOs in ESs among treatments, the LT treatment showing intermediate carbon storage, higher SR, and lower TOs will be a proper silvicultural application.

Student dropout prediction (SDP) in educational research has gained prominence for its role in analyzing student learning behaviors through time series models. Traditional methods often focus singularly on either prediction accuracy or earliness, leading to sub-optimal interventions for at-risk students. This issue underlines the necessity for methods that effectively manage the trade-off between accuracy and earliness. Recognizing the limitations of existing methods, this study introduces a novel approach leveraging multi-objective reinforcement learning (MORL) to optimize the trade-off between prediction accuracy and earliness in SDP tasks. By framing SDP as a partial sequence classification problem, we model it through a multiple-objective Markov decision process (MOMDP), incorporating a vectorized reward function that maintains the distinctiveness of each objective, thereby preventing information loss and enabling more nuanced optimization strategies. Furthermore, we introduce an advanced envelope Q-learning technique to foster a comprehensive exploration of the solution space, aiming to identify Pareto-optimal strategies that accommodate a broader spectrum of preferences. The efficacy of our model has been rigorously validated through comprehensive evaluations on real-world MOOC datasets. These evaluations have demonstrated our model’s superiority, outperforming existing methods in achieving optimal trade-off between accuracy and earliness, thus marking a significant advancement in the field of SDP.

Common bean is often considered a woman’s crop because they play important roles from production to marketing. However, breeding programs often focus on farmers without adequate attention to the interconnectedness between gender and other socioeconomic variables and how they influence varietal and trait preferences of other value chain actors. This study analyzed gendered differences in bean production and trade, implications of socioeconomic conditions on bean production and marketing, and the role of partnerships in closing gender gaps in the bean value chain in Zimbabwe. The results obtained from the analysis of survey data collected from 131 farmers and 18 trades revealed beans as a dual-purpose crop for male and female farmers and traders. Varietal and trait preferences were the same for both male and female farmers and traders but were prioritized differently. While female farmers prioritized cooking time, men farmers prioritized biofortification and market traits. Whereas male traders equally preferred price, color, and appearance, female traders prioritized price over color and appearance. Poverty and marital statuses of respondents influenced the number of varieties preferred by male and female farmers. We found that the effectiveness of partnerships in closing gender gaps in marketing is variety specific. While having partners closed the gender gaps in the marketing of the NUA45 variety, such partnerships did not have the same effect on closing gender gaps in the marketing of Cherry, Gloria, and other varieties. The results show that considering socioeconomic characteristics of actors and partnerships can reduce gender disparities in the bean value chain. Therefore, breeding programs should recognize the interconnectedness between socioeconomic variables and gender when developing breeding products.

Abstract Background The relative treatment effects estimated from network meta-analysis can be employed to rank treatments from the most preferable to the least preferable option. These treatment hierarchies are typically based on ranking metrics calculated from a single outcome. Some approaches have been proposed in the literature to account for multiple outcomes and individual preferences, such as the coverage area inside a spie chart, that, however, does not account for a trade-off between efficacy and safety outcomes. We present the net-benefit standardised area within a spie chart, $$SAWIS$$ SAWIS to explore the changes in treatment performance with different trade-offs between benefits and harms, according to a particular set of preferences. Methods We combine the standardised areas within spie charts for efficacy and safety/acceptability outcomes with a value λ specifying the trade-off between benefits and harms. We derive absolute probabilities and convert outcomes on a scale between 0 and 1 for inclusion in the spie chart. Results We illustrate how the treatments in three published network meta-analyses perform as the trade-off λ varies. The decrease of the $$SAWIS$$ SAWIS quantity appears more pronounced for some drugs, e.g. haloperidol. Changes in treatment performance seem more frequent when SUCRA is employed as outcome measures in the spie charts. Conclusions $$SAWIS$$ SAWIS should not be interpreted as a ranking metric but it is a simple approach that could help identify which treatment is preferable when multiple outcomes are of interest and trading-off between benefits and harms is important.

Amine transaminases (ATAs) catalyze the asymmetric amination of prochiral ketones or aldehydes to their corresponding chiral amines. However, the trade-off between activity and stability in enzyme engineering represents a major obstacle to the practical application of ATAs. Overcoming this trade-off is important for developing robustly engineered enzymes and a universal approach for ATAs. Herein, we modified the binding pocket of ω-ATA from Aspergillus terreus (AtATA) to identify the key amino acid residues controlling the activity and stability of AtATA toward 1-acetonaphthone. We discovered a structural switch comprising four key amino acid sites (R128, V149, L182, and L187), as well as the “best” mutant (AtATA_D224K/V149A/L182F/L187F; termed M4). Compared to the parent enzyme AtATA_D224K (AtATA-Pa), M4 increased the catalytic efficiency (kcat/Km1-acetonaphthone, where kcat is the constant of catalytic activities and is 10.1 min−1, Km1-acetonaphthone is Michaelis-Menten constant and is 1.7 mmol·L–1) and half-life (t1/2) by 59-fold to 5.9 L·min−1·mmol−1 and by 1.6-fold to 46.9 min, respectively. Moreover, using M4 as the biocatalyst, we converted a 20 mmol·L–1 aliquot of 1-acetonaphthone in a 50 mL scaled-up system to the desired product, (R)-(+)-1(1-naphthyl)ethylamine ((R)-NEA), with 78% yield and high enantiomeric purity (R > 99.5%) within 10 h. M4 also displayed significantly enhanced activity toward various 1-acetonaphthone analogs. The related structural properties derived by analyzing structure and sequence information of robust ATAs illustrated their enhanced activity and thermostability. Strengthening of intramolecular interactions and expansion of the angle between the substrate-binding pocket and the pyridoxal 5′-phosphate (PLP)-binding pocket contributed to synchronous enhancement of ATA thermostability and activity. Moreover, this pocket engineering strategy successfully transferred enhanced activity and thermostability to three other ATAs, which exhibited 8%–22% sequence similarity with AtATA. This research has important implications for overcoming the trade-off between ATA activity and thermostability.

Abstract Background Clonal plants can successfully adapt to various ecosystems. A trade-off between sexual and clonal reproduction is generally assumed in clonal plants, which may be influenced both by the characteristics of the plant itself and environmental conditions. Currently, it is unclear how climate change, and specifically warming and increased precipitation, might affect sexual and clonal reproduction in clonal plants. Therefore, this study aimed to investigate both the sexual and clonal reproduction responses of Stipa breviflora to warming and increased precipitation. A controlled experiment was conducted by inducing increases in precipitation (ambient condition, 25% and 50% increases) and warming (ambient temperature, 1.5 °C and 3.0 °C increases). Results Warming significantly influenced both the ratio of reproductive ramet shoot biomass to total shoot biomass, and the ratio of reproductive ramet number to total ramet number. Additionally, the ratio of reproductive ramet shoot biomass to total shoot biomass was also significantly affected by increased precipitation. Increased precipitation benefited sexual reproduction, while effects of warming on reproductive and/or vegetative ramets varied from negative to positive depending on precipitation conditions. There was no relationship between the number or shoot biomass of reproductive ramets and vegetative ramets. Reproductive ramets displayed greater sensitivity to climate change than vegetative ramets. Conclusions The findings of our study suggest that there was no trade-off between sexual and clonal reproduction in S. breviflora. The combined impact of warming and increased precipitation promoted sexual reproduction but did not inhibit clonal reproduction. Clonal plants with the capacity for both sexual and clonal reproduction, may cope with climate change well via clonal reproduction, ensuring their survival.

Moral dilemmas are a useful tool to investigate empirically, which parameters of a given situation modulate participants' moral judgment, and in what way. In an effort to provide moral judgment data from a non-WEIRD culture, we provide the translation and validation of 48 classical moral dilemmas in Persian language. The translated dilemma set was submitted to a validation experiment with N = 82 Iranian participants. The four-factor structure of this dilemma set was confirmed; including Personal Force (Personal, Impersonal), Benefit Recipient (Self, Other), Evitability (Avoidable, Inevitable), and Intentionality (Accidental, Instrumental). When comparing moral judgments of Iranian participants to those of Spanish and Italian participants' from previous research with the same dilemma set, differences emerged. Iranian participants' moral judgments were more deontological (i.e., they refrained from harm), than Spanish and Italian participants. Religiosity made participants' moral judgments more deontological, and also dysphoric mood resulted in a more deontological response style.

Behaviour is often the fundamental driver of disease transmission, where behaviours of individuals can be seen to scale up to epidemiological patterns seen at the population level. Here we focus on animal behaviour, and its role in parasite transmission to track its knock-on consequences for parasitism, production and pollution. Livestock face a nutrition versus parasitism trade-off in grazing environments where faeces creates both a nutritional benefit, fertilizing the surrounding sward, but also a parasite risk from infective nematode larvae contaminating the sward. The grazing decisions of ruminants depend on the perceived costs and benefits of the trade-off, which depend on the variations in both environmental (e.g., amounts of faeces) and animal factors (e.g., physiological state). Such grazing decisions determine the intake of both nutrients and parasites, affecting livestock growth rates and production efficiency. This impacts on the greenhouse gas costs of ruminant livestock production via two main mechanisms: (1) slower growth results in longer durations on-farm and (2) parasitised animals produce more methane per unit food intake. However, the sensitivity of behaviour to host parasite state offers opportunities for early detection of parasitism and control. Remote monitoring technology such as accelerometers can detect parasite-induced sickness behaviours soon after exposure, before impacts on growth, and thus may be used for targeting individuals for early treatment. We conclude that livestock host x parasite interactions are at the centre of the global challenges of food security and climate change, and that understanding livestock behaviour can contribute to solving both.

Diversification at the plot level, through the use of intercropping (mixtures of crops), is an alternative to the conventional system of intensive agriculture, based on monospecific, usually single-variety canopies. Intercropping has been shown to provide benefits in terms of disease control. However, competition phenomena and the heterogeneity of the associated crops raise new ecological questions, particularly with regard to the dynamics and evolution of parasite populations. No study has assessed the potential impact of these associations on the dynamics of pathogenic species complexes. Changes in the nutritional status of plants and therefore in their physiological susceptibility to infection within intercropping systems could contribute to an increased diversity of ecological niches and thus affect the composition of the parasitic complex and its spatiotemporal dynamics. In this review, focusing on foliar diseases of fungal origin, and after outlining some elements of the biology and epidemiology of these fungal diseases, we will (i) describe the mechanisms that contribute to the composition of disease clusters and that drive interactions, but we will also review the strategies that these foliar diseases have adopted to deal with these co-infections; (ii) define how intercropping can lead to changes in epidemic dynamics, in particular by presenting the mechanisms that have a direct and indirect effect on disease evolution; and (iii) present the approach that should be adopted to properly study intercropping correctly in a multi-infection situation.

The failure of perceptual illusions to elicit corresponding biases within movement supports the view of two visual pathways separately contributing to perception and action. However, several alternative findings may contest this overarching framework. The present study aimed to examine the influence of perceptual illusions within the planning and control of aiming. To achieve this, we manipulated and measured the planning/control phases by respectively perturbing the target illusion (relative size-contrast illusion; Ebbinghaus/Titchener circles) following movement onset and detecting the spatiotemporal characteristics of the movement trajectory. The perceptual bias that was indicated by the perceived target size estimates failed to correspondingly manifest within the effective target size. While movement time (specifically, time after peak velocity) was affected by the target configuration, this outcome was not consistent with the direction of the perceptual illusions. These findings advocate an influence of the surrounding contextual information (e.g., annuli) on movement control that is independent of the direction predicted by the illusion. [ABSTRACT FROM AUTHOR]

Abstract Background Numerous studies in the past have expanded our understanding of the genetic differences of global distributed cyanobacteria that originated around billions of years ago, however, unraveling how gene gain and loss drive the genetic evolution of cyanobacterial species, and the trade-off of these evolutionary forces are still the central but poorly understood issues. Results To delineate the contribution of gene flow in mediating the hereditary differentiation and shaping the microbial evolution, a global genome-wide study of bloom-forming cyanobacterium, Microcystis aeruginosa species complex, provided robust evidence for genetic diversity, reflected by enormous variation in gene repertoire among various strains. Mathematical extrapolation showed an ‘open’ microbial pan-genome of M. aeruginosa species, since novel genes were predicted to be introduced after new genomes were sequenced. Identification of numerous horizontal gene transfer’s signatures in genome regions of interest suggested that genome expansion via transformation and phage-mediated transduction across bacterial lineage as an evolutionary route may contribute to the differentiation of Microcystis functions (e.g., carbohydrate metabolism, amino acid metabolism, and energy metabolism). Meanwhile, the selective loss of some dispensable genes at the cost of metabolic versatility is as a mean of adaptive evolution that has the potential to increase the biological fitness. Conclusions Now that the recruitment of novel genes was accompanied by a parallel loss of some other ones, a trade-off in gene content may drive the divergent differentiation of M. aeruginosa genomes. Our study provides a genetic framework for the evolution of M. aeruginosa species and illustrates their possible evolutionary patterns.

As a Muslim-majority country, Indonesia possesses significant potential to harness Islamic banking as a key driver of its economy. This study aims to examine the effects of Sharia-compliant financing provided by Islamic banks in Indonesia on the unemployment rate and economic growth. The analysis utilizes data on Sharia-compliant financing for non-bank third parties, open unemployment rate, and gross regional domestic product at constant prices as proxies for economic growth. Annual panel data from 33 provinces in Indonesia covering 2010 to 2021 are employed. The analysis employs a fixed-effect regression model using the generalized least squares (GLS) estimator. The findings of this study indicate that Sharia-compliant financing has a positive impact on reducing the unemployment rate and fostering economic growth. However, it is observed that the effectiveness of Sharia-compliant financing in reducing unemployment diminishes as the share of such financing increases. Conversely, a higher market share of Sharia-compliant financing is associated with a more significant role in promoting economic growth. These findings highlight a trade-off between the impact of Sharia-compliant financing on growth and unemployment, suggesting that although growth driven by Sharia-compliant financing in Indonesia is present, it may need more inclusivity and more optimal job creation.

Abstract Inducible defences can improve survival in variable environments by allowing individuals to produce defences if they detect predators. These defences are often expressed as inter‐related developmental, morphological, and behavioural changes. However, producing defences can incur costs, which may be expressed immediately and/or during subsequent life stages. In Australia, waterborne cues of potentially cannibalistic conspecific tadpoles induce hatchlings of invasive cane toads to accelerate their developmental rate, thereby reducing their window of vulnerability. However, the mechanisms and costs of such accelerated development are poorly understood, and whether cane toad embryos show cannibal‐induced plasticity in other traits is unknown. Here, we found no evidence of altered time of hatching for embryos exposed to non‐feeding conspecific cannibal tadpole cues. Additionally, hatchling dispersal behaviours were not affected by exposure to these cues. However, developmental acceleration of hatchlings induced by exposure to tadpole cues was accompanied by reduced hatchling growth, indicating a trade‐off between these processes. At the conclusion of the hatchling stage, cannibal‐exposed individuals were smaller and morphologically distinct from control siblings. This size reduction affected performance during the subsequent tadpole stage: smaller cannibal‐exposed individuals were more likely to die, and initial size tended to be positively associated with subsequent tadpole growth and development across treatments (respectively, p = .07 and p = .06). However, even accounting for variation in initial size, there was an additional negative effect of cannibal exposure on tadpole growth and development, demonstrating that the fitness costs associated with developmental acceleration are not entirely attributable to size reductions.

Design occurs in complex socio-technical contexts with conflicting stakeholder goals, requirements and other constraints. These limit solution options and create trade-offs where improvements relative to one goal come at the expense of performance on another. Little is known about how the design context influences trade-offs, or how designers interact with context to manage trade-offs. This article reports on an exploratory qualitative interview study investigating design trade-offs in relation to their socio-technical context. We identified nine themes reflecting engineering designers’ perceptions of the influence of the design context on their ability to resolve trade-offs. Findings suggest that the design context is both a source of trade-offs, and of knowledge and information that helps designers clarify ambiguous requirements to navigate and resolve trade-offs. The results provide insight into how designers interact with the design context to learn about the structure of their design problems and the degrees of freedom available to resolve trade-offs. The findings also contribute to understanding the effects of path dependencies in trade-off situations, and how the sequential distribution of design decisions over time constrains trade-off resolution. We discuss some of the goals and challenges of conducting rigorous qualitative research in design and identify potential directions for further research.

Site conditions and species identity have a combined effect on fine root growth of trees in pure and mixed stands. However, mechanisms that may contribute to this effect are rarely studied, even though they are essential to assess the potential of species to cope with climate change. This study examined fine root overlap and the linkage between fine root and stem growth of European beech (Fagus sylvatica) growing in pure and mixed stands with Douglas fir (Pseudotsuga menziesii) or Norway spruce (Picea abies) at two different study sites in northwestern Germany.The study sites represented substantially different soil and climate conditions. At each site, three stands, and at each stand, three pairs of trees were studied. In the pure beech stand, the pairs consisted of two beech trees, while in the mixed stands each pair was composed of a beech tree and a conifer. Between each pair, three evenly spaced soil cores were taken monthly throughout the growing season. In the pure beech stands, microsatellite markers were used to assign the fine roots to individual trees. Changes in stem diameter of beech were quantified and then upscaled to aboveground wood productivity with automatic high-resolution circumference dendrometers.We found that fine root overlap between neighboring trees varied independently of the distance between the paired trees or the stand types (pure versus mixed stands), indicating that there was no territorial competition. Aboveground wood productivity (wood NPP) and fine root productivity (root NPP) showed similar unimodal seasonal patterns, peaking in June. However, this pattern was more distinct for root NPP, and root NPP started earlier and lasted longer than wood NPP. The influence of site conditions on the variation in wood and root NPP of beech was stronger than that of stand type. Wood NPP was, as expected, higher at the richer site than at the poorer site. In contrast, root NPP was higher at the poorer than at the richer site.We concluded that beech can respond to limited resources not only above- but also belowground and that the negative relationship between above- and belowground growth across the study sites suggests an ‘optimal partitioning’ of growth under stress.

Foraging behavior of pollinators is shaped by, among other factors, the conflict between maximizing resource intake and minimizing predation risk; yet, empirical studies quantifying variation in both forces are rare, compared to those investigating each separately. Here, we discuss the importance of simultaneously assessing bottom-up and top-down forces in the study of plant-pollinator interactions, and propose a conceptual and testable graphical hypothesis for pollinator foraging behavior and plant fitness outcomes as a function of varying floral rewards and predation risk. In low predation risk scenarios, no noticeable changes in pollinator foraging behavior are expected, with reward levels affecting only the activity threshold. However, as predation risk increases we propose that there is a decrease in foraging behavior, with a steeper decline as plants are more rewarding and profitable. Lastly, in high predation risk scenarios, we expect foraging to approach zero, regardless of floral rewards. Thus, we propose that pollinator foraging behavior follows an inverse S-shape curve, with more pronounced changes in foraging activity at intermediate levels of predation risk, especially in high reward systems. We present empirical evidence that is consistent with this hypothesis. In terms of the consequences for plant fitness, we propose that specialized plant-pollinator systems should be more vulnerable to increased predation risk, with a steeper and faster decline in plant fitness, compared with generalist systems, in which pollinator redundancy can delay or buffer the effect of predators. Moreover, whereas we expect that specialist systems follows a similar inverse S-shape curve, in generalist systems we propose three different scenarios as a function not only of reward level but also compatibility, mating-system, and the interplay between growth form and floral display. The incorporation of trade-offs in pollinator behavior balancing the conflicting demands between feeding and predation risk has a promising future as a key feature enabling the development of more complex foraging models.

Understanding understory seedling regeneration mechanisms is important for the sustainable development of temperate primary forests in the context of increasingly intense climate warming events. The poor regeneration of dominant tree species, however, is one of the biggest challenges it faces at the moment. Especially, the regeneration of the shade-intolerant Quercus mongolica seedling is difficult in primary forests, which contrasts with the extreme abundance of understory seedlings in secondary forests. The mechanism behind the interesting phenomenon is still unknown. This study used in-situ monitoring and nursery-controlled experiment to investigate the survival rate, growth performance, as well as nonstructural carbohydrate (NSC) concentrations and pools of various organ tissues of seedlings for two consecutive years, further analyze the understory light availability and simulate the foliage carbon (C) gain in the secondary and primary forest. Results suggested that seedlings in the secondary forest had greater biomass allocation aboveground, height and specific leaf area (SLA) in summer, which allowed the seedling to survive longer in the canopy closure period. High light availability and positive C gain in early spring and late autumn are key factors affecting the growth and survival of understory seedlings in the secondary forest, whereas seedlings in the primary forest had annual negative carbon gain. Through the growing season, the total NSC concentrations of seedlings gradually decreased, whereas those of seedlings in the secondary forest increased significantly in autumn, and were mainly stored in roots for winter consumption and the following year's summer shade period, which was verified by the nursery-controlled experiment that simulated autumn enhanced light availability improved seedling survival rate and NSC pools. In conclusion, our results revealed the survival trade-off strategies of Quercus mongolica seedlings and highlighted the necessity of high light availability during the spring and autumn phenological periods for shade-intolerant tree seedling recruitment.