Resource Trade-offs Research Articles

Ageing effects of social environments in 'non-social' insects.

It is increasingly clear that social environments have profound impacts on the life histories of 'non-social' animals. However, it is not yet well known how species with varying degrees of sociality respond to different social contexts and whether such effects are sex-specific. To survey the extent to which social environments specifically affect lifespan and ageing in non-social species, we performed a systematic literature review, focusing on invertebrates but excluding eusocial insects. We found 80 studies in which lifespan or ageing parameters were measured in relation to changes in same-sex or opposite-sex exposure, group size or cues thereof. Most of the studies focused on manipulations of adults, often reporting sex differences in lifespan following exposure to the opposite sex. Some studies highlighted the impacts of developmental environments or social partner age on lifespan. Several studies explored potential underlying mechanisms, emphasizing that studies on insects could provide excellent opportunities to interrogate the basis of social effects on ageing. We discuss what these studies can tell us about the social environment as a stressor, or trade-offs in resources prompted by different social contexts. We suggest fruitful avenues for further research of social effects across a wider and more diverse range of taxa.This article is part of the discussion meeting issue 'Understanding age and society using natural populations'.

Evaluating time-cost trade-off in a resource constraint GERT-type project scheduling problem considering rework

In practice, rework is a major threat to projects’ performance and increases the risk of not delivering the outcomes on time and budget. The classical project scheduling methods are incapable of considering the rework and stochastic structure for projects in the planning phase. The current study models the stochastic projects through a GERT network in which the occurrence of rework is allowed. The aim is to find the optimal execution mode for each activity so that the project is completed within the desired time and the resource constraint is satisfied. We develop a multi-mode time–cost trade-off resource constraint project scheduling problem under uncertainty to find a here-and-now solution to minimise project completion time. The problem is solved using a combination of flow-graph theory and a branch and bound method for the developed integer programming model. As the project structure is stochastic, a distinct set of all possible realised paths is considered. To the best of our knowledge, there is no similar test instance in the literature, hence, the solution methodology is implemented on a randomly generated numerical example. The reported computational results exhibit the sensitivity of objective function to the changes in available resource amount.

Leveraging group model building to operationalize implementation strategies across implementation phases: an exemplar related to child maltreatment intervention selection

BackgroundImplementation strategies can help support the adoption and implementation of health interventions that are appropriate for a local context and acceptable to decision makers and community members. Implementation strategies should be designed to handle the complexity of the multi-level, dynamic contexts in which interventions are implemented. Systems science theories and methods explicitly attend to complexity and can be valuable for specifying implementation strategies. Group Model Building (GMB) combines research partner engagement strategies with systems science to support researchers’ and partners’ learning about complex problems and to identify solutions through consensus. This paper specifies how GMB can operationalize implementation strategies — methods for supporting evidence implementation in real-world practice — and describes how GMB can aid in selecting and tailoring both health interventions and implementation strategies. A case study in child maltreatment prevention planning is provided to illustrate how GMB was used to specify the “actions” — strategy activities — for three implementation strategies (conduct local consensus discussions; build a coalition; model and simulate change) during the earliest implementation phases, with the goal of supporting intervention selection decisions. Examples are provided of generalizable research products that can be produced concurrently through GMB, in addition to contextually-driven implementation support.MethodsParticipants (n = 8) were engaged over four sessions using tailored GMB activities. Participants generated a qualitative system dynamics model that described their theory of change for how to prevent child maltreatment in their communities. This theory of change reflected a dynamic understanding of the interconnected determinants of child maltreatment.ResultsGMB was acceptable to participants and resulted in products that could be used for implementation planning (e.g., to model and simulate change) and future research. GMB fostered trust and idea sharing between participants.ConclusionGMB can facilitate learning about which outcomes are (or are not) impacted by interventions, which resources and approaches are required for quality implementation (e.g., implementation strategies), and tradeoffs in outcomes and resources between interventions. GMB also provides a structured, effective process to generate a shared implementation vision amongst participants. Lessons learned include methods for developing trust with and between participants, and the need for researchers to tailor GMB actions for participant and project needs.

A Speculative Loop Pipeline Framework with Accurate Path Modeling for High-Level Synthesis

Loop pipelining is a key optimization in High-Level Synthesis (HLS), aimed at overlapping the execution of iterations. Static scheduling, dominant in commercial HLS tools, configures the pipeline based on compile-time analysis, proving conservative for designs with irregular control flow and memory access due to imbalanced recurrences. Speculative Loop pipeline (SLP) is a novel concept that addresses the problem by introducing the speculation and recovery mechanism at the source level to improve the throughput. Although proven promising, it has a significant gap from practical application: It requires accurate early-stage modeling of the pipeline configuration for each path, which is unable to obtain with classic HLS scheduling methods because the SLP process itself interferes with the path length. In this work, we made a step forward by proposing a practical SLP framework with accurate path modeling ability through iterative tuning. We further optimize the SLP technology by combining automatic dataflow extraction with speculative source-level transformation to further boost the performance in specific design patterns. Our framework works on the source level and is easy to be plugged into existing downstream HLS tools. Experiment results demonstrate significant performance improvements over commercial HLS tools and better resource trade-offs compared to the state-of-the-art dynamic-scheduling-based solutions.

Simulation of early season herbivory via mechanical damage affects flower production in pumpkin (Cucurbita pepo ssp. pepo).

Damage from insect herbivores can elicit a wide range of plant responses, including reduced or compensatory growth, altered volatile profiles, or increased production of defence compounds. Specifically, herbivory can alter floral development as plants reallocate resources towards defence and regrowth functions. For pollinator-dependent species, floral quantity and quality are critical for attracting floral visitors; thus, herbivore-induced developmental effects that alter either floral abundance or attractiveness may have critical implications for plant reproductive success. Based on past work on resource trade-offs, we hypothesize that herbivore damage-induced effects are stronger in structural floral traits that require significant resource investment (e.g. flower quantity), as plants reallocate resources towards defence and regrowth, and weaker in secondary floral traits that require less structural investment (e.g. nectar rewards). In this study, we simulated early-season herbivore mechanical damage in the domesticated jack-o-lantern pumpkin Cucurbita pepo ssp. pepo and measured a diverse suite of floral traits over a 60-d greenhouse experiment. We found that mechanical damage delayed the onset of male anthesis and reduced the total quantity of flowers produced. Additionally, permutational multivariate analysis of variance (PERMANOVA) indicated that mechanical damage significantly impacts overall floral volatile profile, though not output of sesquiterpenoids, a class of compounds known to recruit specialized cucumber beetle herbivores and squash bee pollinators. We show that C. pepo spp. pepo reduces investment in male flower production following mechanical damage, and that floral volatiles do exhibit shifts in production, indicative of damage-induced trait plasticity. Such reductions in male flower production could reduce the relative attractiveness of damaged plants to foraging pollinators in this globally relevant cultivated species.

Discrepancy in coordination and variation of root and leaf traits among herbaceous and shrub species in the desert, China.

Alterations in life forms could simultaneously influence the variability of fine root and leaf traits. However, our understanding of the organ-level coordination and patterns of variation in fine root and leaf traits among desert herbs and shrubs with distinct habits remains limited. Consequently, this study examined the leaf and fine root traits of 9 shrubs and 9 herbs across three desert habitats through Sperman's correlation analysis, principal component analysis (PCA), and standardized major axis (SMA) analysis as a means of identifying the hub traits and the resource trade-off strategies employed by desert plants to adapt to their environment. The results showed that the extent of coordination between leaf and root traits, defined as similarity, was contingent upon the life form. While the traits in shrubs were completely decoupled, those in herbs exhibited a high degree of coordination. The traits related to water acquisition and storage are highly connected and do not depend on traits and life forms. Most leaves and fine roots were primarily loaded along the PC1 and PC2 axes of principal component analysis. Suggesting that herbs and shrubs each adopt the most advantageous trait syndrome in accordance with their life form to acquire and conserve resources. The leaf economic spectrum and the root economic spectrum evolved independently, showing no dependence on the variations in life form. In conclusion, in desert plants, leaf and root variations occur independently along two axes, with traits associated with water acquisition playing a neutral role in their ecological strategy.

Interactive effects of rhizobia mutualism and herbivory on Vicia faba

ABSTRACT Background Species constantly interact with many organisms simultaneously, and multiple species interactions can have unique effects when combined and potentially cause resource and fitness trade-offs to the host. For example, extrafloral nectar can be an effective defence against herbivory, yet this nectar production can be influenced by abiotic and biotic environmental factors, including other mutualisms. Aims Here, we tested how traits associated with two different types of species interactions, herbivory and rhizobia-induced nodulation, may independently and interactively affect a host plant. Methods We manipulated the presence or absence of rhizobia at two different levels of herbivory in the field. We measured multiple plant growth traits and fitness responses, such as plant height, above- and below-ground biomass, total biomass, the ratio between above- and below-ground biomass, rhizobia nodule number, and average nodule size, extrafloral nectar volume, extrafloral nectar sugar concentration, as well as ant and arthropod visitation to explore the potential ant-plant mutualism. Results Rhizobia inoculation did not affect ant or other arthropod visitation but did alter plant traits associated with growth as well as decreased allocation to sugar concentration within extrafloral nectar. Extrafloral nectar volume remained nearly constant in nearly all treatments, except for a decrease when plants did not have rhizobia and were not subjected to herbivory. Finally, increased herbivory led to reduced nodule size but did not alter nodule number, indicating potential shifts in resource allocation. Conclusions Overall, multiple species interactions have compounding effects when combined, and plant traits alter differentially in response. In particular, we found a substantial benefit of rhizobia to the plants which did not result in either higher ant visitation or herbivory. However, greater herbivory did reduce plant growth, yet these effects varied depending on the presence or absence of rhizobia. This study demonstrates the importance of considering traits associated with multiple diverse species interactions simultaneously to better understand plant responses to environmental conditions.

CSAIL2019 Crypto-Puzzle Solver Architecture

tThe CSAIL2019 time-lock puzzle is an unsolved cryptographic challenge introduced by Ron Rivest in 2019, replacing the solved LCS35 puzzle. Solving these types of puzzles requires large amounts of intrinsically sequential computations, with each iteration performing a very large (3,072-bit for CSAIL2019) modular multiplication operation. The complexity of each iteration is several times greater than known field-programmable gate array (FPGA) implementations, and the number of iterations has been increased by about 1,000x compared with LCS35. Because of the high complexity of this new puzzle, a number of intermediate, or milestone, versions of the puzzle have been specified. In this article, we present several FPGA architectures for the CSAIL2019 solver, which we implement on a medium-sized Intel Agilex device. We develop a new multi-cycle modular multiplication method, which is flexible and can fit on a wide variety of sizes of current FPGAs. We introduce a class of multi-cycle squarer-based architectures that allow for better resource and area trade-offs. We also demonstrate a new approach for improving the fitting and timing closure of large, chip-filling arithmetic designs. We used the solver to compute the first 23 out of 28 milestone solutions of the puzzle, which are the first reported results for this problem.

Exploring managerial intentions to implement ESG Activities: The role of facilitating conditions in the UTAUT2 framework

This research investigates the factors influencing managers' willingness to adopt Environmental, Social, and Corporate Governance (ESG) practices in small and medium-sized enterprises (SMEs) in Bosnia and Herzegovina. As these practices are becoming increasingly important, it is crucial to understand what factors can increase managers' acceptance of them for both theory and practice. Our analysis was conducted on a sample of 306 managers from Bosnia and Herzegovina. Anchored in the Unified Theory of Acceptance and Use of Technology 2 (UTAUT2), we tested three models to identify predictors of intention to adopt ESG practices and to explore the moderating role of facilitating conditions (FC) on the relationship between performance expectancy and intention to adopt ESG practices. Our findings indicate that there are consistent factors that predict the managers’ intention of adopt ESG practices, including Performance Expectancy (PE), Social Influence (SI), and Habitual Tendency (HT). We found that the FC negatively moderate the link between PE and intention to adopt social and governance practices within ESG framework. We argue that the nature of each domain within ESG, ceiling effect, and resource constraints and trade-offs might be possible explanations for these results.

Constitutive immune function is not associated with fuel stores in spring migrating passerine birds.

Migratory birds may either upregulate their immune system during migration as they might encounter novel pathogens or downregulate their immune system as a consequence of trade-offs with the resource costs of migration. Support for the latter comes not least from a study that reports a positive correlation in autumn migrating birds between fuel stores and parameters of innate and acquired immune function, that is, energy-exhausted migrants appear to have lowered immune function. However, to our knowledge, no study has tested whether this pattern exists in spring migrating birds, which may face other trade-offs than autumn migrants. Here, we investigate if in spring there is a relationship between fuel stores and microbial-killing ability, a measure of innate immune function, and total immunoglobulin (IgY), a measure of acquired immune function, in four migrating bird species: chaffinches (Fringilla coelebs), dunnocks (Prunella modularis), song thrushes (Turdus philomelos) and northern wheatears (Oenanthe oenanthe). Our findings indicate no significant correlation between fuel stores and either microbial killing ability or IgY levels when considering all species collectively. When analysing species separately, we found a significant negative correlation between fuel stores and microbial-killing ability in chaffinches and a positive correlation between fuel stores and IgY levels in wheatears. In song thrushes, but not in any of the other species, there was a significant negative correlation between relative arrival date and microbial-killing ability and between arrival date and IgY levels. Sex did not affect immune function in any of the species. Our study suggests that the relationship between immune function and fuel stores may be different during spring migration compared to autumn migration. Differences in the speed of migration or pathogen pressure may result in different outcomes of the resource trade-off between investment in immune function and migration among the seasons.

Application of resource-environmental-economic perspective for optimal water and nitrogen rate under high-low seedbed cultivation in winter wheat

High-low seedbed cultivation (HLSC), a targeted agricultural method for increasing land utilization efficiency in North China Plain, has emerged as a key practice in enhancing sustainable agriculture, particularly in the context of the region’s unique ecological challenges and water scarcity. However, comprehensive analysis of resource-environment-economy for water and nitrogen strategy in HLSC-cultivated wheat was limited. A three-year field experiment with four nitrogen rates (360, 300, 240, and 180 kg ha−1, denoted as N1, N2, N3, and N4) and three irrigation quotas (120, 90, and 60 mm, referred to as W1, W2, and W3) was conducted to investigate effects of water and nitrogen rate on water productivity (WP), agronomic efficiency of nitrogen (AEN), energy use efficiency (EUE), carbon footprint (CF), water footprint (WF), nitrogen footprint (NF), and net benefits of HLSC-cultivated wheat. Results showed that the total energy output in moderate water and nitrogen input (i.e., N3W2) was 328.0×103 MJ ha−1, which was significantly increased by 31.8% compared with lower input (i.e., N4W3) but was decreased by 17.1% compared with higher input (i.e., N1W1). The total energy input, water consumption and grain yield in N3W2 was decreased by 22.3%, 14.4 and 4.1%, relative to N1W1, respectively, and increased by 18.2%, 20.8% and 42.2% relative to N4W3, respectively. This may lead to significant increase in EUE, WP, AEN and net income in N3W2. Furthermore, the CF, WF, and NF increased as the water and nitrogen input increased, whereas minimum CF, WF and NF per unit of yield was obtained N3/N4 or W1/W2 level. 240 kg N ha−1 coupled with 90–120 mm irrigation quota was recommended by TOPSIS for the HLSC-cultivated wheat to best trade-off resource use efficiencies, environmental footprints, and net benefits. Future studies are needed to further assess the scalability and adaptability of HLSC-cultivated wheat across different climatic zones and soil types.

CRF transcription factors in the trade-off between abiotic stress response and plant developmental processes.

Climate change-induced environmental stress significantly affects crop yield and quality. In response to environmental stressors, plants use defence mechanisms and growth suppression, creating a resource trade-off between the stress response and development. Although stress-responsive genes have been widely engineered to enhance crop stress tolerance, there is still limited understanding of the interplay between stress signalling and plant growth, a research topic that can provide promising targets for crop genetic improvement. This review focuses on Cytokinin Response Factors (CRFs) transcription factor's role in the balance between abiotic stress adaptation and sustained growth. CRFs, known for their involvement in cytokinin signalling and abiotic stress responses, emerge as potential targets for delaying senescence and mitigating yield penalties under abiotic stress conditions. Understanding the molecular mechanisms regulated by CRFs paves the way for decoupling stress responses from growth inhibition, thus allowing the development of crops that can adapt to abiotic stress without compromising development. This review highlights the importance of unravelling CRF-mediated pathways to address the growing need for resilient crops in the face of evolving climatic conditions.

Leaf Traits Explain the Growth Variation and Nitrogen Response of Eucalyptus urophylla × Eucalyptus grandis and Dalbergia odorifera in Mixed Culture.

Mixed cultivation with legumes may alleviate the nitrogen (N) limitation of monoculture Eucalyptus. However, how leaf functional traits respond to N in mixed cultivation with legumes and how they affect tree growth are unclear. Thus, this study investigated the response of leaf functional traits of Eucalyptus urophylla × Eucalyptus grandis (E. urophylla × E. grandis) and Dalbergia odorifera (D. odorifera) to mixed culture and N application, as well as the regulatory pathways of key traits on seedling growth. In this study, a pot-controlled experiment was set up, and seedling growth indicators, leaf physiology, morphological parameters, and N content were collected and analyzed after 180 days of N application treatment. The results indicated that mixed culture improved the N absorption and photosynthetic rate of E. urophylla × E. grandis, further promoting seedling growth but inhibiting the photosynthetic process of D. odorifera, reducing its growth and biomass. Redundancy analysis and path analysis revealed that leaf nitrogen content, pigment content, and photosynthesis-related physiological indicators were the traits most directly related to seedling growth and biomass accumulation, with the net photosynthetic rate explaining 50.9% and 55.8% of the variation in growth indicators for E. urophylla × E. grandis and D. odorifera, respectively. Additionally, leaf morphological traits are related to the trade-off strategy exhibited by E. urophylla × E. grandis and D. odorifera based on N competition. This study demonstrated that physiological traits related to photosynthesis are reliable predictors of N nutrition and tree growth in mixed stands, while leaf morphological traits reflect the resource trade-off strategies of different tree species.

Toward a coordinated understanding of hydro-biogeochemical root functions in tropical forests for application in vegetation models.

Tropical forest root characteristics and resource acquisition strategies are underrepresented in vegetation and global models, hampering the prediction of forest-climate feedbacks for these carbon-rich ecosystems. Lowland tropical forests often have globally unique combinations of high taxonomic and functional biodiversity, rainfall seasonality, and strongly weathered infertile soils, giving rise to distinct patterns in root traits and functions compared with higher latitude ecosystems. We provide a roadmap for integrating recent advances in our understanding of tropical forest belowground function into vegetation models, focusing on water and nutrient acquisition. We offer comparisons of recent advances in empirical and model understanding of root characteristics that represent important functional processes in tropical forests. We focus on: (1) fine-root strategies for soil resource exploration, (2) coupling and trade-offs in fine-root water vs nutrient acquisition, and (3) aboveground-belowground linkages in plant resource acquisition and use. We suggest avenues for representing these extremely diverse plant communities in computationally manageable and ecologically meaningful groups in models for linked aboveground-belowground hydro-nutrient functions. Tropical forests are undergoing warming, shifting rainfall regimes, and exacerbation of soil nutrient scarcity caused by elevated atmospheric CO2. The accurate model representation of tropical forest functions is crucial for understanding the interactions of this biome with the climate.

Consideration of the Environment in Water-Energy-Food Nexus Research in the Aral Sea Basin

The water-energy-food (WEF) nexus is a holistic concept used to understand the synergies and trade-offs of interdependent water, energy, and food resources. Despite its widespread use, this concept often overlooks environmental concerns. In addition, the lack of a systemic approach in the Aral Sea Basin (ASB) has resulted in serious environmental degradation. For instance, the Aral Sea, situated at the terminus of the basin, is steadily shrinking, yet researchers studying the WEF nexus tend to overlook the upstream tributaries of the basin. This study aims to determine the extent to which research on the WEF nexus in the ASB in Central Asia has considered the environment through a systematic review of the literature published between 2012 and 2022. The results indicate that the number of WEF publications regarding the ASB has seen an upward trend, with a primary focus on the transboundary level and less research available on the local and national levels. This confirms the strong reliance of Central Asian states on one another for food, energy, and water resources. Furthermore, the results show that the majority of published studies either do not consider environmental concerns in their analyses at all or do so with little precision. Therefore, to achieve precise and sustainable outcomes, this study recommends the inclusion of environmental concerns along with basin-wide coverage in future WEF analyses. Finally, the WEF concept should be downscaled to the national and local levels in order to facilitate its implementation.

Enhancing Performance of Software Testing Automation using Selenium Web Grid

Web application testing is crucial to ensuring software quality and dependability. Selenium, a popular open-source testing framework, is widely used for automating web browsers to perform various testing tasks. One of the key components of Selenium is Selenium WebGrid, a distributed testing infrastructure that allows running tests in parallel across multiple nodes. This paper presents a comprehensive study on measuring the performance of Selenium WebGrid. The objective is to evaluate its efficiency, scalability, and reliability in executing test scripts across different browsers and operating systems. The study compares the performance of Selenium WebGrid with other testing approaches, such as traditional Selenium Grid and single-node Selenium execution. The methodology employed in this study involves designing a set of representative test cases that simulate real-world scenarios. These test cases cover a range of typical web application functionalities, including form submissions, page navigation, and data validation. The performance metrics considered for evaluation include execution time, resource utilization, and test throughput. To measure the performance of Selenium WebGrid, a testbed environment is set up consisting of multiple nodes with different configurations. The test scenarios are executed on the WebGrid infrastructure, and the performance metrics are collected and analyzed. The results are then compared with those obtained from traditional Selenium Grid and single-node Selenium execution to identify the performance advantages and limitations of Selenium WebGrid. It demonstrates the improved scalability and efficiency of WebGrid in executing tests across multiple nodes simultaneously. The results also provide insights into the resource requirements and trade-offs associated with using Selenium WebGrid compared to other testing approaches. This work adds to the body of knowledge by presenting empirical data on Selenium WebGrid's performance characteristics. It serves as a valuable resource for software testing professionals and researchers interested in leveraging Selenium WebGrid for distributed web application testing.

Enhancing Performance of Software Testing Automation using Selenium web grid

Web application testing is crucial to ensuring software quality and dependability. Selenium, a popular open-source testing framework, is widely used for automating web browsers to perform various testing tasks. One of the key components of Selenium is Selenium WebGrid, a distributed testing infrastructure that allows running tests in parallel across multiple nodes. This paper presents a comprehensive study on measuring the performance of Selenium WebGrid. The objective is to evaluate its efficiency, scalability, and reliability in executing test scripts across different browsers and operating systems. The study compares the performance of Selenium WebGrid with other testing approaches, such as traditional Selenium Grid and single-node Selenium execution. The methodology employed in this study involves designing a set of representative test cases that simulate real-world scenarios. These test cases cover a range of typical web application functionalities, including form submissions, page navigation, and data validation. The performance metrics considered for evaluation include execution time, resource utilization, and test throughput. To measure the performance of Selenium WebGrid, a testbed environment is set up consisting of multiple nodes with different configurations. The test scenarios are executed on the WebGrid infrastructure, and the performance metrics are collected and analyzed. The results are then compared with those obtained from traditional Selenium Grid and single-node Selenium execution to identify the performance advantages and limitations of Selenium WebGrid. It demonstrates the improved scalability and efficiency of WebGrid in executing tests across multiple nodes simultaneously. The results also provide insights into the resource requirements and trade-offs associated with using Selenium WebGrid compared to other testing approaches. This work adds to the body of knowledge by presenting empirical data on Selenium WebGrid's performance characteristics. It serves as a valuable resource for software testing professionals and researchers interested in leveraging Selenium WebGrid for distributed web application testing.

Poor shoot and leaf growth in Huanglongbing-affected sweet orange is associated with increased investment in defenses.

Citrus disease Huanglongbing (HLB) causes sparse (thinner) canopies due to reduced leaf and shoot biomass. Herein, we present results demonstrating the possible mechanisms behind compromised leaf growth of HLB-affected 'Valencia' sweet orange trees by comparing morphological, transcriptome, and phytohormone profiles at different leaf development phases (1. buds at the start of the experiment; 2. buds on day 5; . 3. leaf emergence; 4. leaf expansion; and 5. leaf maturation) to healthy trees. Over a period of 3 months (in greenhouse conditions), HLB-affected trees had ≈40% reduction in growth traits such as tree height, number of shoots per tree, shoot length, internode length, and leaf size compared to healthy trees. In addition, buds from HLB-affected trees lagged by ≈1 week in sprouting as well as leaf growth. Throughout the leaf development, high accumulation of defense hormones, salicylic acid (SA) and abscisic acid (ABA), and low levels of growth-promoting hormone (auxin) were found in HLB-affected trees compared to healthy trees. Concomitantly, HLB-affected trees had upregulated differentially expressed genes (DEGs) encoding SA, ABA, and ethylene-related proteins in comparison to healthy trees. The total number of cells per leaf was lower in HLB-affected trees compared to healthy trees, which suggests that reduced cell division may coincide with low levels of growth-promoting hormones leading to small leaf size. Both bud dieback and leaf drop were higher in HLB-affected trees than in healthy trees, with concomitant upregulated DEGs encoding senescence-related proteins in HLB-affected trees that possibly resulted in accelerated aging and cell death. Taken together, it can be concluded that HLB-affected trees had a higher tradeoff of resources on defense over growth, leading to sparse canopies and a high tree mortality rate with HLB progression.

Trade-off and driving factors of water-energy-food nexus in Mu Us sandy land, China

Water, energy, and food are essential resources for human survival. The trade-off among these resources can limit regional economic development and pose challenges to livelihood security. In this study, we constructed a root-mean-square deviation (RMSD) index to measure the water-energy-food nexus (WEFN) trade-off. Multi-source data and analysis methods, including ordinary least square (OLS), geographically weighted regression (GWR), and geographic detectors (GD) are employed to explore the trade-offs of water, energy, and food resources and their dominant influencing factors in the Mu Us Sandy Land. The results indicate that the trade-off between regional water-food sub-nexus exhibited the highest magnitude, and trade-offs among all sub-nexus types demonstrated significant fluctuations in spatial distribution. Both OLS and GWR results identified temperature, precipitation, normalized differential vegetation index, slope, digital elevation model, and nighttime light as significant factors influencing the spatial differentiation of WEFN trade-offs. Moreover, geographic detector analysis indicated that precipitation is the dominant factor, and its interaction with other influencing factors further impacts the regional WEFN trade-off. The discussion section examines the RMSD method's effectiveness, the dominant factors shaping WEFN trade-offs, as well as scale effect in WEFN trade-offs in the Mu Us area and underscores that mitigation of water shortages can yield a leverage effect, leading to a marked reduction in the trade-offs. This research contributes new ideas and tools to WEFN research from a geographic perspective, aiming to provide guidance for collaborative resource management and regional sustainable development.

Resource nexus perspectives in the Blue Economy of India: The case of sand mining in Kerala

Since the 2000 s the demand for sand has proliferated at the coastal-land interface to fill up the increasing demand straining Blue Economy (BE) activities and provision of water-energy-food resources. Recent studies have revealed that increased sand mining in both coastal and freshwater zones has continued to impact livelihood-ecological systems threatening the provision of livelihood goods and services. These impacts are exacerbated by a lack of comprehensive frameworks to regulate sand mining and trade; creating the need to develop micro and macro-frameworks and guidelines for sustainable sand mining. This paper uses a non-systematic literature review approach to build on this gap to develop an understanding of the resource nexus perspectives and trade-offs due to sand mining. The paper proposes a novel framework based on the Ecosystem Service Assessment advanced from the review of the literature to guide risk assessments toward more sustainable sand mining. In order to add evidence, the paper analyses in-depth the state of Kerala - one of India’s coastal states that has experienced unprecedented rates of sand mining since the 1990 s especially along the Chavara coast albeit with less research on the intersectionality of mining on the resource nexus. Both the framework and our case study highlight how sand mining stresses local ecosystems and livelihoods thus increasing vulnerability to both human and environmental impacts. The paper brings to the fore seven (7) key steps that local institutions can use to guide sustainable sand mining and build integrated governance systems that promote interaction among natural capitals in a given area and livelihood considerations. The article further documents that the use of coherent guidelines and the framework can help in amalgamating the various actors in a given system that can guide local participation in local resource management and the development of cooperative agreements for the sustainable utilization of resources among coastal communities. This could further help understand the resource nexus from the perspective of the synergies and trade-offs in the BE.