Adaptive Management Research Articles

Strategic Management in Digital Media: The Evolution of Innovative Content Creation

Strategic management is now essential in the ever-changing digital media ecosystem to fully use creative content ideas. Focussing on how strategic management has driven innovation, this research study traces the development of content strategies in the digital media business. Successful content production methods are identified by analysing significant trends, technology, and business models in the research. Content creation and delivery have been revolutionised by digital platforms, data analytics, and audience interaction strategies. This study delves into these changes. In order to provide light on best practices and new initiatives, it also analyses case studies of prominent digital media firms. According to the results, companies that want to stay competitive and successfully engage audiences in the digital age need to have a proactive and adaptable strategy management approach. Policymakers, academics, and professionals in the digital media sector may all benefit from this study's findings by better comprehending the factors that drive content creation and strategic management.

Climate change driven by LUCC reduced NPP in the Yellow River Basin, China

Anthropogenic activities and the resulting climate change affect the type, structure, and function of ecosystems. Understanding vegetation dynamics related to anthropogenic activities and climate change is critical to address the terrestrial carbon cycle in the context of global warming. The objective of this study is to quantify the effects of human-induced land use and land cover change (LUCC) and LUCC-induced climate change on terrestrial net primary productivity (NPP) in the Yellow River Basin (YRB) during 2000–2020 using Weather Research and Forecasting (WRF) model and Integrated Biosphere Simulator (IBIS) model through different experimental scenarios. Results indicated that LUCC can cause an increase in NPP of 1.2 ± 0.67 gC m−2 yr−1 in YRB. The increased precipitation and decreased temperature due to LUCC showed weak negative effect on annual mean NPP in YRB (−0.2 ± 0.74 gC m−2 yr−1). The coupling of LUCC and LUCC-induced climate change increased annual mean NPP approximately 0.6 ± 0.86 gC m−2 yr−1. The impacts of LUCC and LUCC-induced climate change and their coupling effects on NPP were greatest in spring, increasing NPP by 5.1 ± 0.51, 3.4 ± 0.41, and 6.1 ± 0.79 gC m−2 yr−1, respectively. These findings provide important guidance for the sustainable and adaptive management of terrestrial ecosystems in river basin in the context of global change.

An adaptive cycle framework for navigating sustainability of oasis socio-ecological system: The case of Hotan region in Xinjiang, China

Assessing the sustainability of socio-ecological system (SES) is the basis for ensuring human well-being and achieving Sustainable Development Goals (SDG) worldwide, especially in arid regions. However, the oasis as a typical socio-ecological system is still lacking a proper approach to examine its evolutionary direction and the sustainability of suitable scale. This study proposes an adaptive cycle framework assessing the sustainability of oasis socio-ecological system to quantify the relationships between the evolution of oasis socio-ecological system and its scale suitability. The framework is constructed by coordination degree, order degree, and oasis suitability metrics of the oasis socio-ecological system to apply in the oases of Tarim basin, Northwest China. The results show that the adaptive cycle evolution of various oases subsystems in study area does not go through four stages successively, but proceeds in a hopping way. The most of them are in the conservation (K) −recognition (α), or recognition (α) − conservation (K) stage. The information entropy of oasis socio-ecological system is inversely proportional to the order degree. The overall oasis information entropy is high ranging from 0.64 to 1.06, but the order degree is at a low level ranging from 0.04 to 0.41. The higher the degree of coordination between subsystems, the higher the degree of oasis suitability. The overall oasis suitability in study area shows a barely appropriate- appropriate-barely appropriate fluctuation state. The main factors affecting the oasis evolution of socio-economic, eco-environment and water resources subsystem are the distribution of industrial structure, green ratio, water consumption per unit grain output, and per capita daily living water consumption, respectively. This study provides support for guiding the sustainable evolution of desert oasis system to adapt to the development scale and the management of oasis socio-ecological system.

Estimating Non-Stationary Extreme-Value Probability Distribution Shifts and Their Parameters Under Climate Change Using L-Moments and L-Moment Ratio Diagrams: A Case Study of Hydrologic Drought in the Goat River Near Creston, British Columbia

Here, we investigate the use of rolling-windowed L-moments (RWLMs) and L-moment ratio diagrams (LMRDs) combined with a Multiple Linear Regression (MLR) machine learning algorithm to model non-stationary low-flow hydrological extremes with the potential to simultaneously understand time-variant shape, scale, location, and probability distribution (PD) shifts under climate change. By employing LMRDs, we analyse changes in PDs and their parameters over time, identifying key environmental predictors such as lagged precipitation for September 5-day low-flows. Our findings indicate a significant relationship between total August precipitation L-moment ratios (LMRs) and September 5-day low-flow LMRs (τ2-Precipitation and τ2-Discharge: R2 = 0.675, p-values < 0.001; τ3-Precipitation and τ3-Discharge: R2 = 0.925, p-value for slope < 0.001, intercept not significant with p = 0.451, assuming α = 0.05 and a 31-year RWLM), which we later refine and use for prediction within our MLR algorithm. The methodology, applied to the Goat River near Creston, British Columbia, aids in understanding the implications of climate change on water resources, particularly for the yaqan nuʔkiy First Nation. We find that future low-flows under climate change will be outside the Natural Range of Variability (NROV) simulated from historical records (assuming a constant PD). This study provides insights that may help in adaptive water management strategies necessary to help preserve Indigenous cultural rights and practices and to help sustain fish and fish habitat into the future.

Recycling the rain: Exploring forest management practices in a western Mediterranean watershed to recouple the atmospheric and terrestrial water cycle

Current knowledge of the role that forests play in recycling rainwater has led to the proposal of forest management practices to mitigate desertification in the western Mediterranean basin. Building upon this hypothesis, we present the Mijares watershed in eastern Spain as a detailed case study. We then perform a scientific literature review in the context of the western Mediterranean basin to identify the physical and biophysical uncertainties associated with forest management practices that aim to strengthen the atmospheric and terrestrial components of the water cycle. The review identified eleven interconnected uncertainties that result from complex vegetation, climate, soil, and water relationships. We discuss the need to deepen our understanding of the atmospheric dynamics of the Mijares by accounting for the role of forests in recycling rainfall and by adopting an adaptive management approach to apply the lessons learned in the territory. Based on these considerations, we propose forest management practices to reinforce the water cycle of the watershed. Our work contributes to understanding the uncertainties arising from forest management practices aimed at mitigating desertification, thereby supporting decision-making. These insights apply to other western Mediterranean coastal watersheds.

Seasonal Variations in Population Dynamics of Insect Pests in Tiruvallur District, Tamil Nadu, India

Understanding the complex relationship between seasonal changes and pest dynamics is essential for establishing effective protection methods in contemporary agriculture and guaranteeing long-term agricultural sustainability and food security. The study was conducted in the Tiruvallur District of Tamil Nadu, India, which is characterized by a tropical climate with distinct wet and dry seasons [1]. Shannon-Wiener Index and Simpson's Index biodiversity indices reflected the moderate to high pest diversity of species in the region. Values for Shannon-Wiener indexes ranged between about 1.93-1.95 for different species of insect pests, and Simpson's indexes were found to range between about 0.85-0.86. All these indices indicate a well-balanced insect pest community with high species richness and even distribution, which is necessary to maintain ecological resilience. The findings enrich our understanding of pest ecology in tropical agriculture and provide valuable insights applicable to other regions facing similar issues. The observed seasonal patterns emphasize the importance of ongoing monitoring and adaptive management to tackle the challenges posed by insect pests amid climate variability and agricultural intensification. Additionally, this research offers a thorough framework for comprehending and managing insect pest populations in the Tiruvallur District.

A geospatial approach to identifying and mapping areas of relative environmental pressure on ecosystem integrity

The influence of increasing anthropogenic pressure on ecosystem integrity, such as land use change, is resulting in many ecosystems experiencing a decline in their ability to maintain balanced functions and services. Identifying and quantifying these pressures over different scales is challenging and thus impacting the achievement or maintenance of key environmental outcomes. In this study, a GIS-based and scalable tool was developed, the Relative Environmental Pressure (REP) Tool, to address these challenges. The REP tool combines an ecosystem integrity conceptual framework with a weighted linear combination analysis to quantify and rank relative environmental pressure across the scale of interest. The REP Tool was developed as an automated Python-based model in a PyCharm working environment using ArcGIS Pro Arcpy scripting. The REP Tool was applied to spatially contiguous geospatial data for the Province of Alberta, Canada and dynamically scaled relative to Hydrologic Unit Codes at level 8 (HUC8) along with regional and sub-regional scale sub-watersheds. Both cumulative and individual relative pressure levels were calculated and mapped for specific ecosystem integrity framework-derived Environmental Pressure Groups (EPGs) including Atmospheric Alteration, Sedimentation, Habitat Alteration, Hydrologic Alteration, and Social Pressure. Data driven Jenks natural breaks were then applied to classify the relative environmental pressures into a nine-level ranking system. The resulting visualization and data outputs from the REP Tool clearly show that the highest cumulative relative environmental pressure values align with the distribution of major population centres, zones of intense agriculture and major industrial activity. These regions reflect the physiography of Alberta with the Rocky Mountain and Boreal natural regions dominated by low relative environmental pressure. As scales become smaller and more refined, the location of the higher relative environmental pressure levels typically become more subdivided with greater spatial precision where higher pressured areas are located. These patterns are repeated when looking at individual EPGs but with enhanced differentiation of pressure as scales are refined. The framework and geospatial science driven approach behind the REP Tool can be universally applied to support enhanced understanding of relative environmental pressures in, or between regions, as well as informing adaptive environmental resource management and monitoring activities.

Adaptive multi-granularity trust management scheme for UAV visual sensor security under adversarial attacks

The big data provided by unmanned aerial vehicle (UAV) visual sensors offers essential information resources for activities across various industries. However, various adversarial threats are inevitable throughout the lifecycle of data generation, transmission, and utilization, leading to serious security risks. Trust assessment of visual sensors is a prerequisite for securing UAVs, but the multidimensionality of the trust elements and the uncertainty of the evidence limit its practical application. To advance this research, we innovatively propose a trust management scheme based on multi-granularity evidence fusion within the framework of belief functions (BFs) theory to adaptively respond to both known and unknown threats. We first propose a direct trust assessment model for known threats, which constructs multidimensional coarse-grained trust elements (MCTEs) and integrates multiple lightweight sub-models for basic belief assignment (BBA) to meet the need for fast response. Then, to address the unknown threats, we introduce pre-trained models to build multidimensional fine-grained trust elements (MFTEs) to construct trust recommendation models for indirect trust assessment for visual sensors. In addition, to accurately characterize the trustworthiness of visual sensors, we also introduce a BBA-weighted fusion method to achieve more reasonable trust aggregation by weakening highly conflicting evidence sources. Finally, to validate the effectiveness of the proposed method, we conducted a comprehensive trust assessment and security experiment on UAV aerial images. The results indicate that the proposed method demonstrates excellent performance and is beneficial for enhancing UAV security in adversarial attack scenarios.

The Performance and Soft Skills: Islamic Higher Education Institutions in Indonesia

The challenge of Higher Education Institutions (HEIs) in Indonesia plays a crucial role and requires enhancement. The pivotal role of HEIs in Indonesia is multifaceted. These institutions play a crucial part in shaping the country's cultural and religious identity, while also providing education that aligns with contemporary demands. This study explored the performance and soft skills among lecturers and administration staff in Islamic HEIs. The study emphasizes performance and soft skills based on managerial effectiveness in Islamic HEIs in Indonesia. The performance and soft skills explored from critical analyses of global literature. The study was conducted in Lombok, Indonesia, among 3 Islamic HEIs. Methods used were literature review, observation, and in-depth interviews. The software used was NVIVO 14 with the relative thematic analysis of the study. Findings on the HEIs model soft skills proposed to address enhancing administration staff performance and lecturer performance. By nurturing these soft skills, organizations thrive when they cultivate alignment, creativity, adaptability, and effective management and avoid mushroom management. Mushroom management in the context of organizational management and leadership styles represents a management style that is characterized by secrecy, lack of transparency, and limited employee involvement in decision-making processes. The results proposed the model to address enhancing administration staff performance through alignment value, change management, and Islamic leadership. The model addresses enhancing lecturer performance through alignment value, change management, Islamic leadership, and divergent thinking. By nurturing these soft skills, organizations thrive when they cultivate alignment, creativity, adaptability, and effective performance management. Administration staff performance impacts the lecturer’s performance besides the lecturer’s performance itself. Research suggests that organizations can benefit greatly from nurturing soft skills and adopting more transparent and inclusive leadership practices to avoid mushroom management. The practical implication of this research proposed model for enhancing administration staff and lecturer performance in Islamic higher education institutions (HEIs) includes administration staff performance enhancement through aligning individual roles with organizational objectives, implementing change management strategies, monitoring performance through key indicators, and applying Islamic leadership principles. Lecturer Performance enhancement through aligning course objectives with institutional goals encouraging research alignment, promoting pedagogical innovations, and fostering visionary leadership.

Spatio-temporal dynamics of net primary productivity and the economic value of Spartina alterniflora in the coastal regions of China

This study employs an improved Carnegie–Ames–Stanford Approach (CASA) model to calculate the Net Primary Productivity (NPP) of Spartina alterniflora (SA) and various other land use/land cover types (LULC) across coastal China over multiple years. The research aims to provide significant theoretical and practical insights into carbon sink research in coastal zones, sustainable development, and resource management. Key findings include identifying the first εmax value of 2.219 g C/MJ for SA, addressing a critical data gap in CASA modeling research on invasive plants. SA's NPP exhibited higher values in Shanghai and Zhejiang due to factors such as genetic diversity, invasion duration, and tidal dynamics. In contrast, other LULC exhibited higher NPP values in southern and inland regions, characterized by greater vegetation cover and favorable growing conditions. In 2020, SA and other LULC sequestered 16.352 kt C and 0.821*106 kt C, respectively. From 2000 to 2020, the average annual NPP and total carbon storage of SA and other LULC increased significantly, primarily driven by Shanghai and deciduous needleleaf forests, respectively. Seasonal NPP trends followed summer> spring> autumn> winter, influenced by climate conditions and plant life activities. Economic assessments in 2020 estimated SA's carbon storage value at RMB0.409 billion (Market Value method) or RMB5.562 billion (Carbon Tax method), with RMB2.054 billion attributed to oxygen release values, underscoring its economic and ecological potential. Among other LULC, evergreen broadleaf forests showed the highest carbon storage value (RMB183.463 billion). The study emphasizes the critical role of all LULC in carbon storage and oxygen release, advocating for targeted conservation and land management strategies. It suggests that managing SA should balance stringent control in high-risk areas, lenient measures in low-risk areas, eradication of scattered populations, and maximizing ecological benefits in retention areas, with continuous monitoring and adaptive management strategies to balance conservation and development efforts.

An Approach of Integration of Contextual Data in E-Service System for Management of Multimodal Cargo Transportation

Our research area concerns the development of an intelligent e-service system to help manage multimodal transportation processes. To better respond to the requirements of sustainable development, we encourage the development of multimodal cargo transportation. Therefore, it is important to ensure that the dissemination and management of information in multimodal transportation requires more accurate information transmission and implementation for better coordination of these processes with the interaction of all process participants. Also, contextual data integration into the e-service provision processes is important for more adequate real cargo transportation management. The transition to multimodal freight transport and the increase in its activity directly impact the sustainable development of this sector as transport flows are removed from ground roads and distributed more evenly to load more railways and sea vessels. This research aims to develop an approach to developing the infrastructure of an e-service system with the ability to integrate contextual data and influence the management of multimodal transportation. The methodological approach is based on methods of conceptual representation of information and methods for recognizing the flow of needful information during multimodal freight transportation according to adaptable management processes. The e-service provision system creates benefits for cargo drivers and delivery managers with more accurate information implementation and more adequate coordination of processes under real conditions by helping them make the right decisions.

International wildlife trade quotas are characterized by high compliance and coverage but insufficient adaptive management

Effective management of international wildlife trade is crucial to ensure sustainability. Quotas are a common trade management tool and specify an annual number of individuals to be exported, yet at present there is no global assessment of quota coverage and compliance. Using over 7,000 country–year specific reptile quotas established under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) covering 343 species, we quantify quota coverage, compliance, trade trends pre-quota and post-quota setting and whether quotas likely represent adaptive management. Quotas predominantly concerned live wild-sourced reptiles, with only 6.6% of live non-zero quotas exceeded and 4.5% of zero quotas subverted. For 62.3% of species, quotas were established higher than pre-quota trade, with traded volumes post-quota mainly unchanged or higher than pre-quota establishment, thus potentially facilitating sustainable trade. Over 38% of quota series of species remained at the same level each year, with the longest-running quotas proportionately updated the least, indicating that many quotas do not change adaptively in response to changing threats to species through time. Greater specificity in exactly what quotas cover, justification for unchanged quotas and transparency over quota determination are needed to ensure that high compliance equates to sustainable use.

Perspectives of integrated climate change and water policies in Hungary

The paper aims to outline the climate impacts induced and transferred by water and the socio-economic factors that exacerbate them. It also seeks to provide a common and integrated policy framework for climate change adaptation and water management. The climatic and non-climate drivers, the risk chains and options for policy integration are assessed in four complex thematic areas: (i) ecosystem services, (ii) food supply chain: agriculture, food processing industry, food safety; (iii) industrial and service activities, energy and water supply, infrastructure, built environment, and (iv) human health and well-being, social justice. In these complex thematic areas, we examine the risk cascade chain, the current state of impacts and expected future challenges within a coherent framework and then make concrete proposals for possible specific areas of policy integration. Finally, in the conclusions, we present municipal-level good practices in water-resilient climate adaptation and formulate the horizontal actions needed to implement integrated climate-water policy.

Climate winners: Adapting to shifting species in the New England supply chain

AbstractObjectiveClimate change is driving shifts in marine species' distributions, affecting resource availability for fishery supply chains worldwide. While research and governance have been in step with fishing impacts, consequences to the downstream supply chain are not generally considered. In this project, we identify how and to what extent New England seafood supply chains are capable of navigating anticipated shifts in species distributions. The study was especially concerned with the degree to which suppliers would consider incorporating "climate winners": species that are predicted to become more abundant in New England waters.MethodsUsing indicators derived from climate resilience and adaptive fisheries frameworks, we characterized supply chain adaptability for 27 seafood businesses across New England.ResultThe results revealed a range of adaptability linked to particular supplier characteristics, including diversity of services, processing infrastructure, and market diversity. External factors such as consumer preference, regulatory policy, and employment in the industry also indicated climate vulnerabilities. Despite these limiting factors, however, most businesses appeared to be not only capable but also willing to incorporate climate winner species into their portfolio.ConclusionOur conclusions support the idea that New England seafood suppliers adopt different strategies for climate resilience based on their business model, with considerable potential to take advantage of species shifts given the right incentives. To reduce vulnerabilities in the face of unprecedented change, it is critical that managing practitioners and partnering organizations encourage portfolio diversification with market incentives and adaptive management measures.

A practical approach to meeting national obligations for sustainable trade under CITES.

Reconciling conservation goals with sustainable resource use requires adaptive management strategies. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) regulates global trade for species listed on Appendix II, partly by requiring member countries (parties) to ensure exports do not damage wild populations (called making positive "nondetriment findings" [NDFs]). Unfortunately, when parties find NDFs difficult, they often suspend legal trade, imposing economic costs and driving trade underground. To make it easier for parties to examine the detrimental nature of exports, we devised a spatial approach and applied it to seahorses (Hippocampus spp.) in Tamil Nadu, India, as an example. Our approach involves mapping answers to 5 key questions on species distribution (QA), pressures (QB), management measures (QC), management implementation (QD), and species' population status (QE). We gathered data from fisher interviews and published literature. Seahorse abundance was greatest in southern Palk Bay and the northern Gulf of Mannar, primarily in seagrasses and coral reefs (QA). Fishing pressure was highest in Palk Bay, primarily from bottom trawlers and dragnetters operating in shallow seahorse habitats near the coastline (QB). Management measures including a marine protected area (MPA), bottom trawl exclusion zone, and closed season were theoretically in place (QC), but their implementation was poor (QD). Fishers reported seahorse catches in 85% of the area covered by the MPA and the exclusion zone; bottom trawlers were responsible for most violations. Seahorses were also captured in Sri Lankan waters, where bottom trawling is banned. Fisher reports indicated declining seahorse catches and reduced body sizes (QE), highlighting unsustainable exploitation. Our results highlight the need for better implementation of existing management measures before a positive NDF can be made and suggest mitigation beyond bans. Such pragmatic spatial analyses can help regulate exports at sustainable levels, supporting CITES implementation for its vast range of species.

Assessing Larix principis-rupprechtii productivity and its determinants based on national forest inventory data in Hebei Province, China

Tree productivity is not only determined by stand structure, but also influenced by soil chemical properties, climate and topography. However, the relative importance of each indicator on larch (Larix principis-rupprechtii) productivity were uncertain. In this study, 76 pure larch forest plots were selected based on national forest inventory (NFI) data in Hebei Province, China. Structural equation model (SEM) was used to analyze the direct and indirect effects of stand structure, soil chemical properties, climate and topography on larch productivity, and to quantify the relative importance of each indicator in determining productivity. The results showed that stem volume growth (SVG) of larch was influenced by a combination of stand density, diameter at breast height (DBH), mean winter snow (PAS), annual temperature range (TD), slope, and alkali-hydrolysis nitrogen (AN). SVG tended to increase with decreasing stand density and AN content and increasing DBH. Stand density, DBH and AN were more important than PAS, TD, and slope in explaining SVG variation. The results can provide a scientific basis for adaptive management of larch forests.

Leveraging deep learning and computer vision technologies to enhance management of coastal fisheries in the Pacific region

This paper presents the design and development of a coastal fisheries monitoring system that harnesses artificial intelligence technologies. Application of the system across the Pacific region promises to revolutionize coastal fisheries management. The program is built on a centralized, cloud-based monitoring system to automate data extraction and analysis processes. The system leverages YoloV4, OpenCV, and ResNet101 to extract information from images of fish and invertebrates collected as part of in-country monitoring programs overseen by national fisheries authorities. As of December 2023, the system has facilitated automated identification of over six hundred nearshore finfish species, and automated length and weight measurements of more than 80,000 specimens across the Pacific. The system integrates other key fisheries monitoring data such as catch rates, fishing locations and habitats, volumes, pricing, and market characteristics. The collection of these metrics supports much needed rapid fishery assessments. The system’s co-development with national fisheries authorities and the geographic extent of its application enables capacity development and broader local inclusion of fishing communities in fisheries management. In doing so, the system empowers fishers to work with fisheries authorities to enable data-informed decision-making for more effective adaptive fisheries management. The system overcomes historically entrenched technical and financial barriers in fisheries management in many Pacific island communities.

Birdwatching preferences reveal synergies and tradeoffs among recreation, carbon, and fisheries ecosystem services in Pacific Northwest estuaries, USA

Coastal ecosystems provide multiple ecosystem services that are valued in diverse ways. The Nisqually River Delta (the Delta), an estuary in Puget Sound, Washington, U.S.A., is co-managed by the Nisqually Indian Tribe and the Billy Frank Jr. Nisqually National Wildlife Refuge. In an ecosystem services assessment, we used different service-appropriate methods including citizen science, statistical and geospatial models, and scenario analysis to evaluate three ecosystem services – recreational birdwatching, soil carbon accumulation and fishery production – indicated as priorities for the Refuge, Nisqually Indian Tribe, and surrounding communities. We developed a generalized additive mixed model set based on eBird mobile application birdwatching observations to understand the biological and landscape features that influence birdwatching and to project birdwatching visitation based on scenarios of Delta habitat change. We evaluated ecosystem service synergies and tradeoffs associated with habitat change for three coastal habitat types using scenario outputs from the birdwatching model and published results on Delta soil carbon accumulation and fishery production. The highest-ranked birdwatching models explained 88 % of the deviance and showed that visitation was greatest in winter months when distance to major cities was approximately 20 km. Recreational birdwatching increased with increasing area of forested wetland, emergent wetland, aquatic vegetation bed, open access, and total estuary. With increasing forested and emergent wetland area, recreational birdwatching, out-migrating juvenile Chinook salmon weight and soil carbon accumulation all increased. With increasing aquatic vegetation bed (resulting from sea level rise), recreational birdwatching increased, but salmon weight and soil carbon accumulation decreased. We identified practical ways in which ecosystem services may be incorporated into adaptive management frameworks that support climate adaptation decision making. This study illustrated how use of ecosystem services can help managers make decisions that have greater benefit for wildlife and people, communicate the societal value of decisions and increase local support and participation.

Unsteady vane-rotor secondary flow interaction of the endwall region in a 1.5-stage variable-geometry turbine

Variable-geometry turbines present significant improvements in both off-design cycle efficiency and enhanced engine responsiveness for future adaptive cycle engines. The adjustable vanes regulate the through-flow capacity by varying the installation angle and thus unavoidably require endwall clearance, resulting in profound implications for vane and downstream blade rows. Unsteady numerical simulations are carried out to investigate the vane-rotor flow interaction under the zero and partial clearance type of the adjustable vane in a 1.5-stage variable-geometry turbine. First, specific vortical structures and loss characteristics of upstream adjustable vane leakage flow at turning angles of −5°, 0°, and +5° are described. Then, the basic mechanisms of vane-rotor secondary flow interaction between acquired upstream leakage flow and downstream blade rows secondary flow is explored by the time-resolved method and quantitative detailed analysis method. The results show that adjustable vane vortex core area is the primary cause of internal loss within the vortex, and the mixing and interaction between the leakage vortex and other vortex systems contribute to secondary loss in the vane. Due to the downstream blade shear action caused by different flow velocity on the suction and pressure surfaces, the vane leakage flow fragments upon entering the R1 blade passage and develops downstream of the endwall region. Compared to the vane with zero clearance case at same turning angle, the intensity of the R1 tip leakage vortex at the design turning angle and open turning angle is reduced by 47.4 % and 23.66 % with the upstream partial clearance, respectively. The unsteady vane-rotor secondary flow interaction under different turning angles has large influence on the flow structure and loss characteristics of the downstream blade rows, and results in significant differences in the variation pattern and trend direction of the turbine performance.

An opinion on adaptive governance and management in water resources restoration projects

This opinion article presents arguments to sustain the inclusion of local actors in the governance and management of water resource restoration projects. There is a lack of knowledge regarding this issue, and we propose that governance and management must be adaptive because of the complexity and constant modification of the local systems. Our proposal has theoretical, methodological, and management impacts on the network governance of local projects. We present a matrix of variables to facilitate research and management plans.