Conceptual Ecological Model Research Articles

The use of conceptual ecological models to identify critical data and uncertainties to support numerical modeling: The northern Gulf of Mexico eastern oyster Crassostrea virginica example

AbstractObjectiveIncreasing reliance on numerical simulation models to help inform management and restoration choices benefits from careful consideration of critical early steps in model development. Along the northern coast of the Gulf of Mexico, the eastern oyster Crassostrea virginica fulfills important ecological and economic roles. Using the eastern oyster as an example, we draw on several recent frameworks outlining best practices for model development and application for restoration, conservation, and management.MethodsWe identify priority model questions, outline a conceptual ecological model (CEM) to guide numerical model development, and use this framework to identify uncertainties and research needs.ResultThe CEM uses a nested design, identifying explicit vital rates, processes, attributes, and outcomes for the species (oysters), population, and metapopulation (i.e., network of populations) levels in response to drivers of species, population, and metapopulation changes and changing environmental factors. Most management actions related to oyster restoration and harvest affect population attributes directly, but many coastal management actions and changes (i.e., climate change and coastal and water resource engineering) impact environmental factors that alter vital rates and attributes of oysters, populations, and metapopulations.ConclusionInvestment in studies targeting individual oyster‐ and population‐level multi‐stressor responses (filtration, respiration, growth, and reproduction) and improving hydrodynamic and environmental models targeting drivers that influence metapopulation vital rates and attributes (i.e., connectivity and substrate persistence) would contribute to reducing uncertainties. Development of numerical models covering the entire oyster life cycle and connectivity of populations using hydrodynamic models of current and predicted conditions to provide key abiotic and biotic factors influencing larval movement, recruitment, and on‐reef oyster vital rates would assist in balancing the goals of conservation, restoration, and fisheries management of this foundational estuarine species.

Stimulation of Aquatic Bacteria from Mammoth Cave, Kentucky, by Sublethal Concentrations of Antibiotics

Many microorganisms secrete secondary metabolites with antibiotic properties; however, there is debate whether the secretions evolved as a means to gain a competitive edge or as a chemical signal to coordinate community growth. The objective of this research was to investigate if select antibiotics acted as a weapon or as a chemical signal by exposing communities of aquatic cave bacteria to increasing concentrations of antibiotics. Water samples were collected from six cave locations where actinobacterial mats appeared to be plentiful. Bacterial growth was measured using colony counts on 10 % tryptic soy agar augmented with increasing concentrations of erythromycin, tetracycline, kanamycin, gentamicin, or quaternary ammonia compounds (QAC). Colony counts generally decreased as the gentamicin, kanamycin and QAC dose increased. In contrast, the colony numbers increased on agar plates supplemented with 0.01 mg L−1, 0.10 mg L−1 and 1.00 mg L−1 erythromycin or tetracycline. A 10.00 mg L−1 dose of each antibiotic treatment reduced bacteria colonies by 98 % or more. Community-level physiological capabilities were evaluated using Ecolog plates inoculated with cave water dosed with either 0.00 mg L−1 or 0.10 mg L−1 of erythromycin. Incubation with the antibiotic almost doubled the number of food substrates used in the first 24 hours. There was a significant increase in the use of acetyl glucosamine, arginine, and putrescine when bacteria were exposed to 0.10 mg L−1 erythromycin triggered by the antibiotic acting as a chemical messenger. Principal component analysis confirmed a shift in substrate preferences when erythromycin was added. A conceptual ecological model is proposed based on the response of aquatic cave bacteria to sublethal antibiotics.

Preliminary Effectiveness of a Strategy to Promote Healthy Lifestyle Habits in Schoolchildren.

Purpose: To measure the preliminary effectiveness of a strategy to promote healthy lifestyle habits in schoolchildren, aged 6 to 12 years, living in the Andean region of Colombia, 2018–2021. Design and Methods: This is a Nursing Methodological Research, developed in phases: (1) Context and schoolchildren characterization; (2) Strategy design guided by the Whittemore and Grey criteria and the Bronfenbrenner ecological conceptual model; (3) Strategy validation with 11 experts; (4) Trial to evaluate preliminary effectiveness. We applied the strategy in seven different schools with the educational community including 955 schoolchildren between 6 and 12 years of age, 551 parents, 130 teachers and 7 members of the food staff. Results: Our health promotion strategy “Prosalud” has five components: citizenship feeding and nutrition, physical activity, and rest; environment protection, and directing one’s own life. It includes all the participants of the educational community. Conclusions: According to experts, the health promotion strategy “Prosalud” is valid to help promoting healthy lifestyle habits among schoolchildren. This strategy demonstrates its preliminary effectiveness in a group of school children from 6 to 12 years of age, their parents, teachers, and school food staff, in the Andean region of Colombia.

Desulfuromonas sp. 'CSMB_57', isolation and genomic insights from the most abundant bacterial taxon in eastern Australian coals.

One of the most abundant and ubiquitous taxa observed in eastern Australian coal seams is an uncultured Desulfuromonas species and part of the Coal Seam Microbiome dataset assigned as ‘CSMB_57’. Despite this abundance and ubiquity, knowledge about this taxon is limited. The present study aimed to generate an enrichment culture of Desulfuromonas sp. ‘CSMB_57’ using culturing strategies that exploit its sulphur-reducing capabilities by utilizing a polysulfide solution in a liquid medium. Using dilution to extinction methods, a highly enriched culture was successfully generated. The full-length 16S rRNA sequence revealed that all closely related taxa were observed in subsurface environments suggesting that D. sp. ‘CSMB_57’ may be a subsurface specialist. Subsequently, the DNA from the enrichment culture was sequenced and the genome of D. sp. ‘CSMB_57’ was assembled. Genomic annotation revealed a high number of CRISPR arrays for viral defence, a large array of ABC transporters for amino acid and peptide uptake, as well as genes likely associated with syntrophy such as genes associated with type-IVa pilus, often used for direct interspecies electron transfer, and multiple hydrogenases capable of producing hydrogen. From the various genomic observations, a conceptual ecological model was developed that explores its possible syntrophic roles with hydrogenotrophic methanogens and acetogenic bacteria within coal-seam environments.

The Experiences and Needs of Families of Comatose Patients After Cardiac Arrest and Severe Neurotrauma: The Perspectives of National Key Stakeholders During a National Institutes of Health-Funded Workshop.

OBJECTIVES:Severe acute brain injury (SABI) from cardiac arrest and traumatic brain injury happens suddenly and unexpectedly, carrying high potential for lifelong disability with substantial prognostic uncertainty. Comprehensive assessments of family experiences and support needs after SABI are lacking. Our objective is to elicit “on-the-ground” perspectives about the experiences and needs of families of patients with SABI.DESIGN:Two-phase qualitative study of families and multidisciplinary U.S. healthcare professionals (mHCPs) with expertise in SABI: Phase 1 included semistructured interviews to generate formative findings; phase 2 entailed facilitated discussions to confirm and expand initial findings.SETTING:Phase 1: academic medical center; phase 2: virtual workshop.SUBJECTS:Phase 1 included seven family members and 12 mHCPs. Phase 2 included nationally recruited stakeholders (17 family members and 12 mHCPs).INTERVENTION:None.MEASUREMENTS AND RESULTS:We explored: 1) what are families’ needs in the first 48 hours? 2) How are these needs addressed? and 3) How can hospitals better meet these needs? Qualitative analysis included inductive and deductive approaches guided by a conceptual ecological model. Four major needs were identified: 1) challenges in coping with uncertainty in early prognostication, 2) inattention to physical needs of family, 3) deficits in compassionate and consistent communication, and 4) need for engagement with families as stakeholders in improving future practices. Participants’ recommendations included: 1) ways to communicate more clearly and consistently, 2) better assistance with navigating resources and access to places for families to care for themselves, and 3) opportunities for families to remain connected with their loved ones, social support networks, and the clinical team.CONCLUSIONS:Stakeholders identified novel insights regarding families’ experiences during the hospitalization of comatose SABI patients and factors that can contribute to improved decision-making and physical/emotional outcomes. Interventions to address these unmet needs are promising targets to improve outcomes.

Mapping the Extent of Mangrove Ecosystem Degradation by Integrating an Ecological Conceptual Model with Satellite Data

Anthropogenic and natural disturbances can cause degradation of ecosystems, reducing their capacity to sustain biodiversity and provide ecosystem services. Understanding the extent of ecosystem degradation is critical for estimating risks to ecosystems, yet there are few existing methods to map degradation at the ecosystem scale and none using freely available satellite data for mangrove ecosystems. In this study, we developed a quantitative classification model of mangrove ecosystem degradation using freely available earth observation data. Crucially, a conceptual model of mangrove ecosystem degradation was established to identify suitable remote sensing variables that support the quantitative classification model, bridging the gap between satellite-derived variables and ecosystem degradation with explicit ecological links. We applied our degradation model to two case-studies, the mangroves of Rakhine State, Myanmar, which are severely threatened by anthropogenic disturbances, and Shark River within the Everglades National Park, USA, which is periodically disturbed by severe tropical storms. Our model suggested that 40% (597 km2) of the extent of mangroves in Rakhine showed evidence of degradation. In the Everglades, the model suggested that the extent of degraded mangrove forest increased from 5.1% to 97.4% following the Category 4 Hurricane Irma in 2017. Quantitative accuracy assessments indicated the model achieved overall accuracies of 77.6% and 79.1% for the Rakhine and the Everglades, respectively. We highlight that using an ecological conceptual model as the basis for building quantitative classification models to estimate the extent of ecosystem degradation ensures the ecological relevance of the classification models. Our developed method enables researchers to move beyond only mapping ecosystem distribution to condition and degradation as well. These results can help support ecosystem risk assessments, natural capital accounting, and restoration planning and provide quantitative estimates of ecosystem degradation for new global biodiversity targets.

Dual perspectives in autism spectrum disorders and employment: Toward a better fit in the workplace.

Compared with people with other disabilities, individuals with autism spectrum disorder (ASD) have the lowest rates of employment and switch jobs at a higher frequency. Thus, understanding how to support workplace success for people with ASD is important. Grounded in an ecological conceptual model, this study explores the dual employment perspectives of adults with ASD and supervisors who worked with individuals with ASD. Using participatory research methods, a purposive sample of ten adults with ASD (all verbal with high school diplomas) and ten supervisors participated in semi-structured interviews on employment experiences. Qualitative analyses were used to identify themes. Four major themes emerged from an ecological framework to create a strong person-environment fit in the workplace: 1) building on interest/experiences/strengths/skills, 2) reducing social demands, 3) clear communication and expectations, and 4) ASD awareness for work environment. Comparisons between the two groups of participants showed substantive differences in expectations and accommodations. Supervisors, although eager to employ individuals with ASD, could benefit by employing an ecological model to successful employment. Results indicate that multiple lenses on the process of employment for those with ASD can lead to better outcomes in the workplace.

Growing Older in Social Work: Perspective on Systems of Support to Extend Working Lives—Findings from a UK Survey

AbstractSocial work, like many other human service professions, is ageing. This article reports and discusses the findings of a UK social work survey undertaken in 2018 (1,397 responses). It investigated how organisational policies and individual factors were affecting individual social workers’ decisions about working in later life. The survey measured (i) social workers’ attitudes to ageing at work and self-reported planning around retirement; (ii) mental health and well-being, quality of working life and home and work interface and (iii) intention to leave work and retirement planning. Statistical analysis enabled examination of how the interrelationship of these factors and relevant individual characteristics interact within the systemic work environment. Findings revealed that all participants had considered factors that might cause them to retire early. Framing the findings in an ecological conceptual model suggests that age-inclusive professional and organisational cultures, age-positive human resource management, support from line managers, fair working conditions and the ability to manage health and well-being, might enable social workers to extend their working lives in line with government policy. These findings provide insights for social work workforce policymakers and for employers to assist in their development of organisational and individual adjustments to sustain well-being in the social work profession.

Physical assault perpetration and victimisation among Chinese university students

ABSTRACTThis study applies the ecological conceptual model in examining the rates and risk factors of both severe and minor physical assault perpetration and victimisation among university students in Hong Kong, Taiwan and Mainland China. Data were from the International Dating Violence Study. The analysis employed a generalised mixed effect model. Findings showed the rates of minor physical assault perpetration was 34.1% among the participants; minor victimisation was 16.2%; severe perpetration was 23.9%; and, severe physical assault victimisation was 12.5%. Female students were more likely to report minor and severe physical assault perpetration compared to males [aOR = 2.48 (1.80, 3.43), and 2.89 (1.83, 4.56), respectively, p values<0.05]. Controlling for all variables, if sexual relations were part of the dating relationship, the odds of minor and severe violence perpetration and victimisation were 1.98 and 2.23 (p values<0.05). Good anger management was associated with a 60 to 70% decrease in the odds of physical assault.

Application of a Conceptual Ecological Model to Predict the Effects of Sand Mining around Chilsan Island Group in the West Coast of Korea

Chilsan Island Group, located on the west coast of South Korea, has been recognized as a critical breeding and nursery ground for endangered seabirds because food is abundant and human activity is low. Chilsan Island Group has been under protection as a Natural Monument (Article no. 389) since 1997, but attempts were made in 2004 to exploit the coastal sands around the islands. A conceptual ecological model (CEM) was employed with energy flow diagram (EFD) to predict the effects of sand mining on the islands’ ecosystem. The results showed that sand mining activities caused long-term damage to benthic ecosystems and threatened seabird communities by reducing fish populations throughout the food web. The changes in energy flow in the ecosystem due to sand mining operations predict that reduction in secondary production of benthic animal communities might reduce energy transfer to humans and seabirds by 30%. Different ranges of uncertainty provided by the Monte Carlo simulation lead to the conclusion that sand mining could bring about undesirable consequences. One concern is that such negative consequences would have a much more severe impact on seabirds than humans because seabirds cannot compete effectively against humans for the limited food sources. In this study, the complex interrelationships between ecosystem members were simplified and a CEM was established to clearly identify which elements would be affected. The CEM with EFD was found to be helpful in promoting communication between stakeholders, and it is expected to be widely used as a decisionmaking tool by public officials.

Projecting the effects of climate change and water management on Devils Hole pupfish (Cyprinodon diabolis) survival

AbstractAquatic ecosystems of North American deserts are frequently very restricted in area and tend to harbour very specialized species endemic to their restricted habitats. Small changes in environmental conditions of these specialized forms may jeopardize their persistence. A notable example of endemic and specialized species that may have been influenced by slight changes in its habitat is the Devils Hole pupfish (Cyprinodon diabolis), which occurs only in a small pool ecosystem in the Mojave Desert of the Southwestern United States. In this study, we use a computational fluid dynamic (CFD) model to examine the physical effects of climate change and local groundwater management on Devils Hole and combine those results with a conceptual ecological model to consider the impacts of those changes on annual recruitment of C. diabolis. The CFD model predicts water temperatures as a response to climate and water level, and the ecological model is used to determine the timing of tipping points that may encourage or suppress the annual recruitment of C. diabolis. The combination of interdisciplinary modelling approaches offers a method to quantify and compare the suitability of habitat under a range of management and climate scenarios. Our results show that the influence of water level on peak temperatures in Devils Hole (and on the ecosystem's suitability for C. diabolis) is an order of magnitude greater than the influence of climate change. Copyright © 2015 John Wiley &amp; Sons, Ltd.

基于生态流方法的土地整治项目对农田生态系统影响研究

PDF HTML阅读 XML下载 导出引用 引用提醒 基于生态流方法的土地整治项目对农田生态系统的影响研究 DOI: 10.5846/stxb201405110964 作者: 作者单位: 南京大学地理与海洋科学学院 江苏 南京 210023,南京大学地理与海洋科学学院 江苏 南京 210023,南京大学地理与海洋科学学院 江苏 南京 210023,南京大学地理与海洋科学学院 江苏 南京 210023,南京大学地理与海洋科学学院 江苏 南京 210023 作者简介: 通讯作者: 中图分类号: 基金项目: 教育部博士点基金(20120091110014);国家自然科学基金(41201386);江苏省普通高校研究生科研创新计划资助项目(CXZZ13_0046) Determining the effect of the land consolidation project on the cropland ecosystem based on the ecological flow method Author: Affiliation: School of Geographic and Oceanographic Sciences, Nanjing University,School of Geographic and Oceanographic Sciences, Nanjing University,School of Geographic and Oceanographic Sciences, Nanjing University,School of Geographic and Oceanographic Sciences, Nanjing University,School of Geographic and Oceanographic Sciences, Nanjing University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:将土地整治活动作为外界对农田生态系统(项目区)集中性的外部激励,以陕西关中凤翔县典型土地整治项目为例,分析了项目实施前后生态流(物质流、能量流、信息流)变化状况,建立了土地整治生态影响概念性模型,明确了相应生态流的流向与路径关系,使用可用能法和能值法测算项目区外部输入及生态产品输出,应用生态流分析法,对土地整治项目生态流和系统效率进行了定量计算。根据设定的土地整治工程使用年限,评估了项目实施后区域净生态价值、自然资源依赖度、可更新资源依赖度、生态产出率、生态承载力和生态可持续度等指标的时间变化过程。得到以下研究结果:(1)可用能法和能值法测算出的系统生态效益均呈现由项目建设初期陡降为负值,而后指数增加,再趋于平稳的过程;(2)可用能法测算出项目实施后的第29年,生态效益由亏转盈,体现出系统从被扰乱后恢复自然平衡状态的过程;(3)能值法测算出项目实施后的第4年,生态系统趋于平衡状态;(4)研究区土地整治项目的经济效益为负,于项目实施3a后趋于平稳,总投资中农业生产年投入占资金总额的78.35%。通过可用能和能值方法的结合,可以定量计算系统稳定性,为土地整治项目的物质、劳动力和资金投资选择等提供借鉴。 Abstract:Ecological flows reflect the relationships among metabolism, energy conversion, information exchange, and so forth. A quantitative analysis of the development of ecological flow patterns of various parameters was performed. Based on existing exergy accounting, ecological flow networks in a typical semi-natural cropland ecosystem were analyzed, with five ecological indicators being used to evaluate the ecological effectiveness of these networks. Exergy buffers the capacity and environmental impact on cropland ecosystems. Previous studies have examined exergy effectiveness in a variety of fields, but exergy analysis has rarely been applied to assess cropland ecosystems. Research time is significant because ecosystem stability varies in different periods;hence, ecological flow results will differ. In the cropland ecosystem used for this study, we chose the time period from planting to harvest to determine eco-flows based on the life-cycle theory, and set the land consolidation project edge as the boundary. This study only considered crop growth and the impacts of human-assisted primary production. As a sudden short-term external incentive of the project cropland ecosystem area, land consolidation activities influenced ecological flow changes after land consolidation project implementation (LCPI), which included material, energy, and information flow changes. A land consolidation ecological conceptual model was built and reflected ecological flow direction and path. It used exergy and emergy accounting methods to study the external input, output, and ecological products. The study used a land consolidation project in Fengxiang County of Shaanxi Province as a case study, and applied ecological flow analysis to it to determine the intensity of ecological flow and system efficiency. Using different land consolidation project terms, this study evaluated net ecological value, natural resource dependency, renewability dependency, ecosystem productivity, ecological capacity, and ecological sustainability after LCPI. The exergy and emergy accounting methods presentedchanges to the ecological benefits process as a steep negative decline at the preliminary stage, followed by an exponential increase, and finally leveled off. Second, the exergy accounting method traced the ecological benefit losses and profit over the 29 years after LCPI in the study area was initiated, and manifested the system process recovery from chaos to natural balance. Third, the emergy accounting method demonstrated that, in the fourth year after LCPI, the ecosystem tended toward a state of relative balance, with an increase in ecological productivity and potential investment demands. Fourth, the economic benefits of the land consolidation project were negative and leveled off after 3 years, reflecting an annual agricultural production investment of 78.35%. Through the combination of exergy and emergy, the system stability was quantified and calculated. This study can be used as a reference for deciding input material, labor, capital, etc. for use in future land consolidation project planning. 参考文献 相似文献 引证文献

Isothermal Microcalorimetry Provides New Insight into Terrestrial Carbon Cycling

Energy is continuously transformed in environmental systems through the metabolic activities of living organisms, but little is known about the relationship between the two. In this study, we tested the hypothesis that microbial energetics are controlled by microbial community composition in terrestrial ecosystems. We determined the functional diversity profiles of the soil biota (i.e., multiple substrate-induced respiration and microbial energetics) in soils from an arable ecosystem with contrasting long-term management regimes (54 years). These two functional profiling methods were then related to the soils' microbial community composition. Using isothermal microcalorimetry, we show that direct measures of energetics provide a functional link between energy flows and the composition of below-ground microbial communities at a high taxonomic level (Mantel R = 0.4602, P = 0.006). In contrast, this link was not apparent when carbon dioxide (CO2) was used as an aggregate measure of microbial metabolism (Mantel R = 0.2291, P = 0.11). Our work advocates that the microbial energetics approach provides complementary information to soil respiration for investigating the involvement of microbial communities in below-ground carbon dynamics. Empirical data of our proposed microbial energetics approach can feed into carbon-climate based ecosystem feedback modeling with the suggested conceptual ecological model as a base.

Integrated conceptual ecological model and habitat indices for the southwest Florida coastal wetlands

The coastal wetlands of southwest Florida that extend from Charlotte Harbor south to Cape Sable, contain more than 60,000ha of mangroves and 22,177ha of salt marsh. These coastal wetlands form a transition zone between the freshwater and marine environments of the South Florida Coastal Marine Ecosystem (SFCME). The coastal wetlands provide diverse ecosystem services that are valued by society and thus are important to the economy of the state. Species from throughout the region spend part of their life cycle in the coastal wetlands, including many marine and coastal-dependent species, making this zone critical to the ecosystem health of the Everglades and the SFCME. However, the coastal wetlands are increasingly vulnerable due to rising sea level, changes in storm intensity and frequency, land use, and water management practices. They are at the boundary of the region covered by the Comprehensive Everglades Restoration Plan (CERP), and thus are impacted by both CERP and marine resource management decisions. An integrated conceptual ecological model (ICEM) for the southwest coastal wetlands of Florida was developed that illustrates the linkages between drivers, pressures, ecological process, and ecosystem services. Five ecological indicators are presented: (1) mangrove community structure and spatial extent; (2) waterbirds; (3) prey-base fish and macroinvertebrates; (4) crocodilians; and (5) periphyton. Most of these indicators are already used in other areas of south Florida and the SFCME, and therefore will allow metrics from the coastal wetlands to be used in system-wide assessments that incorporate the entire Greater Everglades Ecosystem.

Nutrition Education Intervention with Community-Dwelling Older Adults: Research Challenges and Opportunities

This study critically reviewed empirical literature examining nutrition education intervention studies with community-dwelling older adults over the period 2003-2012 to: (1) determine the number, (2) evaluate the research designs, and (3) report the study outcomes. A search of online databases yielded 74 studies six of which met our criteria. The studies reported favorable intervention outcomes. Because of the number, variability in the types, designs, measures, scope, educational and behavioral strategies, results can only inform future studies and encourage scholars to use strong evaluation design. We recommend the utilization of an ecological conceptual model when conducting nutrition interventions studies and discussed implications in terms of research and practice.

Socio-Agricultural Bridging Park: A Conceptual Urban Project in Suburban Area

Suburban development in large urban region of Europe, North America and Asia continues to erode forest and farm, disrupt hydrological patterns, and weaken the overall ecological integrity of the region. Fragmented landscapes and equally fragmented communities isolate citizens from nature as well as from one another. Alternative design approaches and models for creating sustainable communities are urgently required to address these problems. This paper presents one such conceptual ecological project model, named Socio-Agricultural Bridging Park (SABP) using criteria developed from a wide range of exemplary sustainable community approaches employed over the world. The basic of this project concept is to ascertain a high level of sustainability and to improve a community’s sense of the civic and sense of place. As a part of the study, a suburban area of the city of Milan was selected. In this paper, a local problem of a Suburban area Municipality (Municipality of Settimo Milanese) is addressed and the concept of SABP is approached to solve the problem of fragmented suburban area. The project concept is also linked with the global event world expo-2015 as Milan will host the event. Journal of Bangladesh Institute of Planners, Vol. 5, Dec 2012, pp. 129-138

Incorporating ecological principles into statistical models for the prediction of species’ distribution and abundance

Understanding the determinants of species’ distributions and abundances is a central theme in ecology. The development of statistical models to achieve this has a long history and the notion that the model should closely reflect underlying scientific understanding has encouraged ecologists to adopt complex statistical methods as they arise. In this paper we describe a Bayesian hierarchical model that reflects a conceptual ecological model of multi‐scaled environmental determinants of riverine fish species’ distributions and abundances. We illustrate this with distribution and abundance data of a small‐bodied fish species, the Empire gudgeon Hypseleotris galii, in the Mary and Albert Rivers, Queensland, Australia. Specifically, the model sought to address; 1) the extent that landscape‐scale abiotic variables can explain the species’ distribution compared to local‐scale variables, 2) how local‐scale abiotic variables can explain species’ abundances, and 3) how are these local‐scale relationships mediated by landscape‐scale variables. Overall, the model accounted for around 60% of variation in the distribution and abundance of H. galii. The findings show that the landscape‐scale variables explain much of the distribution of the species; however, there was considerable improvement in estimating the species’ distribution with the addition of local‐scale variables. There were many strong relationships between abundance and local‐scale abiotic variables; however, several of these relationships were mediated by some of the landscape‐scale variables. The extent of spatial autocorrelation in the data was relatively low compared to the distances among sampling reaches. Our findings exemplify that Bayesian statistical modelling provides a robust framework for statistical modelling that reflects our ecological understanding. This allows ecologists to address a range of ecological questions with a single unified probability model rather than a series of disconnected analyses.

Integrated ecosystem health assessment of a macrophyte-dominated lake

A set of ecological indicators were proposed for the lake ecosystem health assessment via the application of structural, functional, and system-level responses of whole-lake ecosystems to land-use types, chemical stressors including nutrients and organic pollution, and physical stressors including water depth (WD) and grain size (GR). The structural metrics incorporated Chlorophyll c/Chlorophyll a (Chl c/a), Shannon diversity index (H), and proportion of Bacillariophyta (BAC). The functional metrics encompassed leucine amino peptide enzymes (LEU) and general primary productivity (GPP). The ecosystem level indicators consisted of eco-exergy (Ex), structural eco-exergy (Exst), and ecological buffer capacity (βTP-A). Using these indicators, we developed an integrated ecological health modeling method (IEHMM) for macrophyte-dominated lake health assessment. The IEHMM was designed to: (1) identify the relevant questions related to the health of the ecosystem; (2) analyze the lake's ecosystem structure including the pelagic and benthic pathways and use these results to determine the model's structure and complexity; (3) establish a whole-lake ecological conceptual model; (4) calculate the lake's ecosystem health indicators; (5) assess lake ecosystem health using these different indicators; and (6) compare the assessment results with different calculation methods. The IEHMM conceptual model included 5 sub-models and 15 state variables. The results of the case study in Baiyangdian Lake (China) demonstrated that the IEHMM provided comprehensive assessment results that corresponded with the lake's actual health state.

To threshold or not to threshold? That's the question

The concept of evaluating multiple alternative models to determine ecological response form is over a century old and is ever more relevant as modern computing power allows ever more complicated models to be routinely used but often without a reasonable model verification process, particularly in fields where the ecological conceptual model is still developing. The emphasis for developing a statistical model is to test the validity of the hypothesis represented by the model. We present a framework of model identification and evaluation that includes exploratory data analysis and model diagnostics and evaluation. This framework emphasizes the importance of evaluating multiple alternative models when evaluating the validity of the model. This process is illustrated by using a model-building problem for quantifying the stream ecological response to urbanization using a data set from a large ecological study designed to understand how stream ecosystems respond to urbanization. The paper focuses on the question of whether a threshold model is appropriate, and demonstrates the importance of evaluating multiple alternative models in the detection of ecological thresholds, and illustrates how choosing an inappropriate model can lead to erroneous conclusion regarding the existence of thresholds.

Access to oral health services for urban low‐income Latino children: social ecological influences

Using an ecological conceptual model, this study examined the social context, structural, and behavioral factors within an immigrant community that contribute to increased access and use of oral health services by Latino children. The predictors of health service use at the level of the individual, the family, the provider, and the health service system were studied for their effects on the initiation of care, continuity of care, and frequency of planned visits. In-depth face-to-face interviews were conducted with 320 Latino mothers regarding their use of oral health services for 4-8-year-old children [Mexican (n = 221), Puerto Rican (n = 69), and Central and South American (n = 30)]. Outcome measures of dental care utilization were early age at initiation of care, continuity of care, and frequency of planned dental visits. Regular planned dental visits were significantly related to the structural variables of household income and provider availability. The initiation of dental care was related to the mother's beliefs about the value of early preventive dental care. Mothers were more likely to continue care if they believed that the purpose was to keep the child's teeth healthy and had satisfactory communication with the dentist. Identifying the structural and behavioral factors that increase the likelihood of the use of oral health services can provide the basis for developing effective interventions specific to Latino children at the neighborhood level. The study findings can be also used for designing culturally appropriate oral health promotion programs and provider coordination of care.