Single City Research Articles

Research progress on relationship between urban greenspace distribution and the socioeconomic characteristics of residents

Urban greenspace, which serves as a place for residents to connect with nature and relax, provides important ecosystem services. Access to greenspace is often related to the socio-economic characteristics of residents, which received a lot attention from researchers and practitioners. Previous studies have mostly focused on single city to analyze the spatial relationship between greenspace distribution and residents' characteristics. We conducted a meta-analysis with global studies. The objectives were to classify findings from different cases and investigate the impacts from the location of research area, indicator and analytical method, and summarized major factors influen-cing the relationship between greenspace distribution and residents' characteristics. The results showed that more than half of the cases (58.2%) found that the socially advantaged population benefited more from greenspace. About a quarter cases (25.4%) revealed the opposite, that was, the disadvantaged population benefited more from greenspace. The remaining case studies (16.4%) did not find significant correlation between them. The studies reviewed here were diverse in terms of scale, indicator selection, and analytical method. Overall, we found no connection between finding and the choice of scale/indicator/analytical method. The reviewed case studies were mostly conducted in cities of western countries, which differed in their development trajectories and urban characteristics from cities in China. To understand association between urban greenspace and residents' characteristics in China, we urged to carry out more local studies, which would potentially provide scientific evidence for building sustainable cities during rapid urbanization.

Problem of Location of Taxi Ranks and Taxi Dispatch Service Operations in Moscow

The article considers the technological aspects of organization of passenger and baggage transportation by taxi cabs in megacities, referring particularly to the practices of a number of countries.The authors analyze l e g a l regulation and technological development of taxi services in Moscow metropolitan area, including the current system for organizing the work of passenger taxi dispatch services taking into account centralization of information flows in a single city system.An analysis of methods for planning placement of taxi ranks shows that outdated approaches are used to solve that problem without using modern information and communication technologies. In this regard, the methodological foundations of planning the organization of taxi ranks based on geoinformation data in the city of Moscow are proposed.The studies and analysis made it possible to determine relevance and feasibility of existing and justification for planning of new taxi ranks, taking into account the requirements for rationality of location of taxi ranks from the point of view of ensuring a small walking distance for passengers, as well as reducing time of car delivery. The proposed method using accurate coordinates transmitted by the largest taxi dispatch service companies into the Unified Regional Navigation and Information System of the city of Moscow allows to implement these requirements.

Оповіщення населення великих міст про загрозу або виникнення надзвичайних ситуацій: реалізація повноважень органів управління

Розглянуто норми законодавства про виконання органами місцевого самоврядування завдань щодо оповіщення населення великих міст. Проаналізовано стан експлуатації та модернізації місцевих систем централізованого оповіщення. Надано рекомендації щодо удосконалення механізмів управління системами.

City-scale solutions for the energy use of shallow urban subsurface resources – Bridging the gap between theoretical and technical potentials

One solution for reducing the current consumption of fossil fuels is a more frequent use of shallow geothermal energy. However, particularly regarding urban subsurface resources, increased use conflicts are predictable. Consequently, reasonable exploitation of subsurface resources requires an assessment of technologically achievable energy potentials with scientific based tools. We present application-oriented management tools which target on deriving shallow subsurface energy potentials. 3D groundwater flow and heat-transport models are used to capture groundwater flow and heat-transport dynamics on the city- and quarter-scale, 2D box models are used to quantify technically feasible extraction rates of well doublets for groundwater heat pump systems.For Basel (Switzerland), prospective large theoretical energy potentials can be derived for areas with high advective heat flux and high temperature gradients. Likewise, single city quarters are suitable for ‘active’ thermal use with well doublets, whereas thermal power potentials reach 1.2 MW. Regarding ‘passive’ installations of energy absorbers in subsurface structures located within the groundwater, energy potentials amount to 4 and up to 40 W m−2.The assessment results can be integrated into urban energy plans and support architects, city planners and potential users to acquire initial site-specific information on the technical feasibility of shallow geothermal energy systems.

Agent-based simulations of China inbound tourism network

Based on the results of a large-scale survey, we construct an agent-based network model for the China independent inbound tourism system and, by the approach of numerical simulation, investigate the responses of the tourist behaviors to perturbations in different scenarios, including the closure of a tourism city, the opening of a new port city in western China, and the increase of the tourism attractiveness of a specific city. Numerical results show that: (1) the closure of a single city in general will affect the tourist visitations of many other cities and, comparing to the non-port cities, the overall visitation volume of the system is more influenced by closing a port city; (2) the opening of a new port city in western China will attract more tourists to the western cities, but has a negligible impact on either the overall visitation volume or the imbalanced tourist distribution; and (3) the increase of the tourism attractiveness of a non-port (port) city normally increases (decreases) the overall visitation volume, yet there are exceptions due to the spillover effect. Furthermore, by increasing the tourism attractiveness of a few cities simultaneously, we investigate also the strategy of multiple-city-upgrade in tourism development. We find that the overall tourist volume is better improved by upgrading important non-port cities that are geographically distant from each other. The study reveals the rich dynamic inherent in complex tourism network, and the findings could be helpful to the development and management of China inbound tourism.

The relationship of recalled adverse parenting styles with maladaptive schemas, trait anger, and symptoms of depression and anxiety

BackgroundYoung's contention that early maladaptive schemas mediate the relationship between adverse parenting and later emotional difficulties has been lrttle tested. Also, most relevant research focuses only on depression, and on maternal parenting. MethodsOne hundred and fifty-five non-clinical adults completed the Young Parenting Inventory (YPI) regarding both their mothers and fathers, Young's Schema Questionnaire (YSQ), the State/Trait Anger Scale (STAS) and the Depression Anxiety Stress Scale-21 (DASS-21). ResultsYoung's suggested 17-factor YPI structure was not supported. Rather, participants differentiated between recalled paternal and maternal parenting, with rejecting and controlling components emerging for each parent. There was an indirect effect of rejecting fathering on symptoms of depression, via the social isolation schema, in support of Young's theory. However, despite some significant relationships between parenting and schemas, and schemas and emotions, most effects of parenting on emotions were direct. Rejecting fathering had a direct positive effect on trait anger, and controlling mothering on symptoms of depression and anxiety. Controlling fathering had a negative effect on anxiety symptoms. LimitationsThe study was cross-sectional, limited to participants in a single city, and had a preponderance of female respondents. ConclusionsMost effects of adverse parenting seem to be direct rather than operating through schemas. Prevention through early parenting programs, and adult cognitive therapies that draw on a broad range of schemas, seem to be called for.

Risk Factors for a False-Negative Examination in Complete Upper Extremity Nerve Lacerations

Background: Many patients with complete nerve lacerations after upper extremity trauma have a documented normal peripheral nerve examination at the time of initial evaluation. The purpose of this study was to determine whether physician-, patient-, and injury-related factors increase the risk of false-negative nerve examinations. Methods: A statewide health information exchange was used to identify complete upper extremity nerve lacerations subsequently confirmed by surgical exploration at 1 pediatric and 2 adult level I trauma centers in a single city from January 2013 to January 2017. Charts were manually reviewed to build a database that included Glasgow Coma Scale score, urine drug screen results, blood alcohol level, presence of concomitant trauma, type of injury, level of injury, laterality, initial provider examination, and initial specialist examination. Bivariate and multivariable analyses were performed to evaluate risk factors for a false-negative examination. Results: Two hundred eighty-eight patients met inclusion criteria. The overall false-negative examination rate was 32.5% at initial encounter, which was higher among emergency medicine physicians compared with extremity subspecialists (P < .001) and among trauma surgeons compared with surgical subspecialists (P = .002). The false-negative rate decreased to 8% at subsequent encounter (P < .001). Risk factors for a false-negative nerve examination included physician specialty, a gunshot wound mechanism of injury, injury at the elbow, and age greater than 71 years. Conclusion: There is a high false-negative rate among upper extremity neurotmesis injuries. Patients with an injury pattern that may lead to nerve injury warrant prompt referral to an upper extremity specialist in an effort to optimize outcomes.

Sustainable Transportation in Metropolitan Cities; Berlin, Helsinki, New Delhi and Pune

If one comprehends a city as a human body, then transportation would be its arteries and veins. It makes mobilization possible. In the age of rapid globalization transportation does not only concern itself with a single city but transportation deals with a global scale today. This paper focuses on a comparative analysis of transportation methods for four cities in terms of how new sustainable transportation concepts can be applied to make our future better. The discussion includes a vast range of possibilities of our future sustainable cities in transportation. Environmental and technological aspects as well as politics and policies are inspected. Cities flourish, develop and revolve around transportation. Our future sustainable cities would be no different. We need to approach transportation from all the three aspects of sustainability e.g. social, ecological, and environmental. We have chosen our cities for case studies on a broad range from low-density in Helsinki to very high population in Delhi. The rapid growth in transportation has remarkably increased the carbon footprints of our cities. While planning for our future cities making transportation sustainable is of paramount importance. To understand the issue of transportation for our sustainable cities we discuss the present state of transportation globally and analyse transportation in major cities such as Berlin, Delhi, Helsinki and Pune.

Challenges with quality of race and ethnicity data in observational databases.

We sought to assess the quality of race and ethnicity information in observational health databases, including electronic health records (EHRs), and to propose patient self-recording as an improvement strategy. We assessed completeness of race and ethnicity information in large observational health databases in the United States (Healthcare Cost and Utilization Project and Optum Labs), and at a single healthcare system in New York City serving a racially and ethnically diverse population. We compared race and ethnicity data collected via administrative processes with data recorded directly by respondents via paper surveys (National Health and Nutrition Examination Survey and Hospital Consumer Assessment of Healthcare Providers and Systems). Respondent-recorded data were considered the gold standard for the collection of race and ethnicity information. Among the 160 million patients from the Healthcare Cost and Utilization Project and Optum Labs datasets, race or ethnicity was unknown for 25%. Among the 2.4 million patients in the single New York City healthcare system's EHR, race or ethnicity was unknown for 57%. However, when patients directly recorded their race and ethnicity, 86% provided clinically meaningful information, and 66% of patients reported information that was discrepant with the EHR. Race and ethnicity data are critical to support precision medicine initiatives and to determine healthcare disparities; however, the quality of this information in observational databases is concerning. Patient self-recording through the use of patient-facing tools can substantially increase the quality of the information while engaging patients in their health. Patient self-recording may improve the completeness of race and ethnicity information.

Lower dietary variety is a relevant factor for malnutrition in older Japanese home-care recipients: a cross-sectional study

BackgroundNutritional status of the older people is affected by various life-style factors. Although dietary habit is one of the life-style factors, it is unknown which of older home-care recipients’ dietary habits are associated with malnutrition.The purpose of this study was to examine the association of dietary variety, as an evaluation index for dietary habits, with malnutrition in Japanese older home-care recipients.MethodsThis cross-sectional study was conducted in a single city, Hyogo Prefecture, Japan between July and October 2016. Three hundred thirty-three community-dwelling older care recipients (aged 65 years or older who were receiving home-visit nursing care services) were enrolled. Their nutritional status (Mini Nutritional Assessment®-short form: MNA®-SF), dietary variety (Food frequency score [FFS]), socio-demographic characteristics (age, sex, marital status, etc.), health indicators (comorbidity [Charlson Comorbidity Index] and dysphagia status [Dysphagia Severity Scale]) were assessed. The participants were classified into two groups: malnourished (0–7 points) and non-malnourished (8–14 points), according to their MNA®-SF scores. Multivariate logistic regression analysis was used to examine the factors associated with malnutrition.ResultsA total of 317 participants were analyzed (118 men, 199 women, median age: 84 years). Compared to the fourth (highest) quartile of FFS, odds ratios (OR) (95% confidence intervals [CI]) of the third, second, and first (lowest) quartiles of FFS were 1.08 (0.42–2.80), 1.29 (0.56–2.98), and 2.30 (1.02–5.19), respectively (p for trend = 0.049). Higher Charlson Comorbidity Index score and the presence of dysphagia were also significantly associated with malnutrition (OR: 2.08, 95% CI: 1.08–4.00 and OR: 3.86, 95% CI: 2.08–7.17, respectively).ConclusionLower dietary variety was significantly associated with malnutrition in Japanese older home-care recipients.

Optimizing the Development Area to take the lead in Peaks-based on Location Quotient Analysis

The China Optimized Development Area was officially released in the National Main Functional Area Plan in 2011. It is an important population and economically intensive area of China and has a huge impact on China’s future development. Under the background of international commitment and national planning to reduce carbon emission intensity, China’s optimized development area should play a leading role. Based on the location quotient analysis method, this paper analyzes the basis and prospects of optimizing the development area to take the lead from the industrial structure level, and draws the following conclusions. From the perspective of a single city, it compares with the overall industrial structure of the country and obtains optimization. Compared with the whole country, the development zone has a better industrial structure as the basis for carbon emission peaks. The optimized development zone should continue to carry forward its advantages in industrial structure and play a leading role in China’s 2030 carbon emission peak.

Administrative hierarchy, housing market inequality, and multilevel determinants: a cross-level analysis of housing prices in China

Numerous studies have examined the determinants of housing prices in Chinese cities. However, most of them ignored the hierarchical structural characteristics of housing prices because of the use of ordinary least squares and hedonic pricing to model the housing prices for a single city. Therefore, this study explores the multi-level determinants of housing prices and their interactions at different levels. To this end, it proposes a three-level hierarchical linear model (HLM) using observations from 146,099 communities nested in 1120 counties of 31 provinces in China as a case study. The results of the hierarchical linear regression indicate significant variances in average housing prices. This finding suggests HLM to be appropriate when dealing with housing prices inherently nested at multiple geographic levels. Overall, housing values in China are not only determined by accessibility factors but are also driven by multi-level socioeconomic aspects. Among the selected variables, high-speed railway shows a significant positive effect, while ordinary railway shows a significant negative effect on housing values at the community level. At the county level, rural–urban migration and per capita living space have significant positive impacts on housing value. At the province level, the relationship between rural–urban migration and housing prices depends on economic development and urban employment. Similarly, the average wages of urban employment influence the relationship between per capita living space and housing prices. These results suggest that contextual effects exist between the determinants of housing prices at county and province levels.

Extracting Spatial Patterns of Intercity Tourist Movements from Online Travel Blogs

Spatial patterns of tourist mobility are important for tourism management and planning. A large number of traveler-generated content accumulated on the internet provide a unique opportunity for revealing comprehensive spatial patterns of tourist movements. Instead of concentrating on a single city or attraction in previous research, this work investigates the intercity travel flows extracted from the online travel blogs in China from 2012 to 2016. The descriptive statistics of travel flows are first analyzed. The distribution of travel volume is found to satisfy the power-law distribution. Based on the intercity travel flows, a network structure is then constructed to investigate tourism interactions between cities. After four communities and 14 sub-communities being detected from the network, a tourism spatial layout with regional agglomeration effects are recognized. This research concludes that distance is essential in determining tourist movements based on a spatial interaction model. Intercity travel flows decline with distance under a power-law function. These results reveal the spatial patterns of tourist movements at an intercity scale. It will be helpful for arranging tourism resources, predicting tourist flows, and maintaining sustainable tourism.

Effectiveness of vegetated patches as Green Infrastructure in mitigating Urban Heat Island effects during a heatwave event in the city of Melbourne

The city of Melbourne in southeast Australia experiences frequent heatwaves and their frequency, intensity and duration are expected to increase in the future. In addition, Melbourne is the fastest growing city in Australia and experiencing rapid urban expansion. Heatwaves and urbanization contribute in intensifying the Urban Heat Island (UHI) effect, i.e., higher temperatures in urban areas as compared to surrounding rural areas. The combined effects of UHI and heatwaves have substantial impacts on the urban environment, meteorology and human health, and there is, therefore, a pressing need to investigate the effectiveness of different mitigation options. This study evaluates the effectiveness of urban vegetation patches such as mixed forest (MF), combination of mixed forest and grasslands (MFAG), and combination of mixed shrublands and grasslands (MSAG) in reducing UHI effects in the city of Melbourne during one of the most severe heatwave events. Simulations are carried out by using the Weather Research and Forecasting (WRF) model coupled with the Single Layer Urban Canopy Model (SLUCM). The fractions of vegetated patches per grid cell are increased by 20%, 30%, 40% and 50% using the mosaic method of the WRF model. Results show that by increasing fractions from 20 to 50%, MF reduces near surface (2 m) UHI (UHI2) by 0.6–3.4 °C, MSAG by 0.4–3.0 °C, and MFAG by 0.6–3.7 °C during the night, but there was no cooling effect for near surface temperature during the hottest part of the day. The night-time cooling was driven by a reduction in storage heat. Vegetated patches partitioned more net radiation into latent heat flux via evapotranspiration, with little to no change in sensible heat flux, but rather, a reduction in the storage heat flux during the day. Since the UHI is driven by the release of stored heat during the night, the reduced storage heat flux results in reductions in the UHI. The reductions of the UHI2 varied non-linearly with the increasing vegetated fractions, with lager fractions of up to 50% resulting in substantially larger reductions. MF and MFAG were more effective in reducing UHI2 as compared to MSAG. Vegetated patches were not effective in improving HTC during the day, but a substantial improvement of HTC was obtained between the evening and early morning particularly at 2100 local time, when the thermal stress changes from strong to moderate. Although limited to a single heatwave event and city, this study highlights the maximum potential benefits of using vegetated patches in mitigating the UHI during heatwaves and the overall principles are applicable elsewhere.

What can urban mobility data reveal about the spatial distribution of infection in a single city?

BackgroundInfectious diseases spread through inherently spatial processes. Road and air traffic data have been used to model these processes at national and global scales. At metropolitan scales, however, mobility patterns are fundamentally different and less directly observable. Estimating the spatial distribution of infection has public health utility, but few studies have investigated this at an urban scale. In this study we address the question of whether the use of urban-scale mobility data can improve the prediction of spatial patterns of influenza infection. We compare the use of different sources of urban-scale mobility data, and investigate the impact of other factors relevant to modelling mobility, including mixing within and between regions, and the influence of hub and spoke commuting patterns.MethodsWe used journey-to-work (JTW) data from the Australian 2011 Census, and GPS journey data from the Sygic GPS Navigation & Maps mobile app, to characterise population mixing patterns in a spatially-explicit SEIR (susceptible, exposed, infectious, recovered) meta-population model.ResultsUsing the JTW data to train the model leads to an increase in the proportion of infections that arise in central Melbourne, which is indicative of the city’s spoke-and-hub road and public transport networks, and of the commuting patterns reflected in these data. Using the GPS data increased the infections in central Melbourne to a lesser extent than the JTW data, and produced a greater heterogeneity in the middle and outer regions. Despite the limitations of both mobility data sets, the model reproduced some of the characteristics observed in the spatial distribution of reported influenza cases.ConclusionsUrban mobility data sets can be used to support models that capture spatial heterogeneity in the transmission of infectious diseases at a metropolitan scale. These data should be adjusted to account for relevant urban features, such as highly-connected hubs where the resident population is likely to experience a much lower force of infection that the transient population. In contrast to national and international scales, the relationship between mobility and infection at an urban level is much less apparent, and requires a richer characterisation of population mobility and contact.

Collective sensing of evolving urban structures: From activity-based to content-aware social monitoring

Cities are constantly evolving complex systems. Detection methods of land use distribution have to keep pace with their rapidly changing landscapes. While traditional analysis relies on surveys and census data typically refreshed at most yearly, the widespread use of mobile devices allows cell phone activity measurements to be used as sensors for the functional clustering of urban districts. These activity-based proprietary measurements are recently complemented by publicly available geosocial network records that even enable content-aware analysis. As a bridge between separate methods, in this work we analyze the relation of conversation content and functional spatial clusters of cities using a double dataset approach. We look at the differentiating power of the content of local conversations in activity-driven land use detection based on mobile phone records. In addition to intra-city analysis of three metropolises, we present a comparative study of London, New York City, and Los Angeles sharing the common language of English, but having very different cultural backgrounds. We show that the share of words with a similar temporal pattern to that of local mobile activities is different across cities, as well as between functional clusters. We find that the conversational content can effectively differentiate both functional clusters of a single city, and similar locations of the same function across many cities, like business areas that otherwise have a common temporal heartbeat. Moreover, we identify words related to activity types as the most important features emerging from the content-based, data-driven classification.

Capturing the true value of trees, cool roofs, and other urban heat island mitigation strategies for utilities

A growing body of research values the broad benefits of cooling down cities, such as improved energy efficiency, worker productivity, air quality, health, and equity, at hundreds of millions or even billions of dollars to a single city. However, widespread adoption of urban heat mitigation programs, such as urban greening and reflective surfaces, has been slower than their economic potential suggests it should be. One possible cause for this lag is a lack of robust engagement from important stakeholders like utilities that could fund and implement heat mitigation strategies. This paper highlights the benefits of urban heat mitigation and demonstrates how these benefits fit into private utility programs’ standard cost–benefit tests. This paper serves as an introduction on how to include the wide suite of benefits that urban heat mitigation programs provide in cost–benefit tests and concludes with program design guidance.

Advancing urban wildlife research through a multi‐city collaboration

Research on urban wildlife can help promote coexistence and guide future interactions between humans and wildlife in developed regions, but most such investigations are limited to short‐term, single‐species studies, typically conducted within a single city. This restricted focus prevents scientists from recognizing global patterns and first principles regarding urban wildlife behavior and ecology. To overcome these limitations, we have designed a pioneering research network, the Urban Wildlife Information Network (UWIN), whereby partners collaborate across several cities to systematically collect data to populate long‐term datasets on multiple species in urban areas. Data collected viaUWINsupport analyses that will enable us to build basic theory related to urban wildlife ecology. An analysis of mammals in seven metropolitan regions suggests that common species are similar across cities, but relative rates of occupancy differ markedly. We ultimately viewUWINas an applied tool that can be used to connect the public to urban nature at a continental scale, and provide information critical to urban planners and landscape architects. Our network therefore has the potential to advance knowledge and to improve the ability to plan and manage cities to support biodiversity.

Abstract 164: Neighborhood Socioeconomic Status is Significantly Associated with Outcomes After Coronary Artery Bypass Grafting

Objective: Area Deprivation Index (ADI) is a geographically-derived measure of socioeconomic status composed of 17 education, employment, housing-quality, and poverty measures derived from census data. Block group level ADI has recently been made widely accessible to clinicians. A block group is the smallest geographical unit from which census data is collected, representing a homogenous group of people living on a single city block or rural equivalent. Previous work analyzing the relationship of socioeconomic status with cardiac surgery outcomes has been limited by the use of zip codes as the geographic unit, which comprise a larger and more diverse population. This study evaluates the association of ADI with outcomes after coronary artery bypass grafting (CABG). Methods: Patients who underwent isolated CABG in the University of Pennsylvania health system between 2002 and 2018 with a valid home address were assigned an ADI based on their corresponding 2010 Census Block Group. The association between ADI and each STS post-operative outcome was assessed with univariable analysis using a Wilcoxon rank sum test with continuity correction. A multivariable logistic regression model was created for each STS post-operative outcome using variables in the 2008 STS risk model for CABG with ADI as an additional variable. Results: The 6,751 patients who met the inclusion criteria were from 19 states with a median predicted STS risk of post-operative major morbidity and mortality of 16.6% (IQR 7.0% to 19.9%) and median ADI of 31 (IQR 17 to 50). ADI was not normally distributed by Wilcoxon signed rank test (p &lt; 0.01). ADI was significantly associated with stroke (p = 0.03), renal failure (p &lt; 0.01), prolonged ventilation (p &lt; 0.01), reoperation (p = 0.05), and composite morbidity and mortality (p &lt; 0.01) in univariable analysis. When included in a multivariable logistic regression model ADI was significantly associated with renal failure (p = 0.02), prolonged ventilation (p &lt; 0.01), and composite morbidity and mortality (p &lt; 0.01). Conclusions: ADI is associated with STS post-operative outcomes. When included in a multivariable model, ADI remains highly associated with outcomes. Inclusion of block group level socioeconomic status in prediction models may significantly improve risk prediction.

Economic and socio-cultural consequences of changing political rule on human and faunal diets in medieval Valencia (c. fifth\u2013fifteenth century AD) as evidenced by stable isotopes

This paper explores the impact of changing religious political rule on subsistence within a single city through time using stable isotope analysis of human and animal bone collagen. The diet and economy of the medieval city of Valencia (Spain) are examined over a 1000-year period during successive periods of Visigothic, Muslim and Christian rule. Bulk stable isotope analysis of carbon (δ13C) and nitrogen (δ15N) was carried out on 67 humans and 47 animals sampled from several archaeological sites dating between the fifth and fifteenth centuries AD. Terrestrial C3 resources dominated the diet in all periods. However, an increase in consumption of C4 plants (e.g. millet, sorghum) and/or marine resources is detected among individuals dating to the Islamic period. Differences in the isotopic values of humans and animals between the three periods indicate a significant dietary diversity during the Islamic phases (eleventh to thirteenth century), compared with the earlier Visigothic phase (fifth–seventh century) and the later Christian phase (fourteenth and fifteenth century). Observed diachronic changes in isotopic results provide evidence for a shift in diet and subsistence, particularly during the Muslim and later Christian periods. This is linked with change in population and economic focus. Dietary diversity among Muslim individuals is hypothesised to indicate the polyculture that was reflected in varied Islamic agricultural practices and the presence of potential migrants from elsewhere in the Islamic world.