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Carpophilus davidsoni (Dobson) is an important pest of Australian stone fruit. Current management practices for this beetle include the use of a trap that contains an attractant lure comprised of aggregation pheromones and a ‘co-attractant’ mixture of volatiles from fruit juice fermented using Baker’s yeast, Saccharomyces cerevisiae (Hansen). We explored whether volatiles from yeasts Pichia kluyveri (Bedford) and Hanseniaspora guilliermondii (Pijper), which are closely associated with C. davidsoni in nature, might improve the effectiveness of the co-attractant. Field trials using live yeast cultures revealed that P. kluyveri trapped higher numbers of C. davidsoni compared to H. guilliermondii, and comparative GC-MS of volatile emissions of the two yeasts led to the selection of isoamyl acetate and 2-phenylethyl acetate for further investigation. In subsequent field trials, trap catches of C. davidsoni were significantly increased when 2-phenylethyl acetate was added to the co-attractant, compared to when isoamyl acetate was added, or both isoamyl acetate and 2-phenylethyl acetate. We also tested different concentrations of ethyl acetate in the co-attractant (the only ester in the original lure) and found contrasting results in cage bioassays and field trails. Our study demonstrates how exploring volatile emissions from microbes that are ecologically associated with insect pests can result in more potent lures for use in integrated pest management strategies. Results from laboratory bioassays screening volatile compounds should be treated with caution when making inferences regarding attraction under field conditions.

The global target to achieve inclusive public transportation includes the availability of courtesy seating for vulnerable individuals such as elderly people, people with disabilities, pregnant women, and children. The frequent usage of courtesy seats by passengers who are not vulnerable individuals is an issue pertaining to public transportation. It is important to encourage the travelers to yield seats in the presence of vulnerable individuals because the latter might get seriously injured by falling if they stay on a moving vehicle. This study explores the influence of incentives and situational factors affecting individuals’ decisions to yield seats to vulnerable people. Through an online questionnaire survey, 404 valid responses were obtained. The generalized linear mixed model (GLMM) with repeated measures was used to identify the influential factors affecting the self-reported decisions of yielding seats to vulnerable individuals. The results indicate that the situational factors (health, crowd, vulnerable passenger type, standing time after yielding seats), incentive types, and incentive amounts are significant factors affecting the decisions to yield seats. The study’s findings also indicate that travelers are more sensitive to people with disabilities and pregnant women than to elderly people and children. The practical implications, including campaigning, education interventions, and incentive-based mechanism, were suggested to encourage travelers to yield seats to vulnerable individuals.

Partial filling of a porous medium in a channel of a certain configuration attracts attention, as it tends to enhance convective heat transfer while reducing pressure drop remarkably, as compared t...

The continuous increase in the elderly population and the need for disability-inclusive public transportation propelled authorities to implement policies to ensure seat availability for vulnerable users. Although most public transportation provides a few priority seats for vulnerable users, the seat availability problem remains due to its small quantity and its usage by normal passengers. To extend the theory of planned behavior (TPB), this study aims to evaluate how empathic concerns, attitude, injunctive norms, descriptive norms, and perceived behavioral control contribute to the behavioral intentions and actual conducts of yielding seats to vulnerable passengers with university students’ survey responses in China. A partial least square path modeling based structural equation modeling (SEM) approach is employed to test the postulated hypotheses. Findings reveal that empathic concerns significantly promote the yielding seat intention and, thus, the actual conduct through its impacts on attitude, injunctive norms, and perceived behavioral control. This study also aims at capturing sociodemographic heterogeneity through multi-group comparison. It is found that a university student passenger who is older or more educated perceives greater control about seat yielding behavior, positively influencing their intention to yield their seat to a vulnerable person. In addition, less frequent public transportation usage is found to significantly accompany a higher tendency to yield a seat when required. The implications of “soft measures” to support the transportation policy for a sustainable and disability-inclusive public transportation service are discussed accordingly.

Sustainable development has become an immense challenge, one further complicated by rapid population growth in developing countries. Therefore, analyzing the existing compactness of urban areas is essential for guiding future urban development. Most of the previous research on urban compactness has been conducted in developed countries, whereas limited research has been conducted on urban compactness in developing countries. This study fills this research gap and contributes to the current body of knowledge by offering empirical evidence of compactness measurement based on the existing urban form using Multan city as its context. Multan is a metropolitan city in the growing phase, so measuring its compactness for the promotion of sustainable development is crucial. For this research study, various indicators are adopted from the literature, such as land cover changes, density, land use, road network, congestion index, walkability index, and shape performance index, in order to evaluate compactness. The above-mentioned indicators were analyzed using ArcMap and ERDAS IMAGINE software. This study concludes that Multan city presently lies between compactness and dispersion. To achieve full compactness, highly dense vertical development with a better public transport network should be encouraged. In addition, the prevailing building regulations should be revised to increase the floor area ratio, and incentives should be devised for developers to promote vertical infill development. Moreover, there is an emerging need to formulate and implement compact city policies. By retaining the compact character of Multan city, sustainable development will be promoted. Ultimately, this research study would be a valuable resource for urban planners, decision-makers, and relevant authorities in proposing future compactness policies for sustainable development. This research can be applied to other cities with similar demographic characteristics, population, area, geographical conditions, and structure to that of Multan.

Partial filling of porous medium insert in a channel alleviates the tremendous pressure drop associated with a porous medium saturated channel, and enhances heat transfer at an optimum fraction of porous medium filling. This study pioneered an investigation into the viscous dissipative forced convective heat transfer in a parallel-plate channel, partially occupied with a porous medium at the core, under local thermal non-equilibrium condition. Solving the thermal energy equation along the Darcy-Brinkman equation, new exact temperature fields and Nusselt number are presented under symmetrical isoflux thermal boundary condition. Noteworthy is the heat flux bifurcation at the interface between the clear fluid and porous medium driven by viscous dissipation, in cases where the combined hydrodynamic resistance to fluid flow and thermal resistance to fluid conduction is considerable in low Darcy number porous medium insert. However, viscous dissipation does not affect the qualitative variation of the Nusselt number with the fraction of porous medium filling. By using Al

Aedes aegypti mosquito is the principal dengue vector in the Kingdom of Saudi Arabia (KSA); however, no study has addressed its ecology and population structure yet. Therefore, we report on Ae. aegypti phylo- and population genetics using three DNA markers: COI, ND4, and rDNA-ITS2. Sampling the immature stages of Ae. aegypti revealed that water storage tanks (34.3% of habitats) were the most productive and contained 33% of immatures stages. Other important habitats included containers for wastewater drainage (including air-conditioning and water cooler trays) and containers associated with ornamentation. Shallow water leakage spots (2.7% of habitats, 8% of immatures) can be considered rare-but-epidemiologically-important containers. Neighbor-joining (NJ) phylogenetic analysis of Ae. aegypti identified 8, 14, and 9 haplotypes of COI, ND4, and ITS2, respectively, and revealed high levels of genetic variation in Ae. aegypti populations of KSA. Global distribution of haplotypes also indicated multiple gene introductions into these populations, with high levels of intra-population genetic variation and continuous gene exchange. The neutrality values indicated a deficiency of alleles and suggested that the KSA Ae. aegypti loci tested did not follow a neutral model of molecular evolution. Fst values and AMOVA indicated that most of the genetic variation in the KSA Ae. aegypti populations is due to intra- rather than inter-population differences. This is the first comprehensive report on the phylo- and population genetics of Ae. aegypti from the Arabian Peninsula. This information expands our understanding of the ecology and population dynamics of this important arboviral vector for informed control efforts.

With the rapid emergence of connected vehicle (CV) technologies, there is a shortage of research to understand CV technology’s effect on drivers’ risk-taking behavioral intentions. This article aims to analyze driver responses to the real-time information by comparing their reactions to driving intentions between the CV and non-CV environments. A multi-group structural equation model (SEM) is employed to explore the heterogeneity in the relationships between behavioral intentions, attitudes, subjective norms, perceived behavioral control, and risk perceptions under the two different environments. This study reveals two key findings: 1) regarding driver responses to the theory of planned behavior (TPB) model, there are significant differences in attitudes and risk perceptions between the CV and non-CV environments; 2) irrespective of driving environments, risk-taking behavioral intentions are directly related to perceived behavioral control and risk perceptions. While intentions are directly related to attitudes but not associated with subjective norms under the non-CV environment. In contrast, intentions are directly related to subjective norms but not associated with attitude under the CV environment. The findings provide a theoretical basis for using TPB to evaluate CV technology’s effects and understanding the differences between the CV and non-CV environments.

A local thermal nonequilibrium Couette flow in a saturated porous medium, subjected to uniform heat flux, is investigated, where concern is focused on the effects of viscous dissipation. The temperature field is derived analytically in terms of Brinkman number (Br) and porous medium shape factor applied to conditions where the local thermal nonequilibrium effect is profound. Contrary to pressure-driven flow in porous medium, viscous dissipation has a more significant effect on the transverse temperature variation of a porous medium with high porous medium shape factor due to the shearing force on the moving wall. A comparison with the local thermal equilibrium model reveals that such an effect is heightened as the thermal resistance to heat conduction in fluid at the heated boundary becomes greater. The computed Nusselt number (Nu) indicates a reversal in the trend of declining Nu with increasing Br as the porous medium shape factor drops below one. As Br is a function of characteristic gap size, this study also gauges the effect of characteristic length scale of the parallel channel on the temperature field. The resulting fluid and solid temperature fields depend strongly on the characteristic gap size between parallel plates, while viscous dissipation intensification overrides the convection enhancement effect in microscale applications.

We explored how gut-associated yeasts influence olfactory behaviour and resource use in two pest species of Carpophilus beetle that co-exist in Australian stone fruits. Molecular analysis of yeasts isolated from the gut of C. davidsoni (prefers ripe fruits) and C. hemipterus (prefers overripe and rotting fruits) revealed that the predominant species were Pichia kluyveri and Hanseniaspora guilliermondii. In olfactory attraction and oviposition trials, adult beetles preferred H. guilliermondii over P. kluyveri, and follow up GC-MS analysis revealed unambiguous differences between the odour profiles of these yeasts. In contrast to behavioural trials, larval feeding assays showed that fruit substrates inoculated with P. kluyveri yielded significantly faster development times, higher pupal mass, and a greater number of adult beetles, compared to H. guilliermondii - in other words, the lesser preferred yeast (by foraging adults) was more suitable for larval survival. Moreover, whilst larvae of both species survived to adulthood when fed solely on P. kluyveri (i.e. without a fruit substrate), only larvae of C. davidsoni could develop on H. guilliermondii; and only C. davidsoni reached adulthood feeding on a yeast-free fruit substrate. We discuss how these findings may relate to adaptations towards early colonising of fruits by C. davidsoni, enabling differences in resource use and potentially resource partitioning in the two beetles. More broadly, consideration of microbial interactions might help develop host selection theory. Our results could pave the way to more powerful attractants to mass-trap and monitor Carpophilus pests in fruit orchards.

Public transport including formal and informal (Paratransit) transport plays an important role in all major cities throughout the world. One of the important issue regarding this type of transport is passenger’s satisfaction. In context of Pakistan, only few studies were conducted on the satisfaction studies regarding public transport. Furthermore, quality of public transport service as per consumers’ desires is an important issue nowadays. This study aims to assess the citizen’s perceived satisfaction regarding the quality of Paratransit public transport as well as to provide guidelines in order to improve the conditions of transportation system. Sample size for the present study was selected as 384 and an online questionnaire survey methodology with simple random sampling was implied to collect the desired data. Respondents filled Likert-scale based questions focusing demographics of the area, and R programming associated with R studio utilized for data analysis. In addition, statistical correlation was also implied to describe the relationship of various factors on overall public transport satisfaction level of people. Study is significant in terms of indicating the alarming situation of public transport in Hyderabad city and providing the public transport satisfaction related statistics, which allows policy planners to make the transport policies as per public interest.

Predictive modeling is the key fundamental method to study passengers’ behavior in transportation research. One of the limited studied topic is modeling of public transport usage frequency, which can be used to estimate present and future demand and users’ trend toward public transport services. The artificial intelligence and machine learning methods are promising to be better substitute to statistical techniques. No doubt, traditionally been used econometrics models are better for causal relationship studies among variables, but they made rigid assumptions and unable to recognize the pattern in data. This paper aims to build a predictive model to solve passengers’ classification, and public transport usage frequency using socio-demographic survey data. The supervised machine learning algorithm, K-Nearest Neighbor (KNN) applied to build a predictive model, which is the better machine learning method for dealing with small datasets, because of its ability of having less parameter tuning. Survey data has been used to train and validate the model performance, which is able to predict public transport usage frequency of future users of public transport. This model can practically be used by public transport agencies and relevant government organizations to predict the public transport demand for new commuters before introducing any new transportation projects.

Road safety accompanying the growing numbers of Road Traffic Deaths (RTDs), is an alarming issue of the present century which is also recognized in WHO agenda-2030. All countries across the globe are facing this issue, but it pertains in developing world where rapid motorization results into high mortality rates. This study considered Pakistan, a developing country from Global south to discuss the issue of RTDs and its relationship with rapid vehicle growth. The objective of the study is to highlight the present situation of road safety especially RTDs and develop models to identify the possible impacts of vehicle growth on RTDs. Linear Regression was performed to develop three models to explain RTDs vs registered vehicle, registered motor cars and registered motorcycles respectively. Descriptive statistics shows the increasing trend of all selected variables which further explained by liner regression equation. Results indicates that annual proportional change in RTDs explain by total registered vehicles, motor cars and motorcycles are 84%, 66% and 80% respectively and comparatively motor cars, motorcycles contributing more arise of RTDs. Study highlights the need of attention towards RTDs and provide models to predict increasing RTDs with vehicle growth. Study is significant as it highlights present situati

Setback is a building regulation enforced to regulate spacing between two buildings in order to have adequate solar exposer and ventilation. It is mandatory on the part of every individual who wants to construct a structure to obtain permission from the local authority before its construction. Despite rules and regulations framed for good reasons, instances of violation of development control rules (especially setback rules) are observed in the residential buildings of Qasimabad, Hyderabad. This results in the obstruction of sunlight, poor ventilation and high consumption of energy. It also results in deteriorating living conditions and narrowing of the adjacent local roads and alleys, creating congestion. So, this paper has tried to highlight the violations of setback rules in residential buildings and their impact on living conditions. For the perception of living conditions, a questionnaire survey with the Likert 5-point scale was used. Field survey technique was also carried out to measure the existing setbacks of residential buildings in Qasimabad. Standardized setbacks were determined by applying the formulas and by comparing them with existing setbacks. The comparison shows that existing setbacks are against building bye-laws. Despite discussing all building laws with various development agencies, this research is limited to discussing the setback rules mentioned in National Reference Manual (NRM). The study reveals that those residents who do not have a side setback area are more concerned with their privacy, smoke, sound and darkness; whereas, ineffective lighting, air circulation and the rise of temperature affect the living conditions and result in high energy consumption by residents. The study is imperative because it brings the focus of the development agencies towards the neglect of setback rules in high rise buildings and provides the evidence of their impact on living conditions by measuring residents’ perceptions.

Livability is an important and crucial aspect of urbanity which depicts quality of life. The emerging cities have a variety of urban challenges, including poor quality of life that has focused urban planners towards livability measures. Pakistani cities are facing similar challenges, like provision of adequate infrastructural facilities and amenities, due to which cities are losing their livability standards. Hyderabad, the second biggest city of Sindh Province, is an emerging metropolitan facing the same dilemma. The objective of this paper is to measure the livability as perceived by the residents. Six urban settlements were selected through stratified sampling to represent three income groups present in the study area, i.e. upper, middle and lower. Through systematic sampling, a sample size of 290 was procured for the household-based questionnaire survey, and descriptive statistics and multiple regression techniques were used. Results showed a significant relationship between perceived livability and livability attributes. The environmental attribute was found most significant in affecting livability perception of residents. The study also highlights eight livability variables which need to be considered for improving the quality of life in future urban development projects, not just in Pakistan, but also other developing countries.

Metro travelers’ travel experience is highly influenced by fellow passengers’ misbehaviors such as eating or littering in the carriage and sound blaster, which are common in the metro carriage. Although operators have implemented various regulations to reduce misbehavior, little theoretical research has investigated such behavior motivators to provide targeted guidelines for specific passenger segments. To this end, this study explores how demographic and perceived social norms of university students affect their misbehaviors, i.e., eating in the carriage, public display of affection, sound blaster, cross-legged sitting, leaning against the pole, and littering, in the metro carriage of Shanghai, China. With the structural equation model, it is revealed that both injunctive and descriptive norms impose significant impacts on passengers’ inappropriate behaviors, with the effect of the former generally to a greater degree. Gender heterogeneity in passenger misbehavior is also observed, where males significantly perform better in eating in the carriage and cross-legged sitting. These findings may decode the underlying motivation of passenger misbehaviors and provide guidelines for effective intervention with targeted policy design and implementation.

The lockdown and social distancing policies to reduce COVID-19 spread and perceived safety threats of COVID-19 significantly affected people’s travel behavior. Greece has been suffering from the COVID-19 pandemic, and people’s mobility behavior has been greatly affected. This study aims at: (1) exploring the variations in individuals’ trip frequencies by mode and purpose before and after the COVID-19 outbreak; (2) understanding the effects of individual differences (i.e., sociodemographic details) and perceptions towards COVID-19 (i.e., the perceived threats of COVID-19) on people’s mobility behavior changes after the outbreak; (3) underlining the individuals’ perceptions of the COVID-19 threat on the willingness of public transportation usage. Overall, 403 responses were collected in late 2020. A series of random parameter Probit modeling results reveal multiple individual and perception factors affecting the changes in mobility behavior in Greece. The results from structural equation modeling indicate that perceived COVID-19 threats affect the attitudes and subjective norms towards people’s intentions to use public transportation. The results from this study provide valuable insights for transportation authorities to develop effective strategies to manage traffic during the spread of disease for a possible future epidemic.

Introduction The COVID-19 pandemic has been extremely disturbing mobility behavior due to travel restrictions and perceived COVID-19 threats. Recently, researchers from developed countries have shown interest in quantifying the impacts of the COVID-19 on individuals' mobility; however, similar research themes in lower income developing countries like Pakistan have not been sufficiently explored. Therefore, the objectives of the study are; 1) to explore the changes in self-reported individual's mobility behavior—trip frequencies by mode and by purpose in three COVID-19 severity periods; 2) to quantify the effects of respondents' personal (i.e., age, gender, education, and living place), and perceived details (i.e., safety perceptions, the COVID-19 threat perceptions) on the change in mobility behavior in the COVID-19 severity change; 3) to analyze the willingness to use public transportation in the post-pandemic period. Methods: A web-based questionnaire survey was conducted from September 2020 to November 2020, resulting in 565 responses. Descriptive analysis, random parameter bivariate probit modeling, and structural equation modeling are adopted to achieve the objectives. Results: The results reflect the change in individuals' mobility behavior in three severity periods of COVID-19, including before outbreak, during the most serious period, and after the most serious period. A substantial reduction in individuals' mobility was observed during the most serious period, which is recovering back to normal. The results also indicate the relationship of individuals' personal and perceived characteristics with the change in mobility in COVID-19 severity changes from before-to-serious and from the serious-to-after most serious period. Conclusion: The COVID-19 pandemic has been affecting individuals' mobility behavior in Pakistan. The study's findings provide insightful information for the transportation agencies to better prepare for sustainable transportation management in the post-pandemic era.

Background: Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy.Methods: RESTART was a prospective, randomised, open-label, blinded-endpoint, parallel-group trial at 122 hospitals in the UK that assessed whether starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. For this prespecified subgroup analysis, consultant neuroradiologists masked to treatment allocation reviewed brain CT or MRI scans performed before randomisation to confirm participant eligibility and rate features of the intracerebral haemorrhage and surrounding brain. We followed participants for primary (recurrent symptomatic intracerebral haemorrhage) and secondary (ischaemic stroke) outcomes for up to 5 years (reported elsewhere). For this report, we analysed eligible participants with intracerebral haemorrhage according to their treatment allocation in primary subgroup analyses of cerebral microbleeds on MRI and in exploratory subgroup analyses of other features on CT or MRI. The trial is registered with the ISRCTN registry, number ISRCTN71907627.Findings: Between May 22, 2013, and May 31, 2018, 537 participants were enrolled, of whom 525 (98%) had intracerebral haemorrhage: 507 (97%) were diagnosed on CT (252 assigned to start antiplatelet therapy and 255 assigned to avoid antiplatelet therapy, of whom one withdrew and was not analysed) and 254 (48%) underwent the required brain MRI protocol (122 in the start antiplatelet therapy group and 132 in the avoid antiplatelet therapy group). There were no clinically or statistically significant hazards of antiplatelet therapy on recurrent intracerebral haemorrhage in primary subgroup analyses of cerebral microbleed presence (2 or more) versus absence (0 or 1) (adjusted hazard ratio [HR] 0·30 [95% CI 0·08–1·13] vs 0·77 [0·13–4·61]; pinteraction=0·41), cerebral microbleed number 0–1 versus 2–4 versus 5 or more (HR 0·77 [0·13–4·62] vs 0·32 [0·03–3·66] vs 0·33 [0·07–1·60]; pinteraction=0·75), or cerebral microbleed strictly lobar versus other location (HR 0·52 [0·004–6·79] vs 0·37 [0·09–1·28]; pinteraction=0·85). There was no evidence of heterogeneity in the effects of antiplatelet therapy in any exploratory subgroup analyses (all pinteraction>0·05).Interpretation: Our findings exclude all but a very modest harmful effect of antiplatelet therapy on recurrent intracerebral haemorrhage in the presence of cerebral microbleeds. Further randomised trials are needed to replicate these findings and investigate them with greater precision.Funding: British Heart Foundation.

WOS: 000365465700025, Field screening of six groundnut cultivars (BARD-92, BARD-699, BARD-479, BAIU-2000, Golden and Chakori) in randomized complete block design with three replications was conducted against red hairy caterpillar (RHC), Amsacta albistriga (Walker), population in relation to leaf infestation, physico-morphic characters (leaf area and plant height), abiotic factors (temperature, rainfall and humidity) and their ultimate impact on yield. Highest RHC population and leaf infestation was observed on BARD-699 and the lowest on BARD-479 throughout the season. Irrespective of plant height, leaf area seemed to effect insect infestation with minimum infestation on BARD-479 with maximum leaf area while minimum was observed on BARD-699 (maximum insect infestation). The plant height of BARD-699 was found to be maximum, whereas minimum plant height was observed on BARD-479. Maximum pod yield was recorded on Bard-479 and minimum of Bard-699. The order of cultivar resistance against RHC population during the whole crop duration was BARD-479 < BARI-2000 < Golden < BARI-92 < Chakori < BARD-699. RHC population showed significant and positive correlation with leaf infestation, and non-significant and negative correlation with leaf area. Non-significant and positive correlation was found among RHC population and plant height, and significant but negative relationship was noted between mean temperature and RHC population. Although effect of rainfall was significant and positive on RHC population, there was significant and positive correlation between relative humidity and population of RHC. A significant and negative correlation between RHC population and yield was recorded. Based on the results, high yielding cultivar Bard-479 was found resistant and low yielding Bard-699 was found susceptible against RHC.

Major cities in Pakistan are experiencing rapid growth of urban population, resulted in high energy demand and viable severe energy crisis.In this regard, easy retrieval of solar energy can play a pivotal role to cater the mounting demand of energy. Solar energy can be said as a topographical asset of Pakistan; but still,a low adoption of this environment-friendly source was observed by countrymen. Residential units are one of the major consumers of energy. Thus, public opinion can be considered as a key factor to judge the perception of renewable energy in any society. Therefore, it is obligatory to adopt the practices, which could explore the acceptance of renewable clean energy sources. Hence, the purpose of this study is to deliver empirical data about the social acceptance of clean energy, i.e. solar panels, by discovering the public opinion about solar energy. Hyderabad, Pakistan was selected as a case study. The Facebook-based Questionnaire Survey was adopted to procure data, and the sample size was determined with the help of Taro method. This study is imperative in a sense that it can be important for policy makers to have a precise knowledge about public perceptions towards solar energy. By investigating the public attitudes towards consumption of solar energy; it becomes easier to comprehend the future of solar energy practice in Sindh province, particularly in Hyderabad, Pakistan.

In unpolluted areas the log-normal distribution of individuals per species fits well data from many benthic communities. Using a simple plotting method, under slight pollution the data show a distinct break in the normally straight line log-normal plot and the plot covers more geometric classes than data from unpolluted areas. Under more severe pollution stress the data show a return to a log-normal distribution, but with a shallower slope, and span more geometric classes than data from less polluted areas. The above-mentioned patterns are consistent for spatial effects of pollution in Oslofjord and for temporal effects in data from a Scottish sea loch and also apply to other communities. An explanation of the reasons for such patterns is given and consideration given to the robustness of and application of the methods described.

The macrobenthic fauna of the organically enriched Oslofjord was sampled in Sept.–Nov. 1977. Seventy-six stations were sampled using a stratified random plan. A total of 146 species were identified, dominated by polychaetes, molluscs and echinoderms. The faunal data were analysed by a variety of methods including diversity indices, log-normal distribution of individuals among species, factor analysis and numerical classification. The primary aim was the detection of pollution-induced disturbance and to delimit the extent of pollution on the benthic fauna of Oslofjord. All of the methods used showed a gradient from heavy pollution at the innermost part of the fjord where few species occurred, together with high dominance and low diversity, to normal unpolluted conditions at the Drobak sill with high species diversity. From the classification analysis a combination of both site and species data revealed a trend in species groupings which were broadly similar to data from other Scandinavian fjords and from Scotland. Hydrographical and biological data taken at the turn of the century and in the 1960's compared with the present data show declining conditions in Oslofjord, due primarily to organic enrichment combined with a naturally poor water exchange which leads to stagnation of the water mass.