Influence of phycospheric bacterioplankton disruption or removal on algae growth and survival

Phycospheric bacteria play a crucial role in the survival of microalgae. However, the potential of using the growth regulation and community structure modulation of phycospheric bacteria to prevent the occurrence of blooms is yet to be verified. The phycospheric bacterioplankton of Cyclotella sp. can be categorized into HNA (high nucleic acid) bacteria and LNA (low nucleic acid) bacteria. 16S rRNA sequencing showed that the HNA bacteria exhibited higher α-diversity compared to the LNA bacteria, and the microbial community composition also exhibited variations. Metagenomic sequencing further indicated the distinct ecological functions between HNA and LNA bacteria. Furthermore, the study showcased the restorative capacity of the phycospheric bacterioplankton. Biomass analysis revealed that the recovery of phycospheric bacterioplankton positively influenced the microalgae growth, thus affirming the significance of phycospheric bacterioplankton to microalgae. The community structure of phycospheric bacterioplankton demonstrated a notable decrease in the abundance of restored LNA core bacteria. Additionally, the restored phycospheric bacterioplankton exhibited a more complex co-occurrence network structure, resulting in decreased resistance and sensitivity of microalgae to adverse environments. The presence of phycospheric bacterioplankton provides a protective shield for microalgae, and thus destabilizing or removing phycospheric bacterioplankton may effectively inhibit growth of microalgae.

Quality analysis and categorisation of public space

Public spaces are considered areas that promote users' physical and mental health. The role of these people in public spaces makes it necessary to evaluate such areas. In this study, 12 urban parks on the island of Tenerife were evaluated, combining the assessment of a trained observer and the perception of users, to analyse and categorise the environmental quality of the parks. The findings of this study conclude that users are good evaluators of public spaces; that the Public Space Characteristics Observation Questionnaire (PSCOQ) tool allows the classification of public spaces and that physical order is capable of predicting the environmental quality and the restorative capacity of spaces, as perceived by users. The PSCOQ observation tool makes it possible to detect the strengths and weaknesses of public spaces so they can be improved and adapted to the needs of users.

Attractive running environments for all? A cross-sectional study on physical environmental characteristics and runners' motives and attitudes, in relation to the experience of the running environment

Background

Running has become one of the most popular sports and has proven benefits for public health. Policy makers are increasingly aware that attractively designed public spaces may promote running. However, little is known about what makes a running environment attractive and restorative for runners and to what extent this depends on characteristics of the runner. This study aims to investigate 1) to what extent intrapersonal characteristics (i.e. motives and attitudes) and perceived environmental characteristics (e.g. quality of the running surface, greenness of the route, feelings of safety and hinderance by other road users) are associated with the perceived attractiveness and restorative capacity of the running environment and 2) to what extent the number of years of running experience modify these associations.

Methods

Cross-sectional data were collected through the online Eindhoven Running Survey 2015 (ERS15) among half marathon runners (N = 2477; response rate 26.6%). Linear regression analyses were performed for two outcomes separately (i.e. perceived attractiveness and perceived restorative capacity of the running environment) to investigate their relations with motives and attitudes, perceived environmental characteristics and interactions between perceived environmental characteristics and number of years of running experience.

Results

Perceived environmental characteristics, including green and lively routes and a comfortable running surface were more important for runners’ evaluation of the attractiveness and restorative capacity of the running environment than runners’ motives and attitudes. In contrast to experienced runners, perceived hinder from unleashed dogs and pedestrians positively impacted the attractiveness and restorative capacity for less experienced runners.

Conclusions

Perceived environmental characteristics were important determinants of the attractiveness and restorative capacity of the running environment for both novice and experienced runners. However, green and lively elements in the running environment and hinderances by cars were more important for less experienced runners. In order to keep novice runners involved in running it is recommended to design comfortable running tracks and routes and provide good access to attractive, green and lively spaces.