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With the acceleration of urbanization throughout the world, climate problems related to climate change including urban heat islands and global warming have become challenges to urban human settlements. Numerous studies have shown that greenways are beneficial to urban climate improvement and can provide leisure places for people. Taking the coastal greenway in Qingdao as the research object, mobile measurements of the microclimate of the greenway were conducted in order to put forward an evaluation method for the research of outdoor thermal comfort. The results showed that different vegetation coverage affected the PET (physiologically equivalent temperature), UTCI (Universal Thermal Climate Index) as well as thermal comfort voting. We found no significant correlation between activities, age, gender, and thermal comfort voting. Air temperature sensation and solar radiation sensation were the primary factors affecting the thermal comfort voting of all sections. Otherwise, within some sections, wind sensation and humidity sensation were correlated with thermal sensation voting and thermal comfort voting, respectively. Both PET and UTCI were found to have a negative correlation with the vegetation coverage on both sides of the greenway. However, the vegetation coverage had positive correlation (R = 0.072) for thermal sensation and significant positive correlation (R = 0.077*) for thermal comfort. The paved area cover was found to have a positive correlation with PET and UTCI, while having a negative correlation with thermal sensation (R = −0.049) and thermal comfort (R = −0.041). This study can provide scientific recommendations for the planning and design of greenway landscapes to improve thermal comfort. [ABSTRACT FROM AUTHOR]

Imidacloprid and thiacloprid, two neonicotinoid insecticides that are extensively used in urban areas, are potentially toxic to non-target aquatic organisms. In this study, the concentrations of imidacloprid and thiacloprid in surface runoff after rainfall were 20.79–43.77 ng/L and 25.13–63.84 ng/L, respectively, whereas the levels for the Licun River were 10.78–41.70 ng/L and 2.66–39.68 ng/L, respectively. The acute and chronic criteria for imidacloprid and thiacloprid are 0.865, 0.006, 0.83, and 0.012 μg/L, respectively. Tiered ecological risk assessments revealed the chronic ecological risks of these micropollutants to local aquatic species. There was a moderate chronic toxicity risk associated with imidacloprid and thiacloprid in the Licun River, and the joint probability curves showed a probability of chronic ecological risk to 5 % of the aquatic organisms at 68 %–97 %. The results provide evidence of urban surface runoff transporting micropollutants from surface into rivers and estuaries, highlighting the ecological risks to aquatic ecosystems. • IMI and THI are discharged into the sea through rivers and surface runoff. • Hazardous concentration for 5 % of species was derived on acute and chronic data. • Aquatic ecological risk was conducted by joint probability curve method. • Ecological risk to aquatic species of two insecticides in Licun River is moderate. [ABSTRACT FROM AUTHOR]

Ships are considered important contributors to air pollution and have seriously health impact globally. Although many researchers have carried out studies on emission factors (EFs) in recent years, studies covering various types of ships are rare and the chemical characteristics of particulate matter (PM) emitted by them are unclear. Due to the diversity of different national fleets, the current emission inventory in China established by citing foreign EFs will lead to inaccurate calculation results and generate large uncertainty. In this study, the EFs for ocean-going, harbour, offshore and inland vessels were measured by the portable emission measurement system (PEMS). The specific compositions of PM were analyzed, including carbonaceous components, water-soluble ions (WSI), elements, and polycyclic aromatic hydrocarbons (PAHs). Combined with localized EFs, the ship emission inventory of Qingdao Port was established based on Automatic Identification System (AIS) data. The results show nitrogen oxide (NOx) is the primary pollutant discharged by all ships, followed by sulfur dioxide (SO 2). The emissions of SO 2 and PM from inland and offshore vessels fueled with high sulfur fuel (HSF) are significantly higher than other ships. Carbonaceous components accounted for 43.4%–53.9% of the total mass of PM, WSI accounted for 9.8%–14.3%, and elements accounted for 16.5%–28.6%. Although the use of low sulfur fuel (LSF) has reduced the emission of V and Ni from ships, it could still be treated as tracer elements of ship emissions. The annual emissions of SO 2 , NO X , PM 2.5 , THC and CO from ships in Qingdao port in 2020 were 9728.5, 38503.9, 1424.9, 1331.5 and 2440.4 tons, respectively. The ship emission inventory established based on EPA-recommended EFs resulted in underestimating approximately 16.8% of ship pollutants, especially for SO 2 and PM. Ocean-going ships and offshore vessels are major emitters in the study waters. This study is hoped to provide a valuable reference for the further regulation and policy formulation of ship emissions in China. [Display omitted] • On-board measurements were carried out on typical ships by PEMS. • EFs for gas pollutants and particle components of various vessel types are provided. • Fuel types have a significant impact on the particulate fraction of ships. • It reveals the current emissions from Chinese ships may be underestimated. • Approximately 16.8% of ship emissions in Qingdao Port are undervalued in 2020. [ABSTRACT FROM AUTHOR]

As the largest container port in northern China, the prosperous maritime trade has not only promoted the economic development of Qingdao port but also brought serious pollution to the air quality. Ship emissions have caused a significant influence on public health. The establishment of the Domestic Emission Control Area (DECA) is a key policy to reduce ship emissions in recent years. It has been implemented in Qingdao Port from January 1, 2019. To evaluate the environmental benefits of the DECA policy, this study established a bottom-up ship emission inventory in 2020 for Qingdao based on Automatic Identification System (AIS) data. Changes in ship emissions and their impact on air quality in Qingdao are evaluated for the same study area before and after the implementation of DECA policy. The total emissions in all study area for SO 2 , NO X , PM 10 , PM 2.5 , HC and CO in 2020 are 8.16 × 103, 3.31 × 104, 1.25 × 103, 1.15 × 103, 1.18 × 103, 2.15 × 103 tons (t), respectively, reductions of 67.9%, 15.4%, 63.2%, 62.9%, 27.2% and 23.2% compared with 2016, and reductions of 73.42%, 29.97%, 69.54%, 69.26%, 39.71%, 36.44% compared with the scenario without DECA in 2020. The inter-month change and spatial distribution of ship emissions are similar in both years. Shinan District, Shibei District and Huangdao District are most affected by ship emissions, with the largest influence in summer. The ship's contribution to air pollution in each area had been significantly reduced, especially for SO 2 and PM after DECA policy. However, the emission reduction of other pollutants is limited, so it is necessary to further enhance the DECA policy. Our research aims to conduct a comprehensive assessment of the environmental benefits for DECA policy, and provide support for the further improvement of the subsequent measures. [Display omitted] • High spatiotemporal resolution ship emission inventory for Qingdao in 2020 is updated. • Total ship emission in Qingdao during 2020 was 46,965.7 tons, 37.7% lower than 2016. • More than 50% of ship pollutants occur within the baseline of territorial sea. • Ship emissions in summer have the most significant impact on urban air quality. • DECA policy has reduced ship emission of SO 2 by 73.4% and PM 2.5 by 69.5%. [ABSTRACT FROM AUTHOR]

Chlorophyll-a (Chl-a) is an objective biological indicator, which reflects the nutritional status of coastal waters. However, the turbid coastal waters pose challenges to the application of existing Chl-a remote sensing models of case II waters. Based on the bio-optical models, we analyzed the suppression of coastal total suspended matter (TSM) on the Chl-a optical characteristics and developed an improved model using the imagery from a hyper-spectrometer mounted on an unmanned aerial vehicle (UAV). The new model was applied to estimate the spatiotemporal distribution of Chl-a concentration in coastal waters of Qingdao on 17 December 2018, 22 March 2019, and 20 July 2019. Compared with the previous models, the correlation coefficients ( R 2 ) of Chl-a concentrations retrieved by the new model and in situ measurements were greatly improved, proving that the new model shows a better performance in retrieving coastal Chl-a concentration. On this basis, the spatiotemporal variations of Chl-a in Qingdao coastal waters were analyzed, showing that the spatial variation is mainly related to the TSM concentration, wind waves, and aquaculture, and the temporal variation is mainly influenced by the sea surface temperature (SST), sea surface salinity (SSS), and human activities. [ABSTRACT FROM AUTHOR]