Integrity and Size of Green Spaces Are Critical for the Functional Di-versity of Birds:Evidence from the Eastern and Northwestern Regions of China

Urbanization often changes bird species richness and affects the functional diversity.Therefore,understanding these changes helps city planners improve green space design and land use planning.Our study used multiple datasets to explore the effects of land-scape patterns and natural environments on the functional diversity of birds in urban parks and campuses in the eastern and northwest-ern regions of China.Firstly,we used the data to calculate birds of the functional richness(FRic),functional evenness(FEve),and func-tional divergence(FDiv)of 68 urban spaces in the eastern and northwestern regions of China.Further,we established generalized linear models of natural factors,human factors,and functional diversity.Results showed more bird species with unique traits were in the north-western region.This may be because the earlier urbanization in the eastern region filtered out urban-sensitive species,leaving behind urban adapters.Moreover,we found that the fractal dimension index was the most significant positive factor of FRic in the eastern re-gion but the most significant negative factor of FDiv.Elevation was the most significant negative influence factor of FEve in the eastern region,but it was the most potent positive influence factor of FRic in the northwestern region.Population density had a significant posit-ive effect on FDiv in the northwestern region.However,green space areas significantly negatively impacted FEve in the northwestern region.In addition,birds in parks in both regions had more functional traits than those on campuses,possibly because of the larger green space in parks,which may contain more fragments of native vegetation and reduce human interference.Our study suggests that pre-serving more original vegetation and reducing human disturbance in cities can increase the functional diversity of urban birds and im-prove urban ecosystem functions.

Discharge Distribution and Quality of Tail Water for Mariculture in Tianjin

[Objectives] This study was conducted to understand the pollution load of mariculture in Tianjin. [Methods] The tail water discharged by the main mariculture methods in Tianjin was monitored, and the tail water quality was evaluated. According to the aquaculture area and distribution and the discharge destination of the aquaculture tail water, a preliminary evaluation of the pollutant discharge situation was carried out, and different aquaculture methods were compared and analyzed for the differences in discharged pollutants. [Results] The main pollution factors in pond mariculture were chemical oxygen demand(CODMn), active phosphate and total phosphorus. The main pollution factors in factory mariculture were inorganic nitrogen, active phosphate and total nitrogen. Pond mariculture showed higher up-to-standard rates of inorganic nitrogen and active phosphate contents and lower up-to-standard rates of suspended solids, CODMn, and total phosphorus content than factory mariculture, and the up-to-standard rates of total nitrogen and total phosphorus contents in the flowing water type of factory mariculture were higher than those in the circulating water type. The discharge of pond mariculture was less than factory mariculture, and mariculture had the greatest impact on Fuzhuang Drainage Canal in that 92.3% of the total pollutant discharge monitored went to Fuzhuang Drainage Canal. The circulating water type could reduce pollutant discharge compared with the flowing water type of factory mariculture. [Conclusions] This study proposed countermeasures and suggestions for reducing pollution from marineculture.

Vertical distribution of volatile organic compounds conducted by tethered balloon in the Beijing-Tianjin-Hebei region of China

Volatile organic compounds(VOCs) as precursors of ozone and secondary organic aerosols can cause adverse effects on the environment and human health.However,knowledge of the VOC vertical profile in the lower troposphere of major Chinese cities is poorly understood.In this study,tethered balloon flights were conducted over the juncture of BeijingTianjin-Hebei in China during the winter of 2016.Thirty-six vertical air samples were collected on selected heavy and light pollution days at altitudes of 50-1000 meters above ground level.On average,the concentration of total VOCs(TVOCs) at 50-100 m was 4.9 times higher than at 900-1000 m(46.9 ppbV vs.8.0 ppbV).TVOC concentrations changed rapidly from altitudes of 50-100 to 401-500 m,with an average decrease of 72%.With further altitude increase,the TVOC concentration gradually decreased.The xylene/benzene ratios of 34/36 air samples were lower than 1.1,and the benzene/toluene ratios of 34/36 samples were higher than 0.4,indicating the occurrence of aged air mass during the sampling period.Alkenes contributed most in terms of both OH loss rate(39%-71%) and ozone formation potential(40%-72%),followed by aromatics(6%-38%).Finally,the main factors affecting the vertical distributions of VOCs were local source emission and negative dispersion conditions on polluted days.These data could advance our scientific understanding of VOC vertical distribution.

Elemental composition and risk assessment of heavy metals in the PM10 fractions of road dust and roadside soil

A total of 64 dust samples were analyzed to determine the size distribution and elemental composition of the PM10 fraction, including42 road dust(RD), 12 roadside soil(RSD), and 10 park road dust(PRD) samples. The mass of dust smaller than 20μm was dominated by particles sized 2.5-16 μm, which accounted for 85%, 88%, and 87% of the RD, PRD, and RSD, respectively. Additionally, crustal elements accounted for 30.14%, 36.35%, and 37.14% of the PMio fractions of the RD, RSD, and PRD, respectively. The most abundant trace elements in RD, RSD, and PRD were Zn, Mn, and Cu (range, 277 to 874 mg/kg). Moreover, the /geo values revealed all dusts were contaminated with Pb, Zn, Cu, Sb, Sn, and Cd. Health risk assessment showed that Mn, Ni, Cu, Zn, Cd, Sb, and Pb in the PM10 fraction of three types of dusts posed non-cancer risks to children but posed no non-cancer risk to adults. Additionally, As, Ni, and Cd posed no cancer risk to inhabitants.