Speciesα-diversity promotes butβ-diversity restricts aboveground biomass in tropical forests,depending on stand structure and environmental factors

Forest plays a vital role in the global biogeochemical cycles through a high rate of carbon sequestration and harboring biodiversity.However,local species diversity is declining while also becoming increasingly homogenized across communities.Although eff ects of local biotic processes(e.g.,speciesα-diversity and stand structural heterogeneity)and environmental factors on aboveground biomass(AGB)have been widely tested,there is a huge knowledge gap for the eff ect of regional biotic processes(i.e.,taxonomic and functionalβ-diversity)in forests.Here,we hypothesized that regional and local environmental factors along with biotic processes jointly regulate AGB through species shifts in tropical forests.Using piecewise structural equation modeling(pSEM),we linked climatic water availability,soil fertility,stand structural heterogeneity(either tree DBH inequality,height inequality,or stand density),speciesα-diversity,taxonomic or functionalβ-diversity(and its two components;β-turnover andβ-richness),and AGB across 189 inventory plots in tropical forests of Sri Lanka.Soil fertility and climatic water availability shaped local and regional biotic processes.Stand structural heterogeneity promoted speciesα-diversity but declinedβ-diversity(but increasedβ-taxonomic turnover).Speciesα-diversity and stand structural heterogeneity promoted AGB whereas taxonomic and functionalβ-diversity declined(butβ-taxonomic turnover increased)AGB.The relationships of AGB with speciesα-diversity andβ-diversity varied from signifi cant to nonsignifi cant positive depending on the specifi c combinations of stand structural heterogeneity metrics used.This study shows that local biotic processes could increase AGB due to the local and regional niche complementarity eff ect whereas the regional biotic processes could restrict AGB due to the regional selection or functional redundancy eff ect under favorable environmental conditions.We argue that biotic homogenization,as well as drought conditions,may have strong divergent impacts on forest functions and that the impacts of tree diversity loss may greatly reduce carbon sequestration.

Correction to:Speciesα-diversity promotes butβ-diversity restricts aboveground biomass in tropical forests,depending on stand structure and environmental factors

Correction to:J.For.Res.https://doi.org/10.1007/s11676-022-01560-8 During production process,the below mentioned errors appeared in the original article and inadvertently published with error.

Comparison of nitrous oxide(N2O)emissions calculations at a Swedish wastewater treatment plant based on water concentrations versus off-gas concentrations

Total nitrous oxide(N_2O) emissions from a conventional active sludge process were calculated using a mathematical emission model and dissolved N_2O in the water phase by a N_2O water sensor. Calculated emissions showed good agreement with measured emissions based on concentrations and air?ow in the off-gas ventilation system from the covered process. Various tests for a wide range of potentially affecting parameters indicated robust and reliable emission estimations by the model. Thus, common uncertainties in input data would still provide good emission estimations. Measurements of dissolved N_2O required low maintenance and N_2O emission monitoring based on such measurements might therefore be considered as a signi?cant practical improvement. This would be advantageous especially in non-enclosed wastewater treatment plants(WWTPs) otherwise requiring complex off-gas measurements. As the sensor is connected directly to the WWTPs monitoring and control system, emissions calculations could be incorporated.

海事能源转型:未来燃料和未来排放

The lifecycle greenhouse gas(GHG)emissions(Well-to-Wake)from maritime transport must be reduced by at least 50%in absolute values by 2050 to contribute to the ambitions of the Paris Agreement(2015).A transition from conventional fuels to alternative fuels with zero or lower GHG emissions is viewed as the most promising avenue to reach the GHG reductions.Whereas GHG and toxic pollutants emitted from the use of fossil fuels(heavy fuel oil(HFO)and marine gas/diesel oil(MGO/MDO))are generally well understood,the emissions associated with the new fuel options are only now being measured and communicated.This review provides an outlook on fuels that could help shipping respond to the decarbonization effort including Liquefied Petroleum Gas(LPG),Liquefied Natural Gas(LNG),methanol,ammonia,and hydrogen.A quantification of the pollutants associated from the use of these fuels is provided and challenges and barriers to their uptake are discussed.

甲醇燃料的船用发动机对空气排放的测量

Emissions of exhaust gases and particulate matter from a dual fuel marine engine using methanol as fuel with marine gasoil as pilot fuel have been examined for a ferry during operation.The emission factor for nitrogen oxides is lower than what is typically found for marine gasoil but does not reach the tier III limit.The emissions of particulate matter are significantly lower than for fuel oils and similar to what is found for LNG engines.The main part of the particles can be found in the ultrafine range with the peak being at around 18 nm.About 93%of the particles are evaporated and absorbed when using a thermodenuder,and thus a large majority of the particles are volatile.Methanol is a potential future marine fuel that will reduce emissions of air pollutants and can be made as a biofuel to meet emission targets for greenhouse gases.

Impact of Aromatic Concentration in Marine Fuels on Particle Emissions

The fuel sulfur content in marine fuels has been regulated in Sulfur Emission Control Areas(SECAs) since January 2015. However, other fuel characteristics are also believed to have an impact on particle emissions, particularly on the number of particles emitted. This study investigates the impact of the content of aromatics in fuel. To achieve fuel blends with concentrations of aromatics similar to those found in marine fuel oils, i.e. 20%–30% by volume(%vol.), normal diesel oil(4%–5% vol. aromatics) is doped with a mixture of aromatics. Emission measurements are conducted in test-bed engine facilities and particle emissions over a wide size range are analyzed. Results show a decreased number of particles emitted(or not change) with an increase in the aromatic concentration in fuel. This is because there is a reduction in the cetane number of the fuel with an increased aromatic content, which effects the combustion process and results in decreased particle formation. However, when ignition improver is used to increase the cetane number, particle emissions remain at a lower level than for normal diesel oil; thereby emphasizing the presence of other factors in the formation of particles.

A Method for Detection of Trace Concentrations of Underivatized Amino Acid in Hydrothermal Fluids by Ion-Pairing Reversed-Phase UPLC-ESI-QTOF-MS

Investigation of amino acids in hydrothermal systems is of prime importance for the understanding of geochemistry and microbiology of hydrothermal vents and plumes, for carbon and metals global cycles, for metabolism of some hydrothermal microorganisms and for the origin of life issue. Extensive theoretical and experimental work on amino acids behaviour in hydrothermal fluids has been done, conversely only few data exist on natural samples. Because each hydrothermal vent is unique, the more data we collect the better we will be able to address each of these questions. Usually amino acids in hydrothermal fluids have been measured by HPLC-FLD. The chromatographic separation was at least 26 min and up to 135 min and the required derivatization step may be time consuming, may use harmful chemicals and may be source of contamination. Alternatively, we describe here a method combining quickness (4.5 min), high resolution (10,000), very low LOD (sub-ppb) and without derivatization. Characterisation and separation of 10 relevant proteinogenic underivatized amino acids was achieved by ion-pairing reversed-phase Ultra-high Performance Liquid Chromatography-Electrospray Ionisation-Quadrupole Time of Flight-Mass Spectrometry (UPLC-ESI-QTOF-MS). Excellent linearity in the response was obtained for all amino acids with correlation coefficients > 0.9921. This method was successfully applied to natural hydrothermal fluid samples from ultramafic-hosted vents of the Mid-Atlantic Ridge region. Results are consistent with the only 2 other studies published on ultramafic-hosted vents and complete the few available data.

汞污染渔业的恢复

本文中,我们综合了有关生态系统无机汞(Hg)载荷变化与鱼体内甲基汞(MeHg)浓度之间联系的现有信息。尽管人们普遍假定水生生态系统汞载荷的增加导致鱼体内甲基汞浓度的增加,验证这一假定的定量数据尚很有限。这里,我们研究了源于一系列出处的现有证据:关于被工业排放物污染的生态系统的研究;关于鱼类甲基汞对大气载荷的响应的观测资料;跨越空间和环境梯度的研究以及实验操作。本文概述了目前对从汞载荷到鱼体甲基汞的运输和转化所涉及的主要过程的了解情况。还结合影响与鱼体内甲基汞响应的时机和大小有关的汞循环和生物积累的其他因素探讨了汞载荷的作用。所得出的主要结论是,汞载荷的变化(增加或减少)将引起鱼体内甲基汞的反应,这种反应的时间和大小将根据生态系统特有的变量和所添加的汞的形态而变化。

On the Importance of Sanitary Sewer Overflow on the Total Discharge of Microplastics from Sewage Water

The paper provides an investigation and understanding of the significance of various wastewater flows on microplastics retainment and emission to the environment. WWTPs and sewer overflows as an important pathway of microplastics to the environment are assessed by considering the removal of microplastics in WWTPs with different treatment processes and several sewer overflow types and their contribution to microplastic loads to recipients. On the example of the Baltic Sea basin, presented results indicate a considerable discharge of microplastic from WWTPs despite the relatively good overall removal efficiency. Results show that the discharge of microplastics from sewer overflows can be in the same magnitude as from treated wastewater although the total flow is much lower than that of treated wastewater. Sewer overflow events frequently occur and are expected to increase due to climate change and urbanization, unless infrastructure is adapted. At the same time, sewer overflows are often neglected in conventional wastewater handling.

恶劣暴风雨事件后森林土壤中汞和甲基汞的活动化

汞是空气、土壤、水和生物体中参与复杂生物地球化学循环的元素；由天然和人为因素引入。虽然汞是天然存在的元素，但是人类活动使全球环境中汞水平增加了1个数量级。人体通过工业、人为淘金、银汞合金和食用鱼类的途径暴露于汞。环境中汞的主要问题在于由于甲基汞的在淡水鱼中的生物富集效应导致鱼体中甲基汞浓度升高，达到了对人体健康有害的水平。

Halomethoxybenzenes in air of the Nordic region

Halomethoxybenzenes(HMBs)are a group of compounds with natural and anthropogenic origins.Here we extend a 2002e2015 survey of bromoanisoles(BAs)in the air and precipitation at Rå€o on the Swedish west coast and Pallas in Subarctic Finland.New BAs data are reported for 2018 and 2019 and chlorinated HMBs are included for these and some previous years:drosophilin A methyl ether(DAME:1,2,4,5-tetrachloro-3,6-dimethoxybenzene),tetrachloroveratrole(TeCV:1,2,3,4-tetrachloro-5,6-dimethoxybenzene),and pentachloroanisole(PeCA).The order of abundance of HMBs at Råo was SBAs>DAME>TeCV>PeCA,whereas at Pallas the order of abundance was DAME>SBAs>TeCA>PeCA.The lower abundance of BAs at Pallas reflects its inland location,away from direct marine influence.Clausius-Clapeyron(CC)plots of log partial pressure(Pair)/Pa versus 1/T suggested distant transport at both sites for PeCA and local exchange for DAME and TeCV.BAs were dominated by distant transport at Pallas and by both local and distant sources at Rå€o.Relationships between air and precipitation concentrations were examined by scavenging ratios,SR=(ng m^(-3))precip/(ng m^(-3))air.SRs were higher at Pallas than Rå€o due to greater Henry's law partitioning of gaseous compounds into precipitation at colder temperatures.DAME is produced by terrestrial fungi.We screened 19 fungal species from Swedish forests and found seven of them contained 0.01e3.8 mg DAME per kg fresh weight.We suggest that the volatilization of DAME from fungi and forest litter containing fungal mycelia may contribute to atmospheric levels at both sites.

Mass transfer of an organophosphate flame retardant between product source and dust in direct contact

Organophosphate flame retardants(OPFRs)are a group of semi-volatile organic compounds(SVOCs)and among the most abundant contaminants indoors.Their indoor presence has been associated with potential health risks however there is limited understanding as to how they are released from indoor sources.This study uses an emission micro-chamber to explore one of the currently understudied chemical migration pathways;direct transfer between a source material and settled dust in contact with the source.A tris(2-chloroisopropyl)phosphate(TCIPP)-treated insulation board is used as the source material.Rapid and substantial transfer was observed after only 8 h of source-dust contact,resulting in 80 times higher concentrations in dust compared to pre-experiment levels.Further time points at 24 h and 7 d showed similarly high average dust levels and the TCIPP in the dust and air in the chamber was calculated to be close to thermodynamic equilibrium.It was concluded that TCIPP was effectively transferred from the insulation board to the dust on its surface and the surrounding air via gas-phase diffusion.In a real room,a gradient of TCIPP concentrations in air above the surface of a product could result in higher concentrations in dust sitting on the product than dust in the rest of the room.

Direct GHG emissions from a pilot scale MBR-process treating municipal wastewater

To evaluate direct greenhouse gas emissions from Membrane Biological Reactor(MBR),measurements of nitrous oxide(N_(2)O)and methane(CH_(4))were made at a pilot-scale MBR treating municipal wastewater Measurements were conducted during two campaigns with some changes in processes,i.e.introducing a pre-aeration tank in the second measurement,different distributions of aeration in the treatment line,not the same wastewater inflow rate,two types of ultrafiltration membrane.It was found that about 0.004% and 0.07% of the total ammonium loads were emitted as N_(2)O,CH_(4) emissions were 0.026% and 0.12% of incoming TOC(0.008% and 0.04% of incoming COD)in 2014 and 2018.The obtained N_(2)O emission values were relatively low.The study suggested that a high aeration at the beginning of the treatment line may result in significantly high emissions of both N_(2)O and CH_(4).A significant change in aeration in the membrane ultrafiltration tank did not have the same impact.The MBR process is known for high quality effluent but have been questioned due to its higher carbon footprint due to energy consumption.This study gave a reference case about direct GHG emissions from MBR process and provide information for the further evaluation of MBR processes.