Optimization of Shanghai marine environment monitoring sites by integrating spatial correlation and stratified heterogeneity

The water quality grades of phosphate（PO4-P） and dissolved inorganic nitrogen（DIN） are integrated by spatial partitioning to fit the global and local semi-variograms of these nutrients. Leave-one-out cross validation is used to determine the statistical inference method. To minimize absolute average errors and error mean squares,stratified Kriging（SK） interpolation is applied to DIN and ordinary Kriging（OK） interpolation is applied to PO4-P.Ten percent of the sites is adjusted by considering their impact on the change in deviations in DIN and PO4-P interpolation and the resultant effect on areas with different water quality grades. Thus, seven redundant historical sites are removed. Seven historical sites are distributed in areas with water quality poorer than Grade IV at the north and south branches of the Changjiang（Yangtze River） Estuary and at the coastal region north of the Hangzhou Bay. Numerous sites are installed in these regions. The contents of various elements in the waters are not remarkably changed, and the waters are mixed well. Seven sites that have been optimized and removed are set to water with quality Grades III and IV. Optimization and adjustment of unrestricted areas show that the optimized and adjusted sites are mainly distributed in regions where the water quality grade undergoes transition.Therefore, key sites for adjustment and optimization are located at the boundaries of areas with different water quality grades and seawater.

Polyethylene imine functionalized porous carbon framework for selective nitrogen dioxide sensing with smartphone communication

Highly selective and remotely communicable nitrogen dioxide(NO_(2))sensing may contribute to future Internet of Things in environmental monitoring.However,room-temperature NO_(2)sensing materials such as carbon materials is still less than satisfactory due to their insensitive interaction with target gas.Here,polyethylene imine functionalized three-dimensional(3D)carbon framework(PEI/C framework)has been developed for enhanced selective NO_(2)sensing,via combined template synthesis and subsequent doping.Typically,the 3D PEI/C framework is observed porous shape with irregular coating.Beneficially,the response of C framework to NO_(2)increases while those of interfering gases decrease after being functionalized with PEI.Remarkably,the sensor prototypes show a 100 ppb-concentration detection limit at room temperature.Theoretically,such excellent NO_(2)sensing is attributed to the large specific surface ratio of porous 3D PEI/C framework,in which PEI serves as an active layer for target NO_(2),while a passivated one for interfering gases.Practically,such PEI/C framework sensor prototype is simulated for NO_(2)sensing device and communicated with a smartphone,showing great potential in future intelligent environmental monitoring.

Paving the way toward soil safety and health:current status,challenges,and potential solutions

Soil is a non-renewable resource,providing a majority of the world’s food and fiber while serving as a vital carbon reservoir.However,the health of soil faces global threats from human activities,particularly widespread contamination by industrial chemicals.Existing physical,chemical,and biological remediation approaches encounter challenges in preserving soil structure and function throughout the remediation process,as well as addressing the complexities of soil contamination on a regional scale.Viable solutions encompass monitoring and simulating soil processes,with a focus on utilizing big data to bridge micro-scale and macro-scale processes.Additionally,reducing pollutant emissions to soil is paramount due to the significant challenges associated with removing contaminants once they have entered the soil,coupled with the high economic costs of remediation.Further,it is imperative to implement advanced remediation technologies,such as monitored natural attenuation,and embrace holistic soil management approaches that involve regulatory frameworks,soil health indicators,and soil safety monitoring platforms.Safeguarding the enduring health and resilience of soils necessitates a blend of interdisciplinary research,technological innovation,and collaborative initiatives.

Evolution of drought and flood events on the Qinghai-Tibet Plateau and key issues for response

The Qinghai-Tibet Plateau is a climate-sensitive region.The characteristics of drought and flood events in this region are significantly different as compared to other areas in the country,which could potentially induce a series of water security,ecological and environmental problems.It is urgent that innovative theories and methods for estimation of drought and flood disasters as well as their adaptive regulations are required.Based on extensive literature review,this paper identifies new situations of the evolution of drought and flood events on the Qinghai-Tibet Plateau,and analyzes the research progress in terms of monitoring and simulation,forecasting and early warning,risk prevention and emergency response.The study found that there were problems such as insufficient integration of multi-source data,low accuracy of forecasting and early warning,unclear driving mechanisms of drought and flood disaster chains,and lack of targeted risk prevention and regulation measures.On this basis,future research priorities are proposed,and the possible research and development paths are elaborated,including the evolution law of drought and flood on the Qinghai-Tibet Plateau,the coincidence characteristics of drought and flood from the perspective of a water resources system,prediction and early warning of drought and flood coupled with numerical simulation and knowledge mining,identification of risk blocking points of drought and flood disaster chain and the adaptive regulations.Hopefully,the paper will provide technical support for preventing flood and drought disasters,water resources protection,ecological restoration and climate change adaptation on the Qinghai-Tibet Plateau.