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Natural nanoparticles play important roles in the soil,sediment and water,which can not only adsorb certain metal ions effectively,but also influence the solubility,transportation and environmental behavior of contaminants in the environment.However,the previous and recent studies mainly focused on the engineering nanoparticles and soil colloids.The biogeochemical behavior of natural nanoparticles (e.g.stability,aggregation and transportation etc.) and its regulatory effects on the transport of nutrients and pollutants in soils is still poorly understood.Based on the ultrasonic-centrifugal method,the natural nanoparticles (<100nm) were dispersed and extracted from a zonal soil in China (collected from Jilin Province).The size of nanoparticles was measured using Transmission Electron Microscope.Results from the Dynamic Light Scattering analysis showed that the ionic strength played an important role in stability of the natural nanoparticles.The stability of the natural nanoparticles decreased with increasing the concentration of the electrolyte.Moreover,the stability of the natural nanoparticles was influenced by the valence of ions.The critical coagulation concentrations were 76.47 mM,1.15 mM and 0.05 mM for Na+,Ca2+ and La3+ respectively,followed with the Schulze-Hardy Rule of DLVO theory.It indicated that the DLVO theory may be extendedly used to describe the variation of stability for soil natural nanoparticles in environment.