微塑料丰度与施氮量对土壤水氮运移特性的影响研究OA

To investigate the effects of microplastic abundance and nitrogen application rates on soil water nitrogen transport characteristics,a one-dimensional soil column simulation experiment was conducted indoors.The study examined the impact of two polyethylene microplastic abundances(low abundance 0.3%,A;high abundance 0.6%,B)and two nitrogen application rates(300,600 mg/L)on soil infiltration wet front,cumulative infiltra-tion volume,and nitrate nitrogen content,alongside two nitrogen-free treatments and a control group,totaling sev-en treatments.Simultaneously,soil profile moisture content was monitored.Soil moisture front advancement,cumu-lative infiltration volume,and nitrate nitrogen content were measured,while soil profile moisture content was mo-nitored and fitted to a moisture front advancement model and two primary infiltration models.Results indicated:under no nitrogen application,high microplastic abundance promoted soil water infiltration while low microplastic abundance slowed it;high nitrogen application generally enhanced infiltration,with low microplastic abundance showing superior infiltration capacity compared to high microplastic abundance,which exhibited stronger nitrogen retention;low nitrogen application generally inhibited infiltration.Low microplastic abundance exhibited greater infiltration inhibition than high abundance,yet demonstrated superior nitrogen retention capacity.The relationship between wetting front migration distance and time across treatments followed power-law functions,with both Kos-tiakov and Philip models effectively simulating cumulative infiltration under varying microplastic abundances and nitrogen application rates.