Fertilizer 15N Fates of the Coastal Saline Soil-Wheat Systems with Different Salinization Degrees in the Yellow River Delta

In order to clarify the fates of fertilizer N in coastal saline soil-wheat systems with different salinization degrees, this study was conducted determine 15N uptake rates various parts wheat plant at maturity stage and residual three soils loss by using 15N-labeled urea tracing method Yellow River Delta. The results showed that: (1) increase soil salinity from 0.2% 1% promoted absorb not significantly inhibited dry matter mass accumulation uptakes each whole plant, but especially increased total concentration roots, stems, leaves, grains. aggravation enhanced distribution ratios Ndffs leaves depress salt stress. (2) residues were mainly concentrated 0~20 cm layer decreased as profile deepened 0 100 cm; 0~40 accumulated 40~100 degrees significantly. (3) applied system 1.53~13.96%, 10.05~48.69%, losses 37.35~88.42%, lowest utilization soils, highest rate lightly moderately heavily soils. inhibits intensifies 15N. Therefore, fate degree increased. conventional management that extremely inefficient for more should be optimized enhance efficiency yield