洪水沉积物对长江中游洪泛区土壤钾素营养的影响

本文对比研究了长江中游几类洪泛区 (江心洲、洲滩和圩垸等 )的洪水沉积物和剖面土壤的钾素营养状况。结果表明 ,相对于洪泛区耕层 (表层 )或剖面土壤的钾素状况 ,洪水沉积物的覆盖能丰富表土的钾素营养 ,显著增加表土的速效钾和缓效钾含量 ,且速效钾的增幅大于缓效钾 ,而对全钾无明显影响。沉积物对土壤钾素状况的影响与其颗粒组成、有机质含量、CEC和土地利用方式等因素有关。沉积物和土壤的钾素状况与粘粒含量 (<0 0 1mm)呈显著正相关 ,与砂粒部分呈负相关 ;有机质和CEC对土壤钾素的有效性有一定影响 ;而洪泛区土地利用方式与耕层土壤钾素的消耗有关

Effects of Flood Sediment on Soil Potassium Nutrition in the Flooded Area of the Middle Yangtze Valley

In order to study the influence of flood sediment on the soil potassium nutrition in the flooded area of the Yangtze Middle Reaches, the sediments and soils in three cross sectioned landscapes (river island, river beach, enclosed dike),are investigated in this paper. The reslt shows that the flood sediment can enrich potassium, especially the rapidly available potassium and slow release potassium. The sediment and soil potassium condition is related to some factors, such as granule size, organic matter content, CEC and land use means. The effect of granule size on potassium condition is controlled by the content of the clay particle content (<0 01mm). There is more potassium with more clay particle, and vice versa. Organic matter content and CEC also have some influence on soil potassium, showing significant positive relation with rapidly available potassium. The effects of land use on soil potassium reflect on consumption of soil potassium.