塞罕坝地区华北落叶松人工林土壤水肥变化规律的研究

通过对塞罕坝地区华北落叶松人工林不同年份、不同立地条件、不同土层土壤水肥含量的研究，分析了土壤的水肥变化规律，其结果表明，在生长季内，各层土壤含水量均经历了升高一降低一再升高的变化历程；林地存在土壤酸化、地力衰退现象。研究结果还发现，随林木成熟期的接近，林地速效氮含量整体下降明显。

Rules of water and fertilizer movement in the soil of Larix principis-rupprechtii man-made forests in Saihanbai area

The rules of water and fertilizer movement in the soil are analyzed by following different years,sites,content of water and fertilizer in different layers of soil in the Larix principis-rupprechtii man-made forests in Saihanbai area.The results show that during the growing season the water content in each layer of soil has an alternative course which is from increase to decrease and then increase again.Forestland exists the symptoms of soil acidification and soil productivity decrease.The content of readily...