摘要
通过田间定位试验从生态系统的角度比较研究了中亚热带红壤低丘岗地几种主要旱坡地农田生态系统的水土流失、养分循环和平衡特征、土壤养分消长动态及空间分异，结果表明：水土流失是红壤旱坡地生态系统养分损失的重要途径之一，固体径流具有养分富集现象，速效养分损失以地表径流为主，水土流失养分损失量大小顺序为：有机碳＞全钾＞速效钾＞全氮＞全磷＞水解氮＞速效磷；免耕覆盖和垄作能显著减少水土流失及养分损失量；红壤旱地淋溶也是养分，尤其是氮素损失的重要途径；在养分平衡有盈余状况下，土壤养分水平是可以逐步提高的，其中，土壤速效磷、速效钾提高的速度较快，土壤全氮、有机质和全磷也有所提高，但仍处于较低水平；复合农林系统中，土壤养分存在明显的空间分异，农作物区域由于养分投入较高，土壤养分水平明显高于林木区域。
Soil and water loss is an important way of nutrients
loss.No tillage with mulching and ridge tillage can strongly decrease the loss of nutrients
caused by surface runoff and soil erosion.The potential of nutrient loss through erosion is as
follows:organic matter>total K>available K>total N>total P>hydrolysable N>available P.Strong
leaching in upland of red soil is also an important way of nutrients loss,especially for N.The
system with notillage and mulching has the largest surplus in comparison with other upland
ecosystems.Soil nutrient level can be increased gradually when the nutrient balance is in
surplus.Available P and K in soil would increase rapidly to a high level while total K decrease
slightly.Total N,P and organic matter in soil increase,but they still have low content.There is a
spatial variability of soil nutrients in agroforest ecosystems,soil nutrients in districts of
agricultural crops have higher level than that in district of trees.
出处
《生态学报》
CAS
CSCD
北大核心
1999年第3期335-341,共7页
Acta Ecologica Sinica
基金
国家"九五"攻关
关键词
红壤
旱坡地生态系统
养分循环
土壤养分
red soil,sloping
upland ecosystems,soil and water loss,nutrient cycling and balance,changes of soil nutrients
content.
