选用 3 种浓度铵态氮和总磷溶液, 分别以 01 67 L/ s、11 82 L/s 两种流量对河北省围场县落叶松林河岸缓冲带 进行灌水试验, 分析河岸缓冲带对不同浓度、不同流量地表径流中铵态氮、总磷的削减效果。结果表明, 随缓冲距离 增加, 河岸缓冲带对地表径流铵态氮和总磷削减效果呈增强趋势。在相同缓冲距离处, 较小地表径流量下对铵态氮 和总磷削减率普遍大于较大流量下的削减率。随着缓冲距离增大, 较小径流量下铵态氮削减率和较大流量下铵态 氮削减率的差值表现出先增大后减小的趋势。经 20 m 的落叶松林河岸缓冲带后, 地表径流量对各污染条件下铵态 氮和总磷削减率的影响逐渐变小。在两种径流量下, 落叶松河岸缓冲带对铵态氮和总磷的削减率都呈现出重度污 染削减率> 中度污染削减率> 轻度污染削减率的规律。

To fully understand the r eductio n effects of lar ch for est riparian buffer zones o n surface runoff po llutants, w e used am2 mo nium nitr og en and total pho sphor us so lutio ns o f three co ncentrations to irrig ate the larch fo rest riparian buffer zo ne in Weichang Count y of H ebei Pr ov ince at flow r ates o f 0. 67 L/s and 1. 82 L/s. The r esults show ed that the reduct ion effect of ri2 parian buffer zone on the ammonium nit rog en and total phospho rus in surface r unoff wo uld be enhanced w ith the increase of buffer leng th. At the same buffer distance in the riparian buffer zone, the reduction rates of ammonium nitrog en and to tal phos2 phor us in the smaller surface runo ff wer e bo th bet ter t han tho se in the larg er runo ff. With the increase of buffer dist ance, the differ ence of t he r eduction r ate o f ammonium nit rog en between smaller runoff and larg er runoff showed a trend of increasing first and then decr easing . When the polluted water flow ed throug h 20 m la rch for est riparian buffer zo ne, the influence of surface runo ff on the reductio n r ates of ammonium nitro gen and to tal pho sphor us became smaller in all t he po llution co ndit ions. At bo thruno ff vo lumes, the reductio n rat es of ammonium nitr og en and total phosphorus in the lar ch riparian buffer zo ne show ed the law s o f heav y pollutio n reductio n r ate > moderate pollutio n r eduction r ate > lig ht pollution r educt ion rat e.

河北省科技计划项目( 16223607D) ; 河北省水利科技计划项目( 2018210)