摘要
挪威南部气候的预期变化包括夏秋降水量的增加。这会影响土壤溶解有机物(DOM)的淋溶。本文评估了Storgama(59°0′N,海拔550～600m)小型源头集水区3年(2004～2006年)生长季中实验性增加降水(10mm/周)对总有机碳(TOC)和总有机氮(TON)淋溶的影响。额外降水(extra precipitation)对径流中TOC和TON平均浓度没有显著影响。所以,TOC和TON通量的增加几乎与水流量成比例。这说明,集水区土壤储存的吸附性和潜在移动性TOC和TON缓冲了径流中的DOM浓度。TOC和TON库的大小和动态依赖于生产和淋溶速度之间的平衡。罕见的短暂干旱对来自参照流域径流中的TOC和TON通量只有很小的影响。
Projected changes in climate in Southern Norway include increases in summer and autumn precipitation.This may affect leaching of dissolved organic matter (DOM) from soils.Effects of experimentally added extra precipitation (10 mm week^(-1)) during the growing season of 3 years (2004-2006) to small headwater catchments at Storgama (59°0′ N,550-600 m a.s.l.) on leaching of total organic carbon (TOC) and total organic nitrogen (TON) were assessed.Extra precipitation did not have a significant effect on average TOC and TON concentrations in runoff.Thus,fluxes of TOC and TON increased nearly proportionally with water fluxes.This suggests that a store of adsorbed and potentially mobile TOC and TON in catchment soils buffers the concentration of DOM in runoff.The size and dynamics of the pool of TOC and TON depends on the balance between production and leaching rates.Infrequent short droughts had only small effects on TOC and TON fluxes in runoff from the reference catchments.
