Spatial and temporal variability of nitrate concentration in seepage water under a mature Norway spruce [Picea abies (L.) Karst] stand before and after clear cut

摘要: The spatial and temporal variability of the nitrate (NO3−) concentration in seepage water below main rooting zone a mature spruce forest was investigated using 121 suction cups which were implemented 2 × m grid at 40 cm depth mineral soil. Seepage collected least monthly during vegetation period 2005. In January 2006 clear cut performed on plot with 118 cups. Conventional geostatistical methods used to investigate NO3−. We tried explain observed multiple classification analysis (MCA) linear regression models (MLR) based vegetation, stand soil parameters, could be measured without disturbance ecosystem. NO3− reached mean values up 35.2 mg l−1 per sampling date distributions positively skewed. much lower than variability. showed structural patterns over whole period. Spatial autocorrelation ranged between 16 19 variance 65% 80% model semivariance. However, for practical purposes it should sufficient consider an range about 12 as last 5–6.5 only explained 5% total water. Vegetation parameters such distance size trees surrounding measuring points 40% MCA MLR models. After cut, means 10 spring but increased more then 150 until December 2006. distribution nearly normal. reversed compared stand. Structuring less pronounced ranges decreasing from April 3 following structuring 30% most dates. Thickness humus layer amount bottles, not considered stand, contributed significantly explanation after cut. Together coverage consequences future investigations are discussed.