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Marjo Palviainen Leena Finér Ari Laurén Samuli Launiainen Sirpa Piirainen Tuija Mattsson Mike Starr 《Ambio》2014,43(2):218-233
The long-term impacts of current forest management methods on surface water quality in Fennoscandia are largely unexplored. We studied the long-term effects of clear-cutting and site preparation on runoff and the export of total nitrogen (total N), total organic nitrogen (TON), ammonium (NH4-N), nitrate (NO3-N), total phosphorus (total P), phosphate (PO4-P), total organic carbon, and suspended solids (SS) in three paired-catchments in Eastern Finland. Clear-cutting and soil preparation were carried out on 34 % (C34), 11 % (C11), and 8 % (C8) of the area of the treated catchments and wide buffer zones were left along the streams. Clear-cutting and soil preparation increased annual runoff and total N, TON, NO3-N, PO4-P, and SS loads, except for SS, only in C34. Runoff increased by 16 % and the annual exports of total N, TON, NO3-N, and PO4-P by 18, 12, 270, and 12 %, respectively, during the 14-year period after clear-cutting. SS export increased by 291 % in C34, 134 % in C11, and 16 % in C8 during the 14, 6, and 11-year periods after clear-cutting. In the C11 catchment, NO3-N export decreased by 12 %. The results indicate that while current forest management practices can increase the export of N, P and SS from boreal catchments for many years (>10 years), the increases are only significant when the area of clear cutting exceeds 30 % of catchment area. 相似文献
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Mika Nieminen Sirpa Piirainen Ulf Sikström Stefan Löfgren Hannu Marttila Sakari Sarkkola Ari Laurén Leena Finér 《Ambio》2018,47(5):535-545
The objective of this study was to evaluate the potential of different water management options to mitigate sediment and nutrient exports from ditch network maintenance (DNM) areas in boreal peatland forests. Available literature was reviewed, past data reanalyzed, effects of drainage intensity modeled, and major research gaps identified. The results indicate that excess downstream loads may be difficult to prevent. Water protection structures constructed to capture eroded matter are either inefficient (sedimentation ponds) or difficult to apply (wetland buffers). It may be more efficient to decrease erosion, either by limiting peak water velocity (dam structures) or by adjusting ditch depth and spacing to enable satisfactory drainage without exposing the mineral soil below peat. Future research should be directed towards the effects of ditch breaks and adjusted ditch depth and spacing in managing water quality in DNM areas. 相似文献
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