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本文探讨了挪威南部两个大的流域内氮负荷对淡水和海水的影响。较大地区的氮固留的变化将强烈影响淡水中的氮的浓度和海水中氮的负荷并导致水体富营养化。大气沉降的增加、水文条件的改变、由于氮“饱和”或酸化对植物根系的损害造成植物对氮吸收量的减少都会促进富营养化作用。气候的波动强烈影响季节经流模式。较长期的气候变化将会造成大量有机氮矿质化的增加。生物可利用性和季节模式以及营养物质的比率将是决定受者反应的主要决定因素。对于人烟稀少的石南荒地占优势的Bjerkreim流域,营养元素的比例强烈趋向于高氮/磷比。磷元素浓度远远低于淡水富营养化所需浓度,氮的增加只会进一步加强流行的磷的制约性。类似的情况还会出现在海域。流入海洋的河流中氮相对于磷或硅过量而导致近岸海区磷或硅成为暂时性的制约因素。Auli河流集约农业活动产生了高氮、磷输出的但很分散、很难预测的具有可变氮/磷比的径流峰。相对于海水中的氮或磷浓度而言,Bjerkreim河低浓度的矿物质养分意味着稀释在起着作用。而Auli河流域可能在河水和峡湾内部形成富营养化。由于营养物质浓度显著的季节性变化和岸流的作用,河源对营养物质的影响将在夏季达到最大。来自两个流域及其子流域的数据表明农业活动对氮流失的整体重要性。
This article explores the impact of nitrogen load on freshwater and seawater in two large watersheds in southern Norway. Changes in nitrogen retention in larger areas will strongly affect nitrogen concentration in freshwater and nitrogen load in seawater and lead to eutrophication of the water body. Increases in atmospheric deposition and changes in hydrological conditions promote plant eutrophication by reducing nitrogen uptake due to damage to plant roots due to nitrogen saturation or acidification. Climate fluctuations strongly influence the seasonal flow pattern. Longer-term climate change will result in an increase in the mineralization of large amounts of organic nitrogen. Bioavailability and seasonal patterns as well as nutrient ratios will be the major determinants of the recipient’s response. For the sparsely populated Bjerkreim catchment in the Heathland, nutrient elements tend to have a high N / P ratio. Phosphorus concentration is far below the concentration required for freshwater eutrophication, and an increase in nitrogen will only further strengthen the control of the prevailing phosphorus. A similar situation will appear in the sea. The influx of nitrogen into rivers in the ocean is a temporary constraint on phosphorus or silicon in coastal waters relative to that of phosphorus or silicon. Auli River Intensive agricultural activity produces a runoff peak with a variable nitrogen / phosphorus ratio that is highly dispersed but unpredictable in high N and P output. The low concentration of mineral nutrients in the Bjerkreim River means that dilution plays a role, relative to the nitrogen or phosphorus concentration in seawater. The Auli River basin may be eutrophic within rivers and fjords. Heyuan’s nutrient impact will reach its maximum in the summer due to seasonal changes in nutrient concentrations and shoreline effects. Data from the two basins and their sub-basins show the overall importance of agricultural activities to the loss of nitrogen.