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高山森林生态系统氮和磷可随溪流非木质残体的输出和降解而流失,进而影响下游水体环境,但目前缺乏必要关注.因此,本文以岷江上游高山森林为研究对象,于2013年8月(雨量最大季节)调查了18条溪流中的非木质残体(树皮、树叶和<1 cm树枝)氮和磷贮量特征.结果表明,该区域溪流中非木质残体氮在单位面积集水区的贮量为2684 mg·hm-2,在单位面积溪流的氮贮量为774 mg·m-2,其中,树皮、树叶和<1 cm树枝在单位面积溪流的贮量分别为112、154和508 mg·m-2,分别占总氮贮量的14%、20%和66%;溪流中非木质残体磷在单位面积集水区的贮量为468 mg·hm-2,在单位面积溪流的磷贮量为135 mg·m-2,其中,树皮、树叶和<1 cm树枝在单位面积溪流的贮量分别为15、31和89mg·m-2,分别占总磷贮量的11%、23%和66%.回归分析结果表明,非木质残体氮和磷贮量均随溪流长度和面积的增加而显著增加,但随溪流流量的增加表现为先增加再降低的趋势.这些结果为深入认识岷江上游高山森林氮和磷流失途径及其对下游生态系统的潜在影响提供了新的思路.
In the alpine forest ecosystem, nitrogen and phosphorus can be lost with the output and degradation of non-woody debris in streams, and then affect the environment of downstream water bodies, but there is no necessary attention now.Therefore, in this paper, the alpine forest in the upper reaches of Minjiang River was studied, (Maximum season of rainfall), nitrogen and phosphorus storage characteristics of non-wood residues (barks, leaves and <1 cm branches) in 18 streams were investigated.The results showed that the non-woody residues in the streams in the unit area The water storage area was 2684 mg · hm-2, and the nitrogen storage per unit area of the stream was 774 mg · m-2, of which bark, leaves and branches with <1 cm branches per unit area were 112 , 154 and 508 mg · m-2, accounting for 14%, 20% and 66% of the total nitrogen storage respectively. The phosphorus content of non-wood residue phosphorus in the catchment per unit area in the stream was 468 mg · hm-2, The reserves of phosphorus in the stream area per unit area were 135 mg · m-2, of which the stocks of bark, leaves and branches <1 cm in unit area were 15, 31 and 89 mg · m-2, The results of regression analysis showed that the N and P storage of non-wood residues increased significantly with the increase of stream length and area, but with the increase of stream flow The increase in performance for the first increase and then decrease. These results for the upper reaches of Minjiang alpine forest-depth understanding of nitrogen and phosphorus loss pathways and their potential impact on the downstream ecosystem provides a new way of thinking.