CHEMICAL-CHANGES IN SIMULATED RAINDROPS FOLLOWING CONTACT WITH LEAVES OF 4 BOREAL FOREST SPECIES
CHEMICAL-CHANGES IN SIMULATED RAINDROPS FOLLOWING CONTACT WITH LEAVES OF 4 BOREAL FOREST SPECIES
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DOI：
10.1139/b88-332
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发表时间：
1988-12-01
期刊：
影响因子：
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通讯作者：
HUTCHINSON, TC
中科院分区：
文献类型：
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作者：
GABER, BA;HUTCHINSON, TC
模拟雨滴的pH值为5.6或3.2喷洒在四个北方森林植物物种在原位，随后从他们的叶片收集雨滴进行化学分析。其目的是更好地了解叶中和酸性雨滴的变化。种有山茱萸、野葱木、加拿大野百合和穗花槭。样品进行了分析的Ca ~（2+），Mg ~（2+），Na ~+，K ~+，NH ~（4+），PO ~（43-），NO ~（3-），Cl ~-和F ~-，以及pH值。叶雨滴离子浓度的变化较大时，喷雾与pH值3.2比与pH值3.2比与pH值5.6雨。离子浓度的增加和减少被发现，分别表示浸出和（或）溶解的颗粒物的叶子或保留冠层。离子浓度的快速变化表明表面沉积物在叶雨滴中和中起着重要作用。雨滴中[Ca 2 +]和[Mg 2 +]的增加与更大的中和作用是阳离子交换也可能发生的证据（r2 = 0.170和0.321，分别在pH 3.2; p < 0.01）。[H+]的变化与[NO3-]、[SO 42-]和[NH 4 +]的变化呈显著负相关（在pH 3.2时，r2分别为0.562、0.525和0.297; p < 0.01）。大多数测量的其他离子也显示出与[H+]变化的显著相关性，但通常相关性只能解释观察到的结果的一小部分（低r2）。还测量了干沉积。
Simulated raindrops of pH 5.6 or 3.2 were sprayed on four boreal forest plant species in situ, and raindrops were subsequently collected from their leaves for chemical analysis. The purpose was to understand better the changes involved in foliar neutralisation of acidic raindrops. The species usd were Cornus canadensis, Aralia nudicaulis, Maianthemum canadense, and Acer spicatum. Samples were analysed for Ca2+, Mg2+, Na+, K+, NH4+, PO43-, NO3-, Cl- and F-, as well as pH. Changes in leaf raindrop ion concentrations were greater when sprayed with the pH 3.2 than with the pH 3.2 than with the pH 5.6 rain. Both increases and decreases in ion concentration were found, indicating leaching and (or) dissolution of particulates on the leaf or retention by the canopy, respectively. Rapid changes in ion concentrations suggest surface deposits play an important role in leaf raindrop neutralisation. Increases in [Ca2+] and [Mg2+] in raindrops with greater neutralisation are evidence that cation exchange may also be occurring (r2 = 0.170 and 0.321, respectively, at pH 3.2; p < 0.01). There were significant negative correlations between changes in [H+] and changes in [NO3-], [SO42-], and [NH4+] (r2 = 0.562, 0.525, and 0.297, respectively, at pH 3.2; p < 0.01). Most of the other ions measured also showed significant correlations with changes in [H+], but generally the correlation could account for only a small percentage of the observed results (low r2). Dry deposition was also measured.