Effects of Dinitrogen-Fixing Trees on Phosphorus Biogeochemical Cycling in Contrasting Forests
Effects of Dinitrogen-Fixing Trees on Phosphorus Biogeochemical Cycling in Contrasting Forests
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DOI：
10.2136/sssaj1995.03615995005900050035x
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发表时间：
1995-09
影响因子：
2.9
通讯作者：
X. Zou;D. Binkley;B. Caldwell
中科院分区：
文献类型：
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作者：
X. Zou;D. Binkley;B. Caldwell
土壤中磷的有效性受地球化学和生物反应的控制。固氮树种与非固氮树种在凋落物产生和凋落物化学方面存在差异，这些差异可能会显著改变土壤磷的地球化学。我们研究了两种固氮树种对土壤不稳定磷库和潜在磷转化率的影响，并将这些变量与土壤酸性磷酸酶活性相关。试验处理包括固氮红桤木（Alnus rubra Bong.）针叶树和俄勒冈州的针叶和针叶混交林，以及固氮植物南方合欢（Albizia falcataria（L.）Fosberg，欧洲柳桉Eucalyptus saligna Sm.，而在夏威夷则是两者的混合。来自俄勒冈州的数据表明，红桤木增加了土壤活性有机磷（P0）水平和磷酸酶活性。红壤桤木和混交林土壤活性磷浓度是针叶林的2倍，混交林土壤活性无机磷（Pi）库和磷净溶解率是纯林的2 ~ 5倍，表明桤木和针叶林之间的相互作用而不是桤木的作用，触发了磷地球化学反应的变化.在夏威夷，两种纯A. falcataria和混交林比纯林高。萨利尼亚种植园。土壤酸性磷酸酶活性在纯A. falcataria种植园比纯E.萨利尼亚种植园。然而，不稳定的PI池和P转化率没有不同的三个夏威夷种植园。我们的研究结果表明，N2-fixWg树木增加土壤不稳定的P 0水平和土壤磷酸酶活性，而它们与非N2固定树木的相互作用因物种而异，并可能导致改变地球化学和生物P转化。
Phosphorus availability in soils is controlled by both geochemical and biological reactions. Dinitrogen-fixing trees differ from non-N 2 - fixing trees in litter production and litter chemistry, and these differences may substantially alter soil P biogeochemistry. We examined the effects of two N 2 -fixing tree species on labile P pools and potential P transformation rates and correlated these variables with soil acid phosphatase activity. Experimental treatments include stands of N 2 - fixing red alder (Alnus rubra Bong.), conifers, and a mixture of both in Oregon, and plantations of N 2 -fixing Albizia falcataria (L.) Fosberg, Eucalyptus saligna Sm., and a mixture of both in Hawaii. Data from Oregon indicated that red alder increased labile organic P (P 0 ) levels and soil phosphatase activity. Soil labile P 0 concentrations in the red alder and mixed stands were twice those of the conifer stand. Labile inorganic P (P i ) pools and net P solubilization rates in soils under the mixed stand were two- to fivefold greater than in pure stands, suggesting that interactions between alder and conifers, rather than alder's effect, triggered changes in P geochemical reactions. In Hawaii, labile P 0 concentrations in both pure A. falcataria and mixed plantations were higher than in the pure E. saligna plantation. Soil acid phosphatase activity in the pure A. falcataria plantation was twice as high as that in the pure E. saligna plantation. However, labile P i pools and P transformation rates did not differ among the three Hawaiian plantations. Our results suggest that N 2 -fixWg trees increase soil labile P 0 levels and soil phosphatase activities whereas their interactions with non-N 2 -fixing trees vary with species and may result in altering both geochemical and biological P transformations.