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在落叶松水曲柳纯林与混交林中,采集林地土和根际土,测定了氮、磷、钾浓度,目的是探讨养分条件变化在混交林增产上的作用。结果表明:混交林林地土全氮浓度和水解氮浓度与水曲柳纯林相近,但要高于落叶松纯林。水曲柳在混交林中根际土全氮和水解氮浓度与纯林中的相近,而落叶松在混交林中根际土水解氮浓度明显高于纯林中的。混交林林地土全磷和全钾浓度与两个树种的纯林相差不大。混交林林地土有效磷、有效钾浓度均高于水曲柳纯林,而且水曲柳在混交林中根际土的有效磷和有效钾浓度与纯林中的相比明显增加,分别高出44.1%~79.6%和13.5%~25.6%。这说明水曲柳在混交林中磷和钾的利用状况得到了改善。表2参15。
In pure Larch and mixed forest of Larix gmelini, forest soil and rhizosphere soil were collected, and the concentrations of nitrogen, phosphorus and potassium were determined. The purpose of this study was to explore the role of nutrient conditions in increasing the yield of mixed forest. The results showed that the concentrations of total nitrogen and hydrolyzed nitrogen in the mixed forest were similar to those in the pure stands but higher than those in the pure forests of Larix principis-rupprechtii. In the mixed forest, the concentrations of total nitrogen and hydrolyzed nitrogen in rhizosphere soil were similar to those in the pure forest, while the nitrogen concentration in the rhizosphere soil of the mixed forest was significantly higher than that in the pure forest. The contents of total phosphorus and total potassium in the mixed forests were similar to those of the two tree species. The content of available phosphorus and available potassium in mixed forests were higher than those in pure stands, and the effective and effective potassium concentrations of rhizosphere soil of manchurian ash were significantly higher than those in pure forests (44.1% 79.6% and 13.5% ~ 25.6%. This shows that Fraxinus mandshurica in the mixed forest phosphorus and potassium utilization has been improved. Table 2 Reference 15.