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幼林桉树施肥效应研究 总被引:4,自引:0,他引:4
2004年4月对种植在湘南蓝山县丘冈地红壤上的桉树进行了施肥试验。试验设施肥与不施肥(对照)2个施肥水平,施肥的设5个处理,3个重复。同年10月和次年4月分别对桉树的生长情况(树高和胸径)进行调查。结果如下:施肥前、施肥后5个月和施肥后12个月桉树5个施肥处理平均树高分别为2.34m、5.12m、5.40m,平均胸径分别为1.91cm,4.46cm、4.92cm;而同时期对照的树高分别为2.42m、4.08m、4.38m。胸径分别为1.87cm、3.46cm、3.82cm。施肥的比对照平均要多长高1.02m、胸径要多长粗1.1cm。4—10月的长势要比10月一次年4月大得多。由此可得出。施用无机复混肥对桉树的生长有明显的促进作用。在土壤肥力中等偏低的丘冈红壤上,追肥在桉树生长期前期施用效果最好,施肥量以0.3kg/株为最佳。 相似文献
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本文基于32块样地土壤数据,对亚热带日本落叶松中、幼龄林的土壤有机碳密度及其分配特征进行了分析,结果发现:(1)中龄林的有机碳含量、有机碳密度明显高于幼龄林;(2)混交林的有机碳含量、有机碳密度明显高于纯林;(3)0~80 cm的土壤有机碳密度为172.25 t/hm2。有机碳主要集中在表土层0~20 cm处,此表土层有机碳密度分别是土层20~40 cm、40~80 cm的175.21%、129.52%。在土层相同的情况下,随着土壤深度的增加,其土壤有机碳密度呈下降趋势;(4)与适宜亚热带地区生长的造林树种——杉木相比,日本落叶松林的土壤有机碳含量、土壤有机碳密度均明显高于20年生杉木人工林,说明日本落叶松林土壤的固碳能力大于杉木人工林,从侧面也反映了同样作为亚热带地区的造林树种,日本落叶松林要优于杉木人工林。 相似文献
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Investigation was conducted to analyze the effect of management measures such as trunk cutting and fertilization on frost resistant capability of young paulownia (Paulownia sp. ) plantation which had been undergone heavy frost damage in early 2008 in southern China. Experimental sites were located in the Paulownia fortunei forest consisting of 2-poplar clonal plantations in Chaling County. Paulownia fortunei, treated by root planting, trunk cutting and fertilization was called 2B; the contrast was called 1B. The results showed that the tree height, DBH, height under branch and lateral branch diameter in 2B were, respectively, 19.19%, 11.36%, 180% and 13.8% higher than those in 1B. The number of lateral branches in 1B was 2.8 times that in 2B. The icicle pressure beared by 2B was only 60.21% of that in 1B. There was nearly no potential damage in the 9treatment plot with 98% of the plants in the freeze injury grade I. In contrast, 50% and 36% of the plants in the control plot were observed, respectively, in freeze injury grades II and Ⅲ. Based on the present investigation, it can to be concluded that the applied management measures are effective in enhancing the resistant capability of young poplar plantations to frost damage. 相似文献
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坡耕地不同植被恢复对土壤理化性质的影响 总被引:1,自引:0,他引:1
通过对女儿寨小流域5种不同植被类型坡面的土壤物理、化学性质的测定,结果表明:①随着退耕还林后植物群落的演替,土壤容重呈变小之势,而总孔隙度、非毛管孔隙度、通气度则呈变大之势,土壤物理性质得到不断改善。②在5个类型中以自然恢复植被全量养分含量最高,枫香 扁柏最低;速效养分以柑桔为最高,其它几种类型没有规律性的差异。随着退耕还林后时间的延续,土壤有机质、全氮、全磷、水解氮的含量不断增加,土壤保肥、供肥能力随着群落演替而加强,土壤自肥能力也越强。 相似文献