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作 者 ：徐燕千 龙文彬

期 刊 ：林业科学 1983年 19卷 3期 页码：225-234

关键词：造林；

摘 要 ：本文在广泛调查分析的基础上,通过数理统计方法,确定在珠江三角洲范围内,影响林木生长的主要土壤因子是pH、全盐量和水位状况。用逐步回归方法选出了最优方程。落羽杉(Taxodium distichum)、池杉(Taxodium ascendens)、木麻黄(Casua-rina equisetifolia)和水松(Glyptostrobus pensilis)是珠江三角洲农田防护林的主要造林树种。土壤反应的最佳适生值,落羽杉和池杉为pH6.1,木麻黄和水松为pH7.0—8.0。这4种树种都有一定的抗盐能力,在全盐量高达0.38%的盐渍土上,仍生长正常。但落羽杉和池杉的生长速度与土壤全盐呈负相关。耐水湿树种落羽杉、池杉和水松分别在离水面50厘米和30厘米的种植点上表现最佳。珠江三角洲可划分为5个立地类型,即低丘淋溶型;平原淡水型;河网潮灌型;滨海反酸型;滨海砂土型。根据不同的立地类型,提出了适宜的农田防护林造林树种,为适地适树,提供依据。

Abstract:An extensive survey was made of the adaptive character and species choice of main planting trees of farmland shelterbelt in the Pearl River Delta.On the basis of investigation and analysis,the acidity of soil,the total content of salt and the height of water level were determined as the main site factor affecting the growth of forest by means of mathematical statisties.The optimum equation was selected by regression: y_D(over pH6.1)=8.0927-0.6473x₁-0.5059x₂ y_D(under pH6.1) = 3.7641-16.6671x₁-0.0027x₂ Taxodium distichum,Taxodium ascendens,Casuarina equisetifolia,and Glyptostrobus pensilis are the main planting tree species of farmland shelterbelts in the Pearl River Delta.pH6.1 is the optimum value of soil acidity suitable to Taxodium distichum and Taxodium ascendens,and pH 7.0—8.0 suitable to Casuarina equisetifolia and Glyptostrobus pensilis.All the 4 species of trees have certain salt-resistant capability,when they are planted on the salinized soil the total salt content of which is 0.38%,they still grow well; but growing speed of Taxodium distichum and Taxodium asoendens shows negative correlation to the total salt content of soil.Water-resistant and moisture-resistant species Taxodium distichum,Taxodium asoendens,and Glyptostrobus pensilis on the planting point,i.e.50cm and 30cm above the water level,show the best performance. 5 site types are classified in the Pearl River Delta,i.e.lower downland leaching type,the plain fresh water type,the network tide-irrigating type,the seashore acid overflówing type and the seashore sandy type.Various tree species suited for planting in the farmland shelterbelt are recommended according to different site types.

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