苏北滨海盐渍土土壤基本性质及其对中山杉生长的影响

Basic properties of coastal saline soil in northern Jiangsu and their effects on the growth of Taxodium‘Zhongshanshan’

通过对江苏省盐城市大丰区不同中山杉(Taxodium)造林地的土壤盐分含量、有机质含量等土壤性质指标及中山杉成活率、胸径和树高等生长指标调查,分析了不同指标之间的相互关系,明确了土壤含盐量对中山杉生长的影响。结果表明,12块造林样地0~50.0 cm深度范围的土壤含盐量为0.04%~0.80%,不同造林地之间的土壤含盐量差异较大;土壤有机质含量为4.37~11.52 g/kg,普遍偏低;土壤全氮含量与含盐量呈显著负相关,与有机质含量呈极显著正相关;中山杉的成活率、胸径以及树高与土壤含盐量之间均呈负相关关系,可用一元二次方程拟合土壤含盐量对中山杉生长指标的定量关系;当土壤盐分含量高于0.60%时,中山杉的成活率低于50%,胸径和树高明显偏低,当土壤盐分含量低于0.30%时,中山杉的成活率在80%以上,胸径和树高也比较正常。

Based on the investigation of soil salt content,organic matter content,tree survival rate,diameter at breast height(DBH)and tree height of Taxodium‘Zhongshanshan'in different afforestation sites in Dafeng District,Yancheng City,Jiangsu province,the relationship between soil properties and tree growth indices was analyzed.The influence of soil salt content on the growth of Taxodium‘Zhongshanshan'was clarified.The results showed that the soil salt content in the depth range of 0-50.0 cm in 12 afforestation sites was between 0.04%and 0.80%,and the difference in soil salt content among forestation sites was great.The content of soil organic matter was 4.37-11.52 g/kg,which was generally low.The soil total nitrogen content was significantly negatively correlated with the salt content and significantly positively correlated with the organic matter content.There was a negative correlation between the survival rate,DBH,tree height and soil salt content,and the quadratic polynomial equation could be used to describe the quantitative relationship between soil salt content and the growth indices of Taxodium‘Zhongshanshan'.When the soil salt content was higher than 0.60%,the survival rate was less than 50%,and the DBH and tree height were significantly lower.When the soil salt content was lower than 0.30%,the survival rate of Taxodium‘Zhongshanshan'was more than 80%,and the DBH and tree height were also nearly to normal level.