滨海盐碱土改良新工艺条件下杨树林土壤特性的研究

Soil Physicochemical Properties of Poplar Plantation Stand Under the New Technique of Saline-alkali Soil Reclamation in Coastal Area

研究了滨海盐碱土改良新工艺条件下杨树林土壤的理化特性。结果表明,在养护管理措施相同的条件下,杨树林新工区土壤平均含水率为20.36%,显著高于对照区域杨树林的16.21%;新工区土壤容重均值为1.36g·cm-3,显著低于对照区域的1.46g·cm-3。新工区土壤pH为7.86,比对照区域土壤pH值低0.23,而全盐含量为1.96g·kg-1,显著低于对照区域的2.67g·kg-1。聚类分析结果表明,新工区土壤中的盐分以NaCl和Na2SO4为主,而对照区域杨树林土壤盐分以NaCl为主;新工区土壤有机质含量为17.53g·kg-1、速效氮含量为20.48mg·kg-1、速效磷含量为63.59mg·kg-1,分别是对照区的1.42倍、4.31倍和1.32倍。上述试验结果表明,滨海盐渍土改良新工艺条件在保持杨树林土壤水分、养分和疏松程度以及防止土壤返盐碱方面,全面优于对照区域,相应的表现为杨树成活率高,年生长量较大,长势良好。研究结果可为滨海重盐碱地区深根性树种的大面积栽植提供理论依据。

Soil physicochemical properties of poplar plantation stand under the new technique of saline-alkali soil reclamation in coastal area were investigated. The results show that the average soil moisture content of the new technique-used area was 20.36% which was significantly higher than that in the control（16.21%） under the same amount of water supply. Soil bulk density of the new technique-used area averaged 1.36 g·cm^-3, significantly lower than the control（1.46 g·cm^-3）. The mean soil pH in the new technique-used area was 7.86, lower by 0.23 than the control. Total salt content was 1.96 g·kg^-1 in the new technique-used area, significantly lower than the control（2.67 g·kg^-1）. The cluster analysis showed that NaCl and Na2SO4 were the main soil salinity in the new technique-used area, while NaCl was the main soil salinity in the control. The mean concentrations of soil organic matter, available nitrogen and available phosphorus content in the new technique-used area were 17.53 g·kg^-1, 20.48 mg·kg^-1 and 63.59 mg·kg^-1 respectively, which were 1.42, 4.31 and 1.32 times as high as the control. In a word, compared with the traditional technique, the new technique of saline-alkali soil reclamation was more efficient on the aspects of maintaining soil moisture and nutrients, keeping soil loosening and preventing the soil salinization. Thus higher survival rate and annual growth of poplar plants was found in the new technique-used area. This study could provide a theoretical basis and reference for planting deep-rooted trees in the coastal heavy saline areas.