江苏大丰麋鹿保护区不同改良措施对滩涂土壤的改良效应研究

Effects of Different Amelioration Measures on Coastal Saline Soil in The David's Deer Reserve of Dafeng County of Jiangsu Province

在大丰市麋鹿保护区内，设置滩涂荒地（A样区）、挖沟排盐结合耐盐植物初步改良（B样区）、挖深沟作垄结合耐盐植物多年改良（C样区）和在C样区改良基础上进行覆被种植再改良熟化（D样区）共4个试验样区，按0～20cm和20～40cm两层采集土壤，测定土壤pH和总盐分含量，分析、评价不同改良措施对苏北淤泥质滩涂土壤的改良熟化效应。结果表明，4样区相同层次土壤的总盐分含量差异显著，同一样区不同层次间的土壤总盐分含量也存在明显差异。其中A样区（对照样区）上、下层土壤的pH分别高达9．03和9．14，上、下层圭壤的盐分含量分别高达26．5g／kg和143g／kg，土表仅见零星碱蓬生长。C、B两试区的土壤pH与A样区几无差异，但土壤含盐量均较A样区大幅下降。样地D的土壤pH己降至816～8．35，土壤含盐量亦己降至2．9～2．2g/kg，仅相当于C样区的1／2左右，按照我国滨海盐土分级标准已属轻度盐化土。D试区内已能生长水稻、棉花、玉米等多种农作物。本改良模式实施简便、成本低、改良效果好，值得推广。

Four different trail plots, i.e., coastal wilderness （plot A）, temporary ameliorated plot by digging channel combined with planting salt-tolerance plants （plot B）, perennial ameliorated plot by digging deep channel combined with planting salt-tolerance plants （plot C） and a plot keeping on further improvements on the basal mode of plot C （plot D）, were selected from Dafeng County David＇s Deer Reserve in the north of Jiangsu province. Soils at 0 - 20 cm and 20 - 40 cm layers were collected, the total contents of water soluble salts and pH values were determined to estimate the effects of different amelioration measures on salty coastal saline soil. The results showed that the differences of the total contents of soil water soluble salts from the different plots were significant both in the same and in the different layers. The pH values of topsoil and subsoil in plot A （CK） were respectively 9.03 and 9.14 and the total salt contents were respectively 25.6 g/kg and 14.3 g/kg, only Suaeda Salsa could sporadically grow on topsoil in it. The differences of soil pH values were not significant between plot C, B and A, but the soil salt contents in plot C and B were much lower than plot A. The soil pH values in plot D declined respectively to 8.16 - 8.35 and the salt contents declined to 2.9 - 2.2 g/kg which was only about half of plot C. According to the grade standards of coastal saline soil, plot D could be defined as the slightly saline soil, and crops such as rice, corn and cotton could be planted in it. This amelioration model is effective in improving physical and chemical properties of coastal saline soil, and it is low-cost and easy to operate, thus worthy to be extended.