土地利用方式如何影响土壤理化性质及其作用深度一直是土壤生态学的研究热点,但是对松嫩平原退化盐碱地的相关研究匮乏。以肇东实验林场为研究对象,对8种植被类型的3个土层0~60 cm进行采样,共测定13个相关指标,结果显示:不同植被对根系密度、土壤p H、速效磷含量、土壤含水量、电导率、有机碳含量、全氮含量具有显著影响:其中前3个在不同土层的种间差异显著不同,而其余4个指标在60 cm土壤内种间差异一致。具体表现为:0~40 cm水曲柳根系密度最大,但在40~60 cm草地根系密度最大;黄檗的p H值在0~20 cm最大,但是在40~60cm最小,而草地的p H值在20~60 cm均大于其他植物种类;速效磷含量在0~20、40~60 cm均是樟子松最小,但在20~40 cm层樟子松速效磷含量最高。草地土壤含水量26.7%,显著高于其它,是落叶松的1.8倍,其土壤电导率为503.4μs·cm-1,明显大于其它各植被类型;杨树、樟子松的土壤有机碳含量显著低于黄檗、榆树、草地和水曲柳;土壤全氮含量最低的樟子松和杨树仅为草地的72.3%。所有其他养分包括全磷、全钾、速效钾不同植被间没有差异。上述结果说明,与原有植被草地相比,松嫩平原盐碱化土壤造林虽然能降低盐碱化,但同时对水分消耗较大,造林各个树种对土壤养分消耗相差不大,多体现在有机碳和氮。这些发现可为今后该地区种间差异比较、土壤肥力评价、土壤养分收支平衡等研究提供指导。
The effects of different land use on soil properties and its functioning depth are prevailing hotspots in soil ecology, but few researches are available in degradation saline-alkaline soil, in Songnen Plain, northeastern China. Taking the Zhaodong Experimental Forest Farm as the research site, we sampled 3 soil layers from 8 vegetation types and measured 13 soil parameters. The results showed: root density, pH, available-P, soil moisture, EC, SOC and total N were significantly influenced by different vegetation types. Interspecies differences of first three parameters varied at different soil layers, while the other four parameters showed similar interspecies differences among whole soil profile. Root density in Fraxinus mandshurica plantation was the top in 0-40 em of the soil, but root density in grassland was the top in 40 -60 cm of the soil. Soil pH in Phellodendron amurense was higher than any other plant types in 0 - 20 cm of the soil, but it was lower than the others in 40 - 60 cm of the soil. Soil pH in grassland was higher than the others from 20 - 60 cm of the soil. Available-P in Pinus sylvestris was higher than any others respectively in the first and third soil layer, however it was lower than any other plant species in the second soil layer. Peak soil moisture was in grassland, that was 1.8 times higher than that in Larix gmelinii plantation ; EC in grassland (503.4 higher than that in all the other vegetation types. SOC in plantations of Populus, μs · cm-l) was significantly P. sylvestris were significantly lower than those in plantations of P. amurense, Ulmus pumila, F. mandshurica and grassland; Soil total N in Populus and P. sylvestris were only about 72.3 % of that in grassland ; There was no differences in total P, total K and available-K among different plants. Therefore, afforestation with proper species in Songnen Plain could reduce soil salinity-alkalinity with the expense of more water consumption and similar soil nutrients depletion reflected in SOC and total N, Our findings woul