质量指数法表征不同处理模式对滨海盐碱地土壤质量的影响

CHARACTERIZATION OF EFFECTS OF MANAGEMENT MODES ON QUALITY OF COASTAL SALT-AFFECTED SOILS WITH QUALITY INDEX

以自然演化模式、林业治理模式和农业治理模式的土壤为研究对象,运用土壤单质量指数(Soil single quality index,SSQI)和土壤综合质量指数(Soil comprehensive quality index,SCQI)法,研究了滨海盐碱地土壤质量的动态变化规律。结果显示:根据土壤单质量指数,研究区土壤容重、总孔隙度、通气度和含盐量总体属于优、良级水平,pH、全磷、有效磷和速效钾属于中级水平;而质地、有机质、全氮和微生物生物量属于中、差级水平。农业和林业治理模式能有效地优化滨海盐碱地土壤的含盐量、有机质、全氮、全磷、有效磷和速效钾指数。根据土壤综合质量指数,研究区土壤综合质量指数平均为1.2±0.1(中级水平),土壤质量一般,不利于植物生长。其中农业治理模式的土壤综合质量指数为1.24±0.11,林业治理模式为1.2±0.1,自然演化模式为1.14±0.09。土壤综合质量指数显示不同处理模式的土壤质量有一定的差异,这一差异的稳定性较高,但未达统计分析的显著性水平。人为干扰如农业和林业治理模式是滨海盐碱地土壤质量在短期内产生时空变异的主要诱因,加速了滨海盐碱地土壤质量的演化进程。

Natural evolution-based management mode, forestry-based management mode and agriculture-based management mode are three classical modes of management applied extensively to reclamation of coastal salt-affected land. To reveal effects of the three typical modes of management on soil quality, soil samples were taken from fields under the three modes of management, separately for analysis of laws of the dynamic variation of soil quality of the lands, using the soil single quality index （SSQI） method and the soil comprehensive quality index （SCQI） method. Results show that based on SSQI, the soil in the study zone on the whole could be sorted into the categories of excellent and good in soil bulk density, total porosity, aeration porosity, and salt content, into the category of moderate in soil pH, total phosphorus, available phosphorus, and available potassium, and into the categories of moderate and poor in soil texture, organic matter, total nitrogen, and micro biomass, indicating that the agriculture- and forestry-based managements could effectively improve the soil indices, such as salt content, organic matter, TN, TP, available P and available K. But based on SCQI, the mean value was 1.2 ± 0.1, implying that the soil was ordinary in quality and unfavorable for plant growth. The mean SCQI value of the agriculture-based management, forestry-based management and natural evolution-based management was 1.24 ± 0. 11, 1.2 ±0. 1 and 1. 14 ± 0.09, respectively, which indicates that differences exist between the three modes in soil quality. Though the differences were rather stable, they did not reach up to the significant level statistically. Artificial interferences, such as forestry- and agriculture-based managements, are the main factor inducing temporal and spatial variation of the soil quality within a short period of time, thus accelerating the evolution process of the coastal salt-affected land in soil quality.