酸雨中的SO2-4和NO-3等阴离子在土壤中迁移时会引起大量的盐基离子淋溶，导致土壤退化。用室内土柱模拟SO2-4和NO-3在红壤旱地各土层中的垂直穿透状况，并用Hydrus-1D模型对试验结果进行了拟合和预测。结果表明，NO-3在红壤各层中的穿透速度较快，其中在耕作层的穿透曲线峰值最高，C/C0达到0.39，峰值高低顺序依次为：耕作层>母质层>淋溶层>犁底层。SO2-4在土柱中的穿透速度远低于NO-3，穿透曲线有明显的拖尾现象。其在各土层的穿透时间依次为：母质层>犁底层>淋溶层>耕作层；而其峰值高低顺序依次为：耕作层>淋溶层>母质层>犁底层，最高点耕作层的顶点C/C0 仅为0.22。用Hydrus-1D模型对试验结果进行模拟，所得的SO2-4和NO-3穿透土壤的浓度模拟值与其实测值均呈极显著的正相关关系。利用数学模拟获得了饱和导水率和垂直扩散率等溶质运移参数，并预测了研究区酸雨后SO2-4和NO-3在红壤耕层的迁移状况，表明SO2-4会在酸雨结束后持续淋溶，从而影响土壤中Ca、Mg等盐基离子的淋失。

The influence of texture, bulk density, and organic matter content on the process of nitrate vertical transport in the three main paddy soils (Bai soil, Huangni soil and Wushan soil) of the Tai Lake region were studied in the soil columns. Breakthrough curves (BTC) were obtained separately for each of thirteen horizons. The results were as follows: vertical transport velocity of nitrate decreased, and the BTCs of nitrate were more dispersed, in each horizon from the surface layer to the bottom in every soil profile. Among the three soils, the average flux ofWushan soil was the least and its nitrate BTC was the most dispersed. Under saturated conditions, nitrate penetrated the soil column quickly. The transport of nitrate was affected by clay content. As the clay content increased, nitrate outflow was retarded, and the peak concentration was reduced. Nitrate BTCs rose and fell gently when the nitrate concentration was lower. All nitrate BTCs were asymmetric, and tailing was more obvious when clay content was high. Soil bulk density and the organic matter content also affected the vertical transport of nitrate. Low bulk density and high organic matter content were each associated with faster nitrate transport. An analytical solute transport model (CXTFIT 2.0) was used to estimate the nitrate dispersion coefficient and average pore-water velocity from the observed breakthrough curves. The results showed that the analytical solute transport model was suitable in fitting the observed nitrate transport in these soils. The dispersion coefficient was found to be a function of average pore-water velocity.

The characteristics of nitrate horizontal transport in a major paddy soil, Wu Shan soil in the Tai Lake region, were studied. The concentration of nitrate during horizontal movement decreased with the increasing in distance from the tracer source, the change following a logarithmic function. The concentration of the nitrate was strongly correlated with the soil moisture content, as an exponential function. The horizontal transport velocity of nitrate was significantly correlated with the distance of the tracer source as power function. Therefore, the velocity of nitrate horizontal transport was controlled by the concentration gradient of nitrate, and soil water potential gradient from beginning to the 20 cm mark in the horizontal column. However, the velocity of nitrate horizontal was stable beyond 20 cm, where it was controlled by soil matric potential.

在分析江西兴国县激水河流域东村水文站1967～2005年逐日降雨资料的基础上，利用国内外常用的6种降雨侵蚀力计算模型，即周伏建等. (A)、章文波等(B)、吴素业（C）、史志华等（D）、Wischmeier等（E）和CREAMS（F）模型，分别计算其降雨侵蚀力大小。用有效系数和相对偏差对模型的计算结果进行了分析。结果表明：模型C比较理想，在计算其降雨侵蚀力时具有较高的有效系数（0.97）和较低的相对偏差（0.073）。月雨量模型（A、C、E）与日雨量模型（B、D、F）相比，具有较高的有效系数和较低的相对偏差，说明月雨量模型要优于日雨量模型。从趋势系数来看，这两类模型的趋势系数均值分别为0.058和0.196，均为正值，说明39年来潋水河流域年降雨侵蚀力的年际变化呈增加趋势；后者高于前者，说明用日雨量模型计算的年R值，其增加趋势高于月雨量模型。

在温室盆栽条件下，通过单独或联合添加生物表面活性剂鼠李糖脂（RH）和接种多环芳烃专性降解菌（DB），研究了利用生物表面活性剂-微生物强化紫花苜蓿（Medicago sativa L.）修复多环芳烃（PAHs）长期污染土壤的效果。结果表明，添加鼠李糖脂和接种PAHs专性降解菌能促进紫花苜蓿的生长和土壤中PAHs的降解。培养90d后，RH、DB处理的PAHs的降解率分别为30.0%和49.6%，均高于对照处理（CK）（21.7%）。RH+DB处理PAHs的降解率最高达53.9%，说明鼠李糖脂和PAHs专性降解菌协同作用显著。另外，随着PAHs苯环数的增加，其平均降解率逐渐降低，但是接种PAHs专性降解菌能够提高4环和5环PAHs的降解率。同时也发现土壤中脱氢酶活性和PAHs降解菌数量越高的处理，土壤PAHs的降解率也越高。所以添加鼠李糖脂和接种PAHs专性降解菌能够有效促进土壤多环芳烃降解。