| The soil on the cut slope is the foundation of the vegetation's formation, growingand succession. Vegetation is indispensability to the protection and landscapes restoration ofslopes, while soil is the basic element of vegetation growing, developing and succession inslopes, so the soil underlay the restoration of the slope. We study the spatial variation of soilmoisture and soil nutrition as: soil moisture, total nitrogen (TN), available nitrogen (AN), totalphosphorus (TP), available phosphorus (AP), total potassium (TK), available potassium (AK),organic matter (OM).1. The spatial variations of soil moisture in slopes with different degrees, lengths (10 m, 20m and 30 m) and sections (up, middle and lower) were investigated. Results showed that: the soilwater moisture has the tendency of increasing at first, and then decreasing with the increasing ofslope steepness. The sequence of the magnitude of the heterogeneity is the bottom-slope＞themid-slope＞the top-slope along the same slope. Soil water moisture decreases with theincreasing of the slope-length: the shortest (10m) is 23.7％, and the longest (40m) is 21.78％, thesoil water moisture of the shortest slope is as 1.0684 times as that of the longest slope.2. The nitrogen contents (TN and AN) in soils of side slopes with different lengths (10 m,20 m, 30m) and at different positions (upside, middle, lower) were compared. Also thedifference of nitrogen contents (TN and AN) at three slope positions between roadside slope andnatural slope were compared. At the three slopes with different lengths, the range of total Ncontents is 10.5-7.4g/kg, and TN showed a decreasing trend with the increasing of length. ANshowed a consistently decreasing trend with the increasing of slope length. According to slopesection, in roadside slope the contents of total N fluctuate in the following order: upside＞middle＞lower, while the highest content of AN occurred at lower section. In contrast, in different positions of natural slope, the order of the contents of both the total N and the N is: up＜middle＜lower.3. In roadside slopes with different lengths, the loss of soil TP and AP contents have strongpositive correlation with slope length. As regard different slope section, soil TP and AP contentsexhibit a trend of moderation increase along the gradient up - middle - lower. The values TP andAP contents in soil collected at lower sections of slopes displayed highly scattering. To naturalslope, the AP content and utilization rate at different slope sections showed a coincident trend toroadside slope.4. In roadside slope soil, the influence of slope length to TK content was not significant. Atall three side slopes, the soil TK contents were about 4.3 g·kg-1, while the soil AK contentsdecreased with the increasing of slope length. At different slope sections of roadside slope, boththe TK and the AK content showed increasing trend along the gradient of up-middle-lower,moreover, the values of AK content at lower section scattered highly. However, at natural slope,no significant difference of potassium content has been found among slope sections. The TKcontent displayed no significant difference between roadside slope and natural slope, but at thelower section of roadside slope, the soil AK content was significant higher than that in naturalslope.5. The organic matter content of soil increased with the increasing of the slope length. Butthe influence of slope section on OM content in roadside slope was adverse to that in naturalslope. In roadside slope, the soil OM contents followed the order up＜middle＜slower, while innatural slope, the order is up＞middle＞slower.
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