石漠化最突出的特征是水土和养分的流失，石漠化发展造成地表严重缺土。稀缺的土壤资源是生态恢复的重要限制性因素，其中，土壤质量是生态恢复重建的关键。研究石漠化生态恢复过程中土壤质量的变化特征，对石漠化区的植被重建和土壤养分的调控与管理具有重要意义。以环江古周生态恢复重建区为研究区，在野外调查和资料查阅的基础上，在研究区内选取具有代表性的人工任豆（Zenia insignis）林，分别在坡地和洼地按照石漠化的不同程度设置样地。采用野外取样与室内分析相结合的方法，采集土壤样品。研究了潜在、轻度、中度和重度石漠化土地及其分层土壤的容重、含水量、pH 值、有机质（SOM）、全氮（TN）、全磷（TP）、全钾（TK）、碱解氮（AN）、有效磷（AP）和速效钾（AK）等土壤质量要素的变化情况并对其进行分析。结果表明，（1）石漠化生态恢复过程中，植被系统的恢复促使生物量增加，土壤有机质的来源变广，土壤养分含量增多。（2）石漠化生态恢复过程中，土壤质量不断变好，促进了地表植被的生长，石漠化治理效果明显。因此，土壤质量的向好与石漠化生态恢复过程形成相互促进的关系，并在生态恢复方向和阶段上具有一致性和同步性。（3）从重度石漠化到轻度石漠化，坡地土壤全氮平均含量从1.22 g·kg-1上升到1.88 g·kg-1，增幅为54.10%；洼地土壤全氮平均含量从1.13 g·kg-1上升到1.36 g·kg-1，增幅仅为20.35%。坡地样地土壤碱解氮平均含量从84.55 mg·kg-1上升到164.31 mg·kg-1，增幅为94.33%；洼地样地土壤碱解氮平均含量从41.90 mg·kg-1上升到82.57 mg·kg-1，增幅为97.06%。坡地样地土壤速效钾平均含量从36.61 mg·kg-1上升到58.52 mg·kg-1，增幅为59.85%；洼地样地土壤速效钾平均含量从15.02 mg·kg-1上升到28.09 mg·kg-1，增幅为87.02%。（4）研究区内石漠化生态恢复过程与土壤质量状况关系密切，随着石漠化治理状况的好转，土壤含水量、有机质、全氮、碱解氮、速效钾含量呈现出上升趋势，土壤容重、pH值减小，土壤肥力增加。%Serious soil erosion and drastic decrease in soil productivity caused by karst rocky desertification can endanger the functions of karst ecosystem. Thus, to better understand the changes of soil quality in the process of ecological restoration, which can provide scientific basis for soil nutrient regulation, is important for ecosystem management in vulnerable karst rocky desertification area. This study was conducted in the karst ecological restoration and rehabilitation region of Guzhou village, 21 typical sample plots of Zenia insignis along a rocky desertification gradient were selected based on field survey and literature search, among which 9 sample plots are on a slope and 12 sample plots are in a depression area. Soil samples were collected along a rocky desertification gradient(potential rocky desertification, slight rocky desertification, moderate rocky desertification, and severe rocky desertification), and the changes of soil quality in different layer, indicating by soil bulk density, soil water content, pH value, soil organic matter, soil total nitrogen, soil total phosphorus , soil total potassium , available nitrogen, available phosphorus, and available potassium, were studied using laboratory analysis method. Results showed that, (1) Vegetation recovery in rocky desertification area provided more organic matter to the soil and therefore resulted in the increase of soil nutrient contents. (2) During the process of ecological restoration, soil quality was getting better and vegetation was accordingly growing better, which indicated that the effect of rocky desertification control effect was obvious. This also indicated that there was a positive relationship between the improvement of soil quality and the restoration of karst ecosystem in rocky desertification area. (3) From severe rocky desertification to slight rocky desertification, the average of total nitrogen in the slope area increased from 1.22 g·kg-1 to 1.88 g·kg-1, by 54.10%;the average of total nitrogen in the depression area increased from 1.13 g·kg-1 to 1.36 g·kg-1, only for 20.35%. The average of available nitrogen in the slope area increased from 84.55 mg·kg-1 to 164.31 mg·kg-1, by 94.33%;the average of available nitrogen in the depression area increased from 41.90 mg·kg-1 to 82.57 mg·kg-1, by 97.06%. The average of available potassium in the slope area increased from 36.61 mg·kg-1 to 58.52 mg·kg-1, by 59.85%;the average of available potassium in the depression area increased from 15.02 mg·kg-1 to 28.09 mg·kg-1, by 87.02%. (4) There is a synchronous relationship between the changes of soil quality and the process of eco-restoration in karst rocky desertification area. With the improvement of the rocky desertification, soil water content, soil organic matter, soil organic carbon, total nitrogen, available nitrogen, and available potassium showed an increasing trend, while soil bulk density and pH value showed a decreasing trend, which indicated an increase in soil fertility.
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