基于耦合关联分析的护岸植被恢复土壤抗蚀性综合评价

Comprehensive Evaluation on Recovery of Soil Anti-erodibility by Revetment Vegetation Based on Coupling Relationship Analysis

为综合评估护岸植被对土壤抗蚀性的影响,选取草地、灌木、乔草和乔灌草模式土壤为研究对象,以自然坡面为对照,利用主成分分析法分析不同理化指标对土壤抗蚀性的影响,同时利用灰色关联度分析法分析土壤理化性质指标与土壤抗蚀性指标之间的关联程度,并在此基础之上构建土壤理化性质指标与抗蚀性指标的耦合模型,以综合评价不同护岸植被模式土壤的抗蚀性。结果表明:>0.25 mm水稳性团聚体、容重、有机质、碱解氮、有效磷、速效钾、平均重量直径和水稳性指数是影响研究区土壤抗蚀性的主要因子,其中>0.25 mm团聚体对区域土壤抗蚀性的影响程度最大;平均重量直径、水稳性指数与土壤理化性质指标呈中等关联性,其关联性排序为>0.25 mm团聚体>有机质〉碱解氮〉有效磷>速效钾〉容重;不同护岸植被模式土壤抗蚀性质与理化性质指标的系统耦合度整体属于弱协调,协调度的大小顺序为乔草〉乔灌草〉草地〉灌木〉自然坡面,乔草模式属于中度协调,其他模式均属于弱协调状态,说明乔草模式为护岸植被的最佳组合模式。土壤抗蚀性质与理化性质指标的协调程度可以为科学改善河岸土壤结构、提高土壤抗蚀性及为护岸植被的优选提供参考依据。

In order to comprehensively evaluate the effects of revetment vegetation on soil anti-erodibility, the soils under grasslands, shrubs, arbor-grasslands and arbor-shrub-grasslands were selected, the effects of different physiochemical indexes of soil anti-erodibility were analyzed by principal component method, and gray relevant analysis was used to study soil physiochemical indexes and their relation with soil anti-erodibility indexes. Furthermore, a coupling model was constructed to comprehensively evaluate the influence of different revetment vegetation patterns on soil anti-erodibility. The results showed that the main factors of soil anti-erodibility were >0.25 mm water stable aggregate, bulk density, organic matter, alkaline nitrogen, available phosphorus, available potassium, mean weight diameter and water stable index, and >0.25 mm water stable aggregate had the greatest impact on soil anti-erodibility. There was a moderate correlation between mean weight diameter, water stability index and soil physiochemical properties. The correlation from high to low was 0.25mm aggregates > organic matter > alkaline nitrogen > available phosphorus > available potassium > bulk density. The system coupling degree between soil anti-erodibility and physiochemical indexes in different revetment vegetation patterns was weakly coordinated, and the coordination from high to low were arbors-grasslands > arbor-shrub-grasslands > grasslands > shrubs > natural slope. The coordination of arbor-grasslands was moderate while and the others were weak. Furthermore, the result showed that arbor-grasslands were the best combination model of revetment vegetation. The coordination degree between soil anti-erodibility and soil physiochemical indexes could provide scientific references for the improvement of soil structure and anti-erodibility as well as for the preferential selection of revetment vegetation.