岩石边坡生境形态结构特征对植被自然恢复能力的指示性

Habitat Morphostructural Characteristics as Indicator of Natural Vegetation Restorability of Rocky Highway Slopes

构建植被恢复指数(I VR),对鲁中山区公路花岗岩边坡的植被自然恢复成效进行样方评价,识别影响植被自然恢复能力的关键生境因子,并建立基于岩缝与岩台面积指数和恢复年限的植被恢复成效预测模型。结果表明,不同生境条件下公路岩石边坡植被的自然恢复效果差异较大,样方I VR的最高值和最低值分别为1.89和0.29,恢复较差样方(A)组平均盖度为35.7%,平均地上生物量为147.7 g·m-2,分别不及恢复较好样方(C)组1/2和1/3;岩缝与岩台面积、恢复年限、岩台面积、平均土层厚度、岩缝面积、坡位和岩台土层厚度这7个生境因子与I VR密切相关,其参数值在A组和C组间差异显著(P<0.05),表明岩石边坡植被自然恢复成效和恢复能力与生境形态结构特征有很大关联性,而岩缝与岩台发育程度和数量多寡对其影响最大。岩缝与岩台面积指数是指示边坡裸岩植被自然恢复能力和预测植被自然恢复成效的重要参数。

Natural revegetation on granite highway slopes in the mountainous area of Central Shandong Province was evaluated at quadrat level using a vegetation restoration index （IVR） just established.Key habitat factors affecting natural vegetation restorability were identified and a model was built up for predicting natural revegetation based on the area index of rock crevice and rock platform （IAcp） and years of restoration.Results show that habitats different in condition differed rather sharply in natural revegetation on rocky highway slopes,with the highest and lowest quadrat IVR being 1.89 and 0.29,respectively,and the average vegetation coverage （35.7％） and average aboveground biomass （147.7 g · m-2） of the quadrat group （Group A） which is poor in revegetation being no more than one half and one third,respectively,that of the quadrat group （Group C） which is good in revegetation; Of the seven habitat factors closely related to IVR,five are morphological factors characterizing development degree of the rock crevice and rock platform and thickness of the soil layer,also their parameters between Group A and Group C varied significantly （P＜0.05）,which demonstrates that natural vegetation restoration and restoration ability are well related to habitat morphostructural characteristics of the rocky highway slopes,and significantly affected by the development level and amount of rock crevice and rock platform; and IAcp is a critical parameter indicating natural vegetation restorability and one to predict natural revegetation.