无人机近景摄影技术在崖壁植物多样性研究中的应用

崖壁植物具有不可及或不易及的特点，有关崖壁植物的调查一直面临着高成本、高风险和难鉴定的难题。本研究创新性地提出一种采用无人机近景摄影技术对崖壁植物拍照及专家鉴定的调查方法，通过分析崖壁植物群落的Margalef、Simpson与Pielou这3种多样性指数的变化，探究海拔、光照、立地条件与水汽条件这4种因子对崖壁植物多样性的影响。研究结果表明：本次调查共发现崖壁植物267种，分属于58科、140属；崖壁植物物种数目与海拔高度变化服从正态分布，物种数量在中海拔700-800m达到峰值，Simpson指数与Pielou指数在低海拔时达到最高，随海拔的升高而下降，但不表现出明显的变化规律；崖壁植物在不同的立地条件下，植物群落的物种组成、优势种类与出现频率均有所不同；崖壁植物的相关性分析显示，在光照条件出现差异或立地条件不同时，崖壁植物各指数之间存在着不同的显著性关系；近水崖壁植物与对照组的分析结果对比显示，崖壁植物的数量与物种组成受崖壁间水汽条件的影响，崖壁水汽条件越高的地区有着更丰富的植物种类。本研究表明崖壁植物的分布特征是受海拔、光照、立地条件以及水汽条件等多因素的综合作用而成。

Application of UAV close-range photography in the study of plant diversity on cliff walls

The surveys about cliff plants have been faced with the problems of high costs, high risks and difficult identification because they are inaccessible. In this study, an innovative survey method, UVA close-range photography, is proposed for the identification of cliff plants. By studying the relationship of the Margalef index, Simpson index and Pielou index of cliff plants, the effects of altitude, light, site conditions and water vapor conditions on cliff plants are explored. In total 267 species of cliff plants which belong to 58 families and 140 genera are found in this survey. The results show that the relationship between the species of cliff plants and the change of altitude follows a normal distribution, reaching the peak at the middle altitude 700-800m. The Simpson index and Pielou index reach the peak at low altitude, which decrease with the increase of altitude, but do not show an obvious change rule; under different site conditions, the species composition, dominant species and occurrence frequency of plant communities are different; the correlation analysis of cliff plants shows that there are different significant relationships among the indexes of cliff plants when the light conditions are different or the site conditions are different. The difference between the cliff plants close to the water area and the control group shows that the species composition and quantity of cliff plants are affected by the water vapor conditions among the cliff walls, and the higher the water vapor condition is, the more abundant plant species are in the area. The characteristics of the distribution of cliff plants are the result of the combination of altitude, light, site conditions and water vapor conditions.