安徽省一级古树的资源特征及影响因子分析

Analyses on resource characteristics and impact factors of first-class old trees in Anhui Province

在文献查阅和实地调查部分地区的基础上,对安徽省现存一级古树的物种组成和地理分布格局进行了分析,并对一级古树的树龄、树高、胸围和冠幅与环境因子的相关性进行了研究。结果表明:安徽省一级古树有616株,隶属于30科52属62种(变种);银杏科(Ginkgoaceae)、红豆杉科(Taxaceae)、柏科(Cupressaceae)、壳斗科(Fagaceae)、樟科(Lauraceae)和榆科(Ulmaceae)为优势科,重要值分别为36.11%、12.98%、9.89%、8.11%、7.33%和6.07%;银杏(Ginkgo biloba Linn.)、圆柏(Juniperus chinensis Linn.)、香榧(Torreya grandis Fort. ex Lindl.)、樟树[Cinnamomum camphora(Linn.) J. Presl]、南方红豆杉[Taxus wallichiana var.mairei(Lemée et H. Léveillé) L. K. Fu et Nan Li]和苦槠[Castanopsis sclerophylla(Lindl. et Pax.) Schott.]为优势种,重要值分别为36.11%、8.05%、7.98%、7.35%、5.03%和4.56%;科和属的分布区类型均以热带和温带分布型为主,尤其是泛热带和北温带分布型。安徽省一级古树的树龄结构整体呈金字塔形分布,主要集中在500-820 a;而树高、胸围和冠幅结构呈正态分布,分别主要集中在15.0-25.0 m、300.0-600.0 cm和5.0-15.0 m。不同城市一级古树的个体数、种数、Shannon-Wiener多样性指数、Simpson多样性指数、Margalef丰富度指数和Pielou均匀度指数存在较大差异,全省一级古树的个体数和种数总体呈南多北少的特点。相关性分析结果表明:安徽省一级古树的树龄、树高和胸围与多数环境因子呈显著或极显著相关性,但冠幅与各环境因子的相关性却不显著。综上所述,安徽省一级古树种类较丰富,但分布不均匀,植物区系类型与地理位置相吻合;环境因子对安徽省一级古树的影响较大,人类活动对其影响也较大,建议结合不同城市的实际情况制定有针对性的古树保护措施。

On the basis of literature investigation and field survey of some areas, species composition and geographical distribution pattern of existing first-class old trees in Anhui Province were analyzed, and the correlations of age, height, breast circumference, and crown width of first-class old trees with environmental factors were studied. The results show that there are 616 first-class old trees in Anhui Province belonging to 62 species(varieties) in 52 genera of 30 families;Ginkgoaceae, Taxaceae, Cupressaceae, Fagaceae, Lauraceae, and Ulmaceae are dominant families with importance values of 36.11%, 12.98%, 9.89%, 8.11%, 7.33%, and 6.07%, respectively;Ginkgo biloba Linn., Juniperus chinensis Linn., Torreya grandis Fort. ex Lindl., Cinnamomum camphora(Linn.) J. Presl, Taxus wallichiana var. mairei(Lemée et H. Léveillé) L. K. Fu et Nan Li, and Castanopsis sclerophylla(Lindl. et Pax.) Schott. are dominant species with importance values of 36.11%, 8.05%, 7.98%, 7.35%, 5.03%, and 4.56%, respectively;the areal types of family and genus are mainly Tropical and Temperate types, especially Pantropic and North Temperate types. The tree age structure of first-class old trees in Anhui Province shows pyramid distribution as a whole, and mainly distributes in the range of 500-820 a;while height, breast circumference, and crown width structures show normal distribution, and mainly distribute in the ranges of 15.0-25.0 m, 300.0-600.0 cm, and 5.0-15.0 m, respectively. There are relatively great differences in individual number, species number, Shannon-Wiener diversity index, Simpson diversity index, Margalef richness index, and Pielou evenness index of first-class old trees in different cities, on the whole, individual number and species number of first-class old trees in the whole province appear the characteristics of more in the south and less in the north. The correlation analysis result shows that there are significant or extremely significant correlations of age, height, and breast circumference of first-class old trees in Anhui Province with most environmental factors, but there is no significant correlation of crown width with each environmental factor. In conclusion, the species of first-class old trees in Anhui Province are relatively abundant, but their distribution is not even, and the flora type is consistent with geographical location. Environmental factors have great effects on first-class old trees in Anhui Province, human activity also has a great effect on them, thus, it is suggested to develop targeted protection measures of old trees based on the actual situations of different cities.