武夷山风景区森林景观土壤物理性质异质性及其分形特征

景观异质性是景观的重要属性,是形成不同景观结构和功能的基础(Formanet al.,1986)。它直接影响着景观的生物多样性和生产力,以及资源、物种在景观中的分配与传播。对景观整体功能及生态过程有重要的控制作用(Turneret al.,1987;1991),因此它是景观生态学的研究核心之一。景观异质性不仅与干扰(自然的和人为的)、生物群落定居和内源演替等方面有关,亦受景观内空间单元的自然地理特征和地质地貌过程的影响(Forman,1990;伍业钢等,1992)。土壤异质性是景观异质性的具体体现,也是造成景观异质性的重要原因之一。土壤异质性的研究有助于揭示景…

Soil Physical Property Heterogeneity and Its Fractal Features of Different Forest Landscapes in the Wuyishan Scenery District

The condition of soil structure is an important factor to affect soil fertility.The soil heterogeneity,which embodies the landscape heterogeneity,has an important role in revealing the form mechanism,function and variation of landscape.In this paper,the soil physical property heterogeneities of six types of forest landscape in Wuyishan scenery district include Pinus massoniana forest, Cunninghamia lanceolata forest,economic forest,bamboo forest,broad leaved forest and Camellia sinensis plantation were analyzed,and the fractal model was used to study the soil aggregate structure.The results showed that the soil physical property heterogeneities of different forest landscapes were distinct.The stand structure of three natural forests( Pinus massoniana forest, Cunninghamia lanceolata forest and broad leaved forest)were more complex than that of three artificial forests(economic forest,bamboo forest and Camellia sinensis plantation),thus,their fractal dimensions of soil aggregate were lower,the contents of the particle > 0.25 mm aggregate and > 5 mm aggregate were higher,the capacity of stable aggregate composition under water and permeability of soil were more splendid,the performance of self-regulation and resistance were better,and the non-capillary pore of soil were more flourishing than artificial forests. The regression models for fractal dimension (D)of aggregated structure and water stable aggregate(>0.25 mm and >5 mm)content,and for D and destroyed structure percentage were further established,and the results indicated the their regression relationships of all the models were remarkable,therefore,the fractal dimension of soil structure could be used as an index in characterizing the soil fertility.