Geostatistical Analysis On The Spatial Pattern Of The Constructive Species In Pine-Oak Forest, In Lingkong Mountains, Shanxi

In order to reveal the distribution pattern and spatial correlation of Pinus tabulaeformis population and Quercus wutaishanica population, author made an investigation on the distribution of the populations which grows in three different site conditions, the mountain ridge, gentle slope and valley areas, in the National Nature Reserve of Lingkong Mountain in Shanxi Province. Based on the data of the investigation the degree of spatial heterogeneity, composition and distribution pattern as well as scale, intensity and texture of spatial distribution pattern of the both populations in the three habitats were analyzed by using of geostatistical methods. The research results showed as follows.(1) The semivariograms fitted the exponential model well for P. tabulaeformis population at sites of the mountain ridge, but the spherical model did well for the population at both the gentle slope and valley areas. All three populations showed an aggregated pattern. The reason of spatial heterogeneity of the populations at the three sites was mostly due to the spatial autocorrelation, with a range of 11.16 m,9.99 m and 4.74 m for the mountain ridge, gentle slope and valley areas, respectively. The populations at the ridges and gentle slopes showed greater sill values and determinant coefficient but lower fractal dimension than that in valleys, indicating that the former two habitats are characterized by higher degree of spatial heterogeneity and more significant spatial patterns, but that didn’t in the valley populations.(2) The semivariograms of Q. wutaishanica at both the mountain ridge and gentle slopes fitted well for the spherical model, and the valley fitted well for the exponential model, suggesting the aggregated type of the spatial distribution pattern in all three habitats. In addition, the spatial heterogeneity of the populations in three habitats was mostly due to the spatial autocorrelation with a range of spatial autocorrelation of 4.96 m,3.66 m, 19.67 m, respectively. The Q. wutaishanica populations at the ridges and valleys showed greater sill values and determinant coefficient but lower fractal dimension than those in the Q. wutaishanica population in gentle slopes, indicating that the ridges and valleys are characterized by higher degree of spatial heterogeneity and more significant spatial patterns, but didn’t in the gentle slopes populations.(3) The P. tabulaeformis and Q. wutaishanica population are excellent accompanying species. The quantitative features, diameter structure, spatial distribution and spatial pattern between the two populations at different habitats have certain mutual supplement. There may be mutually beneficial relations and collaborative relationships between them, except the competition for resource. The ecological niche of the two populations showed a certain degree of overlap at the three habitats.From the analyses of the above, we could draw a conclusion that the variations in the seale, intensity, grain of spatial distribution patterns of P. tabulaeformis and Q. wutaishanica populations is likely resulted from both their intrinsic biological characteristics and the environmental factors.