Study On The Structure And Heterogeneity Of The Urban Green Space In Fuzhou

The structure and heterogeneity of urban green space in the five districts in Fuzhou , which included the main tree species with diameter at breast height(DBH) distribution, height class, health class, importance value, relation and the green space patches with areas distribution, perimeter distribution, porosity, connectivity, marginal density, dominance, the characteristics of geo-statistics and so on, were studied in quantification by the use of the principle of landscape ecology combining with the method of studying porosity and connectivity and geo-statistics. The following results were achieved:1) The 2005 greenbelt status quo map in Fuzhou was got by the combining use of processing remote sensing image and field investigation. Then the map was changed into the type of vector. The patch area, perimeter and quantity were calculated by the inner function of AUTOCAD.2) Based on the method of statistics, the structure of urban green space in Fuzhou were studied according to the indexes of quantity, height, DBH, canopy of tree species in the major quadrats. The main trees were some minority species in the angle of number. The relation between the species, individuals and height, DBH was that the latter increased along with the former while the height was less than 8 m and DBH was less than 30 cm in major trend however declined fast while the critical points was passed. The even limbs of trees were small comparatively. This showed that: the structure of urban green space had not been the best so far, and the ecology benefit would be more evident in the process of time.3) The trees' health situation of urban green space in Fuzhou was studied according to the model of growing index, and the comprehensive manifestations were used to analyze the relation among trees. And the Correlation constellation of main trees was protracted combining with the formula of Jaccard quantitative coefficient of correction. At last, the reference keynote and skeleton tree species was confirmed, and 7 tree combinations fitting the practice manifestations were presented.4) The tree specie characteristic of urban green space was described in quantification by the use of the indexes such as: leaf area, leaf area index, specie diversity, specie importance value and dominance. And the greenbelts were studied in quantification by the use of the greenbelt perimeter, area, density index, edge index, fractal dimension, diversity, dominance, evenness. The results indicated that the greenbelts were in the type of chess, however, it could not meet the requirement of the development dimensions neither in total areas nor in quantity.5) Based on the porosity and background principle of landscape ecology, the porosity of greenbelts were studied. Porosity and background were in reverse in area. The greenbelt was in the type of hole as cities were in the background of pavement surface. The stronger the porosity was, the bigger the ecology benefit was. The porosity index was calculated by the moderate method (13 different scales was taken). The results reflected that the distribution of greenbelt in Fuzhou was strongly random. So the distribution pattern should be controlled...