Study On Biological Firebreak Belt System Of Guangzhou

The forest fire prevention is the very important factor of the sustainable development of forestry;"the green fire protection" is the vast research. Taking Guangzhou as the research object, the paper collected the massive historicaldata of Guangzhou biological firebreak belt, investigated its plan and construction in recent years, carried on the appraisal to its quality and proposed its four construction departments:plan system, technical system, safeguard system and management system. This paper has done several aspects work as following:1 We comrehensively evaluated the growth, density and controlling area of Guangzhou biological firebreak belt.The results shows that:â‘ As a whole, growth situation of the constructed firebreak belt was poor.â… ,â…¡,â…¢andâ…£level accounted for 18.8%,17.0%,29.8% and 34.4% respectively. The qualified rate was only 65.6%.â‘¡Construction density of firebreak belt was lower than standard, and the quantity was insufficient too. The highest density was 29.0 m/hm2, and the lowest was only 3.6 m/hm2. The average density of Guangzhou forest belt was 6.8m/hm2, The average was 1.0%, which was greatly lower than other province's average levels, and greatly lower than the ratio of forest biological firebreak belt which was 5%-10%.â‘¢The layout of Guangzhou biological firebreak belt was relatively irrational, and the network system was not perfect. Distribution of biological firebreak belt was so fragmentary and dispersible that it can not able to form a closed circle.2 The whole planning length and area of biological firebreak belt in Guangzhou was 14,398.3km and 5741 hm2.â‘£According to managing types, biological firebreak belt was classified into construction type, reconstruction type and enhancing type, whose planning length was 1923.6km,669.9km and 1804.9km respectively, planning area of which was 2841 hm2,785 hm2,2115 hm2 respectively. According to managing aim, biological firebreak belt was classified into commercial forest, economic forest, scenic forest and shelter forest, whose planning length was 2064.8km,402.1km,79.3km and1882.0km respectively, planning area of which was 2699 hm2, 483 hm2,88 hm2and 2471 hm2 respectively. â‘¡Taking Guangzhou city as a overall area and district as a network area, four levels forest belt network system including area-division area(State forest Center)-small area-mesh was established, whose controlling area was 1000 hm2,200 hm2,100 hm2 and 10 hm2respectively, whose width was 30m,20m,15m and 10m respectively, whose density was over 14m/hm2 and reach the level of national standards.3 This paper suggests set up geographcial database of Guangzhou biological firebreak belt, which provides imformation in detail, accutely and directly.4 This paper proposes the guarantee system of biological firebreak belt, including policy, fund, land, constructive standards and etc.5 This paper is going to setting up technological system, including nursery stock, afforestation technology, tending management, prevention and control of plant dieases and elimination of pests.6 The deficiency is that the quality appraisal index of the Biological firebreak belt needs further consummation. This appraisal only uses three factors to carry on the present situation appraisal to the quality of the Biological firebreak belt.First, the appraisal indexes cannot reflect the quality condition of the Biological firebreak belt completely; second,it cannot carry on the dynamic appraisal.