【作者】 赵文霞；

【导师】 杨宝君； 黄鹤羽；

【作者基本信息】 中国林业科学研究院 ， 森林保护学， 2008， 博士

【摘要】 我国是森林生物灾害发生最严重的国家之一。从可持续经营的角度考虑,森林生物灾害经济损失评估是政府、林业生产单位、林农急需解决的一个难题。因为,生产上所采取的一切减轻森林生物灾害的措施必须要考虑其经济效益和环境效益。此外,目前世界上以国家或地区为单位研究森林生物灾害经济损失的例子尚不多见。本文研究了森林生物灾害的定义、分类、分级、评估理论与方法。森林生物灾害由森林中的动物、植物和微生物引起,根据我国森林生物灾害致灾因子、灾害的表征、灾害引起的结果等特点,将其分为4种类型,即,生长量和生物量损失型、木材及林产品质量降低型、非木质林产品产量减少型、树木死亡型。将现有文献资料与森林生物灾害统计指标相结合,得出了不同种类有害生物的损失估算模型,将这些模型与各省2002—2006年的统计数据与森林生长特点和现状相结合,修正损失估算模型,并以省(自治区、直辖市)为单元,估算出各省(自治区、直辖市)及全国每年的生物灾害损失量。主要研究结论如下:1、将中国的森林生物灾害定义为以生态灾害为主、生态灾害和自然灾害并存的生物灾害;首次提出了不可避免性、周期性、渐变性、累积性、可预测性、可控性等森林生物灾害原理。2、推导出适合不同有害生物种类、不同森林类型的森林生物灾害实物量损失和价值量损失的计算公式,为全国及各省(自治区、直辖市)的森林生物灾害评估提供了基本的工具。3、森林生物灾害分为4种类型(1)生长(物)量损失型:由于致灾因子破坏或阻碍了植物的光合作用,导致树木生长量降低。主要致灾因子有食叶害虫、部分刺吸式及危害枝梢的害虫、叶部和嫩梢病害等。(2)质量降低型:由于致灾因子破坏树木的木质部,使木材的材积减少、质量下降。或由于致灾因子的危害,导致林产品质量下降。主要致灾因子有蛀干害虫,部分刺吸式及危害枝梢的害虫、种实害虫、种实病害、根部害虫、枝干病害、根部病害等。(3)产量减少型:由于致灾因子的直接或间接危害,导致人类需要的非木质林产品减少。主要致灾因子有种实害虫、种实病害、食叶害虫、枝干病虫害等。(4)树木死亡型:导致整株或成片树木死亡,是最严重的灾害类型。主要致灾因子有危害韧皮部和树皮的害虫、维管束病害,部分根部害虫、蛀干害虫、枝梢害虫、枝干病害、啮齿动物等。4、灾害的分级将受灾面积、成灾面积、灾害影响范围、直接经济损失值4个指标作为森林生物灾害损失定量评估的绝对指标,以成灾面积占森林总面积的比值、直接经济损失占(当地)GDP的比值作为森林生物灾害损失定量评估的相对指标。根据全国森林生物灾害实际发生的历史数据和简便性原则,将灾害等级分为4级:巨灾、大灾、中灾、微灾。巨灾的标准为年受灾和成灾面积10万hm~2以上,直接经济损失亿元人民币以上,全国范围危害;年受灾和成灾面积1～10万hm~2,直接经济损失1000万元以上,影响区域或流域的属于大灾;年受灾和成灾面积0.1～1 hm~2,直接经济损失100～1 000万元,在各省范围内危害的,属于中灾;微灾指年受灾和成灾面积小于1 000 hm~2,直接经济损失小于100万元,局部危害的灾害。5、全国森林生物灾害直接经济损失评估结果(1)2002—2006年我国森林生物灾害(不包括西藏自治区、台湾省、香港特别行政区、澳门特别行政区的数据)年受灾面积平均为950万hm~2,占全国林业用地面积的3%,年成灾面积平均为400万hm~2,成灾率42.57%;年材积损失量平均为2 200万m~3,占全国活立木蓄积量的0.1%;非木质林产品平均年产量损失为89万t;木材、竹材、非木质林产品年价值损失量达329亿元人民币。(2)松毛虫年平均年受灾面积为130万hm~2,占森林生物灾害总受灾面积的13.2%,年成灾面积平均为490万hm~2,占森林生物灾害总成灾面积的12.2%,年材积损失量平均为207万m~3,占森林生物灾害总损失量的9%左右,年松脂产量损失平均为73t,其材积和松脂总价值损失量占森林生物灾害价值损失量的3 %左右。杨树蛀干害虫和食叶害虫的年受灾面积占森林生物灾害总面积的8%～12%,价值损失量占森林生物灾害总损失量的1%左右。更多还原

【Abstract】 China is one of the countries bearing the most forest bio-disaster damages and losses in the world. From forest sustainable management view, the results of economic losses evaluation is urgently desired by farmers, forest managers and governments at different level, for they need to balance control costs and economic impacts of the disaster. They also need to know if their control measurements can have non-harmful impact on environment. Up to now, there are little research data for estimating economic losses of forest bio-disaster at nation or region level.In this paper, the definition, classification, rank, evaluation theory and methods for forest bio-disaster were studied. Forest bio-disaster is caused by animals, plants and microorganisms in forests. It was classified as 4 types according to the causes, symptomatology and the disaster performance. The direct economic losses mainly include live tree growth deduction, timber volume losses and grade decline, non-wood products losses and grade decline. Calculating equations and formulations for estimating forest bio-disaster were deduced by the combination of China forest pest statistic criteria and loss assessment data of different single forest pest, emending with pest statistic data, forest growth data and non-wood forest products data during 2002-2006 in different provinces. The main results of this paper were showed as follows:The essence of China’s forest bio-disaster The forest biodisaster in China is a kind of ecological disaster mixed with natural elements. Irrational management of forest is the main cause of the disaster. Forest bio-disaster theory was put forward such as inevitability, periodicity, non-paroxysmic, accumulative, predictible and controllable.Calculating for the loss of forest biodisaster 62 sets of calculating equations and formulations for estimating losses of forest bio-disaster were deduced which will provide tools for China every provinces.Forest bio-disaster were classified as 4 typesⅰ)Forest growth deduction. The causes of the disaster, including defoliators, scales and aphids, shoot damagers, foliage and shoot diseases pathogen, blocked or destroyed photosynthesis of the plants.ⅱ)Timber grade declined. The causes of the disaster, including borers, scales and aphids, root damagers, trunk and root diseases, destroyed the xylem of the plants.ⅲ)Non-wood forest products losses. The causes of the disaster, including tree seed and cone pests, diseases and insect pests damaging economic forests, destroyed seed and cones as well as economic forests.ⅳ)Tree death. The causes of the disaster, including bark and phloem damagers, root diseases and insect pests, tree borers, trunk diseases,vascular damagers and rodents, gave rise to the collapse of a tree or forest.Forest bio-disaster rank Forest bio-disaster can be ranked as 4 grades—gigantic disaster, great disaster, medium disaster and little disaster by 4 kinds of absolute criteria and 2 kinds of relative criteria. The absolute criteria include infested areas, damaged areas, incidence and direct economic losses. The relative criteria are the ratio of the damaged areas to forest areas and the direct economic losses to GDP in the occurred region. Gigantic disaster means that the annually infested and damaged areass exceed 100 thousand hectares, the direct economic losses more than RMB 100 million Yuan and the incidence relating to the whole country. Great disaster indicates that the annually infested and damaged areas between 10-100 thousand hectares, the direct economic losses between RMB10-100 million Yuan and the incidence relating to more than one drainage areass or cross provinces. The infested and damaged areas, the direct economic losses and the incidence for medium disaster was defined as 1-10 thousand hectares, RMB 1-10 million Yuan annually and within a province, respectively. Little disaster was that the annually affected and damaged areas no more than 1000 hectares, loss less than RMB 1 million Yuan and the incidence at local level.The results of the estimationⅰ)The infested areas of forest bio-disaster during 2002-2006 (not include Tibet, Taiwan, Hongkong, Makao data ) was 9.5 million hectares per year, occupied 3% of the total forest areas in China. The damaged areas occurred 4 million hectares annually and the damage ratio was 42.57%. The average timber volume loss was 22 million cubic meters per year, occupied 0.1% of living forest stand volumes in China. The annually non-wood forest products losses was 890 million kg and the total loss values of timber, bamboo and non-wood forest products was RMB 32.9 billion Yuan.ⅱ)The infested areas of pine caterpillars was 1.3 million hectares, occupied 12.3% that of the total forest bio-disaster infested areass. The average timber volume loss was 2070 thousand cubic meters per year, occupied 9% of the total timber losses of forest bio-disaster in China. The annually resin harvest loss was 73 thousand kg and the total loss values of timber and resin was 3 % of the total loss values caused by forest bio-disaster in China. The infested and damaged areas of poplar defoliators and borers were in the range of 8%-12% that of the total forest bio-disasters in China, but the economic value losses is only 1% of the total.更多还原