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1.
黑龙江省1980—2005年森林火灾时空特征   总被引:4,自引:0,他引:4  
森林火灾是林火失去人为控制,在森林内自然蔓延和扩展,对生态系统和人类带来一定危害和损失的森林起火。森林火灾属世界性、跨国性的重大自然灾害,进入20世纪80—90年代以来,全球气候变暖导致森林火灾有上升的趋势,虽然各国的森林防火费用不断增加,但森林火灾发生的面积并未相  相似文献   

2.
We evaluated the spatial and temporal patterns of forest fires in two fire seasons (March to June and September to November) from 1996 to 2010 in Jilin Province, China, using the Canadian Forest Fire Weather Index System. Fire data were obtained from the Provincial Fire Agency, and historical climate records of daily weather observations were collected from 36 weather stations in Jilin and its neighboring provinces. A linear regression model was used to analyze linear trends between climate and fire weather indices with time treated as an independent variable. Correlation analysis was used to detect correlations between fire frequency, areas burned, and fire weather indices. A thin-plate smooth spline model was used to interpolate the point data of 36 weather stations to generate a surface covering the whole province. Our analyses indicated fire frequency and areas burned were significantly correlated with fire weather indices. Overall, the Canadian Forest Fire Weather Index System appeared to be work well for determining the fire danger rating in Jilin Province. Also, our analyses indicated that in the forthcoming decades, the overall fire danger in March and April should decrease across the province, but the chance of a large fire in these months would increase. The fire danger in the fall fire season would increase in the future, and the chance of large fire would also increase. Historically, because most fires have occurred in the spring in Jilin Province, such a shift in the future fire danger between the two fire seasons would be beneficial for the province’s fire management.  相似文献   

3.
Understanding both historic and current fire regimes is indispensable to sustainable forest landscape management. In this paper, we use a spatially explicit landscape simulation model, LANDIS, to simulate historic and current fire regimes in the Great Xing’an Mountains, in northeastern China. We analyzed fire frequency, fire size, fire intensity, and spatial pattern of burnt patches. Our simulated results show that fire frequency under the current fire scenario is lower than under the historic fire scenario; total area burnt is larger with lower fire intensity under the historic fire scenario, and smaller with higher fire intensity under the current fire scenario. We also found most areas were burned by high intensity fires under the current fire scenario, but by low to moderate fires under the historic fire scenario. Burnt patches exhibit a different pattern between the two simulation scenarios. Large patches burnt by high intensity class fires dominate the landscape under the current fire scenario, and under historic fire scenario, patches burnt by low to moderate fire intensity fires have relatively larger size than those burnt by high intensity fires. Based on these simulated results, we suggest that prescribed burning or coarse woody debris reduction should be incorporated into forest management plans in this region, especially on north-facing slopes. Tree planting may be a better management option on these severely burned areas whereas prescribed burning after small area selective cutting, retaining dispersed seed trees, may be a sound forest management alternative in areas except for the severely burned patches.  相似文献   

4.
The paper described the natural conditions and forest types in Northwestern Region of China. Most forests in the region are distributed in subalpine areas. It is important to protect the existent forests in the region for maintaining ecological balance. According to the statistics results of 1991~2000, the paper analyzes the forest fires distribution and fire severity. Annually the numbers of forest fires range from 52 to 240. The incidence rate of forest fires in Northwestern Region is under 0.33 per ten thousand ha. There are 0.67-64.4 ha burned area per ten thousand ha forest. The main reasons for forest fires lie in the dry weather conditions, many firebrands, and high fuel loading. The strategies of fire management in the region are to stress the fire education in forest regions, strength the firebrands' management, emphasize the fuel management, and improve the fire monitoring and fire control ability.  相似文献   

5.
Characterization of forest fires in Catalonia (north-east Spain)   总被引:1,自引:0,他引:1  
The present study analyses the temporal variation in the distribution of the number of fires, area burned and fire sizes in Catalonia using fire data from 1942 to 2002. The study shows variations in the distribution of fire size over recent decades, with a significant increase in the number of very large fires. The study also analyses relationships between characteristics of the forest (altitude, slope, aspect, living fuels and species composition) and the probability of the fire occurrence. The analysis is based on the overlay of forest cover data and perimeters of forest fires during the period (1986–2002). Of the analysed variables, altitude affects most the probability of fire occurrence, with higher proportions of burned forest area at lower altitudes. Stand’s vertical structure is also relevant, with lower proportions of burned area in stands with mature tree cover without understory. The study helps to analyse the strengths and weaknesses of forest and fire management policies, especially those related to forest and fuel management at the landscape level.  相似文献   

6.
凉山州是我省的森林火灾高发区,是四川省乃至全国森林火灾高危地区之一。通过对凉山州冕宁县近14年的森林火灾数据资料和气象数据资料分析,探讨了森林火灾次数与人为因素、气象因素、植被类型等因子的关系。结果表明:冕宁县森林火灾主要影响因素是人为因素,每年1—3月份是森林防火最重要的时段,云南松林区是区域森林火灾防范的重要区域。  相似文献   

7.
以湖南省为研究区域,分析冰雪后短期内(3月份)卫星热点的空间分布特征、与受害程度的空间关系,森林火灾发生的特点和扑火人员伤亡情况,以及气象因素对火发生的影响.结果表明:处于受害区确认为森林火灾的卫星热点占总数的61.00%.2008年3月份火灾次数和过火面积异常增高,共发生火灾3 097起,过火面积23 227.68 hm2,火灾次数超过1999-2007年3月份火灾次数的总和,且是1999-2007年3月份火灾次数总和的120.65%,3月份平均火灾次数的10.86倍.过火面积是1999-2007年3月份总和的88.40%,3月份平均过火面积的4.69倍.人员伤亡40人,是1999-2007年3月份人员伤亡总和的72.73%,平均伤亡人数的6.56倍.冰雪灾害后,2008年3月火灾次数、过火面积和人员伤亡人数的异常增高已经超出了气温和降水对火发生正常影响的范围.  相似文献   

8.
长沙县森林火灾发生规律研究   总被引:1,自引:0,他引:1  
根据长沙县"十一五"期间森林火灾发生的统计数据,从地域、时间、火因和肇事者等分析森林火灾发生的规律.结果表明:森林火灾发生存在明显的地域差异,据此可分为重灾区、较重灾区、较轻灾区、轻灾区和无灾区;森林火灾主要发生在防火期内,其中春防期明显多于冬防期,2月或3月为高发期,一天中的起火高峰在10:00—18:00;森林火灾发生主要由人为因素引起,森林火灾的肇事者老人最多,占30.6%。通过对森林火灾发生规律的调查分析,为长沙县"十二五"期间的森林火灾防控对策提出了建议。  相似文献   

9.
在“被动扑救森林火灾”向“以预防为主”的森林火灾预防机制转变过程中,通过对寅街镇20年来森林火灾发生规律、起火原因、地域和时间分布进行分析,指出93%属人为野外用火引起,森林火灾造成的经济损失主要为非生产性用火中故意纵火、外区烧入、上坟等造成的,野外火源是导致寅街镇森林火灾的主要原因。提出落实责任,加强宣传,完善巡查力度,实施计划烧除,抓好森林火灾保险,严格火源管理等寅街镇森林火灾预防对策及加强野外火源管理的_几点建议。  相似文献   

10.
林火动态变化对我国东北地区森林生态系统的影响   总被引:14,自引:0,他引:14  
我国积极的森林防火政策导致了我国东北林区的森林火周期延长,并影响到森林结构和可燃物组成的变化。火周期的延长会引起森林可燃物载量增加,并导致火频度、火灾类型和火强度发生改变。森林火周期延长还会引起大兴安岭地区云杉林的分布范围增大。植被的变化又对林火动态有反作用。为适应林火动态和可燃物的变化,我国东北林区森林防火政策需要作相应调整,采用林火管理思想开展森林防火工作。  相似文献   

11.
基于2003—2018年的中国森林火灾统计数据,全面分析了森林火灾发生的时空分布格局,定量分析了其统计学规律,旨在为森林火灾预测、管理和风险决策提供基础支撑。分析结果表明,森林火灾的发生具有极强的随机性和离散性,通过森林火灾总次数、火场面积和受害森林面积的平均数来反映森林火灾发生风险将会导致评估结果偏高。森林火灾发生次数较多的为湖南、贵州、广西等省,而森林火场面积和受害森林面积较多的为黑龙江、内蒙古、云南、湖南、广西等省。按照森林火灾发生的格局,运用K均值聚类分析将31省分为4类。  相似文献   

12.
云南松林区的林火与火险等级分区初探   总被引:1,自引:0,他引:1  
云南松林区发生的森林火灾是多种自然因素和人为活动综合作用的结果。通过对四川省云南松分布区不同区域与林火有关的主要气候因子分析及综合值的比较,结合地形地貌、植被状况和人为活动等多种因素,将我省云南松分布区划分成5个不同等级的火险区,并提出了相应的护林防火对策。  相似文献   

13.
Most of world's forests of different climates have a history of fire, but with different severities. Fire regimes for broadleaf deciduous forests have return intervals that vary from many decades (or less) to centuries (or more). Iran has a total of 1.2 million ha of temperate forest in the north, where fires burn about 300–400 ha annually. This study focused on the impact of fire on forest structure, tree species quality, and regeneration composition (specially beech) in the Chelir forest of northern Iran. The results showed that forest fires changed the structure and had different effects on tree species composition between burned and control areas. Thin barked species such as oriental beech (Fagus orientalis Lipsky) and coliseum maple (Acer cappadocicum Gled.) have been affected more than those with thick bark, like hornbeam (Carpinus betulus L.) and chestnut-leaved oak (Quercus castaneifolia C.A. Mey). The density of oriental beech regeneration in the unburned area was greater than in the burned area, while the quantity of regeneration of hornbeam, coliseum maple and velvet maple (Acer velutinum Boiss) was higher in burned area. Forest fire had a greater effect on oriental beech quality, and changed regeneration composition in the burned area. Fire prevention activities should be considered as a silvicultural treatment for preserving these valuable forests.  相似文献   

14.
Forest fires are influenced by several factors,including forest location, species type, age and density,date of fire occurrence, temperatures, and wind speeds,among others. This study investigates the quantitative effects of these factors on the degree of forest fire disaster using nonparametric statistical methods to provide a theoretical basis and data support for forest fire management.Data on forest fire damage from 1969 to 2013 was analyzed. The results indicate that different forest locations and types, fire occurrence dates, temperatures, and wind speeds were statistically significant. The eastern regions of the study area experienced the highest fire occurrence,accounting for 85.0% of the total number of fires as well as the largest average forested area burned. April, May, and October had more frequent fires than other months,accounting for 78.9%, while September had the most extensive forested area burned(63.08 ha) and burnt area(106.34 ha). Hardwood mixed forest and oak forest had more frequent fires, accounting for 31.9% and 26.0%,respectively. Hardwood-conifer mixed forest had the most forested area burned(50.18 ha) and burnt area(65.09 ha).Temperatures, wind speeds, and their interaction had significant impacts on forested area burned and area burnt.  相似文献   

15.
中国森林火灾发生规律及预测模型研究   总被引:1,自引:0,他引:1  
量化分析森林火灾发生规律能为预测和防治森林火灾提供科学依据。文中采用四参数Weibull分布描述了我国森林火灾发生次数和火场面积分布规律,运用Spearman相关系数分析承灾主体因子、灾害管理因子、孕灾环境因子与森林火灾发生次数、面积间关系,基于全国森林火灾数据分别建立灰色系统理论模型、BP人工神经网络模型和时间序列ARIMA模型,并采用Markov随机过程改进已建立模型。结果表明,我国森林火灾发生次数分布呈左偏正态分布,火场面积呈倒J型分布,火灾次数和火场面积分布模型拟合决定系数分别为0.63和0.66;承灾主体、孕灾环境和灾害管理对森林火灾次数和火场面积影响程度依次减小,人工林面积、累年年平均气温、年降雨量平均差值、年最低气温平均日数与森林火灾发生具有明显相关性,影响森林火灾的因子与森林火灾发生次数、火场面积间存在指数型关系;不同模型对森林火灾发生次数和火场面积拟合优度次序为BP模型、GM(1,1)-Markov模型、BP-Markov模型、GM(1,1)模型、ARIMA模型、ARIMA-Markov模型,采用Markov过程能显著改进GM(1,1)预测模型对火灾随机性的预测效果,可以更好地反映森林火灾发生规律。  相似文献   

16.
For efficient forest fire management, special precautions are required in dry and strong-wind seasons vulnerable to severe forest fires. To extract the seasonal characteristics of forest fires in South Korea, the statistics over the past 16 years, 1991 through 2005, were investigated. The daily records of the number of fire occurrences, the total area burned and the average burned area per occurrence were examined to identify the seasonal patterns of forest fires using cluster analysis and principal component analysis; the risk of daily fires was also assessed using the ordered logit model. As a result, the fire patterns were classified into five clusters and a general danger index for forest fires was derived from the first principal component, showing relatively large-scaled fire regimes in spring, and frequent small-scaled fire regimes in autumn and winter. In connection with the ordered logit model, the probability for the five ranks of forest fire risk was calculated and the threshold for high-risk fires was detected. As an implementation of the results above, the proper forest fire precautionary period in South Korea was estimated, and consequently October 21 through May 17 was recognized as a dry season at a high risk of forest fires. This period began 10 days earlier in autumn and extended into midwinter (late December and January) as opposed to the existing precautionary period, indicating the need of more cautious forest fire management earlier in autumn and continuing through midwinter.  相似文献   

17.
黑龙江省林火规律研究Ⅱ.林火动态与格局影响因素的分析   总被引:19,自引:0,他引:19  
胡海清  金森 《林业科学》2002,38(2):98-102
本文对在大尺度 (5 0 0km2 以上 )上影响黑龙江省林火的因素及其影响途径进行了分析。结果表明 ,年林火次数 (人为火次数 )与林业人口正相关 ,林火面积与人口无关。干燥度的空间差异对林火燃烧率格局有正向影响。林火特征与气候因子之间没有线性关系。黑龙江省林火次数和面积对年均温和降水量的响应可归纳为旋转的单叶双曲面和双叶抛物面两种模式。林火特征的周期与年均温、年降水量的周期关系很大。黑龙江省森林类型对林火次数、面积的影响在省级区划尺度上不显著的。较高的管理水平显著减少林火。林火次数、面积与了望塔数量、消防车数量及通讯覆盖率等无线性关系  相似文献   

18.
19.
It has been suggested that during the past several decades, the frequency and the intensity of wildfires have markedly increased in the Mediterranean basin. We came to assess this postulation in the forested region of Mount Carmel, Israel. This region is characterized by Quercus spp. and Pistacia spp. maquis and has been intensely afforested with Pinus spp. stands since the 1920s. We compiled a GIS-based database of the fires recorded in the region since 1983, in addition to archiving data beginning from the 1940s. The data were collected from land stewardship agencies’ archives, fire departments and aerial photographs. Prior to the early 1980s, no systematic documentation of the fires was available, rather just sporadic qualitative documentation of the large forest fires that occurred. Between 1944 and 1982, only 6 large fires were documented, while after that 11 large fires occurred. Analysis indicated that the spatial distribution of the fires does not occur at random, and their locations are significantly closer to roadsides compared to an expected random distribution. The annual number of fires and the areas burned during the last two decades were not correlated with annual precipitation in any manner. Accordingly, we suggest that the increased number of large forest fires during the last decades is associated with the maturation and senescence of the planted forest coupled with increased human activities.  相似文献   

20.
China is not rich in natural forest sources. Owing to natural and historical factors, forest fires have long been frequenting China. Forest fire prevention is the most important of all. Forest fire prevention and controlling have long been held as a very important factor in our ecological plans. Taking china 's special geographical location, topography, climate and the distribution of forest sources into consideration, we have every reason to believe that forest fires in China have their own special environment and occurrence. China suffers forest fire hazards heavily. Forest fires arise occasionally from thunderstruck or self-burning of peat. However, most fires are due to man's fault while inappropriately using fires in production and daily life. Since China is located in the Northern Hemisphere with a vast territory, there is a striking difference in the climate between South China and North China.  相似文献   

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