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1.
石凤伟 《绿色科技》2014,(5):229-230
根据景谷县2004~2013年发生森林火灾次数、火场总面积、受害森林面积、损失林木数量、火源等具体数据,应用统计分析方法,对全县森林火灾发生规律与趋势进行了初步分析,结果表明:景谷县近10年来共发生森林火灾38次,森林火场面积1065.425hm2,受害森林面积202.443hm2,损失林木7675m3、损失幼木22.3986万株;未发生重大、特大森林火灾,森林火灾次数有缓慢减少的趋势;一旦发生森林火灾,火场面积和受害森林面积有缓慢增加的趋势,损失林木有增加的趋势。针对当前存在的问题,提出了相应的建议。  相似文献   

2.
森林火灾次数下降64%,受害森林面积下降80%,伤亡人数下降78%据国家森林防火指挥部4月4日消息,今年第一季度,全国共发生森林火灾1106起,主要发生在四川、湖南、云南、贵州和湖北等省,其中一般森林火灾772起,较大森林火灾334起,没有重大、特别重大森林  相似文献   

3.
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   

4.
1950-2010年中国森林火灾时空特征及风险分析   总被引:6,自引:0,他引:6  
[目的]开展森林火灾时空特征和风险分析,有利于把握森林火灾发生规律,为预测和防治森林火灾、制定差异化森林火灾财政补贴和保险政策提供科学依据.[方法]根据年鉴数据,借助主成分分析、聚类分析和信息扩散理论,对我国1950-2010年森林火灾的时空分布特征和风险状况进行研究,全面分析森林火灾发生的时空特征,结合灾情指标对全国各省进行评价并分类,并定量分析风险水平.[结果]1)1950-2010年间,年均发生火灾12 683次,年均火场面积67.48万hm2,年均火灾次数和火场面积均呈下降趋势;1988-2010年间年均成灾面积7.95万hm2,总体表现为上升趋势;1988-2010年间年均成林蓄积损失167.5万m3,没有明显年际变化;1988-2010年间年均伤亡214人,总体呈波浪式下降趋势.2)人为火源占已查明火源的80%以上,烧荒烧炭是最主要的生产性用火火源(38.47%),上坟烧纸是最主要的非生产性用火火源(19.92%).3)华东、西南地区相比于其他地区火灾次数明显较大,东北地区火场面积明显较大.4)按照一般和较大火灾次数、重大和特大火灾次数、火场面积、受害森林面积、成林蓄积、幼林株数、受伤人数、死亡人数8个指标,通过主成分分析对31个省(区、市)的火灾状况进行评价并排序,然后根据主成分得出的综合得分进行聚类分析,根据受灾程度将31个省区按照严重、较重、中度、一般和轻度分为5类,其中,湖南受灾最严重,其次是黑龙江、贵州和云南等.5)基于信息扩散理论进行森林火灾风险分析,全国每年发生3 000 ~9 000次一般和较大火灾的概率较大(> 0.482 4),每年发生0~30次重大和特大火灾概率较大(>0.430 2),每年受灾森林面积在15万hm2以下概率较大(>0.407 2).[结论]我国森林火灾频发、面积大,火灾高发与气候变化息息相关.引发森林火灾的主要原因是人为火源,必须严格控制和管理野外火源,规范生产、生活用火行为.森林火灾具有显著的区域性特征,我国森林资源面临的火灾风险压力较大.建议在准确把握全国森林火灾时空分布特征和风险基础上,加强宣传教育,采取科学的森林防火、预报、监测措施,制定合理的森林火灾财政补贴和森林保险政策,维护森林健康和国家生态安全.  相似文献   

5.
<正>一、林业主要灾情一是森林火灾频发不断。截至3月4日,全省共发生森林火灾370起,受害面积1927公顷,火灾次数和受害面积同比分别上升52%、32%。缅甸山火3次烧入我省境内,多个火场对我方构成威  相似文献   

6.
文中介绍了我国2000—2012年森林火灾发生的整体情况,分析了我国夏季森林火灾的时空分布规律。2000一2012年我国森林火灾发生次数年际间大体保持平稳,2003—2005年达到一个较高的峰值,2008年达到最高峰,近几年来则呈下降趋势。夏季森林火灾的发生次数在2000—2007年处于较高水平,尤其是2003年和2006年火灾发生次数最多,而近5年来则处于较低水平并有下降的趋势。我国华中地区和西南地区发生夏季森林火灾次数最多,而东北地区重、特大森林火灾发生最多。我国夏季森林火灾具有等级高、破坏性大、火场面积和受害森林面积较大等特点。  相似文献   

7.
我简要通报一下今年全国春、夏季森林防火工作情况,并就下一步森林防火工作规范化建设,以及此次会议的贯彻落实提出安排意见。1春、夏季森林防火工作情况今年上半年,全国共发生森林火灾9659起,其中森林火警5529起,一般火灾4117起,重大森林火灾13起,火场总面积12.4万hm2,受害森林面积4万hm2,森林火灾受害率0.24‰,因灾死亡84人。与去年同期相比,取得了“三降”、“两减”、“双无”的好成绩。即森林火灾次数下降18.5%,火场总面积下降5.2%,受害森林面积下降34.7%;森林火灾受害率减少0.13‰,死亡人数减少29.4%;无特大森林火灾,无重大人员伤亡事…  相似文献   

8.
2011年,广西采取有力措施狠抓森林防火工作,取得明显成效,全区森林火灾同比减少五成。据统计,全区全年共发生森林火灾350起,其中一般火灾171起,较大火灾179起,无重、特大森林火灾;火场总面积5072公顷,受害森林面积883公顷,森林火灾受害率0.064%c,比2010年减少0.056个千分点;森林火灾当日扑灭率98%。  相似文献   

9.
据.1月17日在南宁召开的全国林火统计汇总审核评比会的汇总,1993年全国林火次数比上年下降34.7%,受害森林面积下降54.3%,全年森林火灾受害率0.194‰;发生重大森林火灾6次,没有发生特大森林火灾。森林火灾受害率低于0.100‰以下的有18个省、自治区、直辖市,我区为0.094‰。  相似文献   

10.
新时期广西森林防火工作新机制探略   总被引:1,自引:0,他引:1  
韦丹 《广西林业》2008,(5):38-39
广西是一个森林火灾多发的省区,据统计,1950年到1987年全区年均发生森林火灾1843起,受灾森林面积49514公顷。1987年以后,在普遍建立森林防火办事机构的基础上,广西狠抓了各类形式的专业森林消防队伍建设,使森林火灾多发的势头得到了明显遏制,森林火灾次数年均下降了68%,受害森林面积年均下降了93%.  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
17.
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   

18.
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   

19.
利用2001~2009年黑龙江省夏季林火资料和同期林区气象观测资料,采用主成分分析方法确定了月降水量和月无雨日数、月平均温度及14时月平均风速是影响夏季林火的关键因子,其中降水量是最重要的影响因子,其次是温度因子和动力因子,夏季的温湿状况以及动力条件是决定夏季林火是否发生的关键;根据温湿因子综合分析发现,夏季林火多发生在暖干型气候背景下,即气温高降水少的月份,而且这种形势下发生的火灾往往持续时间长、过火面积大、造成的损失严重。  相似文献   

20.
Forest fires caused by natural forces or human activities are one of the major natural risks in Northeast China. The incidence and spatial distribution of these fires vary over time and across the forested areas in Jilin Province, Northeast China. In this study, the incidence and distribution of 6519 forest fires from 1969 to 2013 in the province were investigated. The results indicated that the spatiotemporal distribution of the burnt forest area and the fire frequency varied significantly by month, year, and region. Fire occurrence displayed notable temporal patterns in the years after forest fire prevention measures were strictly implemented by the provincial government. Generally, forest fires in Jilin occurred in months when stubble and straw were burned and human activities were intense during traditional Chinese festivals. Baishan city, Jilin city, and Yanbian were defined as fire-prone regions for their high fire frequency. Yanbian had the highest frequency, and the fires tended to be large with the highest burned area per fire. Yanbian should thus be listed as the key target area by the fire management agency in Jilin Province for better fire prevention.  相似文献   

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