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1.
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
2.
3.
《林业研究》2019,(6)
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
4.
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
5.
气候变化背景下森林火灾发生规律研究 总被引：2，自引：0，他引：2
随着气候变暖加剧，全球森林火灾灾害发生的频率与强度亦随之增加，世界各地森林火灾潜
在的危险将长期存在，严重程度也将大幅增加。森林火灾对森林生态资源和全球气候产生了重大影响，
由于其突发性强、破坏性大、处置救助极为困难，是当今世界最为严重的生态灾害和突发性公共事件之
一。森林火灾发生发展规律是森林火灾预防与扑救的重要依据，加强其规律研究有利于有的放矢地开展
森林防灭火工作。针对气候变化现状及发展态势，结合气候变化背景下国内外森林火灾现状，系统论述
了气候变化对我国森林火灾发生发展规律的影响，主要阐述了气象条件影响森林火灾的发生，气候影响
森林可燃物，气候影响森林火源，气象影响森林火行为，气候决定森林火灾周期以及气候变化对森林火
灾时空分布规律的影响。在全球气候变暖的背景下，从解析我国森林火灾发生规律入手，通过气候变化
背景下我国森林火灾发生规律的研究，客观认识我国和各地区森林火灾发生发展规律，从而为国家和地
方各级政府有效开展森林火灾灾害防治和应急管理工作、切实保障社会经济可持续发展提供科学决策
依据。 相似文献
6.
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
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
7.
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
8.
Abbas Banj Shafiei Moslem Akbarinia Gholamali Jalali Mohsen Hosseini 《Forest Ecology and Management》2010
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
9.
The subject of risk management is attracting more and more attention around the world. The risk of forest fire disasters should
be faced and dealt with for forest fires cannot be avoided. Treating forest fire disasters as a risk management issue promotes
important measures and methods for fire fighters to prevent, reduce and control the risks of forest fires. In this paper,
the risk concept and risk connotation as well as the management risks for forest fire suppression are discussed clearly. Issues
such as risk judgments, risk analysis, risk control and the assessment of risk, including their contents and corresponding
methods are clarified.
Translated from Forest Resources Management, 2006, 2: 24–27 [译自: 林业资源맜理] 相似文献
10.
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
11.
SHU Lifu TIAN XiaoruiResearch Institute of Forest Ecology Environment Protection. Chinese Academy of Forestry. Beijing China 《中国林业科技(英文版)》2002,(3)
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
12.
13.
Analysis of the seasonal characteristics of forest fires in South Korea using the multivariate analysis approach 总被引：2，自引：0，他引：2
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
14.
【目的】通过地理加权回归(GWR)模型估算非干扰林龄,利用遥感数据和林火发生历史数据,获取过火区域信息,进而对林火烈度分级,讨论林火烈度与森林类型的交互作用,估算干扰林龄,最终获得黑龙江省森林年龄的空间分布。【方法】以黑龙江森林为研究区域,基于研究区域的多光谱数据结合地面森林资源清查数据,通过逐步回归方法提取了包括遥感因子绿度指数(Greeness)、湿度指数(Wetness)、林分平均胸径(ADBH)、林分平均树高(ASH)及海拔(Altitude)在内的5个显著因子作为自变量,采用GWR模型建立非干扰林龄估算模型。采用全局Moran I来描述模型残差的空间自相关性。绘制研究区非干扰林龄空间分布图并探究林龄的空间分布状态。[JP+1]结合林火位置与面积记录对多光谱数据目视解译提取过火区域,根据dNBR将过火区域火烈度分级。将火烈度图与植被类型图叠加分析,讨论不同森林类型在不同火烈度下的演替情况。定义干扰林龄时,未发生树种更替的森林林龄不变,树种发生更替的森林在林火发生年将其林龄归为0,并在新的优势树种萌发时从1开始累加,以此类推干扰后森林的林龄。【结果】黑龙江省非干扰森林平均林龄为48年,标准差为16年。GWR模型的 Radj^2 为0.68,RMSE为16.171 7。使用Moran I来检验模型的残差,发现GWR模型可很好地消除残差的空间自相关性。研究区林龄整体空间分布状态不均匀,大兴安岭地区林龄普遍高于黑龙江林区。黑龙江省2000―2010年林火主要发生在大兴安岭及小兴安岭地区,根据dNBR将已提取的过火区域林火烈度分为:未过火、轻度过火、中度过火和重度过火4类,总过火面积为527 932 hm^2,其中重度29 157 hm^2、中度180 268 hm^2、轻度318 507 hm^2。兴安落叶松林和蒙古栎林在整个研究区中过火面积最大,分别占总过火面积的28.63%和47.23%。根据不同森林类型在不同火烈度下的演替情况,估算干扰森林的林龄并绘制干扰林龄空间分布图。【结论】 GWR模型能较有效地估算黑龙江省非干扰林龄,成功地降低了残差的空间自相关性。在估算林龄的过程中加入林火干扰因素,以获取更真实的林龄空间分布数据,可为黑龙江地区森林NPP、NEP以及森林碳储量、森林生物量等相关研究提供数据支持。 相似文献
15.
【目的】通过地理加权回归(GWR)模型估算非干扰林龄,利用遥感数据和林火发生历史数据,获取过火区域信息,进而对林火烈度分级,讨论林火烈度与森林类型的交互作用,估算干扰林龄,最终获得黑龙江省森林年龄的空间分布。【方法】以黑龙江森林为研究区域,基于研究区域的多光谱数据结合地面森林资源清查数据,通过逐步回归方法提取了包括遥感因子绿度指数(Greeness)、湿度指数(Wetness)、林分平均胸径(ADBH)、林分平均树高(ASH)及海拔(Altitude)在内的5个显著因子作为自变量,采用GWR模型建立非干扰林龄估算模型。采用全局Moran I来描述模型残差的空间自相关性。绘制研究区非干扰林龄空间分布图并探究林龄的空间分布状态。[JP+1]结合林火位置与面积记录对多光谱数据目视解译提取过火区域,根据dNBR将过火区域火烈度分级。将火烈度图与植被类型图叠加分析,讨论不同森林类型在不同火烈度下的演替情况。定义干扰林龄时,未发生树种更替的森林林龄不变,树种发生更替的森林在林火发生年将其林龄归为0,并在新的优势树种萌发时从1开始累加,以此类推干扰后森林的林龄。【结果】黑龙江省非干扰森林平均林龄为48年,标准差为16年。GWR模型的 Radj^2 为0.68,RMSE为16.171 7。使用Moran I来检验模型的残差,发现GWR模型可很好地消除残差的空间自相关性。研究区林龄整体空间分布状态不均匀,大兴安岭地区林龄普遍高于黑龙江林区。黑龙江省2000―2010年林火主要发生在大兴安岭及小兴安岭地区,根据dNBR将已提取的过火区域林火烈度分为:未过火、轻度过火、中度过火和重度过火4类,总过火面积为527 932 hm^2,其中重度29 157 hm^2、中度180 268 hm^2、轻度318 507 hm^2。兴安落叶松林和蒙古栎林在整个研究区中过火面积最大,分别占总过火面积的28.63%和47.23%。根据不同森林类型在不同火烈度下的演替情况,估算干扰森林的林龄并绘制干扰林龄空间分布图。【结论】 GWR模型能较有效地估算黑龙江省非干扰林龄,成功地降低了残差的空间自相关性。在估算林龄的过程中加入林火干扰因素,以获取更真实的林龄空间分布数据,可为黑龙江地区森林NPP、NEP以及森林碳储量、森林生物量等相关研究提供数据支持。 相似文献
16.
Estimation of fire severity by use of Landsat TM images and its relevance to vegetation and topography in the 2000 Samcheok forest fire 总被引：1，自引：0，他引：1
Byungdoo Lee Seon Young Kim Joosang Chung Pil Sun Park 《Journal of Forest Research》2008,13(4):197-204
The severity of the 2000 Samcheok forest fire was classified by using Landsat TM images, and the effects of vegetation structures
and topographic conditions on fire severity were analyzed. The estimated normalized difference vegetation index differences
between the pre and post-fire Landsat TM images were used as the criteria in determining the levels of fire severity–low,
moderate, and extreme. According to the results from fire severity estimation, of the 10,600 ha forest stands, 28% was severely
damaged by crown fires, 38% was moderately damaged, and the remaining 34% was damaged slightly by surface fires. The overall
accuracy of the fire severity classification was 83% (Kappa coefficient = 0.76). The results of χ
2-tests showed that fire severity differed significantly with the vegetation and topographic conditions as follows. The coniferous
stands, compared with the mixed and broad-leaved, were more vulnerable to fire damage; the higher the slope of fire sites,
the greater the fire damage; the south was the most vulnerable aspect; fire severity of coniferous forest stands increased
with increasing elevation. However, in the study area it was found that fire severity of broad-leaved forest stands were negatively
related to the elevation of the corresponding fire sites and affected more by vegetation conditions rather than by topographic
conditions. 相似文献
17.
Choonsig Kim Won-Kyu Lee Jae-Kyung Byun Young-Kul Kim Jin-Hyun Jeong 《Journal of Forest Research》1999,4(1):23-25
This study was performed to investigate a short time change (one week after fire) on soil properties due to the fire inPinus densiflora Sieb. et Zucc stands of the Kosung area in Kangwon Province in Korea. Twenty seven sampling plots [16 burned (8 low intensity
fire, 8 high intensity fire) and 11 unburned plots] were chosen. Mineral soil samples from three depths (0–5, 5–15, and 15–25
cm) under the forest floor were collected. Forest fire in the area affected soil chemical properties. Soil pH, total nitrogen,
available phosphorus, potassium, calcium, and magnesium in the surface soil (0–5 cm) of the burned area compared with the
unburned area increased, but there was no marked change in the subsurface soil (5–25 cm). Organic matter, total nitrogen,
available phosphorus, and exchangeable cations in the surface soil were generally lower in the high than in the low intensity
fire areas. This indicates that these nutrients on the high intensity fire may be volatilized. The results suggest that change
in soil chemical properties in the area was restricted mainly to the surface soil and was different between the high and the
low intensity fire types. 相似文献
18.
C. Lampin-Maillet M. Long-FournelA. Ganteaume M. JappiotJ.P. Ferrier 《Forest Ecology and Management》2011,261(12):2200-2213
Each year, forest fires destroy about 500,000 ha of vegetation in Europe, predominantly in the Mediterranean region. Many large fires are linked to the land transformations that have taken place in the Mediterranean region in recent decades that have increased the risk of forest fires. On the one hand, agricultural fallows and orchards are slowly being colonized by vegetation, and on the other hand, the forest is not sufficiently used, both of which result in increased accumulation of fuel. In addition, urbanization combined with forest extension results in new spatial configurations called “wildland-urban interfaces” (WUI). WUI are commonly defined as “areas where urban areas meet and interact with rural lands, wildland vegetation and forests”. Spatial analyses were performed using a WUI typology based on two intertwined elements, the spatial organization of homes and the structure of fuel vegetation. The organization of the land cover in terms of representativeness, complexity or road density was evaluated for each type of WUI. Results showed that there were significant differences between the types of WUI in the study area. Three indicators (i) “fire ignition density”, derived from the distribution of fire ignition points, (ii) “wildfire density”, derived from the distribution of wildfire area and (iii) “burned area ratio”, derived from the proportion of the burned area to the total study area were then compared with each type of WUI. Assuming that the three indicators correspond to important aspects of fire risk, we showed that, at least in the south of France, WUI are at high risk of wildfire, and that of the different types of wildland-urban interfaces, isolated and scattered WUI were the most at risk. Their main land cover characteristics, i.e. low housing and road densities but a high density of country roads, and the availability of burnable vegetation such as forested stands and shrubland (garrigue) explain the high fire risk. Improving our knowledge of relationships between WUI environments and fire risk should increase the efficiency of wildfire prevention: to this end, suitable prevention actions and communication campaigns targeting the types of WUI at the highest risk are recommended. 相似文献
19.
The Santa Fe municipal watershed provides up to 40% of the city's water and is at high risk of a stand-replacing fire that could threaten the water resource and cause severe ecological damage. Restoration and crown fire hazard reduction in the ponderosa pine (PP) forest is in progress, but the historic role of crown fire in the mixed-conifer/aspen (MC) and spruce-dominated forests is unknown but necessary to guide management here and in similar forests throughout the southwestern United States. The objective of our study was to use dendroecological techniques to reconstruct fire history and fire–climate relationships along an elevation, forest type, and fire regime gradient in the Santa Fe River watershed and provide historical ecological data to guide management. We combined systematic (gridded) sampling of forest age structure with targeted sampling of fire scars, tree-ring growth changes/injuries, and death dates to reconstruct fire occurrence and severity in the 7016 ha study area (elevation 2330–3650 m). Fire scars from 141 trees (at 41 plots) and age structure of 438 trees (from 26 transects) were used to reconstruct 110 unique fire years (1296–2008). The majority (79.0%) of fires burned during the late spring/early summer. Widespread fires that scarred more than 25% of the recording trees were more frequent in PP (mean fire interval (MFI)25% = 20.8 years) compared to the MC forest (31.6 years). Only 24% of the fires in PP were recorded in the MC forest, but these accounted for a large percent of all MC fires (69%). Fire occurrence was associated with anomalously wet (and usually El Niño) years preceding anomalously dry (and usually La Niña) years both in PP and in the MC forest. Fire in the MC occurred during more severe drought (mean summer Palmer Drought Severity Index; PDSI = −2.59), compared to the adjacent PP forest (PDSI = −1.03). The last fire in the spruce forest (1685) was largely stand-replacing (1200 ha, 93% of sampled area), recorded as fire scars at 68% of plots throughout the MC and PP forests, and burned during a severe, regional drought (PDSI = −6.92). The drought–fire relationship reconstructed in all forest types suggests that if droughts become more frequent and severe, as predicted, the probability of large, severe fire occurrence will increase. 相似文献
20.
林火的干扰在北方森林生态系统更新演替、物质循环中发挥着重要的作用,林火对北方地区森林表层土壤碳密度、生物量有着明显的改变作用,然而有关较深土层（≤40 cm）的碳储量变化情况研究相对较少。以辽西地区油松林火烧迹地作为调查样地,通过对周边立地条件一致的未发生火灾的林区作为对照,以土壤物理性质、碳储量作为指标开展调查分析,结果表明,油松林火烧迹地土壤的物理性质、碳元素含量发生了不同程度的变化,林火显著增加了土壤的温度和pH值,极显著降低了土壤的含水量;林火对深层土壤容重的影响不明显;火烧迹地上深层土壤全碳含量、可溶性有机碳含量均极显著低于对照处理。 相似文献