首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 515 毫秒
1.
Local to global perspectives on forest and land fires in Southeast Asia   总被引:1,自引:0,他引:1  
Forest and land fires are not new to the landscapes of Southeast Asia. Nevertheless, strikingly different perspectives persist about the significance of fires in the tropics to environmental changes and human well-being and consequently how they should be managed. Our synthesis of papers in this special issue suggests both trade-offs and complementarities in various policy responses with differing objectives. There are, however, at least three domains with high potential of meeting multiple objectives. First, is through identification, and improved management, of ecosystems vulnerable to fire under current and future climate. Agriculture, forestry and human settlements on peat land areas in Indonesia are candidates for such a focus. Second, is through building adaptive capacities to manage fire and related land and water resources. Investments in capacity at multiple levels are needed, but particularly at fairly local levels where stakeholders have strong incentives to manage fires appropriate to local contexts. Third, is through building awareness that fire management does not universally equate to fire suppression. Severe smoke haze episodes, for example, are also a result of timing of fires, and some fire-adapted ecosystems may depend on fire to persist. Finally, we emphasize that effective fire management is unlikely to be realized without greater engagement by research and policy with stakeholders in thoroughly exploring the full range of land and fire management options. Negotiation, compensation and trade-offs are probably inevitable.  相似文献   

2.
Numerical modelling of fire-related smoke haze episodes in Southeast Asia is important for both prediction and assessment of atmospheric impacts, especially when observational data are fragmentary, as is the case in Indonesia. This work describes the atmospheric fate of smoke particles emitted during the 1997 Indonesian fires modelled with a regional atmospheric chemistry model. We established a new fire emission inventory and calculate that 55 teragram (Tg) of particulate matter and 1098 Tg of carbon were released during this fire episode. Our emission estimate is an intermediate value compared with other studies. Utilising different scenarios, we demonstrate the variable atmospheric impacts of surface vegetation fires and peat soil fires separately and also investigate the sensitivity of smoke dispersion to the differing meteorological conditions of an El Niño and a normal year. When peat fires are included in the emission inventory, modelled ambient particle concentrations exceed the ambient air quality standard across transboundary scales. In a scenario including only surface vegetation fires, ambient air quality standards are exceeded only in areas close to the main fires. This scenario demonstrates the prominent role of fires in peat areas in causing regional air pollution episodes. In years with normal meteorological conditions, intermittent precipitation and associated wet deposition during the dry season are predicted to remove most of the particulate emissions close to the sources. Strongly reduced rainfall and generally stronger southeasterly winds during El Niño years provide favourable conditions for larger scale smoke haze pollution.  相似文献   

3.
As part of the Russian FIRE BEAR (Fire Effects in the Boreal Eurasia Region) Project, replicated 4-ha experimental fires were conducted on a dry Scotch pine (Pinus sylvestris)/lichen (Cladonia sp.)/feathermoss (Pleurozeum schreberi) forest site in central Siberia. Observations from the initial seven surface fires (2000-2001) ignited under a range of burning conditions quantified the different fuel consumption and fire behavior characteristics (e.g., rate of spread, fireline intensity, etc.) possible in this particular forest fuel type. Experimental results and dendrochronological study of local fire history both support the dominance of local fire regimes by low to moderate-intensity surface fires. Carbon released by the experimental fires ranged from 4.8 to 15.4 t C ha− 1 depending on fuel conditions and fire severity. Preliminary emission data show a strong correlation between carbon dioxide (CO2) and carbon monoxide (CO) emissions, which should facilitate accurate estimates of fire impacts on atmospheric chemistry. Carbon concentration in smoke samples was related to fire severity. The short landscape-scale fire-return interval (50 years), combined with typically low fire severity, in pine ecosystems of central Siberia is often associated with low tree mortality and relatively rapid buildup of litter and understory fuels after a fire.  相似文献   

4.
There was a widespread misconception about the causes of vegetation and land fires in Indonesia. At a certain point, the public perceived that fires and the associated haze pollution were primarily caused by smallholders' agricultural activities. In fact, there was a variety of land-use activities including large-scale land clearing following deforestation for further land development. El Niño events and the associated dry weather were sometimes quoted by officials and the media as the cause of fires. The fire episodes from 1980 to 2000 were analysed in connection with climate anomalies and the implementation of land-use policies related to forest conversions. The analysis employs long-term climatic and sea surface temperature data to reconstruct climate distributions and anomalies including Southern Oscillation Index (SOI), Sea Surface Temperature (SST) and Outgoing Long-wave Radiation (OLR). In this study, the terrestrial carbon emissions from vegetation fires were estimated based on official statistical data on area burnt. The possible incentives for sustainable land management were discussed in the light of fire prevention. The underlying cause neglected in the discussion of Indonesian vegetation fires was forest and land development policy. Legitimated in the early 1980s, it drove massive forest conversions and the use of fires for land clearing. El Niño Southern Oscillation (ENSO) provided dry weather suitable for biomass burning and widespread fire, but it was hardly the cause of fires. The estimate of area burnt in the big fires in 1997 was about 11.6 Mha, resulting in carbon release of 1.45 Gt, equivalent to 0.73 ppmv of CO2, or almost half the annual global atmospheric CO2 growth. Based on the current carbon market price such emissions by the 1997 fire episode were worth around US$ 3.6 billion.  相似文献   

5.
Transboundary haze pollution from smoke from land preparation fires has become a perennial problem in Indonesia, especially in the last 10 years during the dry season. Most of that smoke originates from illegal land preparation fires for oil palm and industrial forest plantation as well as from shifting cultivation, which is usually blamed for the smoke. In order to understand the role of fire in shifting cultivation areas dominated by peat soils, research was conducted during the dry season of 2001 on land belonging to the community of Pelalawan village, Pelalawan district, Riau province, Indonesia. The research showed that burning did not affect all peat areas equally. No peat was burned on a fibric site, while burning on a hemic site varied in depth from 6.0 cm to 12.6 cm, and on a sapric site from 15.4 cm to 31.9 cm. Further, on the fibric site only phosphorus increased significantly following burning, while on the hemic only the base saturation increased; on the sapric site, however, both base saturation and phosphorus increased compared to the condition before burning. These data show that if fire is continues to be used for land preparation in peat areas, peat becomes critically endangered.  相似文献   

6.
基于MODIS影像估算中国大陆区域草地火污染物时空格局   总被引:1,自引:1,他引:0  
草地火是草地生态系统重要干扰因子,对草地生态系统结构和功能有重要影响.草地火释放的大量烟气和颗粒物对大气环境、生态系统和人类健康有重要影响.本研究基于2001—2017年中国大陆区域MODIS-MCD64A1数据,结合生物质密度,估算各区域草地火燃烧生物量.并运用排放因子法,估算17年间中国大陆区域草地火排放污染物总量.研究结果表明,中国大陆地区草地生物质密度存在差异,由东向西逐渐递减.草地火时空分布不均衡且存在明显季节性差异,主要集中在3月和9月.中国大陆地区2001—2017年草地火次数、火面积和燃烧总量分别是1.63×10~5次、6.12×10~6 hm~2和23.86 Mt,排放CO_2、CO、CH_4、SO_2、NMVOC、NO_x、PM_(2.5)、BC、OC和TC总量分别为37.27 Mt、1.31 Mt、43.30 kt、11.05 kt、287.74 kt、79.60 kt、155.82 kt、9.25 kt、64.95 kt和75.54 kt.此外,各污染物在时间和空间上不均衡,在东北、华北、华中和西南区域呈增加趋势,华东和西北区域呈降低趋势,华南区域呈显著降低趋势.本研究揭示了中国大陆地区草地火释放污染物的时空变化,为深入揭示草地火对区域环境影响提供数据支持.  相似文献   

7.
Fires are critical elements in the Earth System, linking climate, humans, and vegetation. With 200–500 Mha burnt annually, fire disturbs a greater area over a wider variety of biomes than any other natural disturbance. Fire ignition, propagation, and impacts depend on the interactions among climate, vegetation structure, and land use on local to regional scales. Therefore, fires and their effects on terrestrial ecosystems are highly sensitive to global change. Fires can cause dramatic changes in the structure and functioning of ecosystems. They have significant impacts on the atmosphere and biogeochemical cycles. By contributing significantly to greenhouse gas (e.g., with the release of 1.7–4.1 Pg of carbon per year) and aerosol emissions, and modifying surface properties, they affect not only vegetation but also climate. Fires also modify the provision of a variety of ecosystem services such as carbon sequestration, soil fertility, grazing value, biodiversity, and tourism, and can hence trigger land use change. Fires must therefore be included in global and regional assessments of vulnerability to global change. Fundamental understanding of vulnerability of land systems to fire is required to advise management and policy. Assessing regional vulnerabilities resulting from biophysical and human consequences of changed fire regimes under global change scenarios requires an integrated approach. Here we present a generic conceptual framework for such integrated, multidisciplinary studies. The framework is structured around three interacting (partially nested) subsystems whose contribute to vulnerability. The first subsystem describes the controls on fire regimes (exposure). A first feedback subsystem links fire regimes to atmospheric and climate dynamics within the Earth System (sensitivity), while the second feedback subsystem links changes in fire regimes to changes in the provision of ecological services and to their consequences for human systems (adaptability). We then briefly illustrate how the framework can be applied to two regional cases with contrasting ecological and human context: boreal forests of northern America and African savannahs.  相似文献   

8.
火灾对周围的环境造成水污染、大气污染、有毒气体的污染等,严重影响我们生活环境。人们对环境保护的意识在逐年提高,对于火灾造成的环境污染也开始努力控制。  相似文献   

9.
Charcoal fragments in forest soils give evidence of prehistoric and historic natural and anthropogenic wildfires in the equatorial rainforests and in seasonal monsoon forests of continental and insular South Asia. Conditions favourable for the occurrence of historic and contemporary rainforest fires are associated with droughts, especially during dry spells caused by the El Niño–Southern Oscillation (ENSO) event. Historic land-use fires and wildfires can be reconstructed from a number of narrative reports, including documents that reveal drought and famine. In the eastern part of Borneo prehistoric and historic records of coal fires reveal a unique natural source of wildfires. Starting with modern transmigration programs and systematic conversion of primary and secondary vegetation, including peat-swamp ecosystems, into farmland and industrial plantations, the use of fire as a land-clearing tool escalated in the 1990s. During droughts land-clearing fires additionally contribute to wildfires. A detailed study of the ecological consequences of the episode of land-use fires and wildfires of 1982–1983 was conducted on an area of 2.7 million ha of dipterocarp rainforest in East Kalimantan. The results show that dipterocarps are highly susceptible to fire and are replaced by pioneers and fire-tolerant species that occupy the disturbed sites or survive the immediate fire effects. Smoke from forest conversion burning caused considerable environmental problems, reducing visibility and affecting human health and security. Emissions from vegetation burning influence chemistry and functioning of the global atmosphere. The situation is different in those parts of mainland and insular Southeast Asia that are characterized by seasonal climate. Through long-term influence of climate variability, fire influence, and anthropogenic pressure the vegetation is better adapted to extrinsic stresses. During the 15 years between the extreme ENSO events and fire episodes of 1982–1983 and 1997–1998 the national and international communities have been alerted and prepared to respond to the escalating fire situation in Indonesia. The response to the onset of the 1997–1998 fire and smoke episode, however, was absolutely inadequate and erratic. Meanwhile a whole continent – the maritime continent of Southeast Asia – has been degraded by excessive fire application for more than 20 years.  相似文献   

10.
This paper describes the development and analysis of a dataset covering bushfire related life loss in Australia over the past 110 years (1901–2011). Over this time period 260 bushfires have been associated with a total of 825 known civilian and firefighter fatalities. This database was developed to provide an evidence base from which an Australian national fire danger rating system can be developed and has benefits in formalising our understanding of community exposure to bushfire. The database includes detail of the spatial, temporal and localised context in which the fatalities occurred. This paper presents the analysis of 674 civilian fatalities. The analysis has focused on characterising the relationship between fatal exposure location, weather conditions (wind speed, temperature, relative humidity and drought indices), proximity to fuel, activities and decision making leading up to the death.The analysis demonstrates that civilian fatalities were dominated by several iconic bushfires that have occurred under very severe weather conditions. The fatalities from Australia's 10 worst bushfire days accounted for 64% of all civilian fatalities. Over 50% of all fatalities occurred on days where the McArthur Forest Fire Danger Index (FFDI) exceeded 100 (the current threshold for declaring a day as ‘catastrophic’) proximal to the fatality.The dominant location category was open air representing 58% of all fatalities followed by 28% in structures, and 8% in vehicles (6% are unknown). For bushfires occurring under weather conditions exceeding an FFDI value of 100, fatalities within structures represented over 60% of all fatalities. These were associated with people dying while attempting to shelter mainly in their place of residence. Of the fatalities that occurred inside a structure in a location that was specifically known, 41% occurred in rooms with reduced visibility to the outside conditions. Over 78% of all fatalities occurred within 30 m of the forest.  相似文献   

11.
以某原油库为例,较为系统地介绍油库火灾爆炸事故的风险防范措施,并采用美国道化学公司的火灾爆炸危险指数法确定所采取的风险防范措施在降低火灾爆炸事故危险性的作用,同时举例说明应急预案的主要内容,为其他油库项目的风险管理提供一定的参考,具有一定的实际应用价值。  相似文献   

12.
13.
现代城市地震次生火灾发生概率大,扑救难度大,极易造成大量的人员伤亡以及财产损失。大量的统计数据表明,震后火灾的诱因、时空分布及消亡因素有着一定的规律性。本文在详细分析城市地震次生火灾发生的原因、火灾时空分布及危害特点的基础上,针对应急处置对策和长远处置对策等方面提出了新的观点,可供消防部队处置此类灾害时参考。  相似文献   

14.
During the last two decades Indonesia has experienced immense forest and land fires. Often these fires are associated with extended drought and widespread use of fire to clear previously logged forest and other degraded land in preparation for oil palm, rubber, or pulpwood plantations. There are many reasons for the use of fire in land clearing activities, but probably the most important one is economics. There is still acceptance that fire is the cheapest, fastest, and most effective land clearing method with the added benefit of providing nutrients from ash residues. This paper provides a review of existing information on the financial costs and benefits of using fire for land clearing in agriculture and forestry plantations as compared with zero-burning techniques. The findings indicate that the economic advantage of fire use varies widely and depends on many factors, such as soil fertility, vegetation density, labour cost, equipment and training costs, and the costs of fire management. For large-scale land clearing, the financial analysis of the costs and benefits of fire versus zero-burning shows that when applied to low-volume vegetation, zero-burning methods are not more expensive than burning – and may actually be more cost effective in the long term. This is the case for clearing oil palm or rubber plantations for replanting, low secondary vegetation, and heavily logged-over forest. Under high-volume forest conditions, burning remains less expensive because it is more difficult, time consuming, and costly to dispose of high volumes of piled wood mechanically.  相似文献   

15.
Problem of wildfires has not been resolved anywhere in the world. Mere increase of technical power does not lead to desirable results. Forests of developed countries burn as actively as those in Africa or in Russia. The main reasons of wildfire problem are as follows: (1) Constant wandering of dry seasons over the planet causing outbreaks of wildfires. (2) Unpredicted self-development of ordinary wildfires into awful fire disasters. (3) Difficulties in delivery and use of heavy machines on hardly accessible territories. (4) Absence of a perfect technique for economic evaluation of how effectively the wildfire control system works. (5) Absence of the system of payments encouraging wildfire fighters. To solve the problem of wildfires in Russia it is necessary to: (1) Create the Russian wildfire behaviour and fire effects prediction system on the basis of the developed classification of vegetation fuels and methods of their mapping as well as maximum utilization of forest inventory information and Geographic Information System (GIS). (2) Elaborate a technique of proper wildfire monitoring including estimation of vegetation damage. (3) Improve daily rating of regional fire danger. (4) Improve fire-preventive arrangement of the territory covered by vegetation, the main goal being creation of favourable conditions for active fire management. (5) Choose the main direction in elaboration of fire-fighting means and methods taking into account their universality, simplicity, reliability, etc. (6) Elaborate an improved technique for estimation of economic effectiveness of the wildfire control system. (7) Develop international cooperation of scientists and professionals in fire management.  相似文献   

16.
中国亚热带地区2000-2014年林火排放颗粒物时空动态变化   总被引:1,自引:0,他引:1  
林火是森林生态系统重要干扰因子并对大气环境和人类健康有显著影响.该研究基于2000-2014年中国亚热带地区卫星火点数据,结合林业统计年鉴,估算各区域林火燃烧生物量,运用排放因子法,估算15年间中国亚热带地区林火排放颗粒物总量.研究结果表明,亚热带地区林火存在季节性差异,福建、广东、广西、湖南和江西林火主要集中在春、秋两季;贵州和云南林火主要集中在春季;浙江林火集中在春、夏两季.亚热带地区森林可燃物总燃烧量为333.92 Mt,污染物PM2.5、OC、EC和TC总量分别为:698.33、338.18、40.04和378.22 kt,此外,各污染物排放在时间和空间上不均衡,各污染物排放量多集中在云南南部和东南部,湖南、贵州和广东交汇处,广东东南部和福建中部等区域;PM2.5、OC、EC和TC在浙江、云南、贵州、湖南和江西呈显著增长趋势.林火释放PM2.5与工业粉尘的排放比变化趋势总体呈上升趋势,说明森林火灾导致的颗粒物排放对大气环境影响力呈逐年增长趋势.该文通过对中国亚热带地区林火释放污染物的时空变化研究,为深入揭示林火对区域环境的影响提供数据支持.  相似文献   

17.
2015年强厄尔尼诺引起东南亚干旱少雨与活跃火加剧,但目前有关活跃火时空特征、发生类型与强度及其对人口—社会经济影响仍分析不足。利用美国国家航空航天局火灾信息资源管理系统(FIRMS)VIIRS V1活跃火位置矢量产品,通过月际、地形、土地覆被类型等GIS分析确定东南亚主要国家活跃火主要类型,并评价各国活跃火对人口分布的影响范围与国别差异。结果表明:(1)东南亚2015年活跃火发生频次达81.40×105次,中南半岛与马来群岛各占69.60%与30.40%,分别集中发生在2-4月与8-10月,各国活跃火频次与发生时间差异很大。(2)中南半岛五国活跃火地形差异明显,缅甸和越南活跃火集中分布于25 m以下;老挝(85~105 m、140~200 m)、泰国(5~15 m、70~110 m)和柬埔寨(5~15 m、70~110 m)活跃火随海拔呈双峰特征;马来群岛国家(印度尼西亚、马来西亚与菲律宾)活跃火集中分布于60 m以下的平原地带;且东南亚35%以上的活跃火均集中分布5~15°的斜坡。(3)东南亚森林、农田活跃火发生率为76%,其中森林活跃火发生率由柬埔寨的52.00%到老挝的74.27%不等,农田活跃火由老挝的13.18%到泰国的42.68%不等。(4)综合活跃火发生月份、海拔、坡度与覆被特征,可从山区刀耕火种农业与平原秸秆焚烧界定东南亚主要国家活跃火发生类型。(5)东南亚活跃火随人口密度增加呈先增后减至平稳变化的趋势,且多集中于人口稀少的乡村和原始森林,其中缅甸、泰国、越南三国有10%以上的活跃火发生在人口密度为72~91人/km2的区域,而马来西亚、老挝、柬埔寨、印度尼西亚30%以上的活跃火集中发生于人口密度在20人/km2以下的区域。  相似文献   

18.
The author uses his own data gleaned from over 10 years of commercial forestry insurance across the world to propose that despite a low intrinsic fire risk across most of Southeast Asia, especially Indonesia, commercial fire losses are unacceptably high, and could be reduced substantially within the current financial legal and political framework within which forestry companies operate. Opening with a statement about the dearth of forest fire loss data in the commercial sector, it is observed that the consequent inability of general insurers to estimate the rate of fire loss leads to very low insurance participation in forestry within Indonesia. A summary is then provided of the financial and environmental benefits of insurance participation in commercial forestry were this situation to be changed. A short discussion on risk perceptions is introduced to make the point that without reliable commercial forest fire loss data, risk perceptions of fire exposure in Southeast Asia by the financial sector, including insurers, is a barrier to risk transfer and investment. While real fire risk and perceived fire risk for Indonesia seem at present to be in agreement, the paper challenges that this should the case. Comparisons are made with different parts of the world with the knowledge that, in commercial terms, plantations in the low latitudes behave similarly everywhere in terms of fire causes, fire propagation factors, and characteristics of plantation or managed mixed forest fires. A review of the fire sizes within commercial forests is a good indicator of the efficiency of fire management strategies, and profiles from a high fire risk territory and Indonesia are compared. Using commercial and unidentified data the author then demonstrates that commercial growers in Indonesia have a high annual rate of forest fire loss and may also have a significant catastrophe fire exposure. This ‘cat’ exposure is far greater than for equivalent plantations in clearly higher fire risk environments. These conclusions are and should be discussed with forestry companies to change attitude and investment levels. Practical points for improved plantation fire management are made along with comments about the resources required. A parallel discussion then reviews fire risk assessment and management by the insurers to prevent their own ‘forest fire’ losses if they are to get further involved with the provision of Indonesian commercial forest risk transfer. The explanation of how insurers price risk within a portfolio helps identify the specific data needed for a proper risk management strategy to be developed.  相似文献   

19.
大城市区域霾与雾的区别和灰霾天气预警信号发布   总被引:39,自引:6,他引:33  
由于经济规模的迅速扩大和城市化进程的加快,都市霾现象或者是灰霾天气日趋严重,霾与雾的区分成为一个非常现实,又迫切需要解决的问题。通常在平面时已达到饱和的水汽压,对相当于球面的云雾滴来讲就是未饱和的,那样云雾滴就会蒸发;在水汽条件不变时,云雾滴由于蒸发而变小,导致它的平衡水汽压升高,则更易蒸发掉。在不饱和大气中小于数微米的云雾滴必然蒸发,而且伴随着蒸发云雾滴尺度会进一步变小,导致曲率越来越大,蒸发速率越来越快。过去错误认为凝结核可以在低相对湿度情况下产生凝结生成雾滴的观点,是忽视了粒子曲率作用的结果,将实验室大颗粒(常常达毫米量级)的吸湿性特征,延用至次微米粒子造成的。降温是达到饱和形成雾滴的即重要又主要的物理过程,云雾是低温下饱和气块的可见标志。在云雾中必然存在凝结或凝华过程,因而必然伴随着潜热释放,这就使云雾内的温度高于环境,在云雾内必然盛行微弱的上升气流,不可能是下沉气流,这些宏观过程在霾层内是不存在的,因而成为识别霾与雾的重要的宏观动力条件。在对历史资料进行统计时,在排除降水、吹雪、雪暴、沙尘暴、扬沙、浮尘、烟幕、等等视程障碍现象的情况下,通过调试相对湿度,使得雾与轻雾反映自然的年际与年代际气候波动,而霾反映由于人类活动而引起的趋势性变化,其限值大体在90%左右,与美国和英国讨论霾影响能见度的长期变化趋势的研究中使用的相对湿度限值相同,他们都去除了相对湿度>90%的资料,只研究了相对湿度<90%时的能见度变化趋势。进行相对湿度订正才能确保资料的高质量。近年来由于人类活动大气气溶胶污染日趋严重,1980年代以来大幅增加的霾日,绝大部分是由于人类活动影响的气溶胶细粒子污染造成的。依据本文和以前的研究,给出了霾与雾区分的概念模型,霾与雾观测的标准,和灰霾天气预警信号发布的标准。  相似文献   

20.
深圳地区灰霾分布特征及预警、预报方法探讨   总被引:4,自引:2,他引:2  
基于深圳市国家气候观象台1953—2010年的灰霾UV统计资料、气象要素值、灰霾出现前期及同期的地面和850hPa的天气形势资料和自动站的能见度统计资料以及深圳市环境监测站的1980—2010年污染物浓度资料,对深圳市灰霾天气的出现规律及影响要素特征进行了概括分析.在此基础上运用逐步回归的方法,筛选出影响灰霾主要因子,建立未来1—3d的能见度预报方程.同时通过对灰霾出现前天气形势的分析和归纳,建立灰霾潜势预报的思路.并进一步对灰霾天气的典型因子进行权重分级.最后集成以上3种预测方法,归纳出灰霾预警方案,形成灰霾预警预报模型.利用实测结果对模型检验,结果表明:该模型具有一定的准确率和可靠性,对灰霾预测具有较好的应用价值,为灰霾防治和预警系统的建立提供科学依据.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号