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1.
本文简要阐述了水灭火法灭火原理与系统组成,提出通过建立永久性贮水池促进水灭火法将成为我国林火扑救重要手段的发展设想。  相似文献   
2.
《草业科学》2012,43(4)
主要介绍了矿井火灾决策系统的组成及应用。矿井火灾决策系统能大大节省灾变时期的反应时间,为企业在第一时间采取果断措施尽可能消除或减少火灾损失争取宝贵的时间,对于矿井火灾的防治具有重要的意义。  相似文献   
3.
Encroachment of Great Plains grasslands by fire-sensitive woody plants is a large-scale, regional process that fragments grassland landscapes. Using prairie grouse (Tympanuchus spp.) of conservation concern, we apply hierarchy theory to demonstrate how regional processes constrain lower-level processes and reduce the success of local management. For example, fire and grazing management may be locally important to conservation, but the application of fire and grazing disturbances rarely cause irreversible fragmentation of grasslands in the Great Plains. These disturbance processes cause short-term alterations in vegetation conditions that can be positive or negative, but from a long-term perspective fire maintains large tracts of continuous rangelands by limiting woody plant encroachment. Conservation efforts for prairie grouse should be focused on landscape processes that contribute to landscape fragmentation, such as increased dominance of trees or conversion to other land uses. In fact, reliance on local management (e.g., maintaining vegetation structure) to alter prairie grouse vital rates is less important to grouse population persistence given contemporary landscape level changes. Changing grass height, litter depth, or increasing the cover of forbs may impact a few remaining prairie-chickens, but it will not create useable space at a scale relevant to the historic conditions that existed before land conversion and fire suppression.  相似文献   
4.
本文从阐述河南县草原防火工作现状和存在的主要问题入手,针对性的提出了今后草原防火的意见建议。  相似文献   
5.
Juniper and piñon coniferous woodlands have increased 2- to 10-fold in nine ecoregions spanning the Intermountain Region of the western United States. Control of piñon-juniper woodlands by mechanical treatments and prescribed fire are commonly applied to recover sagebrush steppe rangelands. Recently, the Sage Grouse Initiative has made conifer removal a major part of its program to reestablish sagebrush habitat for sage grouse (Centrocercus urophasianus) and other species. We analyzed data sets from previous and ongoing studies across the Great Basin characterizing cover response of perennial and annual forbs that are consumed by sage grouse to mechanical, prescribed fire, and low-disturbance fuel reduction treatments. There were 11 sites in western juniper (Juniperus occidentalis Hook.) woodlands, 3 sites in singleleaf piñon (Pinus monophylla Torr. & Frém.) and Utah juniper (Juniperus osteosperma [Torr.] Little), 2 sites in Utah juniper, and 2 sites in Utah juniper and Colorado piñon (Pinus edulis Engelm). Western juniper sites were located in mountain big sagebrush (A. tridentata ssp. vaseyana) steppe associations, and the other woodlands were located in Wyoming big sagebrush (A. tridentata ssp. wyomingensis) associations. Site potential appears to be a major determinant for increasing perennial forbs consumed by sage grouse following conifer control. The cover response of perennial forbs, whether increasing (1.5- to 6-fold) or exhibiting no change, was similar regardless of conifer treatment. Annual forbs favored by sage grouse benefitted most from prescribed fire treatments with smaller increases following mechanical and fuel reduction treatments. Though forb abundance may not consistently be enhanced, mechanical and fuel reduction conifer treatments remain good preventative measures, especially in phase 1 and 2 woodlands, which, at minimum, maintain forbs on the landscape. In addition, these two conifer control measures, in the short term, are superior to prescribed fire for maintaining the essential habitat characteristics of sagebrush steppe for sage grouse.  相似文献   
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7.
李媛  程积民  于鲁宁  陈奥 《草业科学》2011,28(6):1052-1058
摘要:以云雾山典型草原本氏针茅(Stipa bungeana)群落为对象,研究了火烧后2年、10年和未烧草地群落的物种重要值、群落平均高度、盖度、密度、地上生物量、多样性指数及枯落物积累量的变化。结果表明,1)3个样地中,本氏针茅和白颖苔草(Carex rigesoens)是共优势种;火烧后2年和未烧地,铁杆蒿(Artemisia sacrorum)成为次优势种,而火烧后10年,赖草(Leymus secalinus)成为次优势种。2)火烧后2年地,群落的平均高度显著减小(P<0.05);火烧后10年地,群落的平均盖度显著减小(P<0.05);火烧后2年和火烧后10年地,群落的平均密度显著增加(P<0.05)。3)火烧后,群落的地上生物量、多样性指数、丰富度指数、均匀度指数差异均不显著(P>0.05)。4)枯落物积累量变化表现为:未烧地>火烧后10年地>火烧后2年地,差异显著(P<0.05)。  相似文献   
8.
Fire products have been widely identified as germination cues for a number of species from both fire-prone and fire-free ecosystems. However, there is uncertainty about the effects of fire products on seed germination of semi-arid rangeland species. We examined the germination of seven dominant species from Central Zagros rangelands in the semi-arid region of Iran under various heat shock (60, 80 and 120 °C), aerosol smoke, ash and control treatments. Our findings showed that fire products could enhance, inhibit or not affect the seed germination of rangeland species in this area. The germination percentage of Astragalus adscendens increased following 60 °C heat treatment in comparison with the control. The germination of Astragalus verus, Bromus tectorum, B. tomentellus and Phlomis olivieri were increased significantly using smoke treatment (P<0.0001). The seed germination of B. tomentellus and B. tectorum was promoted by ash treatment, whereas the other species exhibited no response or were inhibited by fire products. In addition, smoke treatment shortened the overall germination time of B. tectorum. These findings suggest that fire products affect the germination of several species and can serve as potential tools for understanding the vegetation dynamics and restoration of disturbed semi-arid rangelands.  相似文献   
9.
草原火研究综述   总被引:3,自引:0,他引:3  
火作为重要的生态因子与我们的生活息息相关。国内外已对草原火展开了一定研究,本文讨论了草原火的研究成果,从影响因素、生态影响、时空分布格局、草原火的管理、遥感监控、预警和风险评价7个方面进行深入的探讨。一方面可为相关决策部门提供有力的科学依据,进而保证对草原火规范管理、草原生态环境平衡;另一方面,可为草原火发生发展过程,及其对相关区域乃至未来全球气候变化的影响研究提供依据,进而为当前全球变化研究做出贡献。由于目前在研究领域的局限性和研究时间间断性出现的问题,最后分析了草原火的研究趋势,并对火生态因子对全球气候变化影响和火灾预测模型有待深入的研究难点和发展趋势进行了展望。  相似文献   
10.
在结缕草萌动前对结缕草草地进行火烧处理,研究生长季内不同月份火烧对结缕草草地杂草的控制效果。结果表明:整个生长季内火烧对结缕草草地杂草株数、植物量(地上,干重)均有较好的防控效果,平均防控效果分别为23.97%、39.90%;株数防控效果最好为5月份,为40.95%,植物量防控效果最好为10月份,为65.74%;火烧对结缕草草地杂草的防控效果在春季主要表现在防控杂草的数量(株数),在秋季主要表现在防控杂草的重量(地上植物量)。  相似文献   
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