Precautions against forest fires,a significant element in the prevention and reduction of natural disasters in China,are very important to the development of public emergency systems,as well as to the safety of forest...Precautions against forest fires,a significant element in the prevention and reduction of natural disasters in China,are very important to the development of public emergency systems,as well as to the safety of forest resources,ecology,people’s lives and properties.The USA has extensive experience in forest fire management,which has been widely accepted and used by other countries.The precautions taken by China and the USA to prevent forest fires have been compared in a great number of previous studies.However,most of the studies have focused merely on fire extinguishing technologies and management methods;they have lacked a comparative study on the legal aspects of management.This paper will consider five distinct aspects related to forest fire management between China and the USA and will analyze the similarities and differences as well as study other features to facilitate work related to precautions against forest fires in China.展开更多
North and west China has abundant coal resources, however, such resources make these regions prone to serious mine fire disasters. Although the copious sand and fly ash resources found in these areas can be used as fi...North and west China has abundant coal resources, however, such resources make these regions prone to serious mine fire disasters. Although the copious sand and fly ash resources found in these areas can be used as fire-fighting materials, conventional grouting is expensive because of water shortage and loess particles. A new compound material(i.e., a sand-suspended colloid), which comprises a mineral inorganic gel and an organic polymer, is developed in the current study to improve the quality of sand injection and reduce water wastage when grouting. The new material can steadily suspend the sand, through the addition of a small amount of colloid yielding steady sand-suspended slurry. The process of producing the slurry is convenient and quick, overcoming the shortage of sand-suspending thickeners which need heat and are difficult to produce. The space work model based on the theory of the double-electric layer is established to study the suspended mechanism of the solid particles in the sand-suspended colloid.The dispersion effect of the sand-suspended colloid is demonstrated by the incorporation of the electrostatic effect by the double-electric layer and the steric hindrance effect on the sand particles, ensuring the stability of the colloid system and the steady suspension of sand particles in the sand-suspended colloid.Mechanical analysis indicates that the sand is suspended steadily under the condition that the rock sand particles stress on the lower part of the fluid is less than the yield stress of the colloid. Finally, the fireprevention technology of sand suspension was applied and tested in the Daliuta Coal Mine, achieving successful results.展开更多
Effective landscape-scale fuel management strategies are essential for reducing wildfire risk in Mediterranean fire-prone areas.In this study,the minimum travel time(MTT)fire-spread algorithm as implemented in FlamMap...Effective landscape-scale fuel management strategies are essential for reducing wildfire risk in Mediterranean fire-prone areas.In this study,the minimum travel time(MTT)fire-spread algorithm as implemented in FlamMap was applied to assess the potential of alternative fuel treatments for lowering wildfire losses in a 5,740-ha study area in eastern Sardinia,Italy.Twenty-seven wildfires at 10-m resolution were simulated considering three wind speeds(15,18,and 21 km h-1)to compare fuel treatments:no treatment(NT),irrigated agroforestry areas with shrub clearing(T1),prescribed fire in eucalyptus stands(T2),and irrigated grasslands(T3).The simulations replicated a recent large wildfire that occurred in the study area(Orrìwildfire,2019)and considered the weather and fuel moisture conditions associated with this event.The average wildfire exposure outputs(burned area,probability of burning,conditional flame length,potential crown fire occurrence,and surfaces withflame lengths above 2.5 m)decreased after fuel treatments,compared to no treatment.T1 was the most effective strategy in mitigating wildfire hazards and provided the most significant performance for several wildfire exposure indicators.Treating only 0.5%of the study area(~30 ha)resulted in a decrease in all wildfire exposure metrics to~10%within the study area.In addition,the total surface characterized by high flame length(average>2.5 m)was the lowest in the T1 treatment.This study can help land and fire managers optimize fuel treatment opportunities and wildfire risk mitigation strategies in Mediterranean areas.展开更多
基金supported by the State Bureau of Forestry 948 project(2015-4-35)the Fundamental Research Funds for the Central Universities(2572015CA10)National Natural Science Foundation of China(31400551)
文摘Precautions against forest fires,a significant element in the prevention and reduction of natural disasters in China,are very important to the development of public emergency systems,as well as to the safety of forest resources,ecology,people’s lives and properties.The USA has extensive experience in forest fire management,which has been widely accepted and used by other countries.The precautions taken by China and the USA to prevent forest fires have been compared in a great number of previous studies.However,most of the studies have focused merely on fire extinguishing technologies and management methods;they have lacked a comparative study on the legal aspects of management.This paper will consider five distinct aspects related to forest fire management between China and the USA and will analyze the similarities and differences as well as study other features to facilitate work related to precautions against forest fires in China.
基金support of the research funds provided by the National Natural Science Foundation of China (Nos. 51304071, 51304073)the Open Projects of State Key Laboratory of Coal Resources and Safe Mining, China University of Mining & Technology of China (No. 12KF02)
文摘North and west China has abundant coal resources, however, such resources make these regions prone to serious mine fire disasters. Although the copious sand and fly ash resources found in these areas can be used as fire-fighting materials, conventional grouting is expensive because of water shortage and loess particles. A new compound material(i.e., a sand-suspended colloid), which comprises a mineral inorganic gel and an organic polymer, is developed in the current study to improve the quality of sand injection and reduce water wastage when grouting. The new material can steadily suspend the sand, through the addition of a small amount of colloid yielding steady sand-suspended slurry. The process of producing the slurry is convenient and quick, overcoming the shortage of sand-suspending thickeners which need heat and are difficult to produce. The space work model based on the theory of the double-electric layer is established to study the suspended mechanism of the solid particles in the sand-suspended colloid.The dispersion effect of the sand-suspended colloid is demonstrated by the incorporation of the electrostatic effect by the double-electric layer and the steric hindrance effect on the sand particles, ensuring the stability of the colloid system and the steady suspension of sand particles in the sand-suspended colloid.Mechanical analysis indicates that the sand is suspended steadily under the condition that the rock sand particles stress on the lower part of the fluid is less than the yield stress of the colloid. Finally, the fireprevention technology of sand suspension was applied and tested in the Daliuta Coal Mine, achieving successful results.
基金funded by"MED-Star"(Grant No.E88H19000120007)“Med-Foreste”(grant no.B85I1900010007)+5 种基金“Med-Coopfi re”(Grant No.B81I1900010007)projectssupported by the European Union under the cross-border Programma Italia-Francia Marittimo 2014–2020the“FOE2019-Climate Change:risk mitigation for sustainable development”(Ministerial Decree no.856/19)projectfunded by the Italian Ministry of EducationUniversity and Research(MIUR)co-financed by the University of Sassari,Fondo di Ateneo per la Ricerca Scientifica(FAR)2020。
文摘Effective landscape-scale fuel management strategies are essential for reducing wildfire risk in Mediterranean fire-prone areas.In this study,the minimum travel time(MTT)fire-spread algorithm as implemented in FlamMap was applied to assess the potential of alternative fuel treatments for lowering wildfire losses in a 5,740-ha study area in eastern Sardinia,Italy.Twenty-seven wildfires at 10-m resolution were simulated considering three wind speeds(15,18,and 21 km h-1)to compare fuel treatments:no treatment(NT),irrigated agroforestry areas with shrub clearing(T1),prescribed fire in eucalyptus stands(T2),and irrigated grasslands(T3).The simulations replicated a recent large wildfire that occurred in the study area(Orrìwildfire,2019)and considered the weather and fuel moisture conditions associated with this event.The average wildfire exposure outputs(burned area,probability of burning,conditional flame length,potential crown fire occurrence,and surfaces withflame lengths above 2.5 m)decreased after fuel treatments,compared to no treatment.T1 was the most effective strategy in mitigating wildfire hazards and provided the most significant performance for several wildfire exposure indicators.Treating only 0.5%of the study area(~30 ha)resulted in a decrease in all wildfire exposure metrics to~10%within the study area.In addition,the total surface characterized by high flame length(average>2.5 m)was the lowest in the T1 treatment.This study can help land and fire managers optimize fuel treatment opportunities and wildfire risk mitigation strategies in Mediterranean areas.
