可燃物

Shrubs are found in most regions and include some low-growing trees, such as scrub oaks.  灌木的分布广泛，其中也包含长势低矮的树木，比如矮栎。

May burn very actively, or may slow the spread of fire depending on type of shrub and time of year.  这类可燃物是形成活跃的燃烧，还是会减缓火势蔓延，主要取决于灌木的类型和在一年中所处的时间段。

The shrub type is highly influenced by drought conditions.  灌木类型受干旱条件的影响很大。

When the shrub type is receptive, it has the potential to spread fire quickly.  如果植物是亲水的，有可能形成快速的火势蔓延。

Commonly found in the plains regions and high deserts, grass-shrub is a mixture of fine grass and shrubs.常见于平原和沙漠高原，是细草和灌木的混合体。

Fire behavior in this type combines the features of the grass fuel type and the shrub fuel type.灌草火灾行为兼具草原火灾和灌木火灾的特点。

Fires may spread rapidly with wind, but more slowly than a grass fuel type.在风的作用下火势蔓延快，但比单纯的草原火慢很多。

Shrubs add intensity to the fire and may produce spotting, but fires are less intense than in the Shrub type.灌木的加入会增强火势，但比单纯灌木火势要弱，同时可能会产生飞火点。

Where it may be safe to move in the grass type immediately after fire passes, it may not be safe in this type because of longer-burning shrubs .由于灌木燃烧时间较长，所以不会形成像草原上火焰过后立刻形成的安全区。

Timber-understory refers to a canopy of trees with other plants (such as shrubs and small trees) growing below them. 林下植物是指树木树冠下生长的植物（比如灌木和小树）。

Fires in this type combine the features of the timber litter type and the shrub type, moving faster than fires in timber litter, but burning longer than fires in shrubs. 此类型可燃物的火灾兼具枯枝落叶层和灌木火的特点。比枯枝落叶层的火势蔓延速度快，燃烧时间长于灌木火。

Fires in this fuel type can move very quickly and with intensity, especially when understory trees/shrubs act as a ladder for fire to climb into the upper canopy.当火势借助林下树木和灌木的“阶梯作用”爬上上面的树冠，燃烧会转变为非常快速的猛烈燃烧。

The amount of fuel present expressed quantitatively in terms of weight of fuel per unit area.火灾荷载：给定面积内燃料的数量

This may be available fuel (consumable fuel) or total fuel and is usually dry weight. 质量采用燃料的干重（燃料干燥之后的重量）

The loading of fuels in any given area does not necessarily mean that fire will burn with great intensity.  火灾荷载的大小并不能完全代表火势的强弱。

Chemical content refers to the presence of substances in the fuel such as: 

燃料中的化学成分指的是：

Fuels with high amounts of these substances can contribute to rapid rates of spread and high fire intensities.  如果可燃物中此类化学成分含量高，将有助于形成快速蔓延并猛烈燃烧的火势。

Fuel arrangement is divided into two primary categories: 可燃物的分布分为两个方面：

Fuel Continuity is the degree or extent of continuous or uninterrupted distribution of fuel particles in a fuel bed thus affecting a fire‘s ability to sustain combustion and spread. This applies to aerial fuels as well as surface fuels. 燃料连续性描述的是可燃物分布连续性或不间断性的程度，这会影响可燃物持续燃烧的能力和火势蔓延的速度与范围。

Horizontal, continuous fuels are closely packed and in direct contact with one another.  水平方向上连续的可燃物紧密地堆积在一起，彼此直接接触。

Two main categories: 根据水平连续性可以分为两类：

Uniform, continuous fuels describe areas containing a network of connected fuels, allowing a continuous path for fire to spread. 均匀连续性分布会在一定区域内形成可燃物彼此相连的网络，能够为火势蔓延提供连续性路径。

The fuels affect the rate of ignition and spread potential by allowing fire to move steadily from one piece of fuel to the next.这种分布能够使火灾在不同可燃物间稳定的传播，从而影响引火和蔓延速度。

Objects blocking the continuous distribution of fuels include:阻隔可燃物连续分布的物体包括：

Vertical arrangement of fuels is broken into four categories:  从竖向分布角度可以将可燃物分为四类：

All combustible materials below the surface litter, including duff, tree, or shrub roots, punky wood, peat, and sawdust, which normally support a glowing combustion without flame. 地面枯枝落叶层下的可燃物，包括腐殖层、树木和灌木的根系、腐朽的木材、泥炭、木屑，通常会形成无焰燃烧。

Ground fuels do not spread fire quickly, but they can pose problems for containing fires.底层可燃物的火势蔓延速度较慢，但也会对火灾的控制造成问题。

Ground fuels burn below the surface of the ground, out of sight, making it difficult to detect.  They can burn for extended periods–weeks, and, in some cases, years.底层可燃物的燃烧发生在地面以下，因为难以观测到，所以很难探测。它们的燃烧会持续数周，甚至一些情况下可以持续数年。

Smoldering ground fuels can burn underneath firelines and cause fires to spread out of containment lines. 底层可燃物的阴燃会发生在防火线以下，导致火灾穿过控制线。

Fuels lying on or near the surface of the ground, consisting of leaf, and needle litter, dead branch material, downed logs, bark, tree cones, and low stature living plants. 表面可燃物是指在地面以上或地面附近的可燃物，包括树叶、针叶层、干枯的树枝、倒下的木材、树皮、低矮植物。

Includes most of the material we think about as fuel for wildland fires and are the primary carriers of fire once ignition has occurred.  表面可燃物包括大部分我们所能想到的野外火灾可燃物，也是火灾发生后主要促使火势蔓延的可燃物。

The primary fuel to remove to break the fire triangle. 也是灭火过程中首先要移除的可燃物。

Moisture content is the single most important factor in determining how well a fuel will ignite and burn.  含水量是决定燃料引燃和燃烧难易程度的一个非常重要的因素。

Two categories:  含有的水分分为两类：

In general, at the height of the growing season, live fuel moistures will be at their highest and will progressively decrease throughout the fire season, whereas dead fuel moistures can fluctuate frequently throughout the fire season based on immediate precipitation, relative humidity, and sunlight. 一般来说，在生长季节的高峰期，活着的可燃物湿度最高，在整个易发生火险的季节会逐渐减少，而枯死的可燃物湿度在整个易发生火险的季节会根据降水、相对湿度和日照的情况而频繁波动。

Due to variations in characteristics, as well as size, different fuels located in the same area will have varying moisture levels.  由于自身生长特性、尺寸的差异，在相同区域生长的不同植物，其含水量也会不同。

The drier a fuel is, the more likely it is to catch fire and the hotter it will burn.燃料越干，着火的可能性越大，燃烧的温度也越高。