森林野火 & 农村社区

提高复原力:森林、野火和社区

和许多国家一样，美国的森林大火.S. are getting worse and overly dense forests are part of the problem. A healthy demand for wood products gives landowners a financial incentive for forest thinning and other landscape restoration efforts that reduce the fire risk. 特别是, mass timber creates an opportunity for large structural elements to be manufactured from relatively small-diameter trees and those affected by insects, 疾病, 和火. 它还为加强农村经济提供了一条途径. 大量的木材产品需要复杂的制造工艺, 规划, 换句话说，还有其他植物的位置, well-paying jobs in communities that often need an economic boost. So, building urban wood buildings has a very real connection to the health of our natural environment and the success of rural towns.

过度茂密的森林

在美国.S.在美国，森林约占陆地面积的三分之一. 在过去的100年里, the makeup of forested landscapes in the West has changed from patchwork patterns with natural firebreaks to forests with much greater density. 加上气候变化，包括变暖, drier and windier weather—these overly dense forests create prime conditions for increasingly large and catastrophic wildfires.¹

For more information on the impacts of forest density , watch the Ted Talk, Why wildfires have gotten worse—and what we can do about it by Paul Hessburg of the USDA 林务局 and University of Washington/Oregon State University.

北美的森林正在枯竭吗?

美国的森林面积.S. has been stable for more than 100 years, despite a huge increase in population. 据保守估计，美国经济增长将放缓.S. was home to 76 million people in 1900 and there are more than 330 million people today. 然而,, 如下图所示, we have about the same amount of forested land as we did at the turn of the last century. 

In addition to a stable amount of forested land overall, the U.S. has experienced an increase in the volume of trees on its 林地—also known as “working forests.” These are the lands available for timber harvesting and do not include national parks or wilderness areas. 增加意味着树木存量的净增长, 而减少则意味着树木的整体损失. The data considers all losses, including natural mortality, wildfire, and harvesting. 自1953年以来, 这些土地上的木材量增加了60%, 如下图所示.² 每年只有不到2%的森林被砍伐.³

森林生长vs. 搬迁是另一项措施. 下图显示了美国的增长和减少.S. 林地. 可以再次看到，增长速度超过了移除速度.

指定木材会导致森林砍伐吗?

让我们考虑一下它的定义. Deforestation is the permanent conversion of forest land to non-forest land uses. Worldwide, agricultural expansion is the main driver of deforestation, but here in the U.S., the rate of deforestation has been virtually zero for decades.⁴ In the photo below, you can see an area that was clearcut and is in the early stages of regeneration. The vegetation in the foreground likely represents 10 or so years of growth following harvest.

这并不是说我们对未来没有担忧. 野火, 吃水, 昆虫和疾病的爆发, 以及转换林地进行开发, agriculture and other uses are all real issues—which strong markets for wood are helping to address.

在美国.S.在中国，私有林地占林地总面积的58%. 超过1000万人, 家庭土地所有者, 部落占总数的38%, 而公司拥有剩下的20%.³  而美国的森林所有权.S. is fairly evenly split between private and public ownership, 私有土地占所有采伐木材的89%.²

What motivates these groups and individuals to keep their lands forested? 经济价值是一个主要因素. If landowners don’t derive enough value from their forests, 他们更有可能将其转化为其他用途. 同样的, the more financial incentive there is to practice sustainable forestry, the more private landowners will invest in practices aimed at long-term forest health. 例如, thinning overly dense areas helps improve the health of remaining trees by reducing competition for water and nutrients. Healthier trees are able to cope better with drought conditions, have a better survival rate from insect and 疾病 outbreaks, 并且从小型或中等强度的火灾中恢复得更好.

同时专注于公共森林, the USDA 林务局 is helping to build strong markets for wood products across the U.S.，这对公共和私人土地都有好处. 这是美国的一个优先重点.S. 林务局 Wood Innovations Grant Program is mass timber, which can utilize smaller-diameter trees and trees affected by insects, 疾病与火, 同时为森林社区带来高薪工作. It is a means to support long-term sustainable forest management, 减少温室气体排放, and put rural America at the forefront of an emerging industry.⁵

For more information on forest ownership, management, and trends across the U.S.，看看这些资源:

U.S. 美国农业部(USDA).S. 林务局. (2017). 美国森林资源，2017. 

国会研究处. (2021). 焦点:美国.S. 森林所有权和管理.

Center for International Trade in Forest Products (CINTRAFOR), 自然资源空间信息学小组(NRSIG). (2023). 美国大量木材消费的增加.S. 可持续的木材供应.

认为木材. (2015). 木材使用对北美森林的影响.

¹ Hessburg P. 美国农业部U.S. 森林服务, 华盛顿大学-俄勒冈州立大学. (2020). 21世纪野火和气候的变化^st 世纪西方 U.S.

² 美国农业部U.S. 林务局. (2019). 美国森林资源，2017.

³ 森林工作倡议.

⁴ 世界自然基金会. 森林砍伐:对人类和自然的威胁.

⁵ 美国农业部U.S. 林务局. 木材创新计划.