国际木材交易是大生意，值得一些2260亿美元在2015年。不幸的是，这笔交易的很大一部分是非法的.

2014年，联合国预防犯罪和刑事司法委员会宣布非法伐木为“serious crime,” meriting the same level of attention as crimes such as drug trafficking. Crimes range from lone operators stealing trees from protected forests to sophisticated transnational schemes involving mislabeling of shipments, avoidance of taxes, and corrupt government officials and companies.

But just as illegal loggers are becoming more sophisticated in their thievery, so, too, are the technologies to catch these culprits. Advances in everything from chemistry to computing are helping authorities identify illegal timber and arrest its traders.

What Is This Wood, and Where Did It Come From?

确定不同类型的木材是与非法伐木作斗争的当局的关键障碍。除了专家以外的大多数人，各种木材看起来都一样，这使得从合法收获的物种中了解一个受保护的物种变得棘手。即使您知道一个样品是柚木，也很难说出它来自哪个国家。伴随木材运输的文书工作可能会提供此信息，但是这些论文经常在许多原籍国伪造。

尽管还有更多可用的东西，但四种有希望的方法论已经发布了识别木材物种的成功，或两者兼而有之。

Wood anatomyfocuses on the physical properties of wood, where an investigator analyzes – either on a macro or micro scale - the anatomical differences between species of trees and compares the differences to a reference sample or database. At the macro level, a simple magnifying glass can be used; for more precise identification, the investigator might turn to a high-resolution microscope. The technique has been在巴西部署了很大的作用。

这些努力正在不断发展，包括计算机援助。这 ”xylotron由美国森林服务部开发的，正在通过在微观木质幻灯片的图像上使用类似于人类面部识别软件的算法来锻造木材解剖结构的新边界。该方法中的力量来自系统比较数千个图像以基于微妙的诊断特征来识别物种的能力，这些特征很难用人的眼睛识别。

基于DNA的分析has great potential as a method for accurately identifying both species and origin of timber specimens, and even individual trees.

DNA-based methods do, however, face some remaining technical challenges. First, it is still relatively difficult to reliably extract useable DNA from wood products that have been mixed with other species, or have been heat-treated, exposed to glues, or otherwise processed. Second, the diagnostic power of the genetic characteristics, or “markers,” a researcher has identified varies among different kinds of trees. The Quercus (oak) genus, for example, is characterized by a high level of hybridization between species, reducing the reliability of genetic markers to help determine species and origin of specimens.

识别木材是与犯罪驱动的森林砍伐的第一步。wri/flickr的照片
识别木材是与犯罪驱动的森林砍伐的第一步。wri/flickr的照片

Several technologies rely on analysis of the chemical properties within the wood sample:

稳定的同位素analysis is a method where investigators analyze isotopic ratios, a sort of atomic signature which trees absorb from the surrounding water, air and soil. These ratios are indicative of specific regions on the earth, allowing a researcher to identify the origin of a wood specimen. While the granularity varies, innovative developments employing chemometric analyses and the addition of rare earth and trace elements may soon lead researchers to finer-scale origin identification.

DART-TOFMS(实时直接分析（飞行时间）质谱法）是一种应用加热至450°C的氦离子流以挥发在木材样品表面和表面上的化学物质的方法，提供了完整的化学轮廓。该工具的功能来自于几乎没有或没有样品制备的快速分析样品的快速能力。

In some cases, a combination of these techniques may be the most effective approach. For example, an investigator could use DART-TOFMS to identify the chemical signature of a specific tress species and couple that data with stable isotope information providing the isotopic signature of the tree’s origin.

雨林犯罪现场调查人员添加工具

尽管这些技术中的每一个都预示着巨大的希望，但仍存在障碍。参考数据库是当务之急。执法人员还必须采用新工具，购买技术和培训人员的使用将需要足够的资金。

These difficulties aren’t insurmountable. In fact, before fingerprinting became a ubiquitous tool for crimefighters, it faced similar challenges. With support and investment to develop and field-test these technologies further, the use of these “rainforest CSI” tools could become just as commonplace—and effective in fighting crime--as fingerprinting.

Much of this information came out of discussions at a recent workshop, Development and Scaling of Innovative Technologies for Wood Identification.在这里了解更多.