Target Tailored Forest Damage Inventory (TFDI) - Damage by bark beetle in Västernorrland 2011

Inventories of forest damage are carried out within the Swedish University of Agricultural Sciences (SLU) Forests programme. An annual monitoring of the most important sources of forest damage is carried out by the Swedish National Forest inventory (NFI). Although the Swedish NFI is an objective and uniform inventory of forest damage in Swedish forests at national and regional scales, less common or less widespread occurrences of forests pests and pathogens are difficult to survey solely through large-scale monitoring programmes. There is a need for complementary inventories to facilitate timely delivery of relevant information.

Thus Target-tailored forest damage inventories (TFDI) aiming at providing data for operational decisions making at local level, and linked to specific damage events were introduced. TFDI’s are developed to give rapid response to requested information of specific damage outbreaks. The TFDI’s are carried out in limited and concentrated samples, with flexible but robust methods and design. The data collected in the TFDI shall also be of such quality that it can be useful in research.
During 2011 TFDI carried out a sample inventory of the volume Norway spruce (Picea abies) damage by bark beetles, Four-eyed spruce bark beetle (Polygrapus poligraphus) and/or European spruce bark beetle (Ips typographus) in older spruce forest in the county of Västernorrland. The purpose of the inventory was to estimate the volume Norway spruce damage by the given bark beetles, but also to highlight geographical distribution and the appearance of the damage in different forest sites.

The inventory was stratified by an objective sample of the National Forest Inventory al permanent sample plots in the county of Västernorrland. Included plots within the sample was older thinning forest and final felling mature forest consisting of at least 7/10 spruce and a lesser proportion of forest with lesser share of spruce or younger thinning forest. The radii of sample plots use for the damage inventory was 25 m. Diameter at breast height was measured on damage trees. Furthermore specie of bark beetle and age of damage was recorded. In total 97 plots and 236 trees was measured.

Some assessed and used variables
At sample plot level
Plot area measured
Occurrence of new attack of Four eyed spruce bark beetle
Occurrence of new attack of European spruce bark beetle
Occurrence of older damage caused by the bark beetles
The proportion of spruce damage by bark beetles sample plot radii 10 m
The proportion of spruce damage by bark beetles sample plot radii 25 m
The proportion of spruce at the sample plot

At tree level
Is the tree dead or alive?
Diameter at breast height
Which specie of bark beetle has attacked the tree?
Which season did the damage occur?
Distance to tree edge
Tree height Tree volume

See the document "Data_description" for more detailed information. As additional documentation, field instructions for the inventories are also provided.

瑞典农业科学大学（Swedish University of Agricultural Sciences, SLU）森林项目组开展森林损害清查工作。瑞典国家森林清查（National Forest Inventory, NFI）会对主要森林损害源开展年度监测。尽管瑞典NFI是在国家和区域尺度上开展的客观统一的森林损害清查，但针对较罕见或分布范围较窄的森林有害生物与病原物，仅依靠大规模监测项目难以实现全面调查，因此亟需补充清查工作以及时获取相关有效信息。
为此，针对特定损害事件、旨在为地方层面运营决策提供数据支持的目标定制化森林损害清查（Target-tailored forest damage inventories, TFDI）应运而生。TFDI可针对特定损害暴发事件快速响应并提供所需信息，采用有限集中的抽样方案，搭配灵活且稳健的方法与设计框架。TFDI所采集的数据需具备足够质量，同时可服务于科研需求。
2011年，TFDI在西诺尔兰郡（Västernorrland）的老龄云杉林内，针对由四眼小蠹（Four-eyed spruce bark beetle, Polygrapus poligraphus）和/或欧洲云杉树皮甲虫（European spruce bark beetle, Ips typographus）引发的挪威云杉（Picea abies）损害开展抽样清查。本次清查的目标不仅是估算上述树皮甲虫造成的挪威云杉损害蓄积量，同时还需明确损害的地理分布特征，以及不同林分的损害表现形式。
本次清查以西诺尔兰郡国家森林清查的永久性固定样地为客观抽样基础。入选样地包括至少7/10占比为云杉的老龄间伐林、最终采伐成熟林，以及云杉占比较低的林分或幼龄间伐林。本次损害清查所用样地半径为25米。对受害木测定胸径，同时记录蛀干害虫种类与损害发生时长。本次清查共完成97个样地的调查，测定了236株林木。
部分评估与使用的变量如下：
1. 样地水平变量：
样地面积测定值
四眼小蠹新侵害发生情况
欧洲云杉树皮甲虫新侵害发生情况
上述树皮甲虫引发的旧损害发生情况
样地半径10米范围内的云杉损害占比
样地半径25米范围内的云杉损害占比
样地内云杉占比
2. 单木水平变量：
林木存活状态（存活/死亡）
胸径
侵害该林木的树皮甲虫种类
损害发生季节
林木距林缘距离
树高
林木蓄积量
详细信息请参阅"Data_description"文档，本次清查的野外操作指南也作为补充文档一并提供。