摘要:近年来，随着气候变化和人类活动的加剧，全球森林面积持续减少、质量下降，生态环境事件频发，森林健康的问题受到前所未有的关注，已经成为生态文明战略的重要组成部分。我国森林资源持续增长，但同时也面临一些问题，如：造林结构单一、林分质量不高、生态稳定性弱等，如何系统准确评价其森林健康状况仍然是当前难点。相对于传统地面调查方法，遥感技术具有实时获取、重复监测以及多时空尺度等优势，并且随着高分遥感和人工智能等技术的飞速发展，大幅提高了解决森林健康评价难题的能力。为系统评估新型遥感技术应用于评价森林健康的潜力，本文在文献分析基础上，指出了现有路径和方法，具体包括：�?）通过文献计量学方法分析并明确了森林健康评价的4大核心内容（活力、组织结构、抵抗力和恢复力）和4大关键问题（树种分类、林木活力、林业有害生物、干旱胁迫）。（2）从不同尺度（单木−林分−生态系统−景观）、不同平台（近地面遥感−航空遥感−卫星遥感）和不同传感器（包括RGB相机、多/高光谱相机、激光雷达、热红外相机、微波雷达和叶绿素荧光扫描仪�?个角度，系统梳理现有遥感技术的优缺点。（3）围�?个关键问题，阐述近年来应用遥感技术评价森林健康的路径和方法。进一步，本文指出了包括多数据源融合分析、森林健康监测网络与近地面遥感、森林健康大数据应用在内的挑战与机遇，以期为我国森林资源智慧管理提供参考、�p style="line-height: 12px;">

关键诌�
• 森林健康/
• 遥感技�?/a> /
• 传感�?/a> /
• VOR体系/
• 林业有害生物

Abstract:In recent years, with the aggravation of climate change and human activities, the global forest area continues to reduce, forest quality keeps declining, and the ecological and environmental events occur frequently. Thus, forest health issues have received unprecedented attention, and have become an important part of the ecological civilization strategy. China’s forest resources continue to grow, but it also faces some problems, such as single afforestation structure, low stand quality and weak ecological stability. How to evaluate forest health systematically and accurately is still a difficult problem. Compared with the traditional ground survey methods, remote sensing technology has the advantages of macroscopic, timeliness and economic efficiency. With the rapid development of high-resolution remote sensing and artificial intelligence technology, it is possible to overcome the problem of forest health assessment. In order to systematically evaluate the potential of new remote sensing technology, this paper points out the existing paths and methods on the basis of literature analysis, including: (1) through bibliometric analysis, four core contents of forest health assessment (vitality, organizational structure, resistance and resilience) and four key issues (tree species classification, forest vitality, forest pests, drought threat) were identified. (2) Systematically interpreting the advantages and disadvantages of existing remote sensing technologies from three angles, namely, different scales (single tree stand ecosystem landscape), different platforms (near ground remote sensing, aerial remote sensing satellite remote sensing) and different sensors (including RGB cameras, multi/hyperspectral cameras, lidar, thermal infrared cameras, microwave radars and chlorophyll fluorescence scanners). (3) Focusing on four key issues, this paper expounds the application path and method of remote sensing technology to evaluate forest health in recent years. Furthermore, this paper points out the challenges and opportunities, including multi-source fusion analysis, forest health monitoring network and near ground remote sensing, forest health big data application, in order to provide reference for the intelligent management of forest resources in China.

Key words:
• forest health/
• remote sensing/
• sensor/
• VOR system/
• forestry pest

�?nbsp; 1森林健康评价指标体系一级结构、准则层的词云图和词频分枏�/p>

Figure 1.Word cloud and frequency analysis of primary structure and criterion layer of forest health assessment indicator system

下载: 全尺寸图牆�/a> 幻灯牆�/a>

�?nbsp; 2多尺度、多平台遥感技术评价森林健康概念图

Figure 2.Concept map of multi-scale, multi-platform remote sensing assessment of forest health

下载: 全尺寸图牆�/a> 幻灯牆�/a>

�?nbsp; 1不同传感器在森林健康评价中的技术优势和主要评价内容

Table 1.Advantages and application of different sensors in forest health assessment

传感�?br/>Sensor	技术优劾�br/>Technical advantage	主要不足 Main shortcomings	特征参量 Feature parameter	评价内容 Assessment content
RGB高分相机 RGB high-resolution camera	低成本、高空间分辨玆�br/>Low cost, high spatial resolution	成像质量受光照条件影响大、光谱信息有陏�br/> Image quality is influenced by illumination conditions, limited spectral information	RGB图像、纹� RGB image, texture	普适性好，一般作为遥感底图或摄影测量数据 Widely used as RS base map or photogrammetric data
多光谱成像仪 Multispectral sensor	几个波段的反射率 Reflectance of several bands	异物同谱、同物异谱问题使数据解译困难 Difficult data interpretation due to synonyms spectrum	多光谱图像、多通道反射� Multispectral image, multi-channel reflectance	树种分类、主要生化组分、物候、胁� Tree species classification, main biochemical components, phenology, stress
高光谱成像仪 Hyperspectral sensor	上百个窄波段的反射率 Reflectance of hundreds of narrow bands	观测条件严格、数据量大、分析难度大 Strict observation condition and difficult data analysis	图谱立方� Hyperspectral cube	树种分类、多种生化组分、光合作用、物候、早期胁� Tree species classification, photosynthesis, various biochemical components, phenology, early stress
热红外相朹�br/>Thermal camera	全天候、穿透性、精细温�?br/>All weather, penetrating, fine temperature difference	温度变化易受周围环境影响 Temperature variation is easily affected by the surrounding environment	方向亮度温度、热红外图像 Directional brightness temperature, thermal infrared image	森林火灾、森林干旱、光合作用、早期胁�?br/> Forest fire, drought, photosynthesis, early stress
激光雷辽�br/>LiDAR	穿透性、精细的地形和森林三维信� Penetrating, fine terrain and 3D forest information	缺少光谱、纹理信� Lack of spectral and texture information	点云廓线、波彡�br/>Point cloud profile, waveform	地形、位置、生物量、蓄积量、冠层结构、叶面积指数 Topography, location, biomass, volume, canopy structure, LAI
微波雷达 Microwave radar	全天候，一定穿透性，可达地下 All weather, limited penetrating, reaching underground	斑点噪声大、受地形影响 严重 Speckle noise and seriously affected by terrain	后向散射、干涉系数、极化雷达图� Backscattering, interference coefficient, polarimetric radar image	地形、生物量、蓄积量、水分、土� Topography, biomass, volume, moisture, soil
叶绿素荧光扫描仪 Chlorophyll fluorescence scanner	获取日光诱导的叶绿素信息 Capturing chlorophyll information induced by sunlight	受大气影响大、时空连续性有� Affected by atmosphere, limited space-time continuity	荧光参数、光化学效率 Fluorescence parameters, photochemical efficiency	初级生产力、碳循环、物候、早期胁� Primary productivity, carbon cycle, phenology, early stress

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