The Development and Application of Automatic Measurement System for Forest Canopy Closure

doi:10.13466/j.cnki.lyzygl.2020.02.025

Abstract

Abstract:

The requirement of forestry information modernization is to obtain the forest canopy closure automatically and quickly.In order to calculate canopy closure quickly and cheaply,an automatic measurement system was designed.The system was developed by raspberry pie and algorithm programming,which had the function of field data collection and remote information management.Canopy closure value was extracted using ring-cutting and binarization image processing technology.It avoided the complex fisheye lens distortion correction process.The system provides a visual interface,integrated raspberry pie,fisheye lens,battery and wireless router and so on,which makes it easy to operate.This study took Jinsiwan Forest Park,Sanming city as the study case.Canopy closure values determined using the automatic measurement system and look-up method,respectively.It showed that R² was 0.699 between the automatic measurement system and look-up method.The system is helpful for the rapid measurement of canopy closure and provides reference for the application and promotion.

Key words: ring-cutting, binarization, canopy closure, fisheye lens, internet of things

CLC Number:

LIN Lili, HAO Zhenbang, YANG Liuqing, GAO Yangchi, LIU Yanfen, YU Kunyong, LIU Jian. The Development and Application of Automatic Measurement System for Forest Canopy Closure[J]. FOREST RESOURCES WANAGEMENT, 2020, (2): 167-172.

Figures/Tables 9

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样地	平均胸径/cm	平均树高/m	密度/(株/hm²)
1	18.27	14.27	1067
2	18.39	13.55	1022
3	23.90	17.17	585
4	23.51	20.40	649
5	14.79	14.49	975
6	26.75	19.11	602
7	17.89	15.48	799
8	21.64	20.76	698

样地号	系统估测	抬头望法	样地号	系统估测	抬头望法	样地号	系统估测	抬头望法
1-1	0.81	0.80	4-1	0.78	0.77	7-1	0.77	0.75
1-2	0.80	0.79	4-2	0.79	0.80	7-2	0.73	0.70
1-3	0.75	0.76	4-3	0.77	0.75	7-3	0.73	0.71
1-4	0.78	0.77	4-4	0.78	0.76	7-4	0.78	0.74
1-5	0.85	0.85	4-5	0.80	0.77	7-5	0.79	0.76
2-1	0.81	0.80	5-1	0.80	0.78	8-1	0.76	0.78
2-2	0.80	0.77	5-2	0.76	0.77	8-2	0.76	0.78
2-3	0.80	0.77	5-3	0.80	0.78	8-3	0.77	0.79
2-4	0.79	0.80	5-4	0.75	0.74	8-4	0.76	0.75
2-5	0.78	0.79	5-5	0.75	0.73	8-5	0.80	0.80
3-1	0.79	0.80	6-1	0.76	0.75
3-2	0.77	0.77	6-2	0.77	0.78
3-3	0.81	0.80	6-3	0.80	0.78
3-4	0.77	0.79	6-4	0.79	0.81
3-5	0.79	0.80	6-5	0.71	0.68