Identifying Tree Species in a Warm-Temperate Deciduous Forest by Combining Multi-Rotor and Fixed-Wing Unmanned Aerial Vehicles

Fixed-wing unmanned aerial vehicles (UAVs) and multi-rotor UAVs are widely utilized in large-area (>1 km<sup>2</sup>) environmental monitoring and small-area (<1 km<sup>2</sup>) fine vegetation surveys, respectively, having different characteristics in terms of flight c...

Full description

Bibliographic Details
Main Authors: Weibo Shi, Shaoqiang Wang, Huanyin Yue, Dongliang Wang, Huping Ye, Leigang Sun, Jia Sun, Jianli Liu, Zhuoying Deng, Yuanyi Rao, Zuoran Hu, Xiyong Sun
Format: Article
Language:English
Published: MDPI AG 2023-05-01
Series:Drones
Subjects:
Online Access:https://www.mdpi.com/2504-446X/7/6/353
_version_ 1797595288074977280
author Weibo Shi
Shaoqiang Wang
Huanyin Yue
Dongliang Wang
Huping Ye
Leigang Sun
Jia Sun
Jianli Liu
Zhuoying Deng
Yuanyi Rao
Zuoran Hu
Xiyong Sun
author_facet Weibo Shi
Shaoqiang Wang
Huanyin Yue
Dongliang Wang
Huping Ye
Leigang Sun
Jia Sun
Jianli Liu
Zhuoying Deng
Yuanyi Rao
Zuoran Hu
Xiyong Sun
author_sort Weibo Shi
collection DOAJ
description Fixed-wing unmanned aerial vehicles (UAVs) and multi-rotor UAVs are widely utilized in large-area (>1 km<sup>2</sup>) environmental monitoring and small-area (<1 km<sup>2</sup>) fine vegetation surveys, respectively, having different characteristics in terms of flight cost, operational efficiency, and landing and take-off methods. However, large-area fine mapping in complex forest environments is still a challenge in UAV remote sensing. Here, we developed a method that combines a multi-rotor UAV and a fixed-wing UAV to solve this challenge at a low cost. Firstly, we acquired small-scale, multi-season ultra-high-resolution red-green-blue (RGB) images and large-area RGB images by a multi-rotor UAV and a fixed-wing UAV, respectively. Secondly, we combined the reference data of visual interpretation with the multi-rotor UAV images to construct a semantic segmentation model and used the model to expand the reference data. Finally, we classified fixed-wing UAV images using the large-area reference data combined with the semantic segmentation model and discuss the effects of different sizes. Our results show that combining multi-rotor and fixed-wing UAV imagery provides an accurate prediction of tree species. The model for fixed-wing images had an average F1 of 92.93%, with 92.00% for <i>Quercus wutaishanica</i> and 93.86% for <i>Juglans mandshurica</i>. The accuracy of the semantic segmentation model that uses a larger size shows a slight improvement, and the model has a greater impact on the accuracy of <i>Quercus liaotungensis</i>. The new method exploits the complementary characteristics of multi-rotor and fixed-wing UAVs to achieve fine mapping of large areas in complex environments. These results also highlight the potential of exploiting this synergy between multi-rotor UAVs and fixed-wing UAVs.
first_indexed 2024-03-11T02:34:07Z
format Article
id doaj.art-da3ff6236a3c4a59be03b74f11028a4a
institution Directory Open Access Journal
issn 2504-446X
language English
last_indexed 2024-03-11T02:34:07Z
publishDate 2023-05-01
publisher MDPI AG
record_format Article
series Drones
spelling doaj.art-da3ff6236a3c4a59be03b74f11028a4a2023-11-18T10:03:54ZengMDPI AGDrones2504-446X2023-05-017635310.3390/drones7060353Identifying Tree Species in a Warm-Temperate Deciduous Forest by Combining Multi-Rotor and Fixed-Wing Unmanned Aerial VehiclesWeibo Shi0Shaoqiang Wang1Huanyin Yue2Dongliang Wang3Huping Ye4Leigang Sun5Jia Sun6Jianli Liu7Zhuoying Deng8Yuanyi Rao9Zuoran Hu10Xiyong Sun11Hubei Key Laboratory of Regional Ecology and Environment Change, School of Geography and Information Engineering, Chinese University of Geosciences, Wuhan 430074, ChinaHubei Key Laboratory of Regional Ecology and Environment Change, School of Geography and Information Engineering, Chinese University of Geosciences, Wuhan 430074, ChinaState Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, ChinaState Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, ChinaState Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, ChinaInstitute of Geographical Sciences, Hebei Academy of Sciences, Shijiazhuang 050011, ChinaHubei Key Laboratory of Regional Ecology and Environment Change, School of Geography and Information Engineering, Chinese University of Geosciences, Wuhan 430074, ChinaChina TOPRS Technology Co., Ltd., Beijing 100039, ChinaHubei Key Laboratory of Regional Ecology and Environment Change, School of Geography and Information Engineering, Chinese University of Geosciences, Wuhan 430074, ChinaHubei Key Laboratory of Regional Ecology and Environment Change, School of Geography and Information Engineering, Chinese University of Geosciences, Wuhan 430074, ChinaHubei Key Laboratory of Regional Ecology and Environment Change, School of Geography and Information Engineering, Chinese University of Geosciences, Wuhan 430074, ChinaHubei Key Laboratory of Regional Ecology and Environment Change, School of Geography and Information Engineering, Chinese University of Geosciences, Wuhan 430074, ChinaFixed-wing unmanned aerial vehicles (UAVs) and multi-rotor UAVs are widely utilized in large-area (>1 km<sup>2</sup>) environmental monitoring and small-area (<1 km<sup>2</sup>) fine vegetation surveys, respectively, having different characteristics in terms of flight cost, operational efficiency, and landing and take-off methods. However, large-area fine mapping in complex forest environments is still a challenge in UAV remote sensing. Here, we developed a method that combines a multi-rotor UAV and a fixed-wing UAV to solve this challenge at a low cost. Firstly, we acquired small-scale, multi-season ultra-high-resolution red-green-blue (RGB) images and large-area RGB images by a multi-rotor UAV and a fixed-wing UAV, respectively. Secondly, we combined the reference data of visual interpretation with the multi-rotor UAV images to construct a semantic segmentation model and used the model to expand the reference data. Finally, we classified fixed-wing UAV images using the large-area reference data combined with the semantic segmentation model and discuss the effects of different sizes. Our results show that combining multi-rotor and fixed-wing UAV imagery provides an accurate prediction of tree species. The model for fixed-wing images had an average F1 of 92.93%, with 92.00% for <i>Quercus wutaishanica</i> and 93.86% for <i>Juglans mandshurica</i>. The accuracy of the semantic segmentation model that uses a larger size shows a slight improvement, and the model has a greater impact on the accuracy of <i>Quercus liaotungensis</i>. The new method exploits the complementary characteristics of multi-rotor and fixed-wing UAVs to achieve fine mapping of large areas in complex environments. These results also highlight the potential of exploiting this synergy between multi-rotor UAVs and fixed-wing UAVs.https://www.mdpi.com/2504-446X/7/6/353fixed-wing UAVsmulti-rotor UAVssemantic segmentation methodtree species classificationforest inventory
spellingShingle Weibo Shi
Shaoqiang Wang
Huanyin Yue
Dongliang Wang
Huping Ye
Leigang Sun
Jia Sun
Jianli Liu
Zhuoying Deng
Yuanyi Rao
Zuoran Hu
Xiyong Sun
Identifying Tree Species in a Warm-Temperate Deciduous Forest by Combining Multi-Rotor and Fixed-Wing Unmanned Aerial Vehicles
Drones
fixed-wing UAVs
multi-rotor UAVs
semantic segmentation method
tree species classification
forest inventory
title Identifying Tree Species in a Warm-Temperate Deciduous Forest by Combining Multi-Rotor and Fixed-Wing Unmanned Aerial Vehicles
title_full Identifying Tree Species in a Warm-Temperate Deciduous Forest by Combining Multi-Rotor and Fixed-Wing Unmanned Aerial Vehicles
title_fullStr Identifying Tree Species in a Warm-Temperate Deciduous Forest by Combining Multi-Rotor and Fixed-Wing Unmanned Aerial Vehicles
title_full_unstemmed Identifying Tree Species in a Warm-Temperate Deciduous Forest by Combining Multi-Rotor and Fixed-Wing Unmanned Aerial Vehicles
title_short Identifying Tree Species in a Warm-Temperate Deciduous Forest by Combining Multi-Rotor and Fixed-Wing Unmanned Aerial Vehicles
title_sort identifying tree species in a warm temperate deciduous forest by combining multi rotor and fixed wing unmanned aerial vehicles
topic fixed-wing UAVs
multi-rotor UAVs
semantic segmentation method
tree species classification
forest inventory
url https://www.mdpi.com/2504-446X/7/6/353
work_keys_str_mv AT weiboshi identifyingtreespeciesinawarmtemperatedeciduousforestbycombiningmultirotorandfixedwingunmannedaerialvehicles
AT shaoqiangwang identifyingtreespeciesinawarmtemperatedeciduousforestbycombiningmultirotorandfixedwingunmannedaerialvehicles
AT huanyinyue identifyingtreespeciesinawarmtemperatedeciduousforestbycombiningmultirotorandfixedwingunmannedaerialvehicles
AT dongliangwang identifyingtreespeciesinawarmtemperatedeciduousforestbycombiningmultirotorandfixedwingunmannedaerialvehicles
AT hupingye identifyingtreespeciesinawarmtemperatedeciduousforestbycombiningmultirotorandfixedwingunmannedaerialvehicles
AT leigangsun identifyingtreespeciesinawarmtemperatedeciduousforestbycombiningmultirotorandfixedwingunmannedaerialvehicles
AT jiasun identifyingtreespeciesinawarmtemperatedeciduousforestbycombiningmultirotorandfixedwingunmannedaerialvehicles
AT jianliliu identifyingtreespeciesinawarmtemperatedeciduousforestbycombiningmultirotorandfixedwingunmannedaerialvehicles
AT zhuoyingdeng identifyingtreespeciesinawarmtemperatedeciduousforestbycombiningmultirotorandfixedwingunmannedaerialvehicles
AT yuanyirao identifyingtreespeciesinawarmtemperatedeciduousforestbycombiningmultirotorandfixedwingunmannedaerialvehicles
AT zuoranhu identifyingtreespeciesinawarmtemperatedeciduousforestbycombiningmultirotorandfixedwingunmannedaerialvehicles
AT xiyongsun identifyingtreespeciesinawarmtemperatedeciduousforestbycombiningmultirotorandfixedwingunmannedaerialvehicles