摘要
茶叶是一种高附加值的经济作物,是我国南方山区乡村振兴的主要抓手。由于毁林种茶等破坏行为,导致森林资源破坏并引发水土流失等生态环境问题。快速准确获取茶园的空间分布对于政府监管和茶叶产业的规划发展至关重要。由于研究区天气多阴雨,茶园分布较为分散,与森林等植被光谱较为接近等原因,导致基于卫星影像提取茶园挑战性较大。为了摸清英德市的茶园空间分布,系统分析了中高分辨率的多光谱Sentinel-2影像数据,结合多时序多特征信息在茶园提取中的应用潜力。以英德市全境为研究区,选用2019年—2021年的9期Sentinel-2影像数据,详细分析了茶树生长的物候特征,进一步探究了茶园和其他地类在多时序中的特征变化,采用Relief算法对所有特征进行重要性排序。根据特征排序结果,选取特征权重值加权90%的特征因子,即7个植被指数特征和2个纹理特征,通过不同的组合排序构建了9种茶园分类场景,采用RF算法对所有分类场景进行精度评价,选取最佳分类场景,进一步探讨了RF分类算法和SVM分类算法对茶园提取的可行性。结果表明:(1)在进行英德市茶园提取时,2月和10月是采用多时相构造茶园多特征的最佳组合,可能因2月茶树处于萌芽期长出部分嫩绿的新叶易于和森林植被区分且在10月前后由于茶园进行了修剪其特征也较明显,因此两时相特征融合易于区分茶园。(2)RF分类方法与SVM分类方法相比,后者的精度较高,其总体精度达到91.56%,Kappa系数为0.89,生产者精度和用户精度分别为80.22%和84.56%。该研究为快速高效获取英德市茶园空间分布信息提供了一种高效的方法,同时为政府在进行茶叶产业规划、管理提供了数据支持。
Tea is a high value-added economic crop with extremely high economic value.It is the main starting point for rural revitalization in mountainous areas of China.However,due to destructive behaviors such as deforestation and planting tea,forest resources are destroyed,and ecological and environmental problems such as soil erosion are caused.Acquiring the spatial distribution of tea plantations quickly and accurately is very important for government supervision and the planning and development of the tea industry.However,due to the rainy weather in the study area and the scattered distribution of tea plantations,which are close to the spectrum of vegetation such as forests,the extraction based on satellite imagery has become a problem.Tea plantations are challenging.In order to find out the spatial distribution of tea plantations in Yingde,this paper systematically analyzes the application potential of medium and high-resolution multispectral Sentinel-2 image data combined with multi-time-series and multi-feature information in tea garden extraction.Taking the whole territory of Yingde as the research area,this paper selects 9 phases of Sentinel-2 image data from 2019 to 2021 to analyze the phenological characteristics of tea tree growth in detail and further explore the characteristics changes of tea plantations and other land types in multiple time series,using the Relief algorithm to sort the importance of all features.According to the result of feature sorting,the feature factors weighted by 90%of the feature weight value are selected,namely 7 vegetation index features and 2 texture features,and 9 kinds of tea garden classification scenes are constructed through different combination rankings,and the RF algorithm is used to evaluate the accuracy of all classification scenes.To select the best classification scene and further discuss the feasibility of the RF classification algorithm and SVM classification algorithm for tea garden extraction.The results show that:(1)When extracting tea plantations in Yingde,February and October are the best combinations to construct multiple characteristics of tea plantations using multi-temporal phases.(2)Compared with the SVM classification method,the RF classification method has high accuracy.Its overall accuracy reaches 91.56%,the Kappa coefficient is 0.89,and the producer accuracy and user accuracy are 80.22%and 84.56%,respectively.This study provides an efficient method for quickly and efficiently obtaining the spatial distribution information of tea plantations in Yingde and provides data support for the government to plan and manage the tea industry.
作者
陈盼盼
任艳敏
赵春江
李存军
刘玉
CHEN Pan-pan;REN Yan-min;ZHAO Chun-jiang;LI Cun-jun;LIU Yu(Research Center of Information Technology,Beijing Academy of Agriculture and Forestry Sciences,Beijing 100097,China)
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2024年第4期1136-1143,共8页
Spectroscopy and Spectral Analysis
基金
国家重点研发计划项目(2020YFD1100202)
北京市农林科学院2022年科研创新平台项目(PT2022-24)
北京市农林科学院博士后基金项目(2021-ZZ-002)资助。
