ABSTRACT

Unmanned Aerial Vehicle (UAV) based remote sensing is one of the modern techniques for crop management, which has been used in this study for biomass and Nitrogen (N) level estimations for Stevia rebaudiana, a medicinal crop used as an alternative to sugar as a natural sweetener. Different levels of nitrogen treatments were given to S. rebaudiana and the crops were harvested for biomass estimation. Mica sense Altum multispectral sensor on board was used for acquiring the image data of the crop. The linear regression model was used to examine the best vegetation index using K-fold cross validation approach. Excess Green Index (ExG) was identified as best vegetation index for biomass estimation (R² = 0.7; RMSE =23.77 g/m²; nRMSE =29.14%), whereas Enhanced Normalized Difference Vegetation Index (ENDVI) was found as best predictor for Nitrogen (N) level estimation (R² = 0.9; RMSE =1.75 g/m²; nRMSE =14.59%).

摘要

基于无人机 (UAV) 的遥感是作物管理的现代技术之一，已在本研究中用于估计甜叶菊的生物量和氮 (N) 水平，甜叶菊是一种用作糖替代品的药用作物天然甜味剂。对甜叶菊进行不同水平的氮处理，收获作物用于生物量估算。机载云母感Altum多光谱传感器用于获取作物的图像数据。线性回归模型用于使用 K 折交叉验证方法检查最佳植被指数。过量绿色指数 (ExG) 被确定为生物量估算的最佳植被指数（R ² = 0.7；RMSE =23.77 g/m ²; nRMSE =29.14%)，而增强归一化差异植被指数 (ENDVI) 被认为是氮 (N) 水平估计的最佳预测指标（R ² = 0.9；RMSE =1.75 g/m ²；nRMSE =14.59%）。