文献类型： 外文期刊

作者： Sawut, Mamat ¹ ; Hu, Xin ¹ ; Manlike, Asiya ⁴ ; Aimaier, Ainiwan ⁴ ; Cui, Jintao ¹ ; Liang, Jiaxi ¹ ;

作者机构： 1.Xinjiang Univ, Coll Geog & Remote Sensing Sci, Urumqi 830017, Peoples R China

2.Xinjiang Univ, Xinjiang Key Lab Oasis Ecol, Urumqi 830017, Peoples R China

3.Xinjiang Univ, Key Lab Smart City & Environm Modelling Higher Edu, Urumqi 830017, Peoples R China

4.Xinjiang Acad Anim Sci, Grassland Res Inst, Urumqi 830057, Peoples R China

5.Xinjiang Acad Anim Sci, Field Orientat Observat & Res Stn Grassland Ecol E, Urumqi 830057, Peoples R China

关键词： LAI; fractional-order differentiation; feature band selection; three-band indices; hyperspectral estimation

期刊名称：FORESTS （ 影响因子：2.5； 五年影响因子：2.7 ）

ISSN：

年卷期： 2024 年 15 卷 12 期

页码：

收录情况： SCI

摘要： The Leaf Area Index (LAI) is a key indicator for assessing fruit tree growth and productivity, and accurate estimation using hyperspectral technology is essential for monitoring plant health. This study aimed to improve LAI estimation accuracy in apricot, jujube, and walnut trees in Xinjiang, China. Canopy hyperspectral data were processed using fractional-order differentiation (FOD) from 0 to 2.0 orders to extract spectral features. Three feature selection methods-Competitive Adaptive Reweighted Sampling (CARS), Successive Projections Algorithm (SPA), and their combination (CARS-SPA)-were applied to identify sensitive spectral bands. Various band combinations were used to construct three-band indices (TBIs) for optimal LAI estimation. Random forest (RF) models were developed and validated for LAI prediction. The results showed that (1) the reflectance spectra of jujube and walnut trees were similar, while apricot spectra differed. (2) The correlation between fractional-order differential spectra and LAI was highest at orders 1.4 and 1.7, outperforming integer-order spectra. (3) The CARS-SPA selected a smaller set of feature bands in the 1100 similar to 2500 nm, reducing collinearity and improving spectral index construction. (4) The RF model using TBI4 demonstrated high R-2, low RMSE, and an RPD value > 2, indicating optimal prediction accuracy. This approach holds promise for hyperspectral LAI monitoring in fruit trees.