Scientia Silvae Sinicae ›› 2024, Vol. 60 ›› Issue (5): 127-138.doi: 10.11707/j.1001-7488.LYKX20220545
• Research papers • Previous Articles Next Articles
Guangdao Bao1,Ting Liu1,Zhonghui Zhang1,*,Zhibin Ren2,Chang Zhai3,Mingming Ding1,Xuefei Jiang4
Received:
2022-08-07
Online:
2024-05-25
Published:
2024-06-14
Contact:
Zhonghui Zhang
CLC Number:
Guangdao Bao,Ting Liu,Zhonghui Zhang,Zhibin Ren,Chang Zhai,Mingming Ding,Xuefei Jiang. Remote Sensing Inversion of Effective Leaf Area Index of Four Coniferous Forest Types and Their Spatial Distribution Rule in Changbai Mountain[J]. Scientia Silvae Sinicae, 2024, 60(5): 127-138.
Table 1
Descriptive statistics of LAIe at sampling points"
类型 Type | 样地数量 Plot number | 最小值 Minimum | 最大值 Maximum | 平均值 Mean | 标准差 Standard deviation | 偏度 Skewness | 峰度 Peakness |
长白落叶松Larix olgensis forest | 14 | 1.65 | 3.45 | 2.51 | 0.27 | 1.27 | 2.24 |
樟子松Pinus sylvestris var. mongolica forest | 15 | 1.86 | 3.79 | 2.72 | 0.23 | 2.32 | 7.79 |
红松Pinus koraiensis forest | 15 | 1.06 | 3.24 | 1.95 | 0.24 | 1.32 | 3.19 |
红皮云杉Picea koraiensis forest | 14 | 1.72 | 4.37 | 2.87 | 0.31 | 0.26 | ?0.05 |
全样本Full samples | 58 | 1.06 | 4.37 | 2.43 | 0.38 | 1.62 | 4.75 |
Table 2
Definition and sources of vegetation index based on Sentinel-2A data"
名称及来源 Name and source | 公式 Formula |
增强植被指数Enhanced vegetation index (EVI) | 2.5× (b8?b4) / (1+ b8 + 6×b4?7.5× b2+1) |
反红边叶绿素指数Inverted red-edge chlorophyll index (IRECI) | (b7 ? b4) × (b6/b5) |
改进简单植被指数Modified simple ratio (MSR) | [(b7/b4) – 1]/[(b7/b4) +1] |
归一化水体指数Normalized difference water index (NDWI) | (b2 - b4) / (b2 + b4) |
归一化植被指数Normalized difference vegetation index(NDVI) | (b8a ? b4) / (b8a + b4) |
土壤调节植被指数Soil adjusted vegetation index (SAVI) | 1.5× (b8a? b4) / (b8a+ b4+0.5) |
简单植被指数Simple ratio (SR) | b8a / b4 |
Table 3
Statistics of classification results of different coniferous forest types"
类型 Type | 斑块数 Patches number | 面积 Area/hm2 | 平均斑块面积 Average area of patches/hm2 | 制图精度 Mapping accuracy(%) | 用户精度 User accuracy(%) |
长白落叶松Larix olgensis forest | 2 552 | 5 344.85 | 2.09 | 89.5 | 90.2 |
樟子松Pinus sylvestris var. mongolica forest | 148 | 245.58 | 1.66 | 87.6 | 89.4 |
红松Pinus koraiensis forest | 780 | 1 319.52 | 1.69 | 91.2 | 92.7 |
红皮云杉Picea koraiensis forest | 763 | 1 085.61 | 1.42 | 90.4 | 92.3 |
Table 4
Correlation coefficients between vegetation index and LAIe of different forest types"
植被指数 Vegetation index | 长白落叶松 Larix olgensis forest | 樟子松 Pinus sylvestris var. mongolica forest | 红松 Pinus koraiensis forest | 红皮云杉 Picea koraiensis forest | 全样本 Full sample |
EVI | 0.629** | 0.682** | 0.367* | 0.782** | 0.602** |
IRECI | 0.891** | 0.859** | 0.905** | 0.602** | 0.714** |
MSR | 0.868** | 0.805** | 0.891** | 0.685** | 0.778** |
NDWI | ?0.819** | ?0.763** | ?0.795** | ?0.650** | ?0.685** |
NDVI | 0.844** | 0.805** | 0.816** | 0.708** | 0.723** |
SAVI | 0.767** | 0.784** | 0.641** | 0.628** | 0.631** |
SR | 0.710** | 0.621** | 0.776** | 0.396* | 0.620** |
Table 5
Regression parameters of leaf area index of different forest types"
类型 Type | 变量 Variable | 斜率 Slope | 截距 Incept | P | R2 | RMSE | MAE | RPD |
长白落叶松Larix olgensis forest | IRECI | 0.691 | 0.006 | 0.000 | 0.813 | 0.435 | 0.427 | 1.657 |
樟子松Pinus sylvestris var. mongolica forest | IRECI | 0.513 | 0.558 | 0.000 | 0.771 | 0.619 | 0.434 | 1.982 |
红松Pinus koraiensis forest | IRECI | 0.667 | 0.203 | 0.000 | 0.842 | 0.374 | 0.446 | 1.736 |
红皮云杉Picea koraiensis forest | EVI | 1.132 | ?0.439 | 0.000 | 0.693 | 0.891 | 0.605 | 1.608 |
全样本Full samples | MSR | 0.551 | 0.479 | 0.000 | 0.615 | 1.364 | 0.911 | 1.015 |
Fig.3
Regression analysis of measured and predicted LAIe for different models The solid red line represents the single tree species model, the solid black line represents the full sample model, the solid blue line represents the PROSAIL model, and the dashed line represents the 1∶1 relationship line."
Table 6
Statistical results of trends between different forest types LAIe and geographical factors"
类型 Type | 地理因子 Geographical factors | 斜率 Slope | 截距 Incept | P | R2 |
长白落叶松Larix olgensis forest | 海拔 Altitude | ?0.000 4 | 2.191 | 0.019* | 0.001 |
坡度 Slope | 0.010 5 | 1.910 | 0.000** | 0.028 | |
坡向 Aspect | 0.000 1 | 2.030 | 0.302 | 0.001 | |
樟子松Pinus sylvestris var. mongolica forest | 海拔 Altitude | ?0.000 3 | 2.246 | 0.052 | 0.017 |
坡度 Slope | 0.009 1 | 1.745 | 0.004** | 0.036 | |
坡向 Aspect | 0.000 4 | 1.765 | 0.071 | 0.015 | |
红松Pinus koraiensis forest | 海拔 Altitude | ?0.003 5 | 5.845 | 0.000** | 0.241 |
坡度 Slope | 0.042 9 | 1.701 | 0.000** | 0.218 | |
坡向 Aspect | ?0.000 7 | 2.401 | 0.083 | 0.007 | |
红皮云杉Picea koraiensis forest | 海拔 Altitude | ?0.002 2 | 4.306 | 0.000** | 0.043 |
坡度 Slope | ?0.006 4 | 1.816 | 0.354 | 0.003 | |
坡向 Aspect | 0.000 3 | 1.731 | 0.233 | 0.004 |
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