植被物候提取方法及物候趋势监测是准确反映植被生长状态的关键环节.基于中等空间分辨率成像光谱仪(MODIS)的归一化植被指数(Normalized Difference Vegetation Index,NDVI)、增强型植被指数(Enhanced Vegetation Index,EVI)产品,提取了三江平原典型沼泽湿地草本植物的12个物候参数,通过Pearson相关性分析、Mann-Kendall突变检验、Mann-Kendall趋势检验、方差分析等方法,探究不同属沼泽植物的物候提取值差异及其变化特征与趋势,揭示了陆地表面物候与物候观测值的差异.结果表明:①Gu方法是三江沼泽湿地植物物候曲线拟合方法中最合适的,EVI数据提取的地面物候参数优于NDVI数据.②TRS1方法在提取春季物候参数(Start Of Season,SOS)上更为准确,Klosterman方法在提取秋季物候参数(End of Season,EOS)上更为准确.③最佳方法下薹草属SOS提前趋势为0.63 d/a,甜茅属EOS提前趋势为0.49 d/a.研究结果可为三江平原湿地植被保护性研究以及适应未来气候变化等方面提供借鉴.
Phenological Changes of Herbaceous Vegetation in Marsh Wetland based on Multiple Methods
Vegetation phenology extraction methods and phenological trend monitoring are the key links to accu-rately reflect the growth status of vegetation.Based on the Normalized Difference Vegetation Index(NDVI)and Enhanced Vegetation Index(EVI)products of Medium Spatial Resolution Imaging Spectroscopy(MO-DIS),12 phenological parameters of herbaceous plants in typical swamp wetlands in the Sanjiang Plain were ex-tracted.Mann-Kendall mutation test,Mann-Kendall trend test,analysis of variance and other methods were used to explore the differences in phenological extraction values and their change characteristics and trends of dif-ferent genera of swamp plants,and revealed the differences between land surface phenology and phenological observations.The results showed that:(1)The Gu method was the most suitable method for fitting plant phe-nological curves in Sanjiang swamp wetland,and the ground phenological parameters extracted from EVI data were better than those of NDVI data.(2)The TRS1 method was more accurate in extracting the spring pheno-logical parameters(Start Of Season)(SOS),and the Klosterman method was more accurate in extracting the autumn phenological parameters(End of Season)(EOS).(3)Under the optimal method,the advance trend of SOS was 0.63 Day/Year,and the advance trend of EOS was 0.49 Day/Year.The results of this study can pro-vide reference for the conservation of wetland vegetation in the Sanjiang Plain and the adaptation to future cli-mate change.
Phenofit packageSanjiang PlainGrowth curve fittingPhenological extraction methodTrend of phenology
万方数据
维普
