The availability of high spatial resolution synthetic aperture radar (SAR) sensors with a wide range of acquisition modes has increased greatly over the past decade and contributed significantly to the study of wetland ecosystems. However, the relative influence of acquisition configurations (i.e. band frequency, polarization mode, number of acquisition dates) in wetland analysis remains poorly explored. This article investigated the relative influence of X-/C-band frequency, dual-/quad-polarization and single-/multi-acquisition features on discrimination of vegetation types in 632 ha Ramsar-protected temperate riverine marshes (Mont-Saint-Michel Bay, France). Three SAR datasets (i.e. quad-pol/C-band, dual-pol/C-band and dual-pol/X-band) were generated from five pairs of TerraSAR-X and RADARSAT-2 images. First, a set of 25 SAR features, including backscattering coefficients and polarimetric parameters, was extracted from the SAR datasets. Second, correlation between each pair of images was calculated using the polarimetric parameter Shannon entropy to select the most similar pairs in the time series. Third, the importance of each SAR feature and modeling accuracy were calculated using a conditional random forest model for each of the three datasets. Finally, analysis of variance was performed to assess the impact of band frequency, polarization mode and number of acquisition dates on the classification of vegetation types. The results highlighted that although the time-shift of each pair of TerraSAR-X and RADARSAT-2 images was short (3–11 days), only three pairs were sufficiently similar, highlighting the high variability in wetland ecosystems. The polarimetric parameter Shannon entropy was the most discriminating feature, regardless of the frequency or polarization. Most variance in the model accuracy was explained by the number of acquisition dates (68%), followed by the frequency (23%), while polarization explained little. This article will help select the most suitable SAR sensor acquisition modes for wetland conservation.

在过去的十年中，具有多种采集模式的高空间分辨率合成孔径雷达（SAR）传感器的可用性大大提高，并为湿地生态系统的研究做出了重要贡献。但是，在湿地分析中采集配置（即频带频率，极化模式，采集日期数）的相对影响仍未得到很好的探讨。本文研究了X- / C波段频率，双/四极化和单/多采集特征对632公顷受拉姆萨尔保护的温带河流沼泽地（圣米歇尔湾）植被类型的相对影响，法国）。从五对TerraSAR-X和RADARSAT-2图像中生成了三个SAR数据集（即，四极/ C波段，双极/ C波段和双极/ X波段）。首先，一组25种SAR功能 从SAR数据集中提取了包括反向散射系数和极化参数的数据。其次，使用极化参数Shannon熵计算每对图像之间的相关性，以选择时间序列中最相似的图像对。第三，使用条件随机森林模型针对三个数据集的每一个计算每个SAR特征的重要性和建模精度。最后，进行方差分析以评估频带频率，极化模式和采集日期数对植被类型分类的影响。结果突出表明，尽管每对TerraSAR-X和RADARSAT-2图像的时移都很短（3-11天），但只有三对足够相似，这突出表明了湿地生态系统的高度可变性。极化参数Shannon熵是最明显的特征，与频率或极化无关。模型准确性的最大差异是由采集日期的数量（68％），随后的频率（23％）解释的，而极化解释得很少。本文将帮助选择最适合湿地保护的SAR传感器采集模式。