Understanding the spatial expansion process of salt marshes and quantifying the factors driving this expansion are crucial for the management and restoration of coastal wetlands. In this study, we aimed to illustrate the expansion process of Scirpus mariqueter using drone remote sensing and quantify its relationship with habitat quality. Our hypothesis was that landscape metrics could serve as valuable indicators for prioritizing habitat restoration efforts along the coast. We utilized drone remote sensing and adopted the simple Greenness Index to reflect the growth status of S. mariqueter. Using this index, we computed the standard deviation ellipse and growth center. To evaluate habitat quality, we developed a method based on our previous research and other relevant reports. We then conducted a quantitative analysis of the expansion process of S. mariqueter in areas with varying habitat quality. We found that S. mariqueter’s optimal elevation was 3.7 m, with a range of 2.5 to 4.3 m. The threshold value for soil total nitrogen was 0.3 g/kg, and the tolerance threshold for soil salinity was 2500 ppm. These three factors, elevation, soil total nitrogen, and soil salinity, collectively influenced habitat quality, with weights of 0.68, 0.23, and 0.09, respectively, as determined through geodetector analysis. During the summer, we observed a dominance of dispersal in S. mariqueter, with the species primarily spreading to areas with increased habitat quality. Patch shapes tended to be compact and regular in this season. In contrast, during the autumn, a dominance of decline was observed, with S. mariqueter mainly distributing to areas exhibiting decreased habitat quality. Patch shapes tended to be complex and irregular in the autumn season. Eventually micro-geomorphic modification and patch shape filling methods based on UAV observations are proposed to aid wetland restoration. These findings are of utmost importance for the restoration of coastal wetlands and the enhancement of ecosystem resilience.

了解盐沼的空间扩张过程并量化驱动这种扩张的因素对于沿海湿地的管理和恢复至关重要。在这项研究中，我们的目的是利用无人机遥感来说明海三棱草的扩张过程，并量化其与栖息地质量的关系。我们的假设是，景观指标可以作为优先考虑沿海栖息地恢复工作的有价值的指标。我们利用无人机遥感，采用简单的绿度指数来反映S. mariqueter的生长状况。使用该指数，我们计算了标准差椭圆和增长中心。为了评估栖息地质量，我们根据之前的研究和其他相关报告开发了一种方法。然后，我们对S. mariqueter在不同栖息地质量的地区的扩张过程进行了定量分析。我们发现S. mariqueter的最佳海拔为3.7 m，范围为2.5至4.3 m。土壤全氮阈值为0.3 g/kg，土壤盐分耐受阈值为2500 ppm。通过地理探测器分析确定，海拔、土壤全氮和土壤盐度这三个因素共同影响生境质量，权重分别为0.68、0.23和0.09。在夏季，我们观察到S. mariqueter的扩散占主导地位，该物种主要扩散到栖息地质量提高的地区。本季贴片形状趋于紧凑、规则。相反，在秋季，观察到下降的趋势， S. mariqueter主要分布在栖息地质量下降的地区。 秋季斑块形状往往复杂且不规则。最终提出了基于无人机观测的微地貌改造和斑块形状填充方法来帮助湿地恢复。这些发现对于恢复沿海湿地和增强生态系统的恢复力至关重要。