Delta size and plant density experiments

Experiments were conducted to examine the effects of delta size and plant patchiness on channel network organization in river deltas. This dataset contains five experiments that were described in detail in Piliouras & Kim (2019) doi: 10.1002/esp.4492. The experiments in this dataset correlate to those in the paper labeled Runs 1-5 as follows, Run 1 = Run1_noAlfalfa; Run 2 = Run2_Alfalfa; Run3 = Run3_Alfalfa; Run 4 = Run3b_noAlfalfa; Run 5 = Run3b_Alfalfa. There are two unvegetated experiments: Run1_noAlfalfa and Run3b_noAlfalfa. The three vegetated experiments are Run2_Alfalfa, Run3_Alfalfa, and Run3b_Alfalfa. Runs 1, 2, and 3 all started with smaller deltas that were approximately 0.5 m in length, while the two Runs labeled 3b started with larger deltas that were approximately 1 m in length. Run 2 had dense uniform seeding of 1-2 seeds per square cm, while Runs 3 and 3b had sparse uniform seeding of ~0.5 seeds per square cm. Alfalfa was used for vegetation, and seeds were dispersed manually to cover the delta surface. All experiments were initially run at a 'flood' discharge to grow the delta to either 0.5 m in length (Runs 1-3) or 1 m in length (Runs 3b Alfalfa and noAlfalfa). After this initial delta growth stage, discharge cycled between floods and interfloods, where interfloods had half of the flood water discharge and no sediment input. Vegetated experiments were seeded in between the flood and interflood, such that interfloods could remove some seeds from the delta topset. After a cycle of flood-seeding-interflood, plants were allowed to grow for three days before beginning another flood cycle. Full details of the experimental parameters and methods can be found in Table 1 and the methods section in the paper referenced above. This dataset includes several image types for each experiment: (1) raw unprocessed time lapse photos for all floods and interfloods; (2) binary masks of delta topsets; (3) binary masks of wetted area; and (4) binary masks of vegetation cover, only for experiments that had vegetation. The time lapse images are the original photos taken during the experiments (every 15 seconds) and have not been resized, scaled, or corrected for lens distortion. Time lapse photos were rescaled to 1 mm per pixel, corrected for lens distortion, and cropped to make the various binary masks. All binary images are therefore at a resolution of 1 mm per pixel. Time lapse images were then manually masked to the shoreline and thresholded to make the topset binary images. Other binary images were made in photoshop by thresholding the color intensities for the red (wetted area) or green (vegetation) channel.本研究开展系列实验，以探究三角洲规模与植物斑块分布格局对河流三角洲河道网络格局的影响。本数据集包含5组实验，相关细节已在Piliouras与Kim（2019）发表的论文（DOI: 10.1002/esp.4492）中详细阐述。本数据集内的5组实验与该论文中标注为Run 1至Run 5的实验对应关系如下：Run 1 = Run1_noAlfalfa；Run 2 = Run2_Alfalfa；Run3 = Run3_Alfalfa；Run 4 = Run3b_noAlfalfa；Run 5 = Run3b_Alfalfa。其中2组为无植被实验：Run1_noAlfalfa与Run3b_noAlfalfa；剩余3组为有植被实验：Run2_Alfalfa、Run3_Alfalfa及Run3b_Alfalfa。 Run 1、2、3的初始三角洲规模均约为0.5米，而标注为3b的2组实验初始三角洲规模约为1米。Run 2采用每平方厘米1~2粒种子的高密度均匀播种，Run 3与3b则采用每平方厘米约0.5粒种子的低密度均匀播种。实验选用紫花苜蓿（Alfalfa）作为植被，种子通过人工播撒覆盖三角洲表面。 所有实验初始均以“洪水”流量运行，将三角洲培育至0.5米长（Run 1~3）或1米长（Run 3b的有植被与无植被组）。初始三角洲培育阶段结束后，流量切换为洪水期与间歇期交替模式：间歇期的流量为洪水期的一半，且无泥沙输入。有植被实验在洪水期与间歇期之间完成播种，以便间歇期可移除部分三角洲顶面（delta topset）的种子。每一轮洪水-播种-间歇期循环结束后，需等待3天待植物生长完成，再开启下一轮洪水周期。实验参数与方法的完整细节可参见上述参考文献中的表1与方法章节。 本数据集为每组实验提供四类数据：(1) 所有洪水期与间歇期的原始未处理延时摄影照片；(2) 三角洲顶面的二值掩膜（binary masks）；(3) 湿润区域的二值掩膜；(4) 植被覆盖区域的二值掩膜，仅适用于有植被的实验。延时摄影照片为实验过程中每15秒拍摄的原始照片，未经过尺寸调整、缩放或镜头畸变校正。后续通过将延时摄影照片缩放至1毫米每像素、校正镜头畸变并裁剪，生成各类二值掩膜，因此所有二值图像的分辨率均为1毫米每像素。延时摄影照片需手动沿海岸线进行掩膜处理并阈值化，以生成顶面二值掩膜。其余二值掩膜则通过在Photoshop中对红色通道（对应湿润区域）或绿色通道（对应植被覆盖）的颜色强度进行阈值化处理生成。