Remote Sensing Phenology of Antarctic Green and Red Snow Algae Using WorldView Satellites.
Remote Sensing Phenology of Antarctic Green and Red Snow Algae Using WorldView Satellites.
复制标题
DOI：
10.3389/fpls.2021.671981
复制
发表时间：
2021
影响因子：
5.6
通讯作者：
Davey MP
中科院分区：
文献类型：
--
作者：
Gray A;Krolikowski M;Fretwell P;Convey P;Peck LS;Mendelova M;Smith AG;Davey MP
雪藻是南极洲重要的陆地光合生物类群，大多生长在低洼的沿海雪原中。由于南极雪藻繁殖的短暂性以及前往那里旅行和工作所需的后勤保障，对南极雪藻进行可靠的观测非常困难。此前的研究曾使用Sentinel 2卫星图像远程探测和监测雪藻华，但受到粗空间分辨率和检测红藻华的困难的限制。在这里，我们首次使用高分辨率 WorldView 多光谱卫星图像来详细研究南极雪藻水华，跟踪整个夏季红色和绿色水华的生长情况。我们的遥感方法是在两个南极野外季节期间开发的，其中使用野外光谱学来构建能够估计细胞密度的检测模型。使用全球定位系统（GPS）标记花朵和原位生命周期分析来验证和验证我们的模型输出。随后，WorldView 图像成功识别了安克雷奇岛（莱德湾，南纬 67°）上的红色和绿色雪藻，估计峰值覆盖范围分别为 9.48 × 104 和 6.26 × 104 平方米。总而言之，这大于使用归一化差异植被指数测量的岛屿陆地植被面积覆盖率。绿雪藻比红藻具有更大的细胞密度和平均层厚度（6.0 × 104 与 4.3 × 104 细胞 ml−1），因此对于安克雷奇岛，我们估计绿藻干生物量是红藻的三倍以上（分别为 567 公斤和 180 公斤）。由于 WorldView 图像的高空间分辨率及其检测红色水华的能力，计算出的雪藻面积比 Sentinel 2 图像估计的面积大 17.5 倍。这凸显了使用粗分辨率图像的缩放问题，并表明雪藻对南极洲净初级生产力的贡献可能远远大于之前认识的。
Snow algae are an important group of terrestrial photosynthetic organisms in Antarctica, where they mostly grow in low lying coastal snow fields. Reliable observations of Antarctic snow algae are difficult owing to the transient nature of their blooms and the logistics involved to travel and work there. Previous studies have used Sentinel 2 satellite imagery to detect and monitor snow algal blooms remotely, but were limited by the coarse spatial resolution and difficulties detecting red blooms. Here, for the first time, we use high-resolution WorldView multispectral satellite imagery to study Antarctic snow algal blooms in detail, tracking the growth of red and green blooms throughout the summer. Our remote sensing approach was developed alongside two Antarctic field seasons, where field spectroscopy was used to build a detection model capable of estimating cell density. Global Positioning System (GPS) tagging of blooms and in situ life cycle analysis was used to validate and verify our model output. WorldView imagery was then used successfully to identify red and green snow algae on Anchorage Island (Ryder Bay, 67°S), estimating peak coverage to be 9.48 × 104 and 6.26 × 104 m2, respectively. Combined, this was greater than terrestrial vegetation area coverage for the island, measured using a normalized difference vegetation index. Green snow algae had greater cell density and average layer thickness than red blooms (6.0 × 104 vs. 4.3 × 104 cells ml−1) and so for Anchorage Island we estimated that green algae dry biomass was over three times that of red algae (567 vs. 180 kg, respectively). Because the high spatial resolution of the WorldView imagery and its ability to detect red blooms, calculated snow algal area was 17.5 times greater than estimated with Sentinel 2 imagery. This highlights a scaling problem of using coarse resolution imagery and suggests snow algal contribution to net primary productivity on Antarctica may be far greater than previously recognized.
登录
查看更多内容
影响因子：
3.6
作者：
Fujii, Masanori;Takano, Yoshinori;Kojima, Hisaya;Hoshino, Tamotsu;Tanaka, Ryouichi;Fukui, Manabu
通讯作者：
Fukui, Manabu
DOI：
10.1073/pnas.032206999
发表时间：
2002-02-19
影响因子：
11.1
作者：
Dierssen, HM;Smith, RC;Vernet, M
通讯作者：
Vernet, M
影响因子：
13.5
作者：
Dozier, Jeff;Green, Robert O.;Painter, Thomas H.
通讯作者：
Painter, Thomas H.
影响因子：
4.2
作者：
Dial, Roman J.;Ganey, Gerard Q.;Skiles, S. McKenzie
通讯作者：
Skiles, S. McKenzie
影响因子：
4.6
作者：
Di Mauro, B.;Garzonio, R.;Rossini, M.
通讯作者：
Rossini, M.