LBA-ECO LC-07 Amazon Floodplain Lake Chlorophyll from MODIS, Para, Brazil: 2002-2003

This data set contains chlorophyll concentration maps of the Amazon River floodplain region from Parintins (Amazonas) to Almeirim (Para). These chlorophyll fraction maps were derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) surface reflectance product (MOD09) for 19 months from April 2002 to December 2003.

The study was conducted in a floodplain reach upstream from Santarem, Para, in order to assess seasonal changes in phytoplanktonic chlorophyll-a distributions in the floodplain Lake Curuai. MODIS reflectance data were acquired at four river stages: rising (April), high (June), decreasing (September), and low (November). Chlorophyll maps were derived and used to compute the weighted average of chlorophyll concentration from MODIS images in the region. Field measurements of suspended inorganic matter and chlorophyll-a in Lake Curuai were made almost concurrently with satellite overpasses (Barbosa, 2005). The images and the estimated chlorophyll concentrations were compared to measured chlorophyll concentrations at control points for different hydrological states. This data set may be applied to better understand the seasonal dynamics of primary production of the Amazon floodplains. The maps of chlorophyll-a concentration may be used to model spatial and temporal variations of primary production in this region.

The monthly chlorophyll-a maps are provided as GeoTIFF files. There are two formats: (1) color-mapped pixels and (2) pixels as chlorophyll-a concentrations. These latter images are not intended for browsing. These images have pixel values that are the chlorophyll-a concentration in mg/m3 and need to be download and opened in GIS software.

本数据集收录了亚马逊河流域平原地区，自帕林廷斯（亚马孙州）至阿尔梅里姆（帕拉州）的叶绿素浓度地图。这些叶绿素浓度分布图源自中等分辨率成像光谱辐射计（MODIS）表面反射率产品（MOD09），时间跨度为2002年4月至2003年12月共19个月。研究在帕拉州的桑塔雷姆上游的河漫滩区域进行，旨在评估河漫滩库拉维湖中浮游植物叶绿素-a的季节性分布变化。MODIS反射率数据在四个河流阶段采集：上升期（4月）、高峰期（6月）、下降期（9月）和低潮期（11月）。通过MODIS图像在该区域的叶绿素浓度计算得出叶绿素地图，并用于计算叶绿素浓度的加权平均值。与卫星过境几乎同时，在库拉维湖进行了悬浮无机物和叶绿素-a的现场测量（Barbosa，2005年）。图像及估算的叶绿素浓度与不同水文状态下的控制点的实测叶绿素浓度进行了比较。本数据集可用于更深入理解亚马逊河漫滩初级生产的季节动态。叶绿素-a浓度图可用于模拟该区域初级生产在空间和时间上的变化。月度叶绿素-a地图以GeoTIFF格式提供，包括两种格式：（1）彩色映射像素和（2）叶绿素-a浓度像素。后一种图像不适用于浏览。这些图像的像素值代表叶绿素-a浓度，单位为mg/m3，需下载并在GIS软件中打开。