CNLTSI: A Dataset of Trophic State Index for Nationwide Lakes in China

Trophic state index (TSI) serves as a key indicator for understanding the spatial pattern and temporal variation in the lake eutrophication, which has not been fully explored for long-term environmental monitoring, especially for small and medium lakes. Landsat satellites provide the capability of monitoring the temporal and spatial distribution of small lakes with 30 m spatial resolution, which offers an effective complement. Here we generated a dataset of TSI for lakes in China (CNLTSI) using Landsat archives (Landsat-5 TM, Landsat-7 ETM+, and Landsat-8 OLI), which contains over 2693 predominantly small to medium nationwide lakes in China. The dataset produced has a spatial resolution of 30 m and varying temporal resolution due to differences in satellite overpass and cloud interference.营养状态指数（Trophic state index，TSI）是解析湖泊富营养化空间格局与时间演变的核心指标，但其在长期环境监测中的应用尚未得到充分探索，针对中小型湖泊的相关研究尤为不足。陆地卫星（Landsat）系列凭借30米的空间分辨率，具备监测小型湖泊时空分布的能力，可为相关监测提供有效补充。本研究基于Landsat存档数据（包含Landsat-5 TM、Landsat-7 ETM+及Landsat-8 OLI），构建了中国湖泊营养状态指数数据集（CNLTSI），涵盖全国范围内2693余个以中小型湖泊为主的水体。该数据集空间分辨率为30米，受卫星过境频次与云量干扰的差异影响，其时间分辨率存在一定波动。