Google Earth Engine (GEE) is an ideal platform for large-scale geospatial agricultural and environmental modeling based on its diverse geospatial datasets, easy-to-use APIs, rich reusable library, and high-performance computational capacity. However, using GEE to prepare agricultural land use data for geospatial agricultural and environment modeling requires not only the programming skills of GEE APIs but also the knowledge of the data. This paper presents a toolkit AgKit4EE to facilitate the use of the Cropland Data Layer (CDL) products over GEE platform. The toolkit contains a variety of frequently used functions for use of CDL products including crop sequence modeling, crop frequency modeling, confidence layer modeling, and land use change analysis. The experimental results suggest that the toolkit can significantly reduce the workload for modelers who perform geospatial agricultural and environmental modeling with CDL data as well as developers who build the GEE-enabled cyberinfrastructure for agricultural land use modeling of the conterminous United States.

Google Earth Engine（GEE）基于其多样化的地理空间数据集，易于使用的API，丰富的可重用库以及高性能的计算能力，是进行大规模地理空间农业和环境建模的理想平台。但是，使用GEE为地理空间农业和环境建模准备农业土地利用数据不仅需要GEE API的编程技能，还需要数据知识。本文介绍了一个工具包AgKit4EE，以促进在GEE平台上使用Cropland数据层（CDL）产品。该工具包包含使用CDL产品的各种常用功能，包括作物序列建模，作物频率建模，置信层建模和土地利用变化分析。